diff --git a/app/src/test/java/org/opencord/maclearner/app/impl/MacLearnerManagerTest.java b/app/src/test/java/org/opencord/maclearner/app/impl/MacLearnerManagerTest.java
index 1e05637..adb59db 100644
--- a/app/src/test/java/org/opencord/maclearner/app/impl/MacLearnerManagerTest.java
+++ b/app/src/test/java/org/opencord/maclearner/app/impl/MacLearnerManagerTest.java
@@ -21,10 +21,17 @@
 import org.onlab.packet.MacAddress;
 import org.onlab.packet.VlanId;
 import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Host;
+import org.onosproject.net.HostId;
+import org.onosproject.net.HostLocation;
+import org.onosproject.net.PortNumber;
 
+import java.io.IOException;
 import java.util.Optional;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
 import static org.junit.Assert.assertTrue;
 
 /**
@@ -33,7 +40,7 @@
 public class MacLearnerManagerTest extends TestBaseMacLearner {
 
     @Before
-    public void setUp() {
+    public void setUp() throws IOException {
         setUpApp();
     }
 
@@ -45,7 +52,12 @@
     private static final MacAddress CLIENT_MAC = MacAddress.valueOf("00:00:00:00:00:01");
     private static final VlanId CLIENT_VLAN = VlanId.vlanId("100");
     private static final VlanId CLIENT_QINQ_VLAN = VlanId.vlanId("200");
-    private static final ConnectPoint CLIENT_CP = ConnectPoint.deviceConnectPoint("of:0000000000000001/1");
+    public static final DeviceId OLT_DEVICE_ID = DeviceId.deviceId("of:0000b86a974385f7");
+    public static final PortNumber UNI_PORT = PortNumber.portNumber(16);
+    public static final ConnectPoint CLIENT_CP = new ConnectPoint(OLT_DEVICE_ID, UNI_PORT);
+    public static final DeviceId AGG_DEVICE_ID = DeviceId.deviceId("of:0000000000000001");
+    public static final PortNumber AGG_OLT_PORT = PortNumber.portNumber(10);
+    public static final PortNumber OLT_NNI_PORT = PortNumber.portNumber(1048576);
 
     @Test
     public void testSingleTagDhcpPacket() {
@@ -71,4 +83,21 @@
         assertEquals(CLIENT_MAC, macAddress.get());
     }
 
+    @Test
+    public void testHostProviding() {
+        packetService.processPacket(new TestDhcpRequestPacketContext(CLIENT_MAC,
+                CLIENT_VLAN,
+                CLIENT_QINQ_VLAN,
+                CLIENