CORD-1071 Refactor VTN node service

Done
- Separated interface, implementation and store for node management
- Added unit tests for node manager and handler
- Offloaded more of the event handling off of the Atomix event thread

Todo
- Add REST interface for the node service

Change-Id: Ibf90d3a621013497cc891ca3086db6648f5d49df
diff --git a/src/main/java/org/opencord/cordvtn/api/CordVtnConfig.java b/src/main/java/org/opencord/cordvtn/api/CordVtnConfig.java
index bb4ce5e..69ecbe6 100644
--- a/src/main/java/org/opencord/cordvtn/api/CordVtnConfig.java
+++ b/src/main/java/org/opencord/cordvtn/api/CordVtnConfig.java
@@ -28,12 +28,14 @@
 import org.onlab.packet.TpPort;
 import org.onosproject.cluster.ClusterService;
 import org.onosproject.core.ApplicationId;
+import org.onosproject.net.DeviceId;
 import org.onosproject.net.behaviour.ControllerInfo;
 import org.onosproject.net.config.Config;
 import org.onosproject.net.config.InvalidFieldException;
 import org.opencord.cordvtn.api.net.CidrAddr;
 import org.opencord.cordvtn.api.node.CordVtnNode;
 import org.opencord.cordvtn.api.node.SshAccessInfo;
+import org.opencord.cordvtn.impl.DefaultCordVtnNode;
 import org.slf4j.Logger;
 
 import java.util.List;
@@ -196,31 +198,31 @@
         String ovsdbPort = getConfig(object, OVSDB_PORT);
 
         object.get(CORDVTN_NODES).forEach(vtnNode -> {
-            CidrAddr localMgmt = CidrAddr.valueOf(get(LOCAL_MANAGEMENT_IP, ""));
-            CidrAddr hostsMgmt = CidrAddr.valueOf(getConfig(vtnNode, HOST_MANAGEMENT_IP));
+            CidrAddr localMgmtIp = CidrAddr.valueOf(get(LOCAL_MANAGEMENT_IP, ""));
+            CidrAddr hostsMgmtIp = CidrAddr.valueOf(getConfig(vtnNode, HOST_MANAGEMENT_IP));
 
             SshAccessInfo sshInfo = new SshAccessInfo(
-                    hostsMgmt.ip().getIp4Address(),
+                    hostsMgmtIp.ip().getIp4Address(),
                     TpPort.tpPort(Integer.parseInt(getConfig(sshNode, SSH_PORT))),
                     getConfig(sshNode, SSH_USER),
                     getConfig(sshNode, SSH_KEY_FILE));
 
-            CordVtnNode.Builder nodeBuilder = CordVtnNode.builder()
+            CordVtnNode.Builder nodeBuilder = DefaultCordVtnNode.builder()
                     .hostname(getConfig(vtnNode, HOSTNAME))
-                    .hostMgmtIp(hostsMgmt)
-                    .localMgmtIp(localMgmt)
-                    .dataIp(getConfig(vtnNode, DATA_IP))
+                    .hostManagementIp(hostsMgmtIp)
+                    .localManagementIp(localMgmtIp)
+                    .dataIp(CidrAddr.valueOf(getConfig(vtnNode, DATA_IP)))
                     .sshInfo(sshInfo)
-                    .integrationBridgeId(getConfig(vtnNode, INTEGRATION_BRIDGE_ID))
-                    .dataIface(getConfig(vtnNode, DATA_IFACE));
+                    .integrationBridgeId(DeviceId.deviceId(getConfig(vtnNode, INTEGRATION_BRIDGE_ID)))
+                    .dataInterface(getConfig(vtnNode, DATA_IFACE));
 
             if (!Strings.isNullOrEmpty(ovsdbPort)) {
-                nodeBuilder.ovsdbPort(Integer.parseInt(ovsdbPort));
+                nodeBuilder.ovsdbPort(TpPort.tpPort(Integer.parseInt(ovsdbPort)));
             }
 
             String hostMgmtIface = getConfig(vtnNode, HOST_MANAGEMENT_IFACE);
             if (!Strings.isNullOrEmpty(hostMgmtIface)) {
-                nodeBuilder.hostMgmtIface(hostMgmtIface);
+                nodeBuilder.hostManagementInterface(hostMgmtIface);
             }
 
             nodes.add(nodeBuilder.build());
diff --git a/src/main/java/org/opencord/cordvtn/api/core/CordVtnPipeline.java b/src/main/java/org/opencord/cordvtn/api/core/CordVtnPipeline.java
new file mode 100644
index 0000000..278492a
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/core/CordVtnPipeline.java
@@ -0,0 +1,64 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.core;
+
+import org.onlab.packet.VlanId;
+import org.onosproject.net.flow.FlowRule;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+
+/**
+ * Service providing cordvtn pipeline.
+ */
+public interface CordVtnPipeline {
+
+    // tables
+    int TABLE_ZERO = 0;
+    int TABLE_IN_PORT = 1;
+    int TABLE_ACCESS = 2;
+    int TABLE_IN_SERVICE = 3;
+    int TABLE_DST = 4;
+    int TABLE_TUNNEL_IN = 5;
+    int TABLE_VLAN = 6;
+
+    // priorities
+    int PRIORITY_MANAGEMENT = 55000;
+    int PRIORITY_HIGH = 50000;
+    int PRIORITY_DEFAULT = 5000;
+    int PRIORITY_LOW = 4000;
+    int PRIORITY_ZERO = 0;
+
+    VlanId VLAN_WAN = VlanId.vlanId((short) 500);
+
+    /**
+     * Initializes the pipeline for the supplied node.
+     *
+     * @param node cordvtn node
+     */
+    void initPipeline(CordVtnNode node);
+
+    /**
+     * Clean up the pipeline for all nodes.
+     */
+    void cleanupPipeline();
+
+    /**
+     * Processes the given flow rule.
+     *
+     * @param install install or remove
+     * @param rule    flow rule to process
+     */
+    void processFlowRule(boolean install, FlowRule rule);
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/ConnectionHandler.java b/src/main/java/org/opencord/cordvtn/api/node/ConnectionHandler.java
deleted file mode 100644
index f3e3ad4..0000000
--- a/src/main/java/org/opencord/cordvtn/api/node/ConnectionHandler.java
+++ /dev/null
@@ -1,36 +0,0 @@
-/*
- * Copyright 2015-present Open Networking Laboratory
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-package org.opencord.cordvtn.api.node;
-
-/**
- * Entity capable of handling a subject connected and disconnected situation.
- */
-public interface ConnectionHandler<T> {
-
-    /**
-     * Processes the connected subject.
-     *
-     * @param subject subject
-     */
-    void connected(T subject);
-
-    /**
-     * Processes the disconnected subject.
-     *
-     * @param subject subject.
-     */
-    void disconnected(T subject);
-}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNode.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNode.java
index 153eed3..1e873a4 100644
--- a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNode.java
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNode.java
@@ -15,489 +15,193 @@
  */
 package org.opencord.cordvtn.api.node;
 
-import com.google.common.base.MoreObjects;
-import com.google.common.base.Strings;
-import com.google.common.collect.Sets;
 import org.onlab.packet.TpPort;
 import org.onosproject.net.DeviceId;
 import org.opencord.cordvtn.api.net.CidrAddr;
 
-import java.util.Comparator;
-import java.util.Objects;
-import java.util.Optional;
 import java.util.Set;
 
-import static com.google.common.base.Preconditions.checkArgument;
-import static com.google.common.base.Preconditions.checkNotNull;
-import static org.opencord.cordvtn.api.Constants.DEFAULT_OVSDB_PORT;
-import static org.opencord.cordvtn.api.Constants.DEFAULT_TUNNEL;
-
 /**
- * Representation of a compute infrastructure node for CORD VTN service.
+ * Representation of a compute node for service instance provisioning.
  */
-public final class CordVtnNode {
-
-    private final String hostname;
-    private final CidrAddr hostMgmtIp;
-    private final CidrAddr localMgmtIp;
-    private final CidrAddr dataIp;
-    private final Optional<TpPort> ovsdbPort;
-    private final SshAccessInfo sshInfo;
-    private final DeviceId integrationBridgeId;
-    private final String dataIface;
-    private final Optional<String> hostMgmtIface;
-    private final CordVtnNodeState state;
-
-    public static final Comparator<CordVtnNode> CORDVTN_NODE_COMPARATOR =
-            (node1, node2) -> node1.hostname().compareTo(node2.hostname());
+public interface CordVtnNode {
 
     /**
-     * Creates a new node.
-     *
-     * @param hostname hostname
-     * @param hostMgmtIp host management network address
-     * @param localMgmtIp local management network address
-     * @param dataIp data network address
-     * @param ovsdbPort port number for ovsdb connection
-     * @param sshInfo ssh access information
-     * @param integrationBridgeId integration bridge identifier
-     * @param dataIface data plane interface name
-     * @param hostMgmtIface host management network interface
-     * @param state cordvtn node state
-     */
-    private CordVtnNode(String hostname,
-                        CidrAddr hostMgmtIp,
-                        CidrAddr localMgmtIp,
-                        CidrAddr dataIp,
-                        Optional<TpPort> ovsdbPort,
-                        SshAccessInfo sshInfo,
-                        DeviceId integrationBridgeId,
-                        String dataIface,
-                        Optional<String> hostMgmtIface,
-                        CordVtnNodeState state) {
-        this.hostname = hostname;
-        this.hostMgmtIp = hostMgmtIp;
-        this.localMgmtIp = localMgmtIp;
-        this.dataIp = dataIp;
-        this.ovsdbPort = ovsdbPort;
-        this.sshInfo = sshInfo;
-        this.integrationBridgeId = integrationBridgeId;
-        this.dataIface = dataIface;
-        this.hostMgmtIface = hostMgmtIface;
-        this.state = state;
-    }
-
-    /**
-     * Returns cordvtn node with new state.
-     *
-     * @param node cordvtn node
-     * @param state cordvtn node init state
-     * @return cordvtn node
-     */
-    public static CordVtnNode getUpdatedNode(CordVtnNode node, CordVtnNodeState state) {
-        return new CordVtnNode(node.hostname,
-                               node.hostMgmtIp, node.localMgmtIp, node.dataIp,
-                               node.ovsdbPort,
-                               node.sshInfo,
-                               node.integrationBridgeId,
-                               node.dataIface, node.hostMgmtIface,
-                               state);
-    }
-
-    /**
-     * Returns the hostname.
+     * Returns the hostname of the node.
      *
      * @return hostname
      */
-    public String hostname() {
-        return this.hostname;
-    }
+    String hostname();
 
     /**
-     * Returns the host management network address.
+     * Returns the host management IP address of the node.
      *
-     * @return network address
+     * @return ip address with cidr notation
      */
-    public CidrAddr hostMgmtIp() {
-        return this.hostMgmtIp;
-    }
+    CidrAddr hostManagementIp();
 
     /**
-     * Returns the local management network address.
+     * Returns the local management IP address of the node.
      *
-     * @return network address
+     * @return ip address with the cidr notation
      */
-    public CidrAddr localMgmtIp() {
-        return this.localMgmtIp;
-    }
+    // TODO remove this after dynamic provisioning of local management network
+    CidrAddr localManagementIp();
 
     /**
-     * Returns the data network address.
+     * Returns the data network IP address of the node.
      *
-     * @return network address
+     * @return ip address with the cidr notation
      */
-    public CidrAddr dataIp() {
-        return this.dataIp;
-    }
+    CidrAddr dataIp();
 
     /**
-     * Returns the port number used for OVSDB connection.
-     * It returns default OVSDB port 6640, if it's not specified.
+     * Returns the integration bridge device identifier.
      *
-     * @return port number
+     * @return device id
      */
-    public TpPort ovsdbPort() {
-        if (this.ovsdbPort.isPresent()) {
-            return this.ovsdbPort.get();
-        } else {
-            return TpPort.tpPort(DEFAULT_OVSDB_PORT);
-        }
-    }
+    DeviceId integrationBridgeId();
+
+    /**
+     * Returns the data network interface name.
+     *
+     * @return interface name
+     */
+    String dataInterface();
+
+    /**
+     * Returns host management network interface name.
+     *
+     * @return interface name; null if not set
+     */
+    String hostManagementInterface();
+
+    /**
+     * Returns the port number of the OVSDB server.
+     *
+     * @return port number; 6640 if not set
+     */
+    TpPort ovsdbPort();
 
     /**
      * Returns the SSH access information.
      *
      * @return ssh access information
      */
-    public SshAccessInfo sshInfo() {
-        return this.sshInfo;
-    }
-
-    /**
-     * Returns the identifier of the integration bridge.
-     *
-     * @return device id
-     */
-    public DeviceId integrationBridgeId() {
-        return this.integrationBridgeId;
-    }
-
-    /**
-     * Returns the identifier of the OVSDB device.
-     *
-     * @return device id
-     */
-    public DeviceId ovsdbId() {
-        return DeviceId.deviceId("ovsdb:" + this.hostMgmtIp.ip().toString());
-    }
-
-    /**
-     * Returns data network interface name.
-     *
-     * @return data network interface name
-     */
-    public String dataIface() {
-        return this.dataIface;
-    }
-
-    /**
-     * Returns host management network interface name.
-     *
-     * @return host management network interface name
-     */
-    public Optional<String> hostMgmtIface() {
-        return this.hostMgmtIface;
-    }
-
-    /**
-     * Returns a set of network interfaces for the VTN service to work properly.
-     *
-     * @return set of interface names
-     */
-    public Set<String> systemIfaces() {
-        Set<String> ifaces = Sets.newHashSet(DEFAULT_TUNNEL, dataIface);
-        if (hostMgmtIface.isPresent()) {
-            ifaces.add(hostMgmtIface.get());
-        }
-        return ifaces;
-    }
+    SshAccessInfo sshInfo();
 
     /**
      * Returns the state of the node.
      *
      * @return state
      */
-    public CordVtnNodeState state() {
-        return this.state;
-    }
-
-    @Override
-    public boolean equals(Object obj) {
-        if (this == obj) {
-            return true;
-        }
-
-        if (obj instanceof CordVtnNode) {
-            CordVtnNode that = (CordVtnNode) obj;
-            if (Objects.equals(hostname, that.hostname) &&
-                    Objects.equals(hostMgmtIp, that.hostMgmtIp) &&
-                    Objects.equals(localMgmtIp, that.localMgmtIp) &&
-                    Objects.equals(dataIp, that.dataIp) &&
-                    Objects.equals(ovsdbPort, that.ovsdbPort) &&
-                    Objects.equals(sshInfo, that.sshInfo) &&
-                    Objects.equals(integrationBridgeId, that.integrationBridgeId) &&
-                    Objects.equals(dataIface, that.dataIface) &&
-                    Objects.equals(hostMgmtIface, that.hostMgmtIface)) {
-                return true;
-            }
-        }
-        return false;
-    }
-
-    @Override
-    public int hashCode() {
-        return Objects.hash(hostname,
-                            hostMgmtIp,
-                            localMgmtIp,
-                            dataIp,
-                            ovsdbPort,
-                            sshInfo,
-                            integrationBridgeId,
-                            dataIface,
-                            hostMgmtIface);
-    }
-
-    @Override
-    public String toString() {
-        return MoreObjects.toStringHelper(getClass())
-                .add("hostname", hostname)
-                .add("hostMgmtIp", hostMgmtIp)
-                .add("localMgmtIp", localMgmtIp)
-                .add("dataIp", dataIp)
-                .add("port", ovsdbPort)
-                .add("sshInfo", sshInfo)
-                .add("integrationBridgeId", integrationBridgeId)
-                .add("dataIface", dataIface)
-                .add("hostMgmtIface", hostMgmtIface)
-                .add("state", state)
-                .toString();
-    }
+    CordVtnNodeState state();
 
     /**
-     * Returns new node builder instance.
+     * Returns the identifier of the OVSDB device.
      *
-     * @return cordvtn node builder
+     * @return device id
      */
-    public static Builder builder() {
-        return new Builder();
-    }
+    DeviceId ovsdbId();
 
     /**
-     * Builder of node entities.
+     * Returns system interfaces of the node.
+     *
+     * @return set of interface names
      */
-    public static final class Builder {
-        private String hostname;
-        private CidrAddr hostMgmtIp;
-        private CidrAddr localMgmtIp;
-        private CidrAddr dataIp;
-        private Optional<TpPort> ovsdbPort =
-                Optional.of(TpPort.tpPort(DEFAULT_OVSDB_PORT));
-        private SshAccessInfo sshInfo;
-        private DeviceId integrationBridgeId;
-        private String dataIface;
-        private Optional<String> hostMgmtIface = Optional.empty();
-        private CordVtnNodeState state = CordVtnNodeState.noState();
+    Set<String> systemInterfaces();
 
-        private Builder() {
-        }
+    /**
+     * Builder of cordvtn node entities.
+     */
+    interface Builder {
 
         /**
-         * Builds an immutable cordvtn node.
+         * Returns new cordvtn node.
          *
          * @return cordvtn node
          */
-        public CordVtnNode build() {
-            // validate attributes
-            checkArgument(!Strings.isNullOrEmpty(hostname));
-            checkNotNull(hostMgmtIp);
-            checkNotNull(localMgmtIp);
-            checkNotNull(dataIp);
-            checkNotNull(ovsdbPort);
-            checkNotNull(sshInfo);
-            checkNotNull(integrationBridgeId);
-            checkNotNull(dataIface);
-            checkNotNull(hostMgmtIface);
-            return new CordVtnNode(hostname,
-                                   hostMgmtIp, localMgmtIp, dataIp,
-                                   ovsdbPort,
-                                   sshInfo,
-                                   integrationBridgeId,
-                                   dataIface,
-                                   hostMgmtIface,
-                                   state);
-        }
+        CordVtnNode build();
 
         /**
-         * Returns cordvtn node builder with hostname.
+         * Returns cordvtn node builder with the supplied hostname.
          *
-         * @param hostname hostname
+         * @param hostname hostname of the node
          * @return cordvtn node builder
          */
-        public Builder hostname(String hostname) {
-            checkArgument(!Strings.isNullOrEmpty(hostname));
-            this.hostname = hostname;
-            return this;
-        }
+        Builder hostname(String hostname);
 
         /**
-         * Returns cordvtn node builder with host management network IP address.
+         * Returns cordvtn node builder with the supplied host management IP.
          *
-         * @param hostMgmtIp host management netework ip address
+         * @param hostMgmtIp ip address with cidr notation
          * @return cordvtn node builder
          */
-        public Builder hostMgmtIp(CidrAddr hostMgmtIp) {
-            checkNotNull(hostMgmtIp);
-            this.hostMgmtIp = hostMgmtIp;
-            return this;
-        }
+        Builder hostManagementIp(CidrAddr hostMgmtIp);
 
         /**
-         * Returns cordvtn node builder with host management network IP address.
+         * Returns cordvtn node builder with the supplied local management IP.
          *
-         * @param cidr string value of the host management network ip address
+         * @param localMgmtIp ip address with cidr notation
          * @return cordvtn node builder
          */
-        public Builder hostMgmtIp(String cidr) {
-            this.hostMgmtIp = CidrAddr.valueOf(cidr);
-            return this;
-        }
+        // TODO remove this after dynamic provisioning of local management network
+        Builder localManagementIp(CidrAddr localMgmtIp);
 
         /**
-         * Returns cordvtn node builder with local management network IP address.
+         * Returns cordvtn node builder with the supplied data IP.
          *
-         * @param localMgmtIp local management network ip address
+         * @param dataIp ip address with cidr notation
          * @return cordvtn node builder
          */
-        public Builder localMgmtIp(CidrAddr localMgmtIp) {
-            checkNotNull(localMgmtIp);
-            this.localMgmtIp = localMgmtIp;
-            return this;
-        }
+        Builder dataIp(CidrAddr dataIp);
 
         /**
-         * Returns cordvtn node builder with local management netework IP address.
+         * Returns cordvtn node builder with the supplied integration bridge identifier.
          *
-         * @param cidr string value of the local management network ip address
+         * @param bridgeId bridge identifier
          * @return cordvtn node builder
          */
-        public Builder localMgmtIp(String cidr) {
-            this.localMgmtIp = CidrAddr.valueOf(cidr);
-            return this;
-        }
+        Builder integrationBridgeId(DeviceId bridgeId);
 
         /**
-         * Returns cordvtn node builder with data network IP address.
+         * Returns cordvtn node builder with the supplied data interface.
          *
-         * @param dataIp data network ip address
+         * @param dataIface interface name
          * @return cordvtn node builder
          */
-        public Builder dataIp(CidrAddr dataIp) {
-            checkNotNull(dataIp);
-            this.dataIp = dataIp;
-            return this;
-        }
+        Builder dataInterface(String dataIface);
 
         /**
-         * Returns cordvtn node builder with data network IP address.
+         * Returns cordvtn node builder with the supplied host management interface.
          *
-         * @param cidr string value of the data network ip address
+         * @param hostMgmtIface interface name
          * @return cordvtn node builder
          */
-        public Builder dataIp(String cidr) {
-            this.dataIp = CidrAddr.valueOf(cidr);
-            return this;
-        }
+        Builder hostManagementInterface(String hostMgmtIface);
 
         /**
-         * Returns cordvtn node builder with OVSDB server listen port number.
+         * Returns cordvtn node builder with the supplied OVSDB port.
          *
-         * @param port ovsdb server listen port number
+         * @param ovsdbPort transport layer port number
          * @return cordvtn node builder
          */
-        public Builder ovsdbPort(TpPort port) {
-            checkNotNull(port);
-            this.ovsdbPort = Optional.of(port);
-            return this;
-        }
+        Builder ovsdbPort(TpPort ovsdbPort);
 
         /**
-         * Returns cordvtn node builder with OVSDB server listen port number.
+         * Returns cordvtn node builder with the supplied SSH access information.
          *
-         * @param port int value of the ovsdb server listen port number
-         * @return cordvtn node builder
-         */
-        public Builder ovsdbPort(int port) {
-            this.ovsdbPort = Optional.of(TpPort.tpPort(port));
-            return this;
-        }
-
-        /**
-         * Returns cordvtn node builder with SSH access information.
          * @param sshInfo ssh access information
          * @return cordvtn node builder
          */
-        public Builder sshInfo(SshAccessInfo sshInfo) {
-            checkNotNull(sshInfo);
-            this.sshInfo = sshInfo;
-            return this;
-        }
+        Builder sshInfo(SshAccessInfo sshInfo);
 
         /**
-         * Returns cordvtn node builder with integration bridge ID.
+         * Returns cordvtn node builder with the supplied initialize state.
          *
-         * @param deviceId device id of the integration bridge
+         * @param state cordvtn node state
          * @return cordvtn node builder
          */
-        public Builder integrationBridgeId(DeviceId deviceId) {
-            checkNotNull(deviceId);
-            this.integrationBridgeId = deviceId;
-            return this;
-        }
-
-        /**
-         * Returns cordvtn node builder with integration bridge ID.
-         *
-         * @param deviceId string value of the integration bridge device id
-         * @return cordvtn node builder
-         */
-        public Builder integrationBridgeId(String deviceId) {
-            this.integrationBridgeId = DeviceId.deviceId(deviceId);
-            return this;
-        }
-
-        /**
-         * Returns cordvtn node builder with data network interface name.
-         *
-         * @param dataIface data network interface name
-         * @return cordvtn node builder
-         */
-        public Builder dataIface(String dataIface) {
-            checkArgument(!Strings.isNullOrEmpty(dataIface));
-            this.dataIface = dataIface;
-            return this;
-        }
-
-        /**
-         * Returns cordvtn node builder with host management network interface.
-         *
-         * @param hostMgmtIface host management network interface name
-         * @return cordvtn node builder
-         */
-        public Builder hostMgmtIface(String hostMgmtIface) {
-            this.hostMgmtIface = Optional.ofNullable(hostMgmtIface);
-            return this;
-        }
-
-        /**
-         * Returns cordvtn node builder with init state.
-         *
-         * @param state init state
-         * @return cordvtn node builder
-         */
-        public Builder state(CordVtnNodeState state) {
-            checkNotNull(state);
-            this.state = state;
-            return this;
-        }
+        Builder state(CordVtnNodeState state);
     }
 }
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeAdminService.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeAdminService.java
new file mode 100644
index 0000000..b312185
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeAdminService.java
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+/**
+ * Service for administering the inventory of {@link CordVtnNode}.
+ */
+public interface CordVtnNodeAdminService {
+
+    /**
+     * Creates a new node.
+     *
+     * @param node cordvtn node
+     */
+    void createNode(CordVtnNode node);
+
+    /**
+     * Updates the node.
+     *
+     * @param node cordvtn node
+     */
+    void updateNode(CordVtnNode node);
+
+    /**
+     * Removes the node with the supplied hostname.
+     *
+     * @param hostname hostname of the node
+     * @return removed node; null if it fails
+     */
+    CordVtnNode removeNode(String hostname);
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeEvent.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeEvent.java
new file mode 100644
index 0000000..3b6651f
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeEvent.java
@@ -0,0 +1,62 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+import org.onosproject.event.AbstractEvent;
+
+/**
+ * Describes cordvtn node events.
+ */
+public class CordVtnNodeEvent extends AbstractEvent<CordVtnNodeEvent.Type, CordVtnNode> {
+
+    public enum Type {
+
+        /**
+         * Signifies that the new node is created.
+         */
+        NODE_CREATED,
+
+        /**
+         * Signifies that the node is updated.
+         */
+        NODE_UPDATED,
+
+        /**
+         * Signifies that the node is removed.
+         */
+        NODE_REMOVED,
+
+        /**
+         * Signifies that the node state is changed to complete.
+         */
+        NODE_COMPLETE,
+
+        /**
+         * Signifies that the node state is changed to incomplete.
+         */
+        NODE_INCOMPLETE
+    }
+
+    /**
+     * Creates an event of a given type and the specified node.
+     *
+     * @param type cordvtn node event type
+     * @param node cordvtn node subject
+     */
+    public CordVtnNodeEvent(Type type, CordVtnNode node) {
+        super(type, node);
+    }
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeHandler.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeHandler.java
new file mode 100644
index 0000000..7dc1eb2
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeHandler.java
@@ -0,0 +1,50 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+/**
+ * Service providing cordvtn node bootstrapping.
+ */
+public interface CordVtnNodeHandler {
+
+    /**
+     * Processes the init state node.
+     *
+     * @param node cordvtn node
+     */
+    void processInitState(CordVtnNode node);
+
+    /**
+     * Processes the device created state node.
+     *
+     * @param node cordvtn node
+     */
+    void processDeviceCreatedState(CordVtnNode node);
+
+    /**
+     * Processes the port created state node.
+     *
+     * @param node cordvtn node
+     */
+    void processPortCreatedState(CordVtnNode node);
+
+    /**
+     * Processes the complete state node.
+     *
+     * @param node cordvtn node
+     */
+    void processCompleteState(CordVtnNode node);
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeListener.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeListener.java
new file mode 100644
index 0000000..91bd7ed
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeListener.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+import org.onosproject.event.EventListener;
+
+/**
+ * Listener for cordvtn node event.
+ */
+public interface CordVtnNodeListener extends EventListener<CordVtnNodeEvent> {
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeService.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeService.java
new file mode 100644
index 0000000..afa9b17
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeService.java
@@ -0,0 +1,57 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+import org.onosproject.event.ListenerService;
+import org.onosproject.net.DeviceId;
+
+import java.util.Set;
+
+/**
+ * Service for interfacing with the inventory of {@link CordVtnNode}.
+ */
+public interface CordVtnNodeService extends ListenerService<CordVtnNodeEvent, CordVtnNodeListener> {
+
+    /**
+     * Returns all nodes.
+     *
+     * @return set of nodes; empty set if no node presents
+     */
+    Set<CordVtnNode> nodes();
+
+    /**
+     * Returns nodes in complete state.
+     *
+     * @return set of nodes; empty set if no complete node presents
+     */
+    Set<CordVtnNode> completeNodes();
+
+    /**
+     * Returns the node with the given hostname.
+     *
+     * @param hostname hostname of the node
+     * @return cordvtn node; null if no node present with the hostname
+     */
+    CordVtnNode node(String hostname);
+
+    /**
+     * Returns the node with the given integration bridge device identifier.
+     *
+     * @param deviceId integration bridge device id
+     * @return cordvtn node; null if no node present with the device id
+     */
+    CordVtnNode node(DeviceId deviceId);
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeState.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeState.java
index e3d9cd5..49e02ff 100644
--- a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeState.java
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeState.java
@@ -18,13 +18,64 @@
 /**
  * Entity that defines possible init state of the cordvtn node.
  */
-public interface CordVtnNodeState {
+public enum CordVtnNodeState {
+
+    INIT {
+        @Override
+        public void process(CordVtnNodeHandler handler, CordVtnNode node) {
+            handler.processInitState(node);
+        }
+
+        @Override
+        public CordVtnNodeState nextState() {
+            return DEVICE_CREATED;
+        }
+    },
+    DEVICE_CREATED {
+        @Override
+        public void process(CordVtnNodeHandler handler, CordVtnNode node) {
+            handler.processDeviceCreatedState(node);
+        }
+
+        @Override
+        public CordVtnNodeState nextState() {
+            return PORT_CREATED;
+        }
+    },
+    PORT_CREATED {
+        @Override
+        public void process(CordVtnNodeHandler handler, CordVtnNode node) {
+            handler.processPortCreatedState(node);
+        }
+
+        @Override
+        public CordVtnNodeState nextState() {
+            return COMPLETE;
+        }
+    },
+    COMPLETE {
+        @Override
+        public void process(CordVtnNodeHandler handler, CordVtnNode node) {
+            handler.processCompleteState(node);
+        }
+
+        @Override
+        public CordVtnNodeState nextState() {
+            // last state
+            return COMPLETE;
+        }
+    };
+
     /**
-     * Returns null for no state.
+     * Processes the current node state to proceed to the next state.
      *
-     * @return null
+     * @param handler cordvtn node state handler
+     * @param node    cordvtn node
      */
-    static CordVtnNodeState noState() {
-        return null;
-    }
+    public abstract void process(CordVtnNodeHandler handler, CordVtnNode node);
+
+    /**
+     * Returns the next node state.
+     */
+    public abstract CordVtnNodeState nextState();
 }
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeStore.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeStore.java
new file mode 100644
index 0000000..d4626d5
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeStore.java
@@ -0,0 +1,63 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+import org.onosproject.store.Store;
+
+import java.util.Set;
+
+/**
+ * Manages the inventory of cordvtn nodes; not intended for direct use.
+ */
+public interface CordVtnNodeStore extends Store<CordVtnNodeEvent, CordVtnNodeStoreDelegate> {
+
+    /**
+     * Returns all nodes.
+     *
+     * @return set of nodes; empty set if no node presents
+     */
+    Set<CordVtnNode> nodes();
+
+    /**
+     * Returns the node with the given hostname.
+     *
+     * @param hostname hostname of the node
+     * @return cordvtn node; null if no node present with the hostname
+     */
+    CordVtnNode node(String hostname);
+
+    /**
+     * Creates a new node.
+     *
+     * @param node cordvtn node
+     */
+    void createNode(CordVtnNode node);
+
+    /**
+     * Updates the node.
+     *
+     * @param node cordvtn node
+     */
+    void updateNode(CordVtnNode node);
+
+    /**
+     * Removes the node with the supplied hostname.
+     *
+     * @param hostname hostname of the node
+     * @return removed node; null if it failed
+     */
+    CordVtnNode removeNode(String hostname);
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeStoreDelegate.java b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeStoreDelegate.java
new file mode 100644
index 0000000..366dea5
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/CordVtnNodeStoreDelegate.java
@@ -0,0 +1,24 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+import org.onosproject.store.StoreDelegate;
+
+/**
+ * CordVtn Node store delegate.
+ */
+public interface CordVtnNodeStoreDelegate extends StoreDelegate<CordVtnNodeEvent> {
+}
diff --git a/src/main/java/org/opencord/cordvtn/api/node/DeviceHandler.java b/src/main/java/org/opencord/cordvtn/api/node/DeviceHandler.java
new file mode 100644
index 0000000..b6e49c1
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/api/node/DeviceHandler.java
@@ -0,0 +1,66 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.api.node;
+
+import org.onosproject.net.Device;
+import org.onosproject.net.Port;
+
+/**
+ * Entity capable of handling a device state updates.
+ */
+public interface DeviceHandler {
+
+    /**
+     * Processes the connected device.
+     *
+     * @param device device
+     */
+    void connected(Device device);
+
+    /**
+     * Processes the disconnected device.
+     *
+     * @param device device.
+     */
+    void disconnected(Device device);
+
+    /**
+     * Processes newly added port.
+     *
+     * @param port port
+     */
+    default void portAdded(Port port) {
+        // do nothing by default
+    }
+
+    /**
+     * Processes the updated port.
+     *
+     * @param port port
+     */
+    default void portUpdated(Port port) {
+        // do nothing by default
+    }
+
+    /**
+     * Processes the removed port.
+     *
+     * @param port port
+     */
+    default void portRemoved(Port port) {
+        // do nothing by default
+    }
+}
diff --git a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeCheckCommand.java b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeCheckCommand.java
index 9e988ca..e3bd85d 100644
--- a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeCheckCommand.java
+++ b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeCheckCommand.java
@@ -23,7 +23,7 @@
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.Port;
 import org.opencord.cordvtn.api.node.CordVtnNode;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 import org.onosproject.net.Device;
 import org.onosproject.net.device.DeviceService;
 
@@ -44,18 +44,15 @@
             required = true, multiValued = false)
     private String hostname = null;
 
-    private static final String COMPLETE = "COMPLETE";
-    private static final String INCOMPLETE = "INCOMPLETE";
-    private static final String HINT = "hint: try init again if the state is INCOMPLETE" +
-            " but all settings OK";
+    private static final String HINT = "hint: try init again if the state is not" +
+            " COMPLETE but all settings are OK";
 
     @Override
     protected void execute() {
-        CordVtnNodeManager nodeManager = AbstractShellCommand.get(CordVtnNodeManager.class);
+        CordVtnNodeService nodeService = AbstractShellCommand.get(CordVtnNodeService.class);
         DeviceService deviceService = AbstractShellCommand.get(DeviceService.class);
 
-        CordVtnNode node = nodeManager.getNodes()
-                .stream()
+        CordVtnNode node = nodeService.nodes().stream()
                 .filter(n -> n.hostname().equals(hostname))
                 .findFirst()
                 .orElse(null);
@@ -64,7 +61,7 @@
             print("Cannot find %s from registered nodes", hostname);
             return;
         }
-        print("Current state: %s (%s)", getState(nodeManager, node), HINT);
+        print("Current state: %s (%s)", node.state().name(), HINT);
         print("%n[Integration Bridge Status]");
         Device device = deviceService.getDevice(node.integrationBridgeId());
         if (device != null) {
@@ -75,7 +72,7 @@
                   deviceService.isAvailable(device.id()),
                   device.annotations());
 
-            node.systemIfaces().stream().forEach(iface -> print(
+            node.systemInterfaces().forEach(iface -> print(
                     getPortState(deviceService, node.integrationBridgeId(), iface)));
         } else {
             print("%s %s=%s is not available",
@@ -89,7 +86,8 @@
         if (session != null) {
             Set<IpAddress> ips = getCurrentIps(session, INTEGRATION_BRIDGE);
             boolean isUp = isInterfaceUp(session, INTEGRATION_BRIDGE);
-            boolean isIp = ips.contains(node.dataIp().ip()) && ips.contains(node.localMgmtIp().ip());
+            boolean isIp = ips.contains(node.dataIp().ip()) &&
+                    ips.contains(node.localManagementIp().ip());
 
             print("%s %s up=%s Ips=%s",
                   isUp && isIp ? MSG_OK : MSG_NO,
@@ -97,9 +95,9 @@
                   isUp ? Boolean.TRUE : Boolean.FALSE,
                   getCurrentIps(session, INTEGRATION_BRIDGE));
 
-            print(getSystemIfaceState(session, node.dataIface()));
-            if (node.hostMgmtIface().isPresent()) {
-                print(getSystemIfaceState(session, node.hostMgmtIface().get()));
+            print(getSystemIfaceState(session, node.dataInterface()));
+            if (node.hostManagementInterface() != null) {
+                print(getSystemIfaceState(session, node.hostManagementInterface()));
             }
 
             disconnect(session);
@@ -108,7 +106,8 @@
         }
     }
 
-    private String getPortState(DeviceService deviceService, DeviceId deviceId, String portName) {
+    private String getPortState(DeviceService deviceService, DeviceId deviceId,
+                                String portName) {
         Port port = deviceService.getPorts(deviceId).stream()
                 .filter(p -> p.annotations().value(PORT_NAME).equals(portName) &&
                         p.isEnabled())
@@ -116,11 +115,11 @@
 
         if (port != null) {
             return String.format("%s %s portNum=%s enabled=%s %s",
-                                 port.isEnabled() ? MSG_OK : MSG_NO,
-                                 portName,
-                                 port.number(),
-                                 port.isEnabled() ? Boolean.TRUE : Boolean.FALSE,
-                                 port.annotations());
+                    port.isEnabled() ? MSG_OK : MSG_NO,
+                    portName,
+                    port.number(),
+                    port.isEnabled() ? Boolean.TRUE : Boolean.FALSE,
+                    port.annotations());
         } else {
             return String.format("%s %s does not exist", MSG_NO, portName);
         }
@@ -135,8 +134,4 @@
               isUp ? Boolean.TRUE : Boolean.FALSE,
               isIp ? Boolean.TRUE : Boolean.FALSE);
     }
-
-    private String getState(CordVtnNodeManager nodeManager, CordVtnNode node) {
-        return nodeManager.isNodeInitComplete(node) ? COMPLETE : INCOMPLETE;
-    }
 }
diff --git a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeDeleteCommand.java b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeDeleteCommand.java
index d098efe..eea9f44 100644
--- a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeDeleteCommand.java
+++ b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeDeleteCommand.java
@@ -19,11 +19,9 @@
 import org.apache.karaf.shell.commands.Argument;
 import org.apache.karaf.shell.commands.Command;
 import org.onosproject.cli.AbstractShellCommand;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
+import org.opencord.cordvtn.api.node.CordVtnNodeAdminService;
 import org.opencord.cordvtn.api.node.CordVtnNode;
 
-import java.util.NoSuchElementException;
-
 /**
  * Deletes nodes from the service.
  */
@@ -37,21 +35,14 @@
 
     @Override
     protected void execute() {
-        CordVtnNodeManager nodeManager = AbstractShellCommand.get(CordVtnNodeManager.class);
+        CordVtnNodeAdminService nodeAdminService =
+                AbstractShellCommand.get(CordVtnNodeAdminService.class);
 
         for (String hostname : hostnames) {
-            CordVtnNode node;
-            try {
-                node = nodeManager.getNodes()
-                        .stream()
-                        .filter(n -> n.hostname().equals(hostname))
-                        .findFirst().get();
-            } catch (NoSuchElementException e) {
+            CordVtnNode node = nodeAdminService.removeNode(hostname);
+            if (node == null) {
                 print("Unable to find %s", hostname);
-                continue;
             }
-
-            nodeManager.deleteNode(node);
         }
     }
 }
diff --git a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeInitCommand.java b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeInitCommand.java
index c7da215..1a2650e 100644
--- a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeInitCommand.java
+++ b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeInitCommand.java
@@ -19,10 +19,9 @@
 import org.apache.karaf.shell.commands.Argument;
 import org.apache.karaf.shell.commands.Command;
 import org.onosproject.cli.AbstractShellCommand;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
+import org.opencord.cordvtn.api.node.CordVtnNodeAdminService;
 import org.opencord.cordvtn.api.node.CordVtnNode;
-
-import java.util.NoSuchElementException;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 
 /**
  * Initializes nodes for CordVtn service.
@@ -37,21 +36,17 @@
 
     @Override
     protected void execute() {
-        CordVtnNodeManager nodeManager = AbstractShellCommand.get(CordVtnNodeManager.class);
+        CordVtnNodeService nodeService = AbstractShellCommand.get(CordVtnNodeService.class);
+        CordVtnNodeAdminService nodeAdminService =
+                AbstractShellCommand.get(CordVtnNodeAdminService.class);
 
         for (String hostname : hostnames) {
-            CordVtnNode node;
-            try {
-                node = nodeManager.getNodes()
-                        .stream()
-                        .filter(n -> n.hostname().equals(hostname))
-                        .findFirst().get();
-            } catch (NoSuchElementException e) {
+            CordVtnNode node = nodeService.node(hostname);
+            if (node == null) {
                 print("Unable to find %s", hostname);
-                continue;
+            } else {
+                nodeAdminService.updateNode(node);
             }
-
-            nodeManager.addOrUpdateNode(node);
         }
     }
 }
diff --git a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeListCommand.java b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeListCommand.java
index 7086a09..f1db3fb 100644
--- a/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeListCommand.java
+++ b/src/main/java/org/opencord/cordvtn/cli/CordVtnNodeListCommand.java
@@ -18,9 +18,10 @@
 import com.fasterxml.jackson.core.JsonProcessingException;
 import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.google.common.collect.Lists;
 import org.apache.karaf.shell.commands.Command;
 import org.onosproject.cli.AbstractShellCommand;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 import org.opencord.cordvtn.api.node.CordVtnNode;
 
 import java.util.Comparator;
@@ -35,19 +36,17 @@
         description = "Lists all nodes registered in CORD VTN service")
 public class CordVtnNodeListCommand extends AbstractShellCommand {
 
-    private static final String COMPLETE = "COMPLETE";
-    private static final String INCOMPLETE = "INCOMPLETE";
     private static final String FORMAT = "%-30s%-20s%-20s%-15s%-24s%s";
 
     @Override
     protected void execute() {
-        CordVtnNodeManager nodeManager = AbstractShellCommand.get(CordVtnNodeManager.class);
-        List<CordVtnNode> nodes = nodeManager.getNodes();
+        CordVtnNodeService nodeService = AbstractShellCommand.get(CordVtnNodeService.class);
+        List<CordVtnNode> nodes = Lists.newArrayList(nodeService.nodes());
         nodes.sort(Comparator.comparing(CordVtnNode::hostname));
 
         if (outputJson()) {
             try {
-                print("%s", mapper().writeValueAsString(json(nodeManager, nodes)));
+                print("%s", mapper().writeValueAsString(json(nodes)));
             } catch (JsonProcessingException e) {
                 print("Failed to list networks in JSON format");
             }
@@ -57,31 +56,27 @@
 
             for (CordVtnNode node : nodes) {
                 print(FORMAT, node.hostname(),
-                      node.hostMgmtIp().cidr(),
+                      node.hostManagementIp().cidr(),
                       node.dataIp().cidr(),
-                      node.dataIface(),
+                      node.dataInterface(),
                       node.integrationBridgeId().toString(),
-                      getState(nodeManager, node));
+                      node.state().name());
             }
-            print("Total %s nodes", nodeManager.getNodeCount());
+            print("Total %s nodes", nodes.size());
         }
     }
 
-    private JsonNode json(CordVtnNodeManager nodeManager, List<CordVtnNode> nodes) {
+    private JsonNode json(List<CordVtnNode> nodes) {
         ArrayNode result = mapper().enable(INDENT_OUTPUT).createArrayNode();
         for (CordVtnNode node : nodes) {
             result.add(mapper().createObjectNode()
                                .put("hostname", node.hostname())
-                               .put("managementIp", node.hostMgmtIp().cidr())
+                               .put("managementIp", node.hostManagementIp().cidr())
                                .put("dataIp", node.dataIp().cidr())
-                               .put("dataInterface", node.dataIface())
+                               .put("dataInterface", node.dataInterface())
                                .put("bridgeId", node.integrationBridgeId().toString())
-                               .put("state", getState(nodeManager, node)));
+                               .put("state", node.state().name()));
         }
         return result;
     }
-
-    private String getState(CordVtnNodeManager nodeManager, CordVtnNode node) {
-        return nodeManager.isNodeInitComplete(node) ? COMPLETE : INCOMPLETE;
-    }
 }
diff --git a/src/main/java/org/opencord/cordvtn/cli/CordVtnPurgeRulesCommand.java b/src/main/java/org/opencord/cordvtn/cli/CordVtnPurgeRulesCommand.java
index 06f5aee..e5a4ec5 100644
--- a/src/main/java/org/opencord/cordvtn/cli/CordVtnPurgeRulesCommand.java
+++ b/src/main/java/org/opencord/cordvtn/cli/CordVtnPurgeRulesCommand.java
@@ -17,7 +17,7 @@
 
 import org.apache.karaf.shell.commands.Command;
 import org.onosproject.cli.AbstractShellCommand;
-import org.opencord.cordvtn.impl.CordVtnPipeline;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
 
 /**
  * Purges all flow rules installed by CORD VTN service.
@@ -29,6 +29,6 @@
     @Override
     protected void execute() {
         CordVtnPipeline pipeline = AbstractShellCommand.get(CordVtnPipeline.class);
-        pipeline.flushRules();
+        pipeline.cleanupPipeline();
     }
 }
diff --git a/src/main/java/org/opencord/cordvtn/impl/CordVtnArpProxy.java b/src/main/java/org/opencord/cordvtn/impl/CordVtnArpProxy.java
index 4dc69a2..3d0c492 100644
--- a/src/main/java/org/opencord/cordvtn/impl/CordVtnArpProxy.java
+++ b/src/main/java/org/opencord/cordvtn/impl/CordVtnArpProxy.java
@@ -36,10 +36,13 @@
 import org.onosproject.core.CoreService;
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.Host;
+import org.onosproject.net.HostId;
+import org.onosproject.net.Port;
 import org.onosproject.net.PortNumber;
 import org.onosproject.net.config.NetworkConfigEvent;
 import org.onosproject.net.config.NetworkConfigListener;
 import org.onosproject.net.config.NetworkConfigService;
+import org.onosproject.net.device.DeviceService;
 import org.onosproject.net.flow.DefaultTrafficSelector;
 import org.onosproject.net.flow.DefaultTrafficTreatment;
 import org.onosproject.net.flow.TrafficSelector;
@@ -57,6 +60,8 @@
 import org.opencord.cordvtn.api.core.ServiceNetworkListener;
 import org.opencord.cordvtn.api.core.ServiceNetworkService;
 import org.opencord.cordvtn.api.net.ServiceNetwork;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 import org.osgi.service.component.ComponentContext;
 import org.slf4j.Logger;
 
@@ -68,6 +73,7 @@
 
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
+import static org.onosproject.net.AnnotationKeys.PORT_NAME;
 import static org.opencord.cordvtn.api.Constants.DEFAULT_GATEWAY_MAC_STR;
 import static org.opencord.cordvtn.api.net.ServiceNetwork.NetworkType.*;
 import static org.slf4j.LoggerFactory.getLogger;
@@ -97,7 +103,10 @@
     protected ComponentConfigService compConfigService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnNodeManager nodeManager;
+    protected DeviceService deviceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnNodeService nodeService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected ServiceNetworkService snetService;
@@ -303,13 +312,11 @@
 
     private void forwardManagementArpRequest(PacketContext context, Ethernet ethPacket) {
         DeviceId deviceId = context.inPacket().receivedFrom().deviceId();
-        PortNumber hostMgmtPort = nodeManager.hostManagementPort(deviceId);
-        Host host = hostService.getConnectedHosts(context.inPacket().receivedFrom())
-                .stream()
-                .findFirst().orElse(null);
+        PortNumber hostMgmtPort = hostMgmtPort(deviceId);
+        Host host = hostService.getHost(HostId.hostId(ethPacket.getSourceMAC()));
 
         if (host == null ||
-                !Instance.of(host).netType().name().contains("MANAGEMENT") ||
+                Instance.of(host).netType() != MANAGEMENT_HOST ||
                 hostMgmtPort == null) {
             context.block();
             return;
@@ -324,10 +331,22 @@
                 treatment,
                 ByteBuffer.wrap(ethPacket.serialize())));
 
-        log.trace("Forward ARP request to management network");
         context.block();
     }
 
+    private PortNumber hostMgmtPort(DeviceId deviceId) {
+        CordVtnNode node = nodeService.node(deviceId);
+        if (node == null || node.hostManagementInterface() == null) {
+            return null;
+        }
+        Optional<Port> port = deviceService.getPorts(deviceId).stream()
+                .filter(p -> p.annotations().value(PORT_NAME)
+                        .equals(node.hostManagementInterface()) &&
+                        p.isEnabled())
+                .findAny();
+        return port.isPresent() ? port.get().number() : null;
+    }
+
     /**
      * Emits gratuitous ARP when a gateway mac address has been changed.
      *
@@ -465,7 +484,7 @@
     private void readPublicGateways() {
         CordVtnConfig config = netConfigService.getConfig(appId, CordVtnConfig.class);
         if (config == null) {
-            log.debug("No configuration found");
+            log.warn("No configuration found");
             return;
         }
 
diff --git a/src/main/java/org/opencord/cordvtn/impl/CordVtnNodeManager.java b/src/main/java/org/opencord/cordvtn/impl/CordVtnNodeManager.java
index 97f5f77..14f96ea 100644
--- a/src/main/java/org/opencord/cordvtn/impl/CordVtnNodeManager.java
+++ b/src/main/java/org/opencord/cordvtn/impl/CordVtnNodeManager.java
@@ -16,99 +16,66 @@
 package org.opencord.cordvtn.impl;
 
 import com.google.common.base.Strings;
-import com.google.common.collect.Lists;
-import com.jcraft.jsch.Session;
+import com.google.common.collect.ImmutableSet;
 import org.apache.felix.scr.annotations.Activate;
 import org.apache.felix.scr.annotations.Component;
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
 import org.apache.felix.scr.annotations.Service;
-import org.onlab.packet.IpAddress;
-import org.onlab.util.KryoNamespace;
 import org.onosproject.cluster.ClusterService;
 import org.onosproject.cluster.LeadershipService;
 import org.onosproject.cluster.NodeId;
 import org.onosproject.core.ApplicationId;
 import org.onosproject.core.CoreService;
-import org.onosproject.net.ConnectPoint;
-import org.onosproject.net.Device;
+import org.onosproject.event.ListenerRegistry;
 import org.onosproject.net.DeviceId;
-import org.onosproject.net.Port;
-import org.onosproject.net.PortNumber;
-import org.onosproject.net.behaviour.BridgeConfig;
-import org.onosproject.net.behaviour.BridgeDescription;
-import org.onosproject.net.behaviour.BridgeName;
-import org.onosproject.net.behaviour.ControllerInfo;
-import org.onosproject.net.behaviour.DefaultBridgeDescription;
-import org.onosproject.net.behaviour.DefaultTunnelDescription;
-import org.onosproject.net.behaviour.InterfaceConfig;
-import org.onosproject.net.behaviour.TunnelDescription;
-import org.onosproject.net.behaviour.TunnelEndPoints;
-import org.onosproject.net.behaviour.TunnelKeys;
 import org.onosproject.net.config.NetworkConfigEvent;
 import org.onosproject.net.config.NetworkConfigListener;
 import org.onosproject.net.config.NetworkConfigService;
-import org.onosproject.net.device.DeviceAdminService;
-import org.onosproject.net.device.DeviceEvent;
-import org.onosproject.net.device.DeviceListener;
-import org.onosproject.net.device.DeviceService;
-import org.onosproject.net.host.HostService;
-import org.onosproject.ovsdb.controller.OvsdbClientService;
-import org.onosproject.ovsdb.controller.OvsdbController;
-import org.onosproject.ovsdb.controller.OvsdbNodeId;
-import org.onosproject.store.serializers.KryoNamespaces;
-import org.onosproject.store.service.ConsistentMap;
-import org.onosproject.store.service.MapEvent;
-import org.onosproject.store.service.MapEventListener;
-import org.onosproject.store.service.Serializer;
-import org.onosproject.store.service.StorageService;
-import org.onosproject.store.service.Versioned;
 import org.opencord.cordvtn.api.CordVtnConfig;
-import org.opencord.cordvtn.api.core.InstanceService;
-import org.opencord.cordvtn.api.net.CidrAddr;
-import org.opencord.cordvtn.api.node.ConnectionHandler;
 import org.opencord.cordvtn.api.node.CordVtnNode;
-import org.opencord.cordvtn.api.node.CordVtnNodeState;
-import org.opencord.cordvtn.api.node.SshAccessInfo;
+import org.opencord.cordvtn.api.node.CordVtnNodeAdminService;
+import org.opencord.cordvtn.api.node.CordVtnNodeEvent;
+import org.opencord.cordvtn.api.node.CordVtnNodeListener;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
+import org.opencord.cordvtn.api.node.CordVtnNodeStore;
+import org.opencord.cordvtn.api.node.CordVtnNodeStoreDelegate;
 import org.slf4j.Logger;
 
-import java.util.List;
 import java.util.Objects;
-import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ExecutorService;
 import java.util.stream.Collectors;
 
+import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
+import static java.lang.String.format;
 import static java.util.concurrent.Executors.newSingleThreadExecutor;
 import static org.onlab.util.Tools.groupedThreads;
-import static org.onosproject.net.AnnotationKeys.PORT_NAME;
-import static org.onosproject.net.Device.Type.SWITCH;
-import static org.onosproject.net.behaviour.TunnelDescription.Type.VXLAN;
 import static org.opencord.cordvtn.api.Constants.*;
-import static org.opencord.cordvtn.impl.RemoteIpCommandUtil.*;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.*;
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
- * Reads node information from the network config file and handles the config
- * update events.
- * Only a leader controller performs the node addition or deletion.
+ * Manages the inventory of the cordvtn nodes provided via network configuration.
  */
 @Component(immediate = true)
-@Service(value = CordVtnNodeManager.class)
-public class CordVtnNodeManager {
+@Service
+public class CordVtnNodeManager extends ListenerRegistry<CordVtnNodeEvent, CordVtnNodeListener>
+        implements CordVtnNodeAdminService, CordVtnNodeService {
 
     protected final Logger log = getLogger(getClass());
 
-    private static final KryoNamespace.Builder NODE_SERIALIZER = KryoNamespace.newBuilder()
-            .register(KryoNamespaces.API)
-            .register(CordVtnNode.class)
-            .register(NodeState.class)
-            .register(SshAccessInfo.class)
-            .register(CidrAddr.class);
+    private static final String MSG_NODE  = "Node %s %s";
+    private static final String MSG_CREATED = "created";
+    private static final String MSG_UPDATED = "updated";
+    private static final String MSG_REMOVED = "removed";
 
-    private static final int DPID_BEGIN = 3;
+    private static final String ERR_NULL_NODE = "CordVtn node cannot be null";
+    private static final String ERR_NULL_HOSTNAME = "CordVtn node hostname cannot be null";
+    private static final String ERR_NULL_DEVICE_ID = "Device ID cannot be null";
+    private static final String ERR_NOT_FOUND = "does not exist";
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected CoreService coreService;
@@ -117,114 +84,32 @@
     protected NetworkConfigService configService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected StorageService storageService;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected DeviceAdminService adminService;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected OvsdbController ovsdbController;
+    protected LeadershipService leadershipService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected ClusterService clusterService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected DeviceService deviceService;
+    protected CordVtnNodeStore nodeStore;
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected HostService hostService;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected LeadershipService leadershipService;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected InstanceService instanceService;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnPipeline pipeline;
-
-    private final ExecutorService eventExecutor =
-            newSingleThreadExecutor(groupedThreads("onos/cordvtn-node", "event-handler", log));
+    private final ExecutorService eventExecutor = newSingleThreadExecutor(
+            groupedThreads(this.getClass().getSimpleName(), "event-handler", log));
 
     private final NetworkConfigListener configListener = new InternalConfigListener();
-    private final DeviceListener deviceListener = new InternalDeviceListener();
-    private final MapEventListener<String, CordVtnNode> nodeStoreListener = new InternalMapListener();
+    private final CordVtnNodeStoreDelegate delegate = new InternalCordVtnNodeStoreDelegate();
 
-    private final OvsdbHandler ovsdbHandler = new OvsdbHandler();
-    private final BridgeHandler bridgeHandler = new BridgeHandler();
-
-    private ConsistentMap<String, CordVtnNode> nodeStore;
-    private List<ControllerInfo> controllers = Lists.newArrayList();
     private ApplicationId appId;
     private NodeId localNodeId;
 
-    private enum NodeState implements CordVtnNodeState {
-
-        INIT {
-            @Override
-            public void process(CordVtnNodeManager nodeManager, CordVtnNode node) {
-                // make sure there is OVSDB connection
-                if (!nodeManager.isOvsdbConnected(node)) {
-                    nodeManager.connectOvsdb(node);
-                    return;
-                }
-                nodeManager.createIntegrationBridge(node);
-            }
-        },
-        BRIDGE_CREATED {
-            @Override
-            public void process(CordVtnNodeManager nodeManager, CordVtnNode node) {
-                // make sure there is OVSDB connection
-                if (!nodeManager.isOvsdbConnected(node)) {
-                    nodeManager.connectOvsdb(node);
-                    return;
-                }
-
-                nodeManager.createTunnelInterface(node);
-                nodeManager.addSystemInterface(node, node.dataIface());
-                if (node.hostMgmtIface().isPresent()) {
-                    nodeManager.addSystemInterface(node, node.hostMgmtIface().get());
-                }
-            }
-        },
-        PORTS_ADDED {
-            @Override
-            public void process(CordVtnNodeManager nodeManager, CordVtnNode node) {
-                nodeManager.setIpAddress(node);
-            }
-        },
-        COMPLETE {
-            @Override
-            public void process(CordVtnNodeManager nodeManager, CordVtnNode node) {
-                nodeManager.postInit(node);
-            }
-        },
-        INCOMPLETE {
-            @Override
-            public void process(CordVtnNodeManager nodeManager, CordVtnNode node) {
-            }
-        };
-
-        public abstract void process(CordVtnNodeManager nodeManager, CordVtnNode node);
-    }
-
     @Activate
     protected void activate() {
         appId = coreService.registerApplication(CORDVTN_APP_ID);
         leadershipService.runForLeadership(appId.name());
         localNodeId = clusterService.getLocalNode().id();
 
-        nodeStore = storageService.<String, CordVtnNode>consistentMapBuilder()
-                .withSerializer(Serializer.using(NODE_SERIALIZER.build()))
-                .withName("cordvtn-nodestore")
-                .withApplicationId(appId)
-                .build();
-
-        nodeStore.addListener(nodeStoreListener, eventExecutor);
-        deviceService.addListener(deviceListener);
+        nodeStore.setDelegate(delegate);
         configService.addListener(configListener);
 
-        readControllers();
         readNodes();
         log.info("Started");
     }
@@ -232,8 +117,7 @@
     @Deactivate
     protected void deactivate() {
         configService.removeListener(configListener);
-        deviceService.removeListener(deviceListener);
-        nodeStore.removeListener(nodeStoreListener);
+        nodeStore.unsetDelegate(delegate);
 
         leadershipService.withdraw(appId.name());
         eventExecutor.shutdown();
@@ -241,611 +125,60 @@
         log.info("Stopped");
     }
 
-    /**
-     * Adds or updates a new node to the service.
-     *
-     * @param node cordvtn node
-     */
-    public void addOrUpdateNode(CordVtnNode node) {
-        checkNotNull(node);
-        nodeStore.put(node.hostname(), CordVtnNode.getUpdatedNode(node, getNodeState(node)));
+    @Override
+    public void createNode(CordVtnNode node) {
+        checkNotNull(node, ERR_NULL_NODE);
+        nodeStore.createNode(node);
+        log.info(format(MSG_NODE, node.hostname(), MSG_CREATED));
     }
 
-    /**
-     * Deletes a node from the service.
-     *
-     * @param node cordvtn node
-     */
-    public void deleteNode(CordVtnNode node) {
-        checkNotNull(node);
-        OvsdbClientService ovsdbClient = getOvsdbClient(node);
-        if (ovsdbClient != null && ovsdbClient.isConnected()) {
-            ovsdbClient.disconnect();
+    @Override
+    public void updateNode(CordVtnNode node) {
+        checkNotNull(node, ERR_NULL_NODE);
+        nodeStore.updateNode(node);
+        log.debug(format(MSG_NODE, node.hostname(), MSG_UPDATED));
+    }
+
+    @Override
+    public CordVtnNode removeNode(String hostname) {
+        checkArgument(!Strings.isNullOrEmpty(hostname), ERR_NULL_HOSTNAME);
+        CordVtnNode removed = nodeStore.removeNode(hostname);
+        if (removed == null) {
+            log.warn(format(MSG_NODE, hostname, ERR_NOT_FOUND));
+            return null;
         }
-        nodeStore.remove(node.hostname());
+        log.info(format(MSG_NODE, hostname, MSG_REMOVED));
+        return removed;
     }
 
-    /**
-     * Returns node initialization state.
-     *
-     * @param node cordvtn node
-     * @return true if initial node setup is completed, otherwise false
-     */
-    public boolean isNodeInitComplete(CordVtnNode node) {
-        checkNotNull(node);
-        return isNodeStateComplete(node);
+    @Override
+    public Set<CordVtnNode> nodes() {
+        return nodeStore.nodes();
     }
 
-    /**
-     * Returns the number of the nodes known to the service.
-     *
-     * @return number of nodes
-     */
-    public int getNodeCount() {
-        return nodeStore.size();
-    }
-
-    /**
-     * Returns all nodes known to the service.
-     *
-     * @return list of nodes
-     */
-    public List<CordVtnNode> getNodes() {
-        return nodeStore.values().stream().map(Versioned::value).collect(Collectors.toList());
-    }
-
-    /**
-     * Returns all nodes in complete state.
-     *
-     * @return set of nodes
-     */
+    @Override
     public Set<CordVtnNode> completeNodes() {
-        return getNodes().stream().filter(this::isNodeStateComplete)
-                .collect(Collectors.toSet());
-    }
-
-    /**
-     * Returns physical data plane port number of a given device.
-     *
-     * @param deviceId integration bridge device id
-     * @return port number; null otherwise
-     */
-    public PortNumber dataPort(DeviceId deviceId) {
-        CordVtnNode node = nodeByBridgeId(deviceId);
-        if (node == null) {
-            log.debug("Failed to get node for {}", deviceId);
-            return null;
-        }
-
-        Optional<PortNumber> port = getPortNumber(deviceId, node.dataIface());
-        return port.isPresent() ? port.get() : null;
-    }
-
-    /**
-     * Returns physical data plane IP address of a given device.
-     *
-     * @param deviceId integration bridge device id
-     * @return ip address; null otherwise
-     */
-    public IpAddress dataIp(DeviceId deviceId) {
-        CordVtnNode node = nodeByBridgeId(deviceId);
-        if (node == null) {
-            log.debug("Failed to get node for {}", deviceId);
-            return null;
-        }
-        return node.dataIp().ip();
-    }
-
-    /**
-     * Returns tunnel port number of a given device.
-     *
-     * @param deviceId integration bridge device id
-     * @return port number
-     */
-    public PortNumber tunnelPort(DeviceId deviceId) {
-        Optional<PortNumber> port = getPortNumber(deviceId, DEFAULT_TUNNEL);
-        return port.isPresent() ? port.get() : null;
-    }
-
-    /**
-     * Returns host management interface port number if exists.
-     *
-     * @param deviceId integration bridge device id
-     * @return port number; null if it does not exist
-     */
-    public PortNumber hostManagementPort(DeviceId deviceId) {
-        CordVtnNode node = nodeByBridgeId(deviceId);
-        if (node == null) {
-            log.debug("Failed to get node for {}", deviceId);
-            return null;
-        }
-
-        if (node.hostMgmtIface().isPresent()) {
-            Optional<PortNumber> port = getPortNumber(deviceId, node.hostMgmtIface().get());
-            return port.isPresent() ? port.get() : null;
-        } else {
-            return null;
-        }
-    }
-
-    private Optional<PortNumber> getPortNumber(DeviceId deviceId, String portName) {
-        PortNumber port = deviceService.getPorts(deviceId).stream()
-                .filter(p -> p.annotations().value(PORT_NAME).equals(portName) &&
-                        p.isEnabled())
-                .map(Port::number)
-                .findAny()
-                .orElse(null);
-        return Optional.ofNullable(port);
-    }
-
-    /**
-     * Returns if current node state saved in nodeStore is COMPLETE or not.
-     *
-     * @param node cordvtn node
-     * @return true if it's complete state, otherwise false
-     */
-    private boolean isNodeStateComplete(CordVtnNode node) {
-        checkNotNull(node);
-
         // the state saved in nodeStore can be wrong if IP address settings are changed
         // after the node init has been completed since there's no way to detect it
-        // getNodeState and checkNodeInitState always return correct answer but can be slow
-        Versioned<CordVtnNode> versionedNode = nodeStore.get(node.hostname());
-        CordVtnNodeState state = versionedNode.value().state();
-        return state != null && state.equals(NodeState.COMPLETE);
+        Set<CordVtnNode> nodes = nodes().stream()
+                .filter(node -> node.state() == COMPLETE)
+                .collect(Collectors.toSet());
+        return ImmutableSet.copyOf(nodes);
     }
 
-    /**
-     * Initiates node to serve virtual tenant network.
-     *
-     * @param node cordvtn node
-     */
-    private void initNode(CordVtnNode node) {
-        checkNotNull(node);
-
-        NodeState state = (NodeState) node.state();
-        log.debug("Processing node: {} state: {}", node.hostname(), state);
-
-        state.process(this, node);
+    @Override
+    public CordVtnNode node(String hostname) {
+        checkArgument(!Strings.isNullOrEmpty(hostname), ERR_NULL_HOSTNAME);
+        return nodeStore.node(hostname);
     }
 
-    /**
-     * Performs tasks after node initialization.
-     * It disconnects unnecessary OVSDB connection and installs initial flow
-     * rules on the device.
-     *
-     * @param node cordvtn node
-     */
-    private void postInit(CordVtnNode node) {
-        checkNotNull(node);
-
-        // disconnect OVSDB session once the node bootstrap is done
-        OvsdbClientService ovsdbClient = getOvsdbClient(node);
-        if (ovsdbClient != null && ovsdbClient.isConnected()) {
-            ovsdbClient.disconnect();
-        }
-
-        pipeline.initPipeline(node);
-
-        // adds existing instances to the host list
-        deviceService.getPorts(node.integrationBridgeId()).stream()
-                .filter(port -> !node.systemIfaces().contains(portName(port)) &&
-                        !port.number().equals(PortNumber.LOCAL) &&
-                        port.isEnabled())
-                .forEach(port -> instanceService.addInstance(connectPoint(port)));
-
-        // removes stale instances from the host list
-        hostService.getHosts().forEach(host -> {
-            if (deviceService.getPort(
-                    host.location().deviceId(),
-                    host.location().port()) == null) {
-                instanceService.removeInstance(host.location());
-            }
-        });
-
-        log.info("Finished init {}", node.hostname());
-    }
-
-    /**
-     * Sets a new state for a given cordvtn node.
-     *
-     * @param node cordvtn node
-     * @param newState new node state
-     */
-    private void setNodeState(CordVtnNode node, NodeState newState) {
-        checkNotNull(node);
-        log.debug("Changed {} state: {}", node.hostname(), newState);
-        nodeStore.put(node.hostname(), CordVtnNode.getUpdatedNode(node, newState));
-    }
-
-    /**
-     * Checks current state of a given cordvtn node and returns it.
-     *
-     * @param node cordvtn node
-     * @return node state
-     */
-    private NodeState getNodeState(CordVtnNode node) {
-        checkNotNull(node);
-        if (!isIntegrationBridgeCreated(node)) {
-            return NodeState.INIT;
-        }
-        for (String iface : node.systemIfaces()) {
-            if (!isIfaceCreated(node, iface)) {
-                return NodeState.BRIDGE_CREATED;
-            }
-        }
-        if (!isIpAddressSet(node)) {
-            return NodeState.PORTS_ADDED;
-        }
-        return NodeState.COMPLETE;
-    }
-
-    /**
-     * Returns connection state of OVSDB server for a given node.
-     *
-     * @param node cordvtn node
-     * @return true if it is connected, false otherwise
-     */
-    private boolean isOvsdbConnected(CordVtnNode node) {
-        checkNotNull(node);
-        OvsdbClientService ovsdbClient = getOvsdbClient(node);
-        return deviceService.isAvailable(node.ovsdbId()) &&
-                ovsdbClient != null &&
-                ovsdbClient.isConnected();
-    }
-
-    /**
-     * Connects to OVSDB server for a given node.
-     *
-     * @param node cordvtn node
-     */
-    private void connectOvsdb(CordVtnNode node) {
-        checkNotNull(node);
-        ovsdbController.connect(node.hostMgmtIp().ip(), node.ovsdbPort());
-    }
-
-    /**
-     * Returns OVSDB client for a given node.
-     *
-     * @param node cordvtn node
-     * @return ovsdb client, or null if there's no ovsdb connection
-     */
-    private OvsdbClientService getOvsdbClient(CordVtnNode node) {
-        checkNotNull(node);
-        OvsdbNodeId ovsdb = new OvsdbNodeId(
-                node.hostMgmtIp().ip(), node.ovsdbPort().toInt());
-        return ovsdbController.getOvsdbClient(ovsdb);
-    }
-
-    private void createIntegrationBridge(CordVtnNode node) {
-        Device device = deviceService.getDevice(node.ovsdbId());
-        if (device == null || !device.is(BridgeConfig.class)) {
-            log.error("Failed to create integration bridge on {}", node.ovsdbId());
-            return;
-        }
-
-        String dpid = node.integrationBridgeId().toString().substring(DPID_BEGIN);
-        BridgeDescription bridgeDesc = DefaultBridgeDescription.builder()
-                .name(INTEGRATION_BRIDGE)
-                .failMode(BridgeDescription.FailMode.SECURE)
-                .datapathId(dpid)
-                .disableInBand()
-                .controllers(controllers)
-                .build();
-
-        BridgeConfig bridgeConfig =  device.as(BridgeConfig.class);
-        bridgeConfig.addBridge(bridgeDesc);
-    }
-
-    private void createTunnelInterface(CordVtnNode node) {
-        Device device = deviceService.getDevice(node.ovsdbId());
-        if (device == null || !device.is(InterfaceConfig.class)) {
-            log.error("Failed to create tunnel interface on {}", node.ovsdbId());
-            return;
-        }
-
-        TunnelDescription tunnelDesc = DefaultTunnelDescription.builder()
-                .deviceId(INTEGRATION_BRIDGE)
-                .ifaceName(DEFAULT_TUNNEL)
-                .type(VXLAN)
-                .remote(TunnelEndPoints.flowTunnelEndpoint())
-                .key(TunnelKeys.flowTunnelKey())
-                .build();
-
-        InterfaceConfig ifaceConfig = device.as(InterfaceConfig.class);
-        ifaceConfig.addTunnelMode(DEFAULT_TUNNEL, tunnelDesc);
-    }
-
-    private void addSystemInterface(CordVtnNode node, String ifaceName) {
-        Session session = connect(node.sshInfo());
-        if (session == null || !isInterfaceUp(session, ifaceName)) {
-            log.warn("Interface {} is not available on {}", ifaceName, node.hostname());
-            disconnect(session);
-            return;
-        } else {
-            disconnect(session);
-        }
-
-        Device device = deviceService.getDevice(node.ovsdbId());
-        if (!device.is(BridgeConfig.class)) {
-            log.error("BridgeConfig is not supported for {}", node.ovsdbId());
-            return;
-        }
-
-        BridgeConfig bridgeConfig = device.as(BridgeConfig.class);
-        bridgeConfig.addPort(BridgeName.bridgeName(INTEGRATION_BRIDGE), ifaceName);
-    }
-
-    /**
-     * Flushes IP address from data plane interface and adds data plane IP address
-     * to integration bridge.
-     *
-     * @param node cordvtn node
-     */
-    private void setIpAddress(CordVtnNode node) {
-        Session session = connect(node.sshInfo());
-        if (session == null) {
-            log.debug("Failed to SSH to {}", node.hostname());
-            return;
-        }
-        getCurrentIps(session, INTEGRATION_BRIDGE).stream()
-                .filter(ip -> !ip.equals(node.localMgmtIp().ip()))
-                .filter(ip -> !ip.equals(node.dataIp().ip()))
-                .forEach(ip -> deleteIp(session, ip, INTEGRATION_BRIDGE));
-
-        boolean result = flushIp(session, node.dataIface()) &&
-                setInterfaceUp(session, node.dataIface()) &&
-                addIp(session, node.dataIp(), INTEGRATION_BRIDGE) &&
-                addIp(session, node.localMgmtIp(), INTEGRATION_BRIDGE) &&
-                setInterfaceUp(session, INTEGRATION_BRIDGE);
-
-        disconnect(session);
-        if (result) {
-            setNodeState(node, NodeState.COMPLETE);
-        }
-    }
-
-    private boolean isIntegrationBridgeCreated(CordVtnNode node) {
-        return deviceService.getDevice(node.integrationBridgeId()) != null &&
-                deviceService.isAvailable(node.integrationBridgeId());
-    }
-
-    private boolean isIfaceCreated(CordVtnNode node, String ifaceName) {
-        if (Strings.isNullOrEmpty(ifaceName)) {
-            return false;
-        }
-        return deviceService.getPorts(node.integrationBridgeId()).stream()
-                .anyMatch(p -> portName(p).contains(ifaceName) && p.isEnabled());
-    }
-
-    /**
-     * Checks if the IP addresses are correctly set.
-     *
-     * @param node cordvtn node
-     * @return true if the IP is set, false otherwise
-     */
-    private boolean isIpAddressSet(CordVtnNode node) {
-        Session session = connect(node.sshInfo());
-        if (session == null) {
-            log.debug("Failed to SSH to {}", node.hostname());
-            return false;
-        }
-
-        Set<IpAddress> intBrIps = getCurrentIps(session, INTEGRATION_BRIDGE);
-        boolean result = getCurrentIps(session, node.dataIface()).isEmpty() &&
-                isInterfaceUp(session, node.dataIface()) &&
-                intBrIps.contains(node.dataIp().ip()) &&
-                intBrIps.contains(node.localMgmtIp().ip()) &&
-                isInterfaceUp(session, INTEGRATION_BRIDGE);
-
-        disconnect(session);
-        return result;
-    }
-
-    /**
-     * Returns connect point of a given port.
-     *
-     * @param port port
-     * @return connect point
-     */
-    private ConnectPoint connectPoint(Port port) {
-        return new ConnectPoint(port.element().id(), port.number());
-    }
-
-    /**
-     * Returns cordvtn node associated with a given OVSDB device.
-     *
-     * @param ovsdbId OVSDB device id
-     * @return cordvtn node, null if it fails to find the node
-     */
-    private CordVtnNode nodeByOvsdbId(DeviceId ovsdbId) {
-        return getNodes().stream()
-                .filter(node -> node.ovsdbId().equals(ovsdbId))
-                .findFirst().orElse(null);
-    }
-
-    /**
-     * Returns cordvtn node associated with a given integration bridge.
-     *
-     * @param bridgeId device id of integration bridge
-     * @return cordvtn node, null if it fails to find the node
-     */
-    private CordVtnNode nodeByBridgeId(DeviceId bridgeId) {
-        return getNodes().stream()
-                .filter(node -> node.integrationBridgeId().equals(bridgeId))
-                .findFirst().orElse(null);
-    }
-
-    /**
-     * Returns port name.
-     *
-     * @param port port
-     * @return port name
-     */
-    private String portName(Port port) {
-        return port.annotations().value(PORT_NAME);
-    }
-
-    private class OvsdbHandler implements ConnectionHandler<Device> {
-
-        @Override
-        public void connected(Device device) {
-            CordVtnNode node = nodeByOvsdbId(device.id());
-            if (node != null) {
-                setNodeState(node, getNodeState(node));
-            } else {
-                log.info("{} is detected on unregistered node, ignore it.", device.id());
-            }
-        }
-
-        @Override
-        public void disconnected(Device device) {
-            log.debug("Device {} is disconnected", device.id());
-            adminService.removeDevice(device.id());
-        }
-    }
-
-    private class BridgeHandler implements ConnectionHandler<Device> {
-
-        @Override
-        public void connected(Device device) {
-            CordVtnNode node = nodeByBridgeId(device.id());
-            if (node != null) {
-                setNodeState(node, getNodeState(node));
-            } else {
-                log.info("{} is detected on unregistered node, ignore it.", device.id());
-            }
-        }
-
-        @Override
-        public void disconnected(Device device) {
-            CordVtnNode node = nodeByBridgeId(device.id());
-            if (node != null) {
-                log.warn("Integration Bridge is disconnected from {}", node.hostname());
-                setNodeState(node, NodeState.INCOMPLETE);
-            }
-        }
-
-        /**
-         * Handles port added situation.
-         * If the added port is tunnel or data plane interface, proceed to the remaining
-         * node initialization. Otherwise, do nothing.
-         *
-         * @param port port
-         */
-        public void portAdded(Port port) {
-            CordVtnNode node = nodeByBridgeId((DeviceId) port.element().id());
-            String portName = portName(port);
-            if (node == null) {
-                log.info("{} is added to unregistered node, ignore it.", portName);
-                return;
-            }
-
-            if (node.systemIfaces().contains(portName)) {
-                setNodeState(node, getNodeState(node));
-            } else if (isNodeStateComplete(node)) {
-                // TODO move this logic to InstanceManager
-                instanceService.addInstance(connectPoint(port));
-            } else {
-                log.warn("Instance is detected on incomplete node, ignore it.", portName);
-            }
-        }
-
-        /**
-         * Handles port removed situation.
-         * If the removed port is tunnel or data plane interface, proceed to the remaining
-         * node initialization.Others, do nothing.
-         *
-         * @param port port
-         */
-        public void portRemoved(Port port) {
-            CordVtnNode node = nodeByBridgeId((DeviceId) port.element().id());
-            String portName = portName(port);
-            if (node == null) {
-                log.info("{} is removed from unregistered node, ignore it.", portName);
-                return;
-            }
-
-            if (node.systemIfaces().contains(portName)) {
-                setNodeState(node, NodeState.INCOMPLETE);
-            } else if (isNodeStateComplete(node)) {
-                // TODO move this logic to InstanceManager
-                instanceService.removeInstance(connectPoint(port));
-            } else {
-                log.warn("VM is vanished from incomplete node, ignore it.", portName);
-            }
-        }
-    }
-
-    private class InternalDeviceListener implements DeviceListener {
-
-        @Override
-        public boolean isRelevant(DeviceEvent event) {
-            NodeId leaderNodeId = leadershipService.getLeader(appId.name());
-            return Objects.equals(localNodeId, leaderNodeId);
-        }
-
-        @Override
-        public void event(DeviceEvent event) {
-
-            Device device = event.subject();
-            ConnectionHandler<Device> handler = device.type().equals(SWITCH) ?
-                    bridgeHandler : ovsdbHandler;
-
-            switch (event.type()) {
-                case PORT_ADDED:
-                    eventExecutor.execute(() -> {
-                        log.info("Port {} is added to {}",
-                                 event.port().annotations().value(PORT_NAME),
-                                 event.subject().id());
-                        bridgeHandler.portAdded(event.port());
-                    });
-                    break;
-                case PORT_UPDATED:
-                    if (event.port().isEnabled()) {
-                        eventExecutor.execute(() -> {
-                            log.info("Port {} is added to {}",
-                                    event.port().annotations().value(PORT_NAME),
-                                    event.subject().id());
-                            bridgeHandler.portAdded(event.port());
-                        });
-                    } else {
-                        eventExecutor.execute(() -> {
-                            log.info("Port {} is removed from {}",
-                                    event.port().annotations().value(PORT_NAME),
-                                    event.subject().id());
-                            bridgeHandler.portRemoved(event.port());
-                        });
-                    }
-                    break;
-                case PORT_REMOVED:
-                    eventExecutor.execute(() -> {
-                        log.info("Port {} is removed from {}",
-                                event.port().annotations().value(PORT_NAME),
-                                event.subject().id());
-                        bridgeHandler.portRemoved(event.port());
-                    });
-                break;
-                case DEVICE_ADDED:
-                case DEVICE_AVAILABILITY_CHANGED:
-                    if (deviceService.isAvailable(device.id())) {
-                        eventExecutor.execute(() -> {
-                            log.info("Device {} is connected",
-                                     event.subject().id());
-                            handler.connected(device);
-                        });
-                    } else {
-                        eventExecutor.execute(() -> {
-                            log.info("Device {} is disconnected",
-                                     event.subject().id());
-                            handler.disconnected(device);
-                        });
-                    }
-                    break;
-                default:
-                    break;
-            }
-        }
+    @Override
+    public CordVtnNode node(DeviceId deviceId) {
+        checkNotNull(deviceId, ERR_NULL_DEVICE_ID);
+        return nodes().stream()
+                .filter(node -> node.integrationBridgeId().equals(deviceId) ||
+                        node.ovsdbId().equals(deviceId))
+                .findAny().orElse(null);
     }
 
     /**
@@ -860,21 +193,18 @@
 
         CordVtnConfig config = configService.getConfig(appId, CordVtnConfig.class);
         if (config == null) {
-            log.debug("No configuration found");
+            log.warn("No configuration found");
             return;
         }
-        config.cordVtnNodes().forEach(this::addOrUpdateNode);
-    }
-
-    private void readControllers() {
-        CordVtnConfig config = configService.getConfig(appId, CordVtnConfig.class);
-        if (config == null) {
-            log.debug("No configuration found");
-            return;
-        }
-        controllers = config.controllers();
-        controllers.forEach(ctrl -> {
-            log.debug("Added controller {}:{}", ctrl.ip(), ctrl.port());
+        config.cordVtnNodes().forEach(node -> {
+            log.info("Read node from network config: {}", node.hostname());
+            CordVtnNode existing = node(node.hostname());
+            if (existing == null) {
+                createNode(node);
+            } else if (!existing.equals(node)) {
+                // FIXME maybe we need to re-check node states
+                updateNode(node);
+            }
         });
     }
 
@@ -889,10 +219,7 @@
             switch (event.type()) {
                 case CONFIG_ADDED:
                 case CONFIG_UPDATED:
-                    eventExecutor.execute(() -> {
-                        readControllers();
-                        readNodes();
-                    });
+                    eventExecutor.execute(CordVtnNodeManager.this::readNodes);
                     break;
                 default:
                     break;
@@ -900,44 +227,12 @@
         }
     }
 
-    private class InternalMapListener implements MapEventListener<String, CordVtnNode> {
+    private class InternalCordVtnNodeStoreDelegate implements CordVtnNodeStoreDelegate {
 
         @Override
-        public void event(MapEvent<String, CordVtnNode> event) {
-            NodeId leaderNodeId = leadershipService.getLeader(appId.name());
-            if (!Objects.equals(localNodeId, leaderNodeId)) {
-                // do not allow to proceed without leadership
-                return;
-            }
-
-            CordVtnNode oldNode;
-            CordVtnNode newNode;
-
-            switch (event.type()) {
-            case UPDATE:
-                oldNode = event.oldValue().value();
-                newNode = event.newValue().value();
-
-                log.info("Reloaded {}", newNode.hostname());
-                if (!newNode.equals(oldNode)) {
-                    log.debug("New node: {}", newNode);
-                }
-                // performs init procedure even if the node is not changed
-                // for robustness since it's no harm to run init procedure
-                // multiple times
-                initNode(newNode);
-                break;
-            case INSERT:
-                newNode = event.newValue().value();
-                log.info("Added {}", newNode.hostname());
-                initNode(newNode);
-                break;
-            case REMOVE:
-                oldNode = event.oldValue().value();
-                log.info("Removed {}", oldNode.hostname());
-                break;
-            default:
-                break;
+        public void notify(CordVtnNodeEvent event) {
+            if (event != null) {
+                process(event);
             }
         }
     }
diff --git a/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnNode.java b/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnNode.java
new file mode 100644
index 0000000..e11e2d3
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnNode.java
@@ -0,0 +1,322 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Strings;
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Sets;
+import org.onlab.packet.TpPort;
+import org.onosproject.net.DeviceId;
+import org.opencord.cordvtn.api.net.CidrAddr;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeState;
+import org.opencord.cordvtn.api.node.SshAccessInfo;
+
+import java.util.Objects;
+import java.util.Set;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static com.google.common.base.Preconditions.checkNotNull;
+import static org.opencord.cordvtn.api.Constants.DEFAULT_OVSDB_PORT;
+import static org.opencord.cordvtn.api.Constants.DEFAULT_TUNNEL;
+
+/**
+ * Representation of a compute infrastructure node for CORD VTN service.
+ */
+public final class DefaultCordVtnNode implements CordVtnNode {
+
+    private final String hostname;
+    private final CidrAddr hostMgmtIp;
+    private final CidrAddr localMgmtIp;
+    private final CidrAddr dataIp;
+    private final DeviceId integrationBridgeId;
+    private final String dataIface;
+    private final String hostMgmtIface;
+    private final TpPort ovsdbPort;
+    private final SshAccessInfo sshInfo;
+    private final CordVtnNodeState state;
+
+    private DefaultCordVtnNode(String hostname,
+                               CidrAddr hostMgmtIp,
+                               CidrAddr localMgmtIp,
+                               CidrAddr dataIp,
+                               DeviceId integrationBridgeId,
+                               String dataIface,
+                               String hostMgmtIface,
+                               TpPort ovsdbPort,
+                               SshAccessInfo sshInfo,
+                               CordVtnNodeState state) {
+        this.hostname = hostname;
+        this.hostMgmtIp = hostMgmtIp;
+        this.localMgmtIp = localMgmtIp;
+        this.dataIp = dataIp;
+        this.integrationBridgeId = integrationBridgeId;
+        this.dataIface = dataIface;
+        this.hostMgmtIface = hostMgmtIface;
+        this.ovsdbPort = ovsdbPort;
+        this.sshInfo = sshInfo;
+        this.state = state;
+    }
+
+    /**
+     * Returns cordvtn node with the new state.
+     *
+     * @param node cordvtn node
+     * @param state cordvtn node state
+     * @return cordvtn node
+     */
+    public static CordVtnNode updatedState(CordVtnNode node, CordVtnNodeState state) {
+        return new DefaultCordVtnNode(node.hostname(),
+                node.hostManagementIp(),
+                node.localManagementIp(),
+                node.dataIp(),
+                node.integrationBridgeId(),
+                node.dataInterface(),
+                node.hostManagementInterface(),
+                node.ovsdbPort(),
+                node.sshInfo(),
+                state);
+    }
+
+    @Override
+    public String hostname() {
+        return this.hostname;
+    }
+
+    @Override
+    public CidrAddr hostManagementIp() {
+        return this.hostMgmtIp;
+    }
+
+    @Override
+    public CidrAddr localManagementIp() {
+        return this.localMgmtIp;
+    }
+
+    @Override
+    public CidrAddr dataIp() {
+        return this.dataIp;
+    }
+
+    @Override
+    public DeviceId integrationBridgeId() {
+        return this.integrationBridgeId;
+    }
+
+    @Override
+    public String dataInterface() {
+        return this.dataIface;
+    }
+
+    @Override
+    public String hostManagementInterface() {
+        return this.hostMgmtIface;
+    }
+
+    @Override
+    public TpPort ovsdbPort() {
+        return this.ovsdbPort;
+    }
+
+    @Override
+    public SshAccessInfo sshInfo() {
+        return this.sshInfo;
+    }
+
+    @Override
+    public CordVtnNodeState state() {
+        return this.state;
+    }
+
+    @Override
+    public DeviceId ovsdbId() {
+        return DeviceId.deviceId("ovsdb:" + this.hostMgmtIp.ip().toString());
+    }
+
+    @Override
+    public Set<String> systemInterfaces() {
+        Set<String> ifaces = Sets.newHashSet(DEFAULT_TUNNEL, dataIface);
+        if (hostMgmtIface != null) {
+            ifaces.add(hostMgmtIface);
+        }
+        return ImmutableSet.copyOf(ifaces);
+    }
+
+    @Override
+    public boolean equals(Object obj) {
+        if (this == obj) {
+            return true;
+        }
+
+        if (obj instanceof DefaultCordVtnNode) {
+            DefaultCordVtnNode that = (DefaultCordVtnNode) obj;
+            if (Objects.equals(hostname, that.hostname) &&
+                    Objects.equals(hostMgmtIp, that.hostMgmtIp) &&
+                    Objects.equals(localMgmtIp, that.localMgmtIp) &&
+                    Objects.equals(dataIp, that.dataIp) &&
+                    Objects.equals(integrationBridgeId, that.integrationBridgeId) &&
+                    Objects.equals(dataIface, that.dataIface) &&
+                    Objects.equals(hostMgmtIface, that.hostMgmtIface) &&
+                    Objects.equals(ovsdbPort, that.ovsdbPort) &&
+                    Objects.equals(sshInfo, that.sshInfo)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    @Override
+    public int hashCode() {
+        return Objects.hash(hostname,
+                hostMgmtIp,
+                localMgmtIp,
+                dataIp,
+                integrationBridgeId,
+                dataIface,
+                hostMgmtIface,
+                ovsdbPort,
+                sshInfo);
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(getClass())
+                .add("hostname", hostname)
+                .add("hostMgmtIp", hostMgmtIp)
+                .add("localMgmtIp", localMgmtIp)
+                .add("dataIp", dataIp)
+                .add("integrationBridgeId", integrationBridgeId)
+                .add("dataIface", dataIface)
+                .add("hostMgmtIface", hostMgmtIface)
+                .add("ovsdbPort", ovsdbPort)
+                .add("sshInfo", sshInfo)
+                .add("state", state)
+                .toString();
+    }
+
+    /**
+     * Returns new node builder instance.
+     *
+     * @return cordvtn node builder
+     */
+    public static Builder builder() {
+        return new Builder();
+    }
+
+    public static final class Builder implements CordVtnNode.Builder {
+
+        private String hostname;
+        private CidrAddr hostMgmtIp;
+        private CidrAddr localMgmtIp;
+        private CidrAddr dataIp;
+        private DeviceId integrationBridgeId;
+        private String dataIface;
+        private String hostMgmtIface;
+        private TpPort ovsdbPort = TpPort.tpPort(DEFAULT_OVSDB_PORT);
+        private SshAccessInfo sshInfo;
+        private CordVtnNodeState state = CordVtnNodeState.INIT;
+
+        private Builder() {
+        }
+
+        @Override
+        public CordVtnNode build() {
+            checkArgument(!Strings.isNullOrEmpty(hostname), "Hostname cannot be null");
+            checkNotNull(hostMgmtIp, "Host management IP address cannot be null");
+            checkNotNull(localMgmtIp, "Local management IP address cannot be null");
+            checkNotNull(dataIp, "Data IP address cannot be null");
+            checkNotNull(integrationBridgeId, "Integration bridge ID cannot be null");
+            checkArgument(!Strings.isNullOrEmpty(dataIface), "Data interface cannot be null");
+            if (hostMgmtIface != null) {
+                checkArgument(!Strings.isNullOrEmpty(hostMgmtIface),
+                        "Host management interface cannot be empty string");
+            }
+            checkNotNull(sshInfo, "SSH access information cannot be null");
+            checkNotNull(state, "Node state cannot be null");
+
+            return new DefaultCordVtnNode(hostname,
+                    hostMgmtIp,
+                    localMgmtIp,
+                    dataIp,
+                    integrationBridgeId,
+                    dataIface,
+                    hostMgmtIface,
+                    ovsdbPort,
+                    sshInfo, state);
+        }
+
+        @Override
+        public Builder hostname(String hostname) {
+            this.hostname = hostname;
+            return this;
+        }
+
+        @Override
+        public Builder hostManagementIp(CidrAddr hostMgmtIp) {
+            this.hostMgmtIp = hostMgmtIp;
+            return this;
+        }
+
+        @Override
+        public Builder localManagementIp(CidrAddr localMgmtIp) {
+            this.localMgmtIp = localMgmtIp;
+            return this;
+        }
+
+        @Override
+        public Builder dataIp(CidrAddr dataIp) {
+            this.dataIp = dataIp;
+            return this;
+        }
+
+        @Override
+        public Builder integrationBridgeId(DeviceId deviceId) {
+            this.integrationBridgeId = deviceId;
+            return this;
+        }
+
+        @Override
+        public Builder dataInterface(String dataIface) {
+            this.dataIface = dataIface;
+            return this;
+        }
+
+        @Override
+        public Builder hostManagementInterface(String hostMgmtIface) {
+            this.hostMgmtIface = hostMgmtIface;
+            return this;
+        }
+
+        @Override
+        public Builder ovsdbPort(TpPort port) {
+            this.ovsdbPort = port;
+            return this;
+        }
+
+        @Override
+        public Builder sshInfo(SshAccessInfo sshInfo) {
+            this.sshInfo = sshInfo;
+            return this;
+        }
+
+        @Override
+        public Builder state(CordVtnNodeState state) {
+            this.state = state;
+            return this;
+        }
+    }
+}
diff --git a/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeHandler.java b/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeHandler.java
new file mode 100644
index 0000000..a663e38
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeHandler.java
@@ -0,0 +1,601 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.ImmutableSet;
+import com.jcraft.jsch.Session;
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.packet.IpAddress;
+import org.onosproject.cluster.ClusterService;
+import org.onosproject.cluster.LeadershipService;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Port;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.behaviour.BridgeConfig;
+import org.onosproject.net.behaviour.BridgeDescription;
+import org.onosproject.net.behaviour.BridgeName;
+import org.onosproject.net.behaviour.ControllerInfo;
+import org.onosproject.net.behaviour.DefaultBridgeDescription;
+import org.onosproject.net.behaviour.DefaultTunnelDescription;
+import org.onosproject.net.behaviour.InterfaceConfig;
+import org.onosproject.net.behaviour.TunnelDescription;
+import org.onosproject.net.behaviour.TunnelEndPoints;
+import org.onosproject.net.behaviour.TunnelKeys;
+import org.onosproject.net.config.NetworkConfigEvent;
+import org.onosproject.net.config.NetworkConfigListener;
+import org.onosproject.net.config.NetworkConfigService;
+import org.onosproject.net.device.DeviceAdminService;
+import org.onosproject.net.device.DeviceEvent;
+import org.onosproject.net.device.DeviceListener;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.host.HostService;
+import org.onosproject.ovsdb.controller.OvsdbClientService;
+import org.onosproject.ovsdb.controller.OvsdbController;
+import org.onosproject.ovsdb.controller.OvsdbNodeId;
+import org.opencord.cordvtn.api.CordVtnConfig;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
+import org.opencord.cordvtn.api.core.InstanceService;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeAdminService;
+import org.opencord.cordvtn.api.node.CordVtnNodeEvent;
+import org.opencord.cordvtn.api.node.CordVtnNodeHandler;
+import org.opencord.cordvtn.api.node.CordVtnNodeListener;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
+import org.opencord.cordvtn.api.node.CordVtnNodeState;
+import org.opencord.cordvtn.api.node.DeviceHandler;
+import org.slf4j.Logger;
+
+import java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import java.util.concurrent.ExecutorService;
+import java.util.stream.Collectors;
+
+import static java.lang.String.format;
+import static java.util.concurrent.Executors.newSingleThreadExecutor;
+import static org.onlab.util.Tools.groupedThreads;
+import static org.onosproject.net.AnnotationKeys.PORT_NAME;
+import static org.onosproject.net.Device.Type.SWITCH;
+import static org.onosproject.net.behaviour.TunnelDescription.Type.VXLAN;
+import static org.opencord.cordvtn.api.Constants.CORDVTN_APP_ID;
+import static org.opencord.cordvtn.api.Constants.DEFAULT_TUNNEL;
+import static org.opencord.cordvtn.api.Constants.INTEGRATION_BRIDGE;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.*;
+import static org.opencord.cordvtn.impl.DefaultCordVtnNode.updatedState;
+import static org.opencord.cordvtn.impl.RemoteIpCommandUtil.*;
+import static org.opencord.cordvtn.impl.RemoteIpCommandUtil.disconnect;
+import static org.opencord.cordvtn.impl.RemoteIpCommandUtil.isInterfaceUp;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Implementation of the {@link CordVtnNodeHandler} with OVSDB and SSH exec channel.
+ */
+@Component(immediate = true)
+@Service
+public class DefaultCordVtnNodeHandler implements CordVtnNodeHandler {
+
+    protected final Logger log = getLogger(getClass());
+
+    private static final String ERR_INCOMPLETE = "%s is %s from incomplete node, ignore it";
+    private static final String ERR_UNREGISTERED = "%s is %s from unregistered node, ignore it";
+    private static final String ERR_DETECTED = "detected";
+    private static final String ERR_VANISHED = "vanished";
+
+    private static final int DPID_BEGIN = 3;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected LeadershipService leadershipService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ClusterService clusterService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected NetworkConfigService configService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DeviceService deviceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DeviceAdminService deviceAdminService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected HostService hostService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected OvsdbController ovsdbController;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnNodeService nodeService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnNodeAdminService nodeAdminService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected InstanceService instanceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnPipeline pipelineService;
+
+    private final ExecutorService eventExecutor = newSingleThreadExecutor(
+            groupedThreads(this.getClass().getSimpleName(), "event-handler", log));
+    private final NetworkConfigListener configListener = new InternalConfigListener();
+    private final DeviceListener deviceListener = new InternalDeviceListener();
+    private final DeviceHandler ovsdbHandler = new OvsdbDeviceHandler();
+    private final DeviceHandler intgBridgeHandler = new IntegrationBridgeDeviceHandler();
+    private final CordVtnNodeListener nodeListener = new InternalCordVtnNodeListener();
+
+    private ApplicationId appId;
+    private NodeId localNodeId;
+    private List<ControllerInfo> controllers = ImmutableList.of();
+
+    @Activate
+    protected void activate() {
+        appId = coreService.registerApplication(CORDVTN_APP_ID);
+        leadershipService.runForLeadership(appId.name());
+        localNodeId = clusterService.getLocalNode().id();
+
+        configService.addListener(configListener);
+        deviceService.addListener(deviceListener);
+        nodeService.addListener(nodeListener);
+
+        readControllers();
+        log.info("Started");
+    }
+
+    @Deactivate
+    protected void deactivate() {
+        nodeService.removeListener(nodeListener);
+        deviceService.removeListener(deviceListener);
+        configService.removeListener(configListener);
+
+        leadershipService.withdraw(appId.name());
+        eventExecutor.shutdown();
+
+        log.info("Stopped");
+    }
+
+    @Override
+    public void processInitState(CordVtnNode node) {
+        if (!isOvsdbConnected(node)) {
+            ovsdbController.connect(node.hostManagementIp().ip(), node.ovsdbPort());
+            return;
+        }
+        createIntegrationBridge(node);
+    }
+
+    @Override
+    public void processDeviceCreatedState(CordVtnNode node) {
+        if (!isOvsdbConnected(node)) {
+            ovsdbController.connect(node.hostManagementIp().ip(), node.ovsdbPort());
+            return;
+        }
+        createTunnelInterface(node);
+        addSystemInterface(node, node.dataInterface());
+        if (node.hostManagementInterface() != null) {
+            addSystemInterface(node, node.hostManagementInterface());
+        }
+    }
+
+    @Override
+    public void processPortCreatedState(CordVtnNode node) {
+        configureInterface(node);
+    }
+
+    @Override
+    public void processCompleteState(CordVtnNode node) {
+        OvsdbClientService ovsdbClient = ovsdbController.getOvsdbClient(
+                new OvsdbNodeId(
+                        node.hostManagementIp().ip(),
+                        node.ovsdbPort().toInt()));
+        if (ovsdbClient != null && ovsdbClient.isConnected()) {
+            ovsdbClient.disconnect();
+        }
+        // TODO fix postInit to be done in the proper services
+        postInit(node);
+        log.info("Finished init {}", node.hostname());
+    }
+
+    private boolean isOvsdbConnected(CordVtnNode node) {
+        OvsdbClientService ovsdbClient = ovsdbController.getOvsdbClient(
+                new OvsdbNodeId(
+                        node.hostManagementIp().ip(),
+                        node.ovsdbPort().toInt()));
+        return deviceService.isAvailable(node.ovsdbId()) && ovsdbClient != null &&
+                ovsdbClient.isConnected();
+    }
+
+    private void createIntegrationBridge(CordVtnNode node) {
+        Device device = deviceService.getDevice(node.ovsdbId());
+        if (device == null || !device.is(BridgeConfig.class)) {
+            log.error("Failed to create integration bridge on {}", node.ovsdbId());
+            return;
+        }
+        String dpid = node.integrationBridgeId().toString().substring(DPID_BEGIN);
+        BridgeDescription bridgeDesc = DefaultBridgeDescription.builder()
+                .name(INTEGRATION_BRIDGE)
+                .failMode(BridgeDescription.FailMode.SECURE)
+                .datapathId(dpid)
+                .disableInBand()
+                .controllers(controllers)
+                .build();
+
+        BridgeConfig bridgeConfig = device.as(BridgeConfig.class);
+        bridgeConfig.addBridge(bridgeDesc);
+    }
+
+    private void createTunnelInterface(CordVtnNode node) {
+        Device device = deviceService.getDevice(node.ovsdbId());
+        if (device == null || !device.is(InterfaceConfig.class)) {
+            log.error("Failed to create tunnel interface on {}", node.ovsdbId());
+            return;
+        }
+        TunnelDescription tunnelDesc = DefaultTunnelDescription.builder()
+                .deviceId(INTEGRATION_BRIDGE)
+                .ifaceName(DEFAULT_TUNNEL)
+                .type(VXLAN)
+                .remote(TunnelEndPoints.flowTunnelEndpoint())
+                .key(TunnelKeys.flowTunnelKey())
+                .build();
+
+        InterfaceConfig ifaceConfig = device.as(InterfaceConfig.class);
+        ifaceConfig.addTunnelMode(DEFAULT_TUNNEL, tunnelDesc);
+    }
+
+    private void addSystemInterface(CordVtnNode node, String ifaceName) {
+        Session session = connect(node.sshInfo());
+        if (session == null || !isInterfaceUp(session, ifaceName)) {
+            log.error("Interface {} is not available on {}", ifaceName, node.hostname());
+            disconnect(session);
+            return;
+        } else {
+            disconnect(session);
+        }
+
+        Device device = deviceService.getDevice(node.ovsdbId());
+        if (!device.is(BridgeConfig.class)) {
+            log.error("BridgeConfig is not supported for {}", node.ovsdbId());
+            return;
+        }
+
+        BridgeConfig bridgeConfig = device.as(BridgeConfig.class);
+        bridgeConfig.addPort(BridgeName.bridgeName(INTEGRATION_BRIDGE), ifaceName);
+    }
+
+    private void configureInterface(CordVtnNode node) {
+        Session session = connect(node.sshInfo());
+        if (session == null) {
+            log.error("Failed to SSH to {}", node.hostname());
+            return;
+        }
+        getCurrentIps(session, INTEGRATION_BRIDGE).stream()
+                .filter(ip -> !ip.equals(node.localManagementIp().ip()))
+                .filter(ip -> !ip.equals(node.dataIp().ip()))
+                .forEach(ip -> deleteIp(session, ip, INTEGRATION_BRIDGE));
+
+        final boolean result = flushIp(session, node.dataInterface()) &&
+                setInterfaceUp(session, node.dataInterface()) &&
+                addIp(session, node.dataIp(), INTEGRATION_BRIDGE) &&
+                addIp(session, node.localManagementIp(), INTEGRATION_BRIDGE) &&
+                setInterfaceUp(session, INTEGRATION_BRIDGE);
+
+        disconnect(session);
+        if (result) {
+            bootstrapNode(node);
+        }
+    }
+
+    private void postInit(CordVtnNode node) {
+        // TODO move the below line to DefaultCordVtnPipeline
+        pipelineService.initPipeline(node);
+
+        // TODO move the logic below to InstanceManager
+        // adds existing instances to the host list
+        deviceService.getPorts(node.integrationBridgeId()).stream()
+                .filter(port -> port.isEnabled() &&
+                        !port.number().equals(PortNumber.LOCAL) &&
+                        !node.systemInterfaces().contains(port.annotations().value(PORT_NAME)))
+                .forEach(port -> instanceService.addInstance(new ConnectPoint(
+                        port.element().id(),
+                        port.number()
+                )));
+        // removes stale instances from the host list
+        hostService.getHosts().forEach(host -> {
+            if (deviceService.getPort(
+                    host.location().deviceId(),
+                    host.location().port()) == null) {
+                instanceService.removeInstance(host.location());
+            }
+        });
+    }
+
+    private class OvsdbDeviceHandler implements DeviceHandler {
+
+        @Override
+        public void connected(Device device) {
+            CordVtnNode node = nodeService.node(device.id());
+            if (node != null) {
+                bootstrapNode(node);
+            }
+        }
+
+        @Override
+        public void disconnected(Device device) {
+            CordVtnNode node = nodeService.node(device.id());
+            if (node != null && node.state() == COMPLETE) {
+                log.debug("Device({}) from {} disconnected", device.id(), node.hostname());
+                deviceAdminService.removeDevice(device.id());
+            }
+        }
+    }
+
+    private class IntegrationBridgeDeviceHandler implements DeviceHandler {
+
+        @Override
+        public void connected(Device device) {
+            CordVtnNode node = nodeService.node(device.id());
+            if (node != null) {
+                bootstrapNode(node);
+            }
+        }
+
+        @Override
+        public void disconnected(Device device) {
+            CordVtnNode node = nodeService.node(device.id());
+            if (node != null) {
+                log.warn("Device({}) from {} disconnected", device.id(), node.hostname());
+                setState(node, INIT);
+            }
+        }
+
+        @Override
+        public void portAdded(Port port) {
+            CordVtnNode node = nodeService.node((DeviceId) port.element().id());
+            String portName = port.annotations().value(PORT_NAME);
+            if (node == null) {
+                log.warn(format(ERR_UNREGISTERED, portName, ERR_DETECTED));
+                return;
+            }
+            if (node.systemInterfaces().contains(portName)) {
+                if (node.state() == DEVICE_CREATED) {
+                    bootstrapNode(node);
+                }
+            } else if (node.state() == COMPLETE) {
+                // TODO move this logic to InstanceManager
+                instanceService.addInstance(new ConnectPoint(port.element().id(),
+                        port.number()));
+            } else {
+                log.warn(format(ERR_INCOMPLETE, portName, ERR_DETECTED));
+            }
+        }
+
+        @Override
+        public void portRemoved(Port port) {
+            CordVtnNode node = nodeService.node((DeviceId) port.element().id());
+            String portName = port.annotations().value(PORT_NAME);
+            if (node == null) {
+                log.warn(format(ERR_UNREGISTERED, portName, ERR_VANISHED));
+                return;
+            }
+            if (node.systemInterfaces().contains(portName)) {
+                if (node.state() == PORT_CREATED || node.state() == COMPLETE) {
+                    // always falls back to INIT state to avoid a mess caused by
+                    // the multiple events received out of order
+                    setState(node, INIT);
+                }
+            } else if (node.state() == COMPLETE) {
+                // TODO move this logic to InstanceManager
+                instanceService.removeInstance(new ConnectPoint(port.element().id(),
+                        port.number()));
+            } else {
+                log.warn(format(ERR_INCOMPLETE, portName, ERR_VANISHED));
+            }
+        }
+    }
+
+    private class InternalDeviceListener implements DeviceListener {
+
+        @Override
+        public void event(DeviceEvent event) {
+            eventExecutor.execute(() -> {
+                NodeId leader = leadershipService.getLeader(appId.name());
+                if (!Objects.equals(localNodeId, leader)) {
+                    // do not allow to proceed without leadership
+                    return;
+                }
+                handle(event);
+            });
+        }
+
+        private void handle(DeviceEvent event) {
+            DeviceHandler handler = event.subject().type().equals(SWITCH) ?
+                    intgBridgeHandler : ovsdbHandler;
+            Device device = event.subject();
+
+            switch (event.type()) {
+                case DEVICE_AVAILABILITY_CHANGED:
+                case DEVICE_ADDED:
+                    if (deviceService.isAvailable(device.id())) {
+                        log.debug("Device {} is connected", device.id());
+                        handler.connected(device);
+                    } else {
+                        log.debug("Device {} is disconnected", device.id());
+                        handler.disconnected(device);
+                    }
+                    break;
+                case PORT_ADDED:
+                    log.debug("Port {} is added to {}",
+                            event.port().annotations().value(PORT_NAME),
+                            device.id());
+                    handler.portAdded(event.port());
+                    break;
+                case PORT_UPDATED:
+                    if (event.port().isEnabled()) {
+                        log.debug("Port {} is added to {}",
+                                event.port().annotations().value(PORT_NAME),
+                                device.id());
+                        handler.portAdded(event.port());
+                    } else {
+                        log.debug("Port {} is removed from {}",
+                                event.port().annotations().value(PORT_NAME),
+                                device.id());
+                        handler.portRemoved(event.port());
+                    }
+                    break;
+                case PORT_REMOVED:
+                    log.debug("Port {} is removed from {}",
+                            event.port().annotations().value(PORT_NAME),
+                            device.id());
+                    handler.portRemoved(event.port());
+                    break;
+                default:
+                    break;
+            }
+        }
+    }
+
+    private Set<String> activePorts(DeviceId deviceId) {
+        Set<String> activePorts = deviceService.getPorts(deviceId).stream()
+                .filter(Port::isEnabled)
+                .map(port -> port.annotations().value(PORT_NAME))
+                .collect(Collectors.toSet());
+        return ImmutableSet.copyOf(activePorts);
+    }
+
+    private boolean isIpAddressSet(CordVtnNode node) {
+        Session session = connect(node.sshInfo());
+        if (session == null) {
+            log.warn("Failed to SSH to {}", node.hostname());
+            return false;
+        }
+        Set<IpAddress> intBrIps = getCurrentIps(session, INTEGRATION_BRIDGE);
+        boolean result = getCurrentIps(session, node.dataInterface()).isEmpty() &&
+                isInterfaceUp(session, node.dataInterface()) &&
+                intBrIps.contains(node.dataIp().ip()) &&
+                intBrIps.contains(node.localManagementIp().ip()) &&
+                isInterfaceUp(session, INTEGRATION_BRIDGE);
+
+        disconnect(session);
+        return result;
+    }
+
+    private boolean isCurrentStateDone(CordVtnNode node) {
+        switch (node.state()) {
+            case INIT:
+                return deviceService.isAvailable(node.integrationBridgeId());
+            case DEVICE_CREATED:
+                Set<String> activePorts = activePorts(node.integrationBridgeId());
+                return node.systemInterfaces().stream().allMatch(activePorts::contains);
+            case PORT_CREATED:
+                return isIpAddressSet(node);
+            case COMPLETE:
+                return false;
+            default:
+                return false;
+        }
+    }
+
+    private void setState(CordVtnNode node, CordVtnNodeState newState) {
+        if (node.state() == newState) {
+            return;
+        }
+        CordVtnNode updated = updatedState(node, newState);
+        nodeAdminService.updateNode(updated);
+        log.info("Changed {} state: {}", node.hostname(), newState);
+    }
+
+    private void bootstrapNode(CordVtnNode node) {
+        if (isCurrentStateDone(node)) {
+            setState(node, node.state().nextState());
+        } else {
+            node.state().process(this, node);
+        }
+    }
+
+    private class InternalCordVtnNodeListener implements CordVtnNodeListener {
+
+        @Override
+        public void event(CordVtnNodeEvent event) {
+            eventExecutor.execute(() -> {
+                NodeId leader = leadershipService.getLeader(appId.name());
+                if (!Objects.equals(localNodeId, leader)) {
+                    // do not allow to proceed without leadership
+                    return;
+                }
+                handle(event);
+            });
+        }
+
+        private void handle(CordVtnNodeEvent event) {
+            switch (event.type()) {
+                case NODE_CREATED:
+                case NODE_UPDATED:
+                    bootstrapNode(event.subject());
+                    break;
+                case NODE_REMOVED:
+                case NODE_COMPLETE:
+                case NODE_INCOMPLETE:
+                default:
+                    // do nothing
+                    break;
+            }
+        }
+    }
+
+    private void readControllers() {
+        CordVtnConfig config = configService.getConfig(appId, CordVtnConfig.class);
+        if (config == null) {
+            log.warn("No configuration found");
+            return;
+        }
+        controllers = config.controllers();
+        controllers.forEach(ctrl -> {
+            log.debug("Added controller {}:{}", ctrl.ip(), ctrl.port());
+        });
+    }
+
+    private class InternalConfigListener implements NetworkConfigListener {
+
+        @Override
+        public void event(NetworkConfigEvent event) {
+            if (!event.configClass().equals(CordVtnConfig.class)) {
+                return;
+            }
+
+            switch (event.type()) {
+                case CONFIG_ADDED:
+                case CONFIG_UPDATED:
+                    readControllers();
+                    break;
+                default:
+                    break;
+            }
+        }
+    }
+}
diff --git a/src/main/java/org/opencord/cordvtn/impl/CordVtnPipeline.java b/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnPipeline.java
similarity index 81%
rename from src/main/java/org/opencord/cordvtn/impl/CordVtnPipeline.java
rename to src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnPipeline.java
index af6f27c..812f99c 100644
--- a/src/main/java/org/opencord/cordvtn/impl/CordVtnPipeline.java
+++ b/src/main/java/org/opencord/cordvtn/impl/DefaultCordVtnPipeline.java
@@ -30,13 +30,12 @@
 import org.onosproject.net.AnnotationKeys;
 import org.onosproject.net.Port;
 import org.opencord.cordvtn.api.Constants;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
 import org.opencord.cordvtn.api.node.CordVtnNode;
 import org.onosproject.core.ApplicationId;
 import org.onosproject.core.CoreService;
-import org.onosproject.net.Device;
 import org.onosproject.net.DeviceId;
 import org.onosproject.net.PortNumber;
-import org.onosproject.net.behaviour.ExtensionTreatmentResolver;
 import org.onosproject.net.device.DeviceService;
 import org.onosproject.net.flow.DefaultFlowRule;
 import org.onosproject.net.flow.DefaultTrafficSelector;
@@ -47,23 +46,20 @@
 import org.onosproject.net.flow.FlowRuleService;
 import org.onosproject.net.flow.TrafficSelector;
 import org.onosproject.net.flow.TrafficTreatment;
-import org.onosproject.net.flow.instructions.ExtensionPropertyException;
-import org.onosproject.net.flow.instructions.ExtensionTreatment;
 import org.slf4j.Logger;
 
-import java.util.Optional;
 
-import static com.google.common.base.Preconditions.checkNotNull;
-import static org.onosproject.net.flow.instructions.ExtensionTreatmentType.ExtensionTreatmentTypes.NICIRA_SET_TUNNEL_DST;
+import static com.google.common.base.Preconditions.checkArgument;
 import static org.opencord.cordvtn.api.Constants.DEFAULT_TUNNEL;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.COMPLETE;
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
- * Provides CORD VTN pipeline.
+ * Implementation of cordvtn pipeline.
  */
 @Component(immediate = true)
-@Service(value = CordVtnPipeline.class)
-public final class CordVtnPipeline {
+@Service
+public class DefaultCordVtnPipeline implements CordVtnPipeline {
 
     protected final Logger log = getLogger(getClass());
 
@@ -76,26 +72,7 @@
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected DeviceService deviceService;
 
-    // tables
-    public static final int TABLE_ZERO = 0;
-    public static final int TABLE_IN_PORT = 1;
-    public static final int TABLE_ACCESS = 2;
-    public static final int TABLE_IN_SERVICE = 3;
-    public static final int TABLE_DST = 4;
-    public static final int TABLE_TUNNEL_IN = 5;
-    public static final int TABLE_VLAN = 6;
-
-    // priorities
-    public static final int PRIORITY_MANAGEMENT = 55000;
-    public static final int PRIORITY_HIGH = 50000;
-    public static final int PRIORITY_DEFAULT = 5000;
-    public static final int PRIORITY_LOW = 4000;
-    public static final int PRIORITY_ZERO = 0;
-
-    public static final int VXLAN_UDP_PORT = 4789;
-    public static final VlanId VLAN_WAN = VlanId.vlanId((short) 500);
-
-    public static final String PROPERTY_TUNNEL_DST = "tunnelDst";
+    private static final int VXLAN_UDP_PORT = 4789;
 
     private ApplicationId appId;
 
@@ -110,45 +87,45 @@
         log.info("Stopped");
     }
 
-    /**
-     * Flush flows installed by this application.
-     */
-    public void flushRules() {
+    @Override
+    public void cleanupPipeline() {
         flowRuleService.getFlowRulesById(appId).forEach(flowRule -> processFlowRule(false, flowRule));
     }
 
-    /**
-     * Installs table miss rule to a give device.
-     *
-     * @param node cordvtn node
-     */
+    @Override
     public void initPipeline(CordVtnNode node) {
-        checkNotNull(node);
+        checkArgument(node.state() == COMPLETE, "Node is not in COMPLETE state");
 
-        Optional<PortNumber> dataPort = getPortNumber(node.integrationBridgeId(), node.dataIface());
-        Optional<PortNumber> tunnelPort = getPortNumber(node.integrationBridgeId(), DEFAULT_TUNNEL);
-        if (!dataPort.isPresent() || !tunnelPort.isPresent()) {
-            log.warn("Node is not in COMPLETE state");
-            return;
-        }
-
-        Optional<PortNumber> hostMgmtPort = Optional.empty();
-        if (node.hostMgmtIface().isPresent()) {
-            hostMgmtPort = getPortNumber(node.integrationBridgeId(), node.hostMgmtIface().get());
-        }
+        PortNumber dataPort = getPortNumber(node.integrationBridgeId(), node.dataInterface());
+        PortNumber tunnelPort = getPortNumber(node.integrationBridgeId(), DEFAULT_TUNNEL);
+        PortNumber hostMgmtPort = node.hostManagementInterface() == null ?
+                null : getPortNumber(node.integrationBridgeId(), node.hostManagementInterface());
 
         processTableZero(node.integrationBridgeId(),
-                         dataPort.get(),
-                         node.dataIp().ip(),
-                         node.localMgmtIp().ip());
+                dataPort,
+                node.dataIp().ip(),
+                node.localManagementIp().ip());
 
         processInPortTable(node.integrationBridgeId(),
-                           tunnelPort.get(),
-                           dataPort.get(),
-                           hostMgmtPort);
+                tunnelPort,
+                dataPort,
+                hostMgmtPort);
 
-        processAccessTypeTable(node.integrationBridgeId(), dataPort.get());
-        processVlanTable(node.integrationBridgeId(), dataPort.get());
+        processAccessTypeTable(node.integrationBridgeId(), dataPort);
+        processVlanTable(node.integrationBridgeId(), dataPort);
+    }
+
+    @Override
+    public void processFlowRule(boolean install, FlowRule rule) {
+        FlowRuleOperations.Builder oBuilder = FlowRuleOperations.builder();
+        oBuilder = install ? oBuilder.add(rule) : oBuilder.remove(rule);
+
+        flowRuleService.apply(oBuilder.build(new FlowRuleOperationsContext() {
+            @Override
+            public void onError(FlowRuleOperations ops) {
+                log.error(String.format("Failed %s, %s", ops.toString(), rule.toString()));
+            }
+        }));
     }
 
     private void processTableZero(DeviceId deviceId, PortNumber dataPort, IpAddress dataIp,
@@ -380,7 +357,7 @@
     }
 
     private void processInPortTable(DeviceId deviceId, PortNumber tunnelPort, PortNumber dataPort,
-                                    Optional<PortNumber> hostMgmtPort) {
+                                    PortNumber hostMgmtPort) {
         TrafficSelector selector = DefaultTrafficSelector.builder()
                 .matchInPort(tunnelPort)
                 .build();
@@ -421,9 +398,9 @@
 
         processFlowRule(true, flowRule);
 
-        if (hostMgmtPort.isPresent()) {
+        if (hostMgmtPort != null) {
             selector = DefaultTrafficSelector.builder()
-                    .matchInPort(hostMgmtPort.get())
+                    .matchInPort(hostMgmtPort)
                     .build();
 
             treatment = DefaultTrafficTreatment.builder()
@@ -510,43 +487,11 @@
         processFlowRule(true, flowRule);
     }
 
-    public void processFlowRule(boolean install, FlowRule rule) {
-        FlowRuleOperations.Builder oBuilder = FlowRuleOperations.builder();
-        oBuilder = install ? oBuilder.add(rule) : oBuilder.remove(rule);
-
-        flowRuleService.apply(oBuilder.build(new FlowRuleOperationsContext() {
-            @Override
-            public void onError(FlowRuleOperations ops) {
-                log.error(String.format("Failed %s, %s", ops.toString(), rule.toString()));
-            }
-        }));
-    }
-
-    public ExtensionTreatment tunnelDstTreatment(DeviceId deviceId, Ip4Address remoteIp) {
-        Device device = deviceService.getDevice(deviceId);
-        if (device != null && !device.is(ExtensionTreatmentResolver.class)) {
-            log.error("The extension treatment is not supported");
-            return null;
-        }
-
-        ExtensionTreatmentResolver resolver = device.as(ExtensionTreatmentResolver.class);
-        ExtensionTreatment treatment = resolver.getExtensionInstruction(NICIRA_SET_TUNNEL_DST.type());
-        try {
-            treatment.setPropertyValue(PROPERTY_TUNNEL_DST, remoteIp);
-            return treatment;
-        } catch (ExtensionPropertyException e) {
-            log.warn("Failed to get tunnelDst extension treatment for {}", deviceId);
-            return null;
-        }
-    }
-
-    private Optional<PortNumber> getPortNumber(DeviceId deviceId, String portName) {
-        PortNumber port = deviceService.getPorts(deviceId).stream()
+    private PortNumber getPortNumber(DeviceId deviceId, String portName) {
+        return deviceService.getPorts(deviceId).stream()
                 .filter(p -> p.annotations().value(AnnotationKeys.PORT_NAME).equals(portName) &&
                         p.isEnabled())
                 .map(Port::number)
-                .findAny()
-                .orElse(null);
-        return Optional.ofNullable(port);
+                .findAny().orElse(null);
     }
 }
diff --git a/src/main/java/org/opencord/cordvtn/impl/DistributedCordVtnNodeStore.java b/src/main/java/org/opencord/cordvtn/impl/DistributedCordVtnNodeStore.java
new file mode 100644
index 0000000..6bd3875
--- /dev/null
+++ b/src/main/java/org/opencord/cordvtn/impl/DistributedCordVtnNodeStore.java
@@ -0,0 +1,207 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import com.google.common.collect.ImmutableSet;
+import org.apache.felix.scr.annotations.Activate;
+import org.apache.felix.scr.annotations.Component;
+import org.apache.felix.scr.annotations.Deactivate;
+import org.apache.felix.scr.annotations.Reference;
+import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.apache.felix.scr.annotations.Service;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.store.AbstractStore;
+import org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.ConsistentMap;
+import org.onosproject.store.service.MapEvent;
+import org.onosproject.store.service.MapEventListener;
+import org.onosproject.store.service.Serializer;
+import org.onosproject.store.service.StorageService;
+import org.onosproject.store.service.Versioned;
+import org.opencord.cordvtn.api.net.CidrAddr;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeEvent;
+import org.opencord.cordvtn.api.node.CordVtnNodeHandler;
+import org.opencord.cordvtn.api.node.CordVtnNodeState;
+import org.opencord.cordvtn.api.node.CordVtnNodeStore;
+import org.opencord.cordvtn.api.node.CordVtnNodeStoreDelegate;
+import org.opencord.cordvtn.api.node.SshAccessInfo;
+import org.slf4j.Logger;
+
+import java.util.Set;
+import java.util.concurrent.ExecutorService;
+import java.util.stream.Collectors;
+
+import static com.google.common.base.Preconditions.checkArgument;
+import static java.util.concurrent.Executors.newSingleThreadExecutor;
+import static org.onlab.util.Tools.groupedThreads;
+import static org.opencord.cordvtn.api.Constants.CORDVTN_APP_ID;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.COMPLETE;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Manages the inventory of cordvtn nodes using a {@link ConsistentMap}.
+ */
+@Component(immediate = true)
+@Service
+public class DistributedCordVtnNodeStore extends AbstractStore<CordVtnNodeEvent, CordVtnNodeStoreDelegate>
+    implements CordVtnNodeStore {
+
+    protected final Logger log = getLogger(getClass());
+
+    private static final String ERR_NOT_FOUND = " does not exist";
+    private static final String ERR_DUPLICATE = " already exists";
+
+    private static final KryoNamespace SERIALIZER_CORDVTN_NODE = KryoNamespace.newBuilder()
+            .register(KryoNamespaces.API)
+            .register(CordVtnNode.class)
+            .register(DefaultCordVtnNode.class)
+            .register(CidrAddr.class)
+            .register(SshAccessInfo.class)
+            .register(CordVtnNodeState.class)
+            .register(CordVtnNodeHandler.class)
+            .register(DefaultCordVtnNodeHandler.class)
+            .build();
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CoreService coreService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected StorageService storageService;
+
+    private final ExecutorService eventExecutor = newSingleThreadExecutor(
+            groupedThreads(this.getClass().getSimpleName(), "event-handler", log));
+    private final MapEventListener<String, CordVtnNode> nodeStoreListener = new InternalMapListener();
+    private ConsistentMap<String, CordVtnNode> nodeStore;
+
+    @Activate
+    protected void activate() {
+        ApplicationId appId = coreService.registerApplication(CORDVTN_APP_ID);
+        nodeStore = storageService.<String, CordVtnNode>consistentMapBuilder()
+                .withSerializer(Serializer.using(SERIALIZER_CORDVTN_NODE))
+                .withName("cordvtn-nodestore")
+                .withApplicationId(appId)
+                .build();
+        nodeStore.addListener(nodeStoreListener);
+        log.info("Started");
+    }
+
+    @Deactivate
+    protected void deactivate() {
+        nodeStore.removeListener(nodeStoreListener);
+        log.info("Stopped");
+    }
+
+    @Override
+    public Set<CordVtnNode> nodes() {
+        Set<CordVtnNode> nodes = nodeStore.values().stream()
+                .map(Versioned::value)
+                .collect(Collectors.toSet());
+        return ImmutableSet.copyOf(nodes);
+    }
+
+    @Override
+    public CordVtnNode node(String hostname) {
+        Versioned<CordVtnNode> versioned = nodeStore.get(hostname);
+        return versioned == null ? null : versioned.value();
+    }
+
+    @Override
+    public void createNode(CordVtnNode node) {
+        nodeStore.compute(node.hostname(), (hostname, existing) -> {
+            final String error = node.hostname() + ERR_DUPLICATE;
+            checkArgument(existing == null, error);
+            return node;
+        });
+    }
+
+    @Override
+    public void updateNode(CordVtnNode node) {
+        nodeStore.compute(node.hostname(), (hostname, existing) -> {
+            final String error = node.hostname() + ERR_NOT_FOUND;
+            checkArgument(existing != null, error);
+            return node;
+        });
+    }
+
+    @Override
+    public CordVtnNode removeNode(String hostname) {
+        Versioned<CordVtnNode> removed = nodeStore.remove(hostname);
+        return removed == null ? null : removed.value();
+    }
+
+    private class InternalMapListener implements MapEventListener<String, CordVtnNode> {
+
+        @Override
+        public void event(MapEvent<String, CordVtnNode> event) {
+            switch (event.type()) {
+                case INSERT:
+                    log.debug("CordVtn node is created {}", event.newValue().value());
+                    eventExecutor.execute(() -> {
+                        notifyDelegate(new CordVtnNodeEvent(
+                                CordVtnNodeEvent.Type.NODE_CREATED,
+                                event.newValue().value()
+                        ));
+                        if (event.newValue().value().state() == COMPLETE) {
+                            notifyDelegate(new CordVtnNodeEvent(
+                                    CordVtnNodeEvent.Type.NODE_COMPLETE,
+                                    event.newValue().value()
+                            ));
+                        }
+                    });
+                    break;
+                case UPDATE:
+                    log.debug("CordVtn node is updated {}", event.newValue().value());
+                    eventExecutor.execute(() -> {
+                        notifyDelegate(new CordVtnNodeEvent(
+                                CordVtnNodeEvent.Type.NODE_UPDATED,
+                                event.newValue().value()
+                        ));
+                        processUpdated(event.oldValue().value(), event.newValue().value());
+                    });
+                    break;
+                case REMOVE:
+                    log.debug("CordVtn node is removed {}", event.oldValue().value());
+                    eventExecutor.execute(() -> {
+                        notifyDelegate(new CordVtnNodeEvent(
+                                CordVtnNodeEvent.Type.NODE_REMOVED,
+                                event.oldValue().value()
+                        ));
+                    });
+                    break;
+                default:
+                    // do nothing
+                    break;
+            }
+        }
+
+        private void processUpdated(CordVtnNode oldNode, CordVtnNode newNode) {
+            if (oldNode.state() != COMPLETE && newNode.state() == COMPLETE) {
+                notifyDelegate(new CordVtnNodeEvent(
+                        CordVtnNodeEvent.Type.NODE_COMPLETE,
+                        newNode
+                ));
+            } else if (oldNode.state() == COMPLETE && newNode.state() != COMPLETE) {
+                notifyDelegate(new CordVtnNodeEvent(
+                        CordVtnNodeEvent.Type.NODE_INCOMPLETE,
+                        newNode
+                ));
+            }
+        }
+    }
+}
diff --git a/src/main/java/org/opencord/cordvtn/impl/DistributedServiceNetworkStore.java b/src/main/java/org/opencord/cordvtn/impl/DistributedServiceNetworkStore.java
index dc98ced..212a90e 100644
--- a/src/main/java/org/opencord/cordvtn/impl/DistributedServiceNetworkStore.java
+++ b/src/main/java/org/opencord/cordvtn/impl/DistributedServiceNetworkStore.java
@@ -95,7 +95,7 @@
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected StorageService storageService;
 
-   private final ExecutorService eventExecutor = newSingleThreadExecutor(
+    private final ExecutorService eventExecutor = newSingleThreadExecutor(
             groupedThreads(this.getClass().getSimpleName(), "event-handler", log));
     private final MapEventListener<PortId, ServicePort> servicePortListener =
             new ServicePortMapListener();
@@ -108,7 +108,6 @@
     @Activate
     protected void activate() {
         ApplicationId appId = coreService.registerApplication(CORDVTN_APP_ID);
-
         serviceNetworkStore = storageService.<NetworkId, ServiceNetwork>consistentMapBuilder()
                 .withSerializer(Serializer.using(SERIALIZER_SERVICE))
                 .withName("cordvtn-servicenetstore")
diff --git a/src/main/java/org/opencord/cordvtn/impl/InstanceManager.java b/src/main/java/org/opencord/cordvtn/impl/InstanceManager.java
index e8983c6..bd5e528 100644
--- a/src/main/java/org/opencord/cordvtn/impl/InstanceManager.java
+++ b/src/main/java/org/opencord/cordvtn/impl/InstanceManager.java
@@ -268,23 +268,26 @@
 
         @Override
         public void event(ServiceNetworkEvent event) {
-            NodeId leader = leadershipService.getLeader(appId.name());
-            if (!Objects.equals(localNodeId, leader)) {
-                // do not allow to proceed without leadership
-                return;
-            }
+            eventExecutor.execute(() -> {
+                NodeId leader = leadershipService.getLeader(appId.name());
+                if (!Objects.equals(localNodeId, leader)) {
+                    // do not allow to proceed without leadership
+                    return;
+                }
+                handle(event);
+            });
+        }
 
+        private void handle(ServiceNetworkEvent event) {
             switch (event.type()) {
                 case SERVICE_PORT_CREATED:
                 case SERVICE_PORT_UPDATED:
                     log.debug("Processing service port {}", event.servicePort());
                     PortId portId = event.servicePort().id();
-                    eventExecutor.execute(() -> {
-                        Instance instance = getInstance(portId);
-                        if (instance != null) {
-                            addInstance(instance.host().location());
-                        }
-                    });
+                    Instance instance = getInstance(portId);
+                    if (instance != null) {
+                        addInstance(instance.host().location());
+                    }
                     break;
                 case SERVICE_PORT_REMOVED:
                 case SERVICE_NETWORK_CREATED:
diff --git a/src/main/java/org/opencord/cordvtn/impl/handler/AbstractInstanceHandler.java b/src/main/java/org/opencord/cordvtn/impl/handler/AbstractInstanceHandler.java
index 64cda2e..59cb7f7 100644
--- a/src/main/java/org/opencord/cordvtn/impl/handler/AbstractInstanceHandler.java
+++ b/src/main/java/org/opencord/cordvtn/impl/handler/AbstractInstanceHandler.java
@@ -18,11 +18,21 @@
 import com.google.common.collect.ImmutableSet;
 import org.onlab.osgi.DefaultServiceDirectory;
 import org.onlab.osgi.ServiceDirectory;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.IpAddress;
 import org.onlab.util.Tools;
 import org.onosproject.core.ApplicationId;
 import org.onosproject.core.CoreService;
 import org.onosproject.mastership.MastershipService;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
 import org.onosproject.net.Host;
+import org.onosproject.net.Port;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.behaviour.ExtensionTreatmentResolver;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.flow.instructions.ExtensionPropertyException;
+import org.onosproject.net.flow.instructions.ExtensionTreatment;
 import org.onosproject.net.host.HostEvent;
 import org.onosproject.net.host.HostListener;
 import org.onosproject.net.host.HostService;
@@ -33,15 +43,21 @@
 import org.opencord.cordvtn.api.net.NetworkId;
 import org.opencord.cordvtn.api.net.ServiceNetwork;
 import org.opencord.cordvtn.api.net.ServicePort;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 import org.slf4j.Logger;
 
 import java.util.Objects;
+import java.util.Optional;
 import java.util.Set;
 import java.util.concurrent.ExecutorService;
 import java.util.stream.Collectors;
 
 import static java.util.concurrent.Executors.newSingleThreadExecutor;
 import static org.onlab.util.Tools.groupedThreads;
+import static org.onosproject.net.AnnotationKeys.PORT_NAME;
+import static org.onosproject.net.flow.instructions.ExtensionTreatmentType.ExtensionTreatmentTypes.NICIRA_SET_TUNNEL_DST;
+import static org.opencord.cordvtn.api.Constants.DEFAULT_TUNNEL;
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
@@ -53,11 +69,14 @@
 
     protected static final String ERR_VTN_NETWORK = "Failed to get VTN network for %s";
     protected static final String ERR_VTN_PORT = "Failed to get VTN port for %s";
+    protected static final String PROPERTY_TUNNEL_DST = "tunnelDst";
 
     protected CoreService coreService;
     protected MastershipService mastershipService;
     protected HostService hostService;
+    protected DeviceService deviceService;
     protected ServiceNetworkService snetService;
+    protected CordVtnNodeService nodeService;
     protected ApplicationId appId;
     protected Set<ServiceNetwork.NetworkType> netTypes = ImmutableSet.of();
 
@@ -71,7 +90,9 @@
         coreService = services.get(CoreService.class);
         mastershipService = services.get(MastershipService.class);
         hostService = services.get(HostService.class);
+        deviceService = services.get(DeviceService.class);
         snetService = services.get(ServiceNetworkService.class);
+        nodeService = services.get(CordVtnNodeService.class);
 
         appId = coreService.registerApplication(Constants.CORDVTN_APP_ID);
         hostService.addListener(hostListener);
@@ -118,6 +139,75 @@
         return sport;
     }
 
+    protected PortNumber dataPort(DeviceId deviceId) {
+        CordVtnNode node = nodeService.node(deviceId);
+        if (node == null) {
+            log.debug("Failed to get node for {}", deviceId);
+            return null;
+        }
+        Optional<PortNumber> port = getPortNumber(deviceId, node.dataInterface());
+        return port.isPresent() ? port.get() : null;
+
+    }
+
+    protected PortNumber tunnelPort(DeviceId deviceId) {
+        Optional<PortNumber> port = getPortNumber(deviceId, DEFAULT_TUNNEL);
+        return port.isPresent() ? port.get() : null;
+    }
+
+    protected PortNumber hostManagementPort(DeviceId deviceId) {
+        CordVtnNode node = nodeService.node(deviceId);
+        if (node == null) {
+            log.debug("Failed to get node for {}", deviceId);
+            return null;
+        }
+
+        if (node.hostManagementInterface() != null) {
+            Optional<PortNumber> port =
+                    getPortNumber(deviceId, node.hostManagementInterface());
+            return port.isPresent() ? port.get() : null;
+        } else {
+            return null;
+        }
+    }
+
+    protected ExtensionTreatment tunnelDstTreatment(DeviceId deviceId, Ip4Address remoteIp) {
+        Device device = deviceService.getDevice(deviceId);
+        if (device != null && !device.is(ExtensionTreatmentResolver.class)) {
+            log.error("The extension treatment is not supported");
+            return null;
+        }
+
+        ExtensionTreatmentResolver resolver = device.as(ExtensionTreatmentResolver.class);
+        ExtensionTreatment treatment = resolver.getExtensionInstruction(NICIRA_SET_TUNNEL_DST.type());
+        try {
+            treatment.setPropertyValue(PROPERTY_TUNNEL_DST, remoteIp);
+            return treatment;
+        } catch (ExtensionPropertyException e) {
+            log.warn("Failed to get tunnelDst extension treatment for {}", deviceId);
+            return null;
+        }
+    }
+
+    protected IpAddress dataIp(DeviceId deviceId) {
+        CordVtnNode node = nodeService.node(deviceId);
+        if (node == null) {
+            log.debug("Failed to get node for {}", deviceId);
+            return null;
+        }
+        return node.dataIp().ip();
+    }
+
+    private Optional<PortNumber> getPortNumber(DeviceId deviceId, String portName) {
+        PortNumber port = deviceService.getPorts(deviceId).stream()
+                .filter(p -> p.annotations().value(PORT_NAME).equals(portName) &&
+                        p.isEnabled())
+                .map(Port::number)
+                .findAny()
+                .orElse(null);
+        return Optional.ofNullable(port);
+    }
+
     private class InternalHostListener implements HostListener {
 
         @Override
diff --git a/src/main/java/org/opencord/cordvtn/impl/handler/AccessAgentInstanceHandler.java b/src/main/java/org/opencord/cordvtn/impl/handler/AccessAgentInstanceHandler.java
index 460ba25..82de7fc 100644
--- a/src/main/java/org/opencord/cordvtn/impl/handler/AccessAgentInstanceHandler.java
+++ b/src/main/java/org/opencord/cordvtn/impl/handler/AccessAgentInstanceHandler.java
@@ -28,10 +28,11 @@
 import org.onosproject.net.flow.FlowRule;
 import org.onosproject.net.flow.TrafficSelector;
 import org.onosproject.net.flow.TrafficTreatment;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
 import org.opencord.cordvtn.api.core.Instance;
 import org.opencord.cordvtn.api.core.InstanceHandler;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
-import org.opencord.cordvtn.impl.CordVtnPipeline;
+import org.opencord.cordvtn.api.core.ServiceNetworkService;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 
 import static org.opencord.cordvtn.api.net.ServiceNetwork.NetworkType.ACCESS_AGENT;
 
@@ -42,10 +43,13 @@
 public class AccessAgentInstanceHandler extends AbstractInstanceHandler implements InstanceHandler {
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnPipeline pipeline;
+    protected ServiceNetworkService snetService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnNodeManager nodeManager;
+    protected CordVtnNodeService nodeService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnPipeline pipeline;
 
     @Activate
     protected void activate() {
@@ -96,7 +100,7 @@
                 .build();
 
         treatment = DefaultTrafficTreatment.builder()
-                .setOutput(nodeManager.dataPort(instance.deviceId()))
+                .setOutput(dataPort(instance.deviceId()))
                 .build();
 
         flowRule = DefaultFlowRule.builder()
diff --git a/src/main/java/org/opencord/cordvtn/impl/handler/DefaultInstanceHandler.java b/src/main/java/org/opencord/cordvtn/impl/handler/DefaultInstanceHandler.java
index 3f68c22..8279d34 100644
--- a/src/main/java/org/opencord/cordvtn/impl/handler/DefaultInstanceHandler.java
+++ b/src/main/java/org/opencord/cordvtn/impl/handler/DefaultInstanceHandler.java
@@ -47,15 +47,16 @@
 import org.onosproject.net.flow.instructions.L2ModificationInstruction;
 import org.onosproject.net.host.DefaultHostDescription;
 import org.onosproject.net.host.HostDescription;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
 import org.opencord.cordvtn.api.core.Instance;
 import org.opencord.cordvtn.api.core.InstanceHandler;
 import org.opencord.cordvtn.api.core.InstanceService;
+import org.opencord.cordvtn.api.core.ServiceNetworkService;
 import org.opencord.cordvtn.api.net.AddressPair;
 import org.opencord.cordvtn.api.net.ServiceNetwork;
 import org.opencord.cordvtn.api.net.ServicePort;
 import org.opencord.cordvtn.api.node.CordVtnNode;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
-import org.opencord.cordvtn.impl.CordVtnPipeline;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 
 import java.util.Set;
 import java.util.stream.Collectors;
@@ -74,10 +75,13 @@
     protected FlowRuleService flowRuleService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnPipeline pipeline;
+    protected ServiceNetworkService snetService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnNodeManager nodeManager;
+    protected CordVtnNodeService nodeService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnPipeline pipeline;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected InstanceService instanceService;
@@ -95,10 +99,10 @@
 
     @Override
     public void instanceDetected(Instance instance) {
+        log.info("Instance is detected or updated {}", instance);
         if (instance.isAdditionalInstance()) {
             return;
         }
-        log.info("Instance is detected or updated {}", instance);
 
         ServiceNetwork snet = getServiceNetwork(instance);
         populateDefaultRules(instance, snet, true);
@@ -109,7 +113,7 @@
             populateVlanRule(
                     instance,
                     sport.vlanId(),
-                    nodeManager.dataPort(instance.deviceId()),
+                    dataPort(instance.deviceId()),
                     true);
         }
         // FIXME don't add the existing instance again
@@ -138,7 +142,7 @@
             populateVlanRule(
                     instance,
                     sport.vlanId(),
-                    nodeManager.dataPort(instance.deviceId()),
+                    dataPort(instance.deviceId()),
                     false);
         }
         boolean isOriginalInstance = !instance.isAdditionalInstance();
@@ -246,7 +250,7 @@
     }
 
     private void populateDstIpRule(Instance instance, long vni, boolean install) {
-        Ip4Address tunnelIp = nodeManager.dataIp(instance.deviceId()).getIp4Address();
+        Ip4Address tunnelIp = dataIp(instance.deviceId()).getIp4Address();
 
         TrafficSelector selector = DefaultTrafficSelector.builder()
                 .matchEthType(Ethernet.TYPE_IPV4)
@@ -270,13 +274,13 @@
 
         pipeline.processFlowRule(install, flowRule);
 
-        for (CordVtnNode node : nodeManager.completeNodes()) {
+        for (CordVtnNode node : nodeService.completeNodes()) {
             if (node.integrationBridgeId().equals(instance.deviceId())) {
                 continue;
             }
 
             ExtensionTreatment tunnelDst =
-                    pipeline.tunnelDstTreatment(node.integrationBridgeId(), tunnelIp);
+                    tunnelDstTreatment(node.integrationBridgeId(), tunnelIp);
             if (tunnelDst == null) {
                 continue;
             }
@@ -285,7 +289,7 @@
                     .setEthDst(instance.mac())
                     .setTunnelId(vni)
                     .extension(tunnelDst, node.integrationBridgeId())
-                    .setOutput(nodeManager.tunnelPort(node.integrationBridgeId()))
+                    .setOutput(tunnelPort(node.integrationBridgeId()))
                     .build();
 
             flowRule = DefaultFlowRule.builder()
@@ -337,7 +341,7 @@
                 .build();
 
 
-        nodeManager.completeNodes().forEach(node -> {
+        nodeService.completeNodes().forEach(node -> {
             FlowRule flowRuleDirect = DefaultFlowRule.builder()
                     .fromApp(appId)
                     .withSelector(selector)
@@ -362,7 +366,7 @@
                 .drop()
                 .build();
 
-        nodeManager.completeNodes().forEach(node -> {
+        nodeService.completeNodes().forEach(node -> {
             FlowRule flowRuleDirect = DefaultFlowRule.builder()
                     .fromApp(appId)
                     .withSelector(selector)
diff --git a/src/main/java/org/opencord/cordvtn/impl/handler/DependencyHandler.java b/src/main/java/org/opencord/cordvtn/impl/handler/DependencyHandler.java
index 772e1bc..ba63cdd 100644
--- a/src/main/java/org/opencord/cordvtn/impl/handler/DependencyHandler.java
+++ b/src/main/java/org/opencord/cordvtn/impl/handler/DependencyHandler.java
@@ -50,16 +50,16 @@
 import org.onosproject.net.group.GroupDescription;
 import org.onosproject.net.group.GroupKey;
 import org.onosproject.net.group.GroupService;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
 import org.opencord.cordvtn.api.core.Instance;
-import org.opencord.cordvtn.api.core.ServiceNetworkAdminService;
 import org.opencord.cordvtn.api.core.ServiceNetworkEvent;
 import org.opencord.cordvtn.api.core.ServiceNetworkListener;
+import org.opencord.cordvtn.api.core.ServiceNetworkService;
 import org.opencord.cordvtn.api.net.NetworkId;
 import org.opencord.cordvtn.api.net.ServiceNetwork;
 import org.opencord.cordvtn.api.net.ServiceNetwork.DependencyType;
 import org.opencord.cordvtn.api.node.CordVtnNode;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
-import org.opencord.cordvtn.impl.CordVtnPipeline;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 import org.slf4j.Logger;
 
 import java.util.List;
@@ -69,9 +69,9 @@
 import java.util.stream.Collectors;
 
 import static org.onosproject.net.group.DefaultGroupBucket.createSelectGroupBucket;
+import static org.opencord.cordvtn.api.core.CordVtnPipeline.*;
 import static org.opencord.cordvtn.api.net.ServiceNetwork.DependencyType.BIDIRECTIONAL;
 import static org.opencord.cordvtn.api.net.ServiceNetwork.NetworkType.*;
-import static org.opencord.cordvtn.impl.CordVtnPipeline.*;
 import static org.slf4j.LoggerFactory.getLogger;
 
 /**
@@ -97,14 +97,14 @@
     protected ClusterService clusterService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ServiceNetworkService snetService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnNodeService nodeService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected CordVtnPipeline pipeline;
 
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnNodeManager nodeManager;
-
-    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected ServiceNetworkAdminService snetService;
-
     private final ServiceNetworkListener snetListener = new InternalServiceNetworkListener();
     private NodeId localNodeId;
 
@@ -172,7 +172,7 @@
     }
 
     private void updateProviderInstances(ServiceNetwork provider) {
-        Set<DeviceId> devices = nodeManager.completeNodes().stream()
+        Set<DeviceId> devices = nodeService.completeNodes().stream()
                 .map(CordVtnNode::integrationBridgeId)
                 .collect(Collectors.toSet());
 
@@ -239,7 +239,7 @@
 
     private void removeGroup(NetworkId netId) {
         GroupKey groupKey = getGroupKey(netId);
-        nodeManager.completeNodes().forEach(node -> {
+        nodeService.completeNodes().forEach(node -> {
             DeviceId deviceId = node.integrationBridgeId();
             Group group = groupService.getGroup(deviceId, groupKey);
             if (group != null) {
@@ -285,7 +285,7 @@
         Map<DeviceId, GroupId> providerGroups = Maps.newHashMap();
         Map<DeviceId, Set<PortNumber>> subscriberPorts = Maps.newHashMap();
 
-        nodeManager.completeNodes().forEach(node -> {
+        nodeService.completeNodes().forEach(node -> {
             DeviceId deviceId = node.integrationBridgeId();
             GroupId groupId = getProviderGroup(provider, deviceId);
             providerGroups.put(deviceId, groupId);
@@ -355,7 +355,7 @@
                 .transition(TABLE_DST)
                 .build();
 
-        nodeManager.completeNodes().forEach(node -> {
+        nodeService.completeNodes().forEach(node -> {
             DeviceId deviceId = node.integrationBridgeId();
             FlowRule flowRuleDirect = DefaultFlowRule.builder()
                     .fromApp(appId)
@@ -409,7 +409,7 @@
                                                  Set<Instance> instances) {
         List<GroupBucket> buckets = Lists.newArrayList();
         instances.forEach(instance -> {
-            Ip4Address tunnelIp = nodeManager.dataIp(instance.deviceId()).getIp4Address();
+            Ip4Address tunnelIp = dataIp(instance.deviceId()).getIp4Address();
 
             if (deviceId.equals(instance.deviceId())) {
                 TrafficTreatment treatment = DefaultTrafficTreatment.builder()
@@ -418,13 +418,12 @@
                         .build();
                 buckets.add(createSelectGroupBucket(treatment));
             } else {
-                ExtensionTreatment tunnelDst =
-                        pipeline.tunnelDstTreatment(deviceId, tunnelIp);
+                ExtensionTreatment tunnelDst = tunnelDstTreatment(deviceId, tunnelIp);
                 TrafficTreatment treatment = DefaultTrafficTreatment.builder()
                         .setEthDst(instance.mac())
                         .extension(tunnelDst, deviceId)
                         .setTunnelId(tunnelId)
-                        .setOutput(nodeManager.tunnelPort(instance.deviceId()))
+                        .setOutput(tunnelPort(instance.deviceId()))
                         .build();
                 buckets.add(createSelectGroupBucket(treatment));
             }
@@ -435,33 +434,30 @@
     private class InternalServiceNetworkListener implements ServiceNetworkListener {
 
         @Override
-        public boolean isRelevant(ServiceNetworkEvent event) {
-            // do not allow to proceed without leadership
-            NodeId leader = leadershipService.getLeader(appId.name());
-            return Objects.equals(localNodeId, leader);
+        public void event(ServiceNetworkEvent event) {
+            eventExecutor.execute(() -> {
+                NodeId leader = leadershipService.getLeader(appId.name());
+                if (!Objects.equals(localNodeId, leader)) {
+                    // do not allow to proceed without leadership
+                    return;
+                }
+                handle(event);
+            });
         }
 
-        @Override
-        public void event(ServiceNetworkEvent event) {
-
+        private void handle(ServiceNetworkEvent event) {
             switch (event.type()) {
                 case SERVICE_NETWORK_PROVIDER_ADDED:
                     log.debug("Dependency added: {}", event);
-                    eventExecutor.execute(() -> {
-                        dependencyAdded(
-                                event.subject(),
-                                event.provider().provider(),
-                                event.provider().type());
-                    });
+                    dependencyAdded(event.subject(),
+                            event.provider().provider(),
+                            event.provider().type());
                     break;
                 case SERVICE_NETWORK_PROVIDER_REMOVED:
                     log.debug("Dependency removed: {}", event);
-                    eventExecutor.execute(() -> {
-                        dependencyRemoved(
-                                event.subject(),
-                                event.provider().provider(),
-                                event.provider().type());
-                    });
+                    dependencyRemoved(event.subject(),
+                            event.provider().provider(),
+                            event.provider().type());
                     break;
                 case SERVICE_NETWORK_CREATED:
                 case SERVICE_NETWORK_UPDATED:
diff --git a/src/main/java/org/opencord/cordvtn/impl/handler/ManagementInstanceHandler.java b/src/main/java/org/opencord/cordvtn/impl/handler/ManagementInstanceHandler.java
index 0475f07..aea5da2 100644
--- a/src/main/java/org/opencord/cordvtn/impl/handler/ManagementInstanceHandler.java
+++ b/src/main/java/org/opencord/cordvtn/impl/handler/ManagementInstanceHandler.java
@@ -29,11 +29,12 @@
 import org.onosproject.net.flow.FlowRule;
 import org.onosproject.net.flow.TrafficSelector;
 import org.onosproject.net.flow.TrafficTreatment;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
 import org.opencord.cordvtn.api.core.Instance;
 import org.opencord.cordvtn.api.core.InstanceHandler;
+import org.opencord.cordvtn.api.core.ServiceNetworkService;
 import org.opencord.cordvtn.api.net.ServiceNetwork;
-import org.opencord.cordvtn.impl.CordVtnNodeManager;
-import org.opencord.cordvtn.impl.CordVtnPipeline;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
 
 import static org.opencord.cordvtn.api.net.ServiceNetwork.NetworkType.MANAGEMENT_HOST;
 import static org.opencord.cordvtn.api.net.ServiceNetwork.NetworkType.MANAGEMENT_LOCAL;
@@ -46,10 +47,13 @@
 public class ManagementInstanceHandler extends AbstractInstanceHandler implements InstanceHandler {
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnPipeline pipeline;
+    protected ServiceNetworkService snetService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
-    protected CordVtnNodeManager nodeManager;
+    protected CordVtnNodeService nodeService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected CordVtnPipeline pipeline;
 
     @Activate
     protected void activate() {
@@ -123,7 +127,7 @@
     }
 
     private void populateHostsManagementRules(Instance instance, boolean install) {
-        PortNumber hostMgmtPort = nodeManager.hostManagementPort(instance.deviceId());
+        PortNumber hostMgmtPort = hostManagementPort(instance.deviceId());
         if (hostMgmtPort == null) {
             log.warn("Can not find host management port in {}", instance.deviceId());
             return;
diff --git a/src/test/java/org/opencord/cordvtn/impl/CordVtnNodeManagerTest.java b/src/test/java/org/opencord/cordvtn/impl/CordVtnNodeManagerTest.java
new file mode 100644
index 0000000..ab27957
--- /dev/null
+++ b/src/test/java/org/opencord/cordvtn/impl/CordVtnNodeManagerTest.java
@@ -0,0 +1,271 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import com.google.common.collect.Lists;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onlab.junit.TestTools;
+import org.onlab.junit.TestUtils;
+import org.onosproject.cluster.ClusterServiceAdapter;
+import org.onosproject.cluster.LeadershipServiceAdapter;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreServiceAdapter;
+import org.onosproject.core.DefaultApplicationId;
+import org.onosproject.event.Event;
+import org.onosproject.net.Device;
+import org.onosproject.net.config.NetworkConfigServiceAdapter;
+import org.onosproject.store.service.TestStorageService;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeEvent;
+import org.opencord.cordvtn.api.node.CordVtnNodeListener;
+
+import java.util.List;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+import static org.opencord.cordvtn.api.node.CordVtnNodeEvent.Type.*;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.COMPLETE;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.INIT;
+import static org.opencord.cordvtn.impl.DefaultCordVtnNode.updatedState;
+
+/**
+ * Unit tests for {@link CordVtnNodeManager}.
+ */
+public class CordVtnNodeManagerTest extends CordVtnNodeTest {
+
+    private static final ApplicationId TEST_APP_ID = new DefaultApplicationId(1, "test");
+    private static final String ERR_SIZE = "Number of nodes did not match";
+    private static final String ERR_NODE = "Node did not match";
+    private static final String ERR_NOT_FOUND = "Node did not exist";
+    private static final String ERR_STATE = "Node state did not match";
+
+    private static final String HOSTNAME_1 = "node-01";
+    private static final String HOSTNAME_2 = "node-02";
+    private static final String HOSTNAME_3 = "node-03";
+
+    private static final Device OF_DEVICE_1 = createDevice(1);
+    private static final Device OF_DEVICE_2 = createDevice(2);
+    private static final Device OF_DEVICE_3 = createDevice(3);
+
+    private static final CordVtnNode NODE_1 = createNode(HOSTNAME_1, OF_DEVICE_1, INIT);
+    private static final CordVtnNode NODE_2 = createNode(HOSTNAME_2, OF_DEVICE_2, INIT);
+    private static final CordVtnNode NODE_3 = createNode(HOSTNAME_3, OF_DEVICE_3, COMPLETE);
+
+    private final TestCordVtnNodeListener testListener = new TestCordVtnNodeListener();
+
+    private CordVtnNodeManager target;
+    private DistributedCordVtnNodeStore nodeStore;
+
+    @Before
+    public void setUp() throws Exception {
+        nodeStore = new DistributedCordVtnNodeStore();
+        TestUtils.setField(nodeStore, "coreService", new TestCoreService());
+        TestUtils.setField(nodeStore, "storageService", new TestStorageService());
+        nodeStore.activate();
+
+        nodeStore.createNode(NODE_2);
+        nodeStore.createNode(NODE_3);
+
+        target = new CordVtnNodeManager();
+        target.coreService = new TestCoreService();
+        target.leadershipService = new TestLeadershipService();
+        target.configService = new TestConfigService();
+        target.clusterService = new TestClusterService();
+        target.nodeStore = nodeStore;
+
+        target.activate();
+        target.addListener(testListener);
+        clearEvents();
+    }
+
+    @After
+    public void tearDown() {
+        target.removeListener(testListener);
+        nodeStore.deactivate();
+        target.deactivate();
+        nodeStore = null;
+        target = null;
+    }
+
+    /**
+     * Checks getting nodes returns correct set of the existing nodes.
+     */
+    @Test
+    public void testGetNodes() {
+        assertEquals(ERR_SIZE, 2, target.nodes().size());
+        assertTrue(ERR_NOT_FOUND, target.nodes().contains(NODE_2));
+        assertTrue(ERR_NOT_FOUND, target.nodes().contains(NODE_3));
+    }
+
+    /**
+     * Checks getting complete nodes method returns correct set of the
+     * existing complete nodes.
+     */
+    @Test
+    public void testGetCompleteNodes() {
+        assertEquals(ERR_SIZE, 1, target.completeNodes().size());
+        assertTrue(ERR_NOT_FOUND, target.completeNodes().contains(NODE_3));
+    }
+
+    /**
+     * Checks if getting node by hostname returns correct node.
+     */
+    @Test
+    public void testGetNodeByHostname() {
+        CordVtnNode node = target.node(HOSTNAME_2);
+        assertEquals(ERR_NODE, NODE_2, node);
+    }
+
+    /**
+     * Checks if getting node by device ID returns correct node.
+     */
+    @Test
+    public void testGetNodeByDeviceId() {
+        CordVtnNode node = target.node(OF_DEVICE_2.id());
+        assertEquals(ERR_NODE, NODE_2, node);
+    }
+
+    /**
+     * Checks if node creation with null fails with exception.
+     */
+    @Test(expected = NullPointerException.class)
+    public void testCreateNullNode() {
+        target.createNode(null);
+    }
+
+    /**
+     * Checks if node removal with null hostname fails with exception.
+     */
+    @Test(expected = IllegalArgumentException.class)
+    public void testRemoveNullHostname() {
+        target.removeNode(null);
+    }
+
+    /**
+     * Checks if node update with null fails with exception.
+     */
+    @Test(expected = NullPointerException.class)
+    public void testUpdateNullNode() {
+        target.updateNode(null);
+    }
+
+    /**
+     * Checks if duplicate node creation fails with exception.
+     */
+    @Test(expected = IllegalArgumentException.class)
+    public void testCreateDuplicateNode() {
+        target.createNode(NODE_1);
+        target.createNode(NODE_1);
+    }
+
+    /**
+     * Checks if unregistered node update fails with exception.
+     */
+    @Test(expected = IllegalArgumentException.class)
+    public void testUpdateUnregisteredNode() {
+        target.updateNode(NODE_1);
+    }
+
+    /**
+     * Checks the basic node creation and removal.
+     */
+    @Test
+    public void testCreateAndRemoveNode() {
+        target.createNode(NODE_1);
+        assertEquals(ERR_SIZE, 3, target.nodes().size());
+        assertTrue(target.node(OF_DEVICE_1.id()) != null);
+
+        target.removeNode(HOSTNAME_1);
+        assertEquals(ERR_SIZE, 2, target.nodes().size());
+        assertTrue(target.node(OF_DEVICE_1.id()) == null);
+
+        validateEvents(NODE_CREATED, NODE_REMOVED);
+    }
+
+    /**
+     * Checks if node complete event is triggered when the node state changes
+     * to COMPLETE.
+     */
+    @Test
+    public void testUpdateNodeStateComplete() {
+        target.updateNode(updatedState(NODE_2, COMPLETE));
+        CordVtnNode node = target.node(HOSTNAME_2);
+        assertEquals(ERR_STATE, COMPLETE, node.state());
+
+        validateEvents(NODE_UPDATED, NODE_COMPLETE);
+    }
+
+    /**
+     * Checks if the node incomplete event is triggered when the node state
+     * falls back from COMPLETE to INIT.
+     */
+    @Test
+    public void testUpdateNodeStateIncomplete() {
+        target.updateNode(updatedState(NODE_3, INIT));
+        CordVtnNode node = target.node(HOSTNAME_3);
+        assertEquals(ERR_STATE, INIT, node.state());
+
+        validateEvents(NODE_UPDATED, NODE_INCOMPLETE);
+    }
+
+    private void clearEvents() {
+        TestTools.delay(100);
+        testListener.events.clear();
+    }
+
+    private void validateEvents(Enum... types) {
+        TestTools.assertAfter(100, () -> {
+            int i = 0;
+            assertEquals("Number of events did not match", types.length, testListener.events.size());
+            for (Event event : testListener.events) {
+                assertEquals("Incorrect event received", types[i], event.type());
+                i++;
+            }
+            testListener.events.clear();
+        });
+    }
+
+    private static class TestCordVtnNodeListener implements CordVtnNodeListener {
+        private List<CordVtnNodeEvent> events = Lists.newArrayList();
+
+        @Override
+        public void event(CordVtnNodeEvent event) {
+            events.add(event);
+        }
+    }
+
+    private static class TestCoreService extends CoreServiceAdapter {
+
+        @Override
+        public ApplicationId registerApplication(String name) {
+            return TEST_APP_ID;
+        }
+    }
+
+    private class TestConfigService extends NetworkConfigServiceAdapter {
+
+    }
+
+    private class TestClusterService extends ClusterServiceAdapter {
+
+    }
+
+    private static class TestLeadershipService extends LeadershipServiceAdapter {
+
+    }
+}
diff --git a/src/test/java/org/opencord/cordvtn/impl/CordVtnNodeTest.java b/src/test/java/org/opencord/cordvtn/impl/CordVtnNodeTest.java
new file mode 100644
index 0000000..1bc666f
--- /dev/null
+++ b/src/test/java/org/opencord/cordvtn/impl/CordVtnNodeTest.java
@@ -0,0 +1,81 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import org.onlab.packet.ChassisId;
+import org.onlab.packet.Ip4Address;
+import org.onlab.packet.TpPort;
+import org.onosproject.net.DefaultAnnotations;
+import org.onosproject.net.DefaultDevice;
+import org.onosproject.net.DefaultPort;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Port;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.provider.ProviderId;
+import org.opencord.cordvtn.api.net.CidrAddr;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeState;
+import org.opencord.cordvtn.api.node.SshAccessInfo;
+
+import static org.onosproject.net.AnnotationKeys.PORT_NAME;
+import static org.onosproject.net.Device.Type.SWITCH;
+
+/**
+ * Provides a set of test CordVtnNode parameters for use with CordVtnNode related tests.
+ */
+public abstract class CordVtnNodeTest {
+
+    public static final SshAccessInfo TEST_SSH_INFO = new SshAccessInfo(
+            Ip4Address.valueOf("192.168.0.1"),
+            TpPort.tpPort(22),
+            "root",
+            "/root/.ssh/id_rsa");
+    public static final CidrAddr TEST_CIDR_ADDR = CidrAddr.valueOf("192.168.0.1/24");
+    public static final String TEST_DATA_IFACE = "eth0";
+    public static final String TEST_VXLAN_IFACE = "vxlan";
+
+    public static Device createDevice(long devIdNum) {
+        return new DefaultDevice(new ProviderId("of", "foo"),
+                DeviceId.deviceId(String.format("of:%016d", devIdNum)),
+                SWITCH,
+                "manufacturer",
+                "hwVersion",
+                "swVersion",
+                "serialNumber",
+                new ChassisId(1));
+    }
+
+    public static Port createPort(Device device, long portNumber, String portName) {
+        return new DefaultPort(device,
+                PortNumber.portNumber(portNumber),
+                true,
+                DefaultAnnotations.builder().set(PORT_NAME, portName).build());
+    }
+
+    public static CordVtnNode createNode(String hostname, Device device, CordVtnNodeState state) {
+        return DefaultCordVtnNode.builder()
+                .hostname(hostname)
+                .hostManagementIp(TEST_CIDR_ADDR)
+                .localManagementIp(TEST_CIDR_ADDR)
+                .dataIp(TEST_CIDR_ADDR)
+                .integrationBridgeId(device.id())
+                .dataInterface(TEST_DATA_IFACE)
+                .sshInfo(TEST_SSH_INFO)
+                .state(state)
+                .build();
+    }
+}
diff --git a/src/test/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeHandlerTest.java b/src/test/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeHandlerTest.java
new file mode 100644
index 0000000..038d2da
--- /dev/null
+++ b/src/test/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeHandlerTest.java
@@ -0,0 +1,599 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import com.google.common.collect.ImmutableSet;
+import com.google.common.collect.Lists;
+import com.google.common.collect.Maps;
+import com.google.common.collect.Sets;
+import com.jcraft.jsch.Session;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.onlab.junit.TestTools;
+import org.onlab.packet.ChassisId;
+import org.onlab.packet.IpAddress;
+import org.onosproject.cluster.ClusterServiceAdapter;
+import org.onosproject.cluster.ControllerNode;
+import org.onosproject.cluster.DefaultControllerNode;
+import org.onosproject.cluster.LeadershipServiceAdapter;
+import org.onosproject.cluster.NodeId;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreServiceAdapter;
+import org.onosproject.core.DefaultApplicationId;
+import org.onosproject.event.DefaultEventSinkRegistry;
+import org.onosproject.event.Event;
+import org.onosproject.event.EventDeliveryService;
+import org.onosproject.event.EventSink;
+import org.onosproject.net.Annotations;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DefaultDevice;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Host;
+import org.onosproject.net.HostId;
+import org.onosproject.net.Port;
+import org.onosproject.net.behaviour.BridgeConfig;
+import org.onosproject.net.behaviour.BridgeDescription;
+import org.onosproject.net.behaviour.InterfaceConfig;
+import org.onosproject.net.config.NetworkConfigServiceAdapter;
+import org.onosproject.net.device.DeviceAdminService;
+import org.onosproject.net.device.DeviceEvent;
+import org.onosproject.net.device.DeviceListener;
+import org.onosproject.net.device.DeviceServiceAdapter;
+import org.onosproject.net.driver.Behaviour;
+import org.onosproject.net.flow.FlowRule;
+import org.onosproject.net.host.HostDescription;
+import org.onosproject.net.host.HostServiceAdapter;
+import org.onosproject.net.provider.ProviderId;
+import org.onosproject.ovsdb.controller.OvsdbClientService;
+import org.onosproject.ovsdb.controller.OvsdbController;
+import org.opencord.cordvtn.api.core.CordVtnPipeline;
+import org.opencord.cordvtn.api.core.InstanceService;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+import org.opencord.cordvtn.api.node.CordVtnNodeAdminService;
+import org.opencord.cordvtn.api.node.CordVtnNodeEvent;
+import org.opencord.cordvtn.api.node.CordVtnNodeListener;
+import org.opencord.cordvtn.api.node.CordVtnNodeService;
+import org.powermock.api.easymock.PowerMock;
+import org.powermock.core.classloader.annotations.PrepareForTest;
+import org.powermock.modules.junit4.PowerMockRunner;
+
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import java.util.stream.Collectors;
+
+import static com.google.common.base.Preconditions.checkState;
+import static org.easymock.EasyMock.*;
+import static org.junit.Assert.assertEquals;
+import static org.onosproject.net.Device.Type.CONTROLLER;
+import static org.onosproject.net.NetTestTools.injectEventDispatcher;
+import static org.onosproject.net.device.DeviceEvent.Type.*;
+import static org.opencord.cordvtn.api.Constants.INTEGRATION_BRIDGE;
+import static org.opencord.cordvtn.api.node.CordVtnNodeEvent.Type.NODE_CREATED;
+import static org.opencord.cordvtn.api.node.CordVtnNodeEvent.Type.NODE_UPDATED;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.*;
+import static org.opencord.cordvtn.impl.RemoteIpCommandUtil.*;
+import static org.powermock.api.easymock.PowerMock.mockStatic;
+
+/**
+ * Unit test for CordVtnNodeHandler which provides cordvtn node bootstrap state machine.
+ */
+@RunWith(PowerMockRunner.class)
+public class DefaultCordVtnNodeHandlerTest extends CordVtnNodeTest {
+
+    private static final String ERR_STATE = "Node state did not match";
+
+    private static final ApplicationId TEST_APP_ID = new DefaultApplicationId(1, "test");
+    private static final NodeId LOCAL_NODE_ID = new NodeId("local");
+    private static final ControllerNode LOCAL_CTRL =
+            new DefaultControllerNode(LOCAL_NODE_ID, IpAddress.valueOf("127.0.0.1"));
+
+    private static final Device OVSDB_DEVICE = new TestDevice(
+            new ProviderId("of", "foo"),
+            DeviceId.deviceId("ovsdb:" + TEST_CIDR_ADDR.ip().toString()),
+            CONTROLLER,
+            "manufacturer",
+            "hwVersion",
+            "swVersion",
+            "serialNumber",
+            new ChassisId(1));
+
+    private static final Device OF_DEVICE_1 = createDevice(1);
+
+    private static final Device OF_DEVICE_2 = createDevice(2);
+    private static final Port OF_DEVICE_2_PORT_1 = createPort(OF_DEVICE_2, 1, TEST_DATA_IFACE);
+    private static final Port OF_DEVICE_2_PORT_2 = createPort(OF_DEVICE_2, 2, TEST_VXLAN_IFACE);
+
+    private static final Device OF_DEVICE_3 = createDevice(3);
+    private static final Port OF_DEVICE_3_PORT_1 = createPort(OF_DEVICE_3, 1, TEST_DATA_IFACE);
+    private static final Port OF_DEVICE_3_PORT_2 = createPort(OF_DEVICE_3, 2, TEST_VXLAN_IFACE);
+
+    private static final Device OF_DEVICE_4 = createDevice(4);
+    private static final Port OF_DEVICE_4_PORT_1 = createPort(OF_DEVICE_4, 1, TEST_DATA_IFACE);
+    private static final Port OF_DEVICE_4_PORT_2 = createPort(OF_DEVICE_4, 2, TEST_VXLAN_IFACE);
+
+    private static final CordVtnNode NODE_1 = createNode("node-01", OF_DEVICE_1, INIT);
+    private static final CordVtnNode NODE_2 = createNode("node-02", OF_DEVICE_2, DEVICE_CREATED);
+    private static final CordVtnNode NODE_3 = createNode("node-03", OF_DEVICE_3, PORT_CREATED);
+    private static final CordVtnNode NODE_4 = createNode("node-04", OF_DEVICE_4, COMPLETE);
+
+    private TestDeviceService deviceService;
+    private TestNodeManager nodeManager;
+    private DefaultCordVtnNodeHandler target;
+
+    @Before
+    public void setUp() throws Exception {
+        this.deviceService = new TestDeviceService();
+        this.nodeManager = new TestNodeManager();
+
+        // add fake ovsdb device
+        this.deviceService.devMap.put(OVSDB_DEVICE.id(), OVSDB_DEVICE);
+
+        // add fake OF devices
+        this.deviceService.devMap.put(OF_DEVICE_1.id(), OF_DEVICE_1);
+        this.deviceService.devMap.put(OF_DEVICE_2.id(), OF_DEVICE_2);
+        this.deviceService.devMap.put(OF_DEVICE_3.id(), OF_DEVICE_3);
+        this.deviceService.devMap.put(OF_DEVICE_4.id(), OF_DEVICE_4);
+
+        // add fake OF ports
+        this.deviceService.portList.add(OF_DEVICE_2_PORT_1);
+        this.deviceService.portList.add(OF_DEVICE_2_PORT_2);
+        this.deviceService.portList.add(OF_DEVICE_3_PORT_1);
+        this.deviceService.portList.add(OF_DEVICE_3_PORT_2);
+        this.deviceService.portList.add(OF_DEVICE_4_PORT_1);
+        this.deviceService.portList.add(OF_DEVICE_4_PORT_2);
+
+        // add fake nodes
+        this.nodeManager.nodeMap.put(OF_DEVICE_1.id(), NODE_1);
+        this.nodeManager.nodeMap.put(OF_DEVICE_2.id(), NODE_2);
+        this.nodeManager.nodeMap.put(OF_DEVICE_3.id(), NODE_3);
+        this.nodeManager.nodeMap.put(OF_DEVICE_4.id(), NODE_4);
+
+        OvsdbClientService mockOvsdbClient = createMock(OvsdbClientService.class);
+        expect(mockOvsdbClient.isConnected())
+                .andReturn(true)
+                .anyTimes();
+        replay(mockOvsdbClient);
+
+        OvsdbController mockOvsdbController = createMock(OvsdbController.class);
+        expect(mockOvsdbController.getOvsdbClient(anyObject()))
+                .andReturn(mockOvsdbClient)
+                .anyTimes();
+        replay(mockOvsdbController);
+
+        DeviceAdminService mockDeviceAdminService = createMock(DeviceAdminService.class);
+        mockDeviceAdminService.removeDevice(anyObject());
+        replay(mockDeviceAdminService);
+
+        target = new DefaultCordVtnNodeHandler();
+        target.coreService = new TestCoreService();
+        target.leadershipService = new TestLeadershipService();
+        target.clusterService = new TestClusterService();
+        target.configService = new TestConfigService();
+        target.deviceService = this.deviceService;
+        target.deviceAdminService = mockDeviceAdminService;
+        target.hostService = new TestHostService();
+        target.ovsdbController = mockOvsdbController;
+        target.nodeService = this.nodeManager;
+        target.nodeAdminService = this.nodeManager;
+        target.instanceService = new TestInstanceService();
+        target.pipelineService = new TestCordVtnPipeline();
+        injectEventDispatcher(target, new TestEventDispatcher());
+        target.activate();
+    }
+
+    @After
+    public void tearDown() {
+        target.deactivate();
+        deviceService = null;
+        nodeManager = null;
+        target = null;
+    }
+
+    /**
+     * Checks if the node state changes from INIT to DEVICE_CREATED when
+     * the integration bridge created.
+     */
+    @Test
+    public void testProcessInitState() {
+        deviceService.addDevice(OF_DEVICE_1);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_1.integrationBridgeId());
+            assertEquals(ERR_STATE, DEVICE_CREATED, current.state());
+        });
+    }
+
+    /**
+     * Checks if the node state changes from DEVICE_CREATED to PORT_CREATED
+     * when the data interface and vxlan interface are added.
+     */
+    @Test
+    public void testProcessDeviceCreatedState() {
+        // Add the data port and check if the state is still in DEVICE_CREAGED
+        deviceService.addPort(OF_DEVICE_2, OF_DEVICE_2_PORT_1);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_2.integrationBridgeId());
+            assertEquals(ERR_STATE, DEVICE_CREATED, current.state());
+        });
+
+        // Add the vxlan port and check if the state changes to PORT_CREATED
+        deviceService.addPort(OF_DEVICE_2, OF_DEVICE_2_PORT_2);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_2.integrationBridgeId());
+            assertEquals(ERR_STATE, PORT_CREATED, current.state());
+        });
+    }
+
+    /**
+     * Checks if the node state changes to COMPLETE when the network interface
+     * configuration is done.
+     */
+    @PrepareForTest(RemoteIpCommandUtil.class)
+    @Test
+    public void testProcessPortCreatedState() {
+        Session mockSession = createMock(Session.class);
+        mockStatic(RemoteIpCommandUtil.class);
+        expect(connect(anyObject())).andReturn(mockSession);
+        expect(getCurrentIps(mockSession, INTEGRATION_BRIDGE)).andReturn(Sets.newHashSet(TEST_CIDR_ADDR.ip()));
+        expect(getCurrentIps(mockSession, TEST_DATA_IFACE)).andReturn(Sets.newHashSet());
+        expect(isInterfaceUp(anyObject(), anyObject())).andReturn(true).anyTimes();
+        RemoteIpCommandUtil.disconnect(anyObject());
+        PowerMock.replay(RemoteIpCommandUtil.class);
+
+        // There's no events for IP address changes on the interfaces, so just
+        // Set node state updated to trigger node bootstrap
+        nodeManager.updateNode(NODE_3);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_3.integrationBridgeId());
+            assertEquals(ERR_STATE, COMPLETE, current.state());
+        });
+    }
+
+    /**
+     * Checks if the node state falls back to INIT when the integration bridge
+     * is removed.
+     */
+    @Test
+    public void testBackToInitStateWhenDeviceRemoved() {
+        // Remove the device from DEVICE_CREATED state node
+        deviceService.removeDevice(OF_DEVICE_2);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_2.integrationBridgeId());
+            assertEquals(ERR_STATE, INIT, current.state());
+        });
+
+        // Remove the device from PORT_CREATED state node
+        deviceService.removeDevice(OF_DEVICE_3);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_3.integrationBridgeId());
+            assertEquals(ERR_STATE, INIT, current.state());
+        });
+
+        // Remove the device from COMPLETE state node
+        deviceService.removeDevice(OF_DEVICE_4);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_4.integrationBridgeId());
+            assertEquals(ERR_STATE, INIT, current.state());
+        });
+    }
+
+    /**
+     * Checks if the node state falls back to DEVICE_CREATED when the ports
+     * are removed.
+     */
+    @Test
+    public void testBackToDeviceCreatedStateWhenPortRemoved() {
+        // Remove the device from PORT_CREATED state node
+        deviceService.removePort(OF_DEVICE_3, OF_DEVICE_3_PORT_1);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_3.integrationBridgeId());
+            assertEquals(ERR_STATE, DEVICE_CREATED, current.state());
+        });
+
+        // Remove the device from COMPLETE state node
+        deviceService.removePort(OF_DEVICE_4, OF_DEVICE_4_PORT_1);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_4.integrationBridgeId());
+            assertEquals(ERR_STATE, DEVICE_CREATED, current.state());
+        });
+    }
+
+    /**
+     * Checks if the node state falls back to PORT_CREATED when the interface
+     * configurations are incomplete.
+     */
+    @PrepareForTest(RemoteIpCommandUtil.class)
+    @Test
+    public void testBackToPortCreatedStateWhenIpRemoved() {
+        // Mocks SSH connection failure
+        mockStatic(RemoteIpCommandUtil.class);
+        expect(connect(anyObject())).andReturn(null);
+        PowerMock.replay(RemoteIpCommandUtil.class);
+
+        // ONOS is not able to detect IP is removed from the interface
+        // Just triggers node update event for the PORT_CREATED node and
+        // check if it stays in PORT_CREATED state
+        nodeManager.updateNode(NODE_3);
+        TestTools.assertAfter(100, () -> {
+            CordVtnNode current = nodeManager.node(NODE_3.integrationBridgeId());
+            assertEquals(ERR_STATE, PORT_CREATED, current.state());
+        });
+    }
+
+    private static final class TestDevice extends DefaultDevice {
+        InterfaceConfig mockInterfaceConfig = createMock(InterfaceConfig.class);
+        BridgeConfig mockBridgeConfig = createMock(BridgeConfig.class);
+
+        private TestDevice(ProviderId providerId,
+                   DeviceId id,
+                   Type type,
+                   String manufacturer,
+                   String hwVersion,
+                   String swVersion,
+                   String serialNumber,
+                   ChassisId chassisId,
+                   Annotations... annotations) {
+            super(providerId,
+                    id,
+                    type,
+                    manufacturer,
+                    hwVersion,
+                    swVersion,
+                    serialNumber,
+                    chassisId,
+                    annotations);
+        }
+
+        @Override
+        @SuppressWarnings("unchecked")
+        public <B extends Behaviour> B as(Class<B> projectionClass) {
+            if (projectionClass.equals(BridgeConfig.class)) {
+                expect(this.mockBridgeConfig.addBridge((BridgeDescription) anyObject()))
+                        .andReturn(true)
+                        .anyTimes();
+                this.mockBridgeConfig.addPort(anyObject(), anyString());
+                replay(mockBridgeConfig);
+                return (B) mockBridgeConfig;
+            } else if (projectionClass.equals(InterfaceConfig.class)) {
+                expect(this.mockInterfaceConfig.addTunnelMode(anyString(), anyObject()))
+                        .andReturn(true)
+                        .anyTimes();
+                replay(mockInterfaceConfig);
+                return (B) mockInterfaceConfig;
+            } else {
+                return null;
+            }
+        }
+
+        @Override
+        public <B extends Behaviour> boolean is(Class<B> projectionClass) {
+            return true;
+        }
+    }
+
+
+    private static class TestCoreService extends CoreServiceAdapter {
+
+        @Override
+        public ApplicationId registerApplication(String name) {
+            return TEST_APP_ID;
+        }
+    }
+
+    private static class TestLeadershipService extends LeadershipServiceAdapter {
+
+        @Override
+        public NodeId getLeader(String path) {
+            return LOCAL_NODE_ID;
+        }
+    }
+
+    private static class TestClusterService extends ClusterServiceAdapter {
+
+        @Override
+        public ControllerNode getLocalNode() {
+            return LOCAL_CTRL;
+        }
+    }
+
+    private static class TestConfigService extends NetworkConfigServiceAdapter {
+
+    }
+
+    private static class TestNodeManager implements CordVtnNodeService, CordVtnNodeAdminService {
+        Map<DeviceId, CordVtnNode> nodeMap = Maps.newHashMap();
+        List<CordVtnNodeListener> listeners = Lists.newArrayList();
+
+        @Override
+        public Set<CordVtnNode> nodes() {
+            return ImmutableSet.copyOf(nodeMap.values());
+        }
+
+        @Override
+        public Set<CordVtnNode> completeNodes() {
+            return null;
+        }
+
+        @Override
+        public CordVtnNode node(String hostname) {
+            return null;
+        }
+
+        @Override
+        public CordVtnNode node(DeviceId deviceId) {
+            return nodeMap.get(deviceId);
+        }
+
+        @Override
+        public void addListener(CordVtnNodeListener listener) {
+            listeners.add(listener);
+        }
+
+        @Override
+        public void removeListener(CordVtnNodeListener listener) {
+            listeners.remove(listener);
+        }
+
+        @Override
+        public void createNode(CordVtnNode node) {
+            nodeMap.put(node.integrationBridgeId(), node);
+            CordVtnNodeEvent event = new CordVtnNodeEvent(NODE_CREATED, node);
+            listeners.forEach(l -> l.event(event));
+        }
+
+        @Override
+        public void updateNode(CordVtnNode node) {
+            nodeMap.put(node.integrationBridgeId(), node);
+            CordVtnNodeEvent event = new CordVtnNodeEvent(NODE_UPDATED, node);
+            listeners.forEach(l -> l.event(event));
+        }
+
+        @Override
+        public CordVtnNode removeNode(String hostname) {
+            return null;
+        }
+    }
+
+    private static class TestDeviceService extends DeviceServiceAdapter {
+        Map<DeviceId, Device> devMap = Maps.newHashMap();
+        List<Port> portList = Lists.newArrayList();
+        List<DeviceListener> listeners = Lists.newArrayList();
+
+        @Override
+        public void addListener(DeviceListener listener) {
+            listeners.add(listener);
+        }
+
+        @Override
+        public void removeListener(DeviceListener listener) {
+            listeners.remove(listener);
+        }
+
+        @Override
+        public Device getDevice(DeviceId deviceId) {
+            return devMap.get(deviceId);
+        }
+
+        @Override
+        public List<Port> getPorts(DeviceId deviceId) {
+            return this.portList.stream()
+                    .filter(p -> p.element().id().equals(deviceId))
+                    .collect(Collectors.toList());
+        }
+
+        @Override
+        public boolean isAvailable(DeviceId deviceId) {
+            return devMap.containsKey(deviceId);
+        }
+
+        void addDevice(Device device) {
+            devMap.put(device.id(), device);
+            DeviceEvent event = new DeviceEvent(DEVICE_ADDED, device);
+            listeners.forEach(l -> l.event(event));
+        }
+
+        void removeDevice(Device device) {
+            devMap.remove(device.id());
+            DeviceEvent event = new DeviceEvent(DEVICE_AVAILABILITY_CHANGED, device);
+            listeners.forEach(l -> l.event(event));
+        }
+
+        void addPort(Device device, Port port) {
+            portList.add(port);
+            DeviceEvent event = new DeviceEvent(PORT_ADDED, device, port);
+            listeners.forEach(l -> l.event(event));
+        }
+
+        void removePort(Device device, Port port) {
+            portList.remove(port);
+            DeviceEvent event = new DeviceEvent(PORT_REMOVED, device, port);
+            listeners.forEach(l -> l.event(event));
+        }
+    }
+
+    private static class TestHostService extends HostServiceAdapter {
+
+        @Override
+        public Iterable<Host> getHosts() {
+            return Lists.newArrayList();
+        }
+    }
+
+    private static class TestInstanceService implements InstanceService {
+
+        @Override
+        public void addInstance(ConnectPoint connectPoint) {
+
+        }
+
+        @Override
+        public void addInstance(HostId hostId, HostDescription description) {
+
+        }
+
+        @Override
+        public void removeInstance(ConnectPoint connectPoint) {
+
+        }
+
+        @Override
+        public void removeInstance(HostId hostId) {
+
+        }
+    }
+
+    private static class TestCordVtnPipeline implements CordVtnPipeline {
+
+        @Override
+        public void initPipeline(CordVtnNode node) {
+
+        }
+
+        @Override
+        public void cleanupPipeline() {
+
+        }
+
+        @Override
+        public void processFlowRule(boolean install, FlowRule rule) {
+
+        }
+    }
+
+    public class TestEventDispatcher extends DefaultEventSinkRegistry
+            implements EventDeliveryService {
+
+        @Override
+        @SuppressWarnings("unchecked")
+        public synchronized void post(Event event) {
+            EventSink sink = getSink(event.getClass());
+            checkState(sink != null, "No sink for event %s", event);
+            sink.process(event);
+        }
+
+        @Override
+        public void setDispatchTimeLimit(long millis) {
+        }
+
+        @Override
+        public long getDispatchTimeLimit() {
+            return 0;
+        }
+    }
+}
diff --git a/src/test/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeTest.java b/src/test/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeTest.java
new file mode 100644
index 0000000..022904e
--- /dev/null
+++ b/src/test/java/org/opencord/cordvtn/impl/DefaultCordVtnNodeTest.java
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.opencord.cordvtn.impl;
+
+import com.google.common.testing.EqualsTester;
+import org.junit.Test;
+import org.onosproject.net.Device;
+import org.opencord.cordvtn.api.node.CordVtnNode;
+
+import static org.onlab.junit.ImmutableClassChecker.assertThatClassIsImmutable;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.COMPLETE;
+import static org.opencord.cordvtn.api.node.CordVtnNodeState.INIT;
+
+/**
+ * Unit test of {@link DefaultCordVtnNode} model entity.
+ */
+public class DefaultCordVtnNodeTest extends CordVtnNodeTest {
+
+    private static final Device OF_DEVICE_1 = createDevice(1);
+    private static final CordVtnNode NODE_1 = createNode("node-01", OF_DEVICE_1, INIT);
+    private static final CordVtnNode NODE_2 = createNode("node-01", OF_DEVICE_1, COMPLETE);
+    private static final CordVtnNode NODE_3 = createNode("node-03", OF_DEVICE_1, INIT);
+
+    @Test
+    public void testImmutability() {
+        assertThatClassIsImmutable(DefaultCordVtnNode.class);
+    }
+
+    @Test
+    public void testEquality() {
+        new EqualsTester().addEqualityGroup(NODE_1, NODE_2)
+                .addEqualityGroup(NODE_3)
+                .testEquals();
+    }
+}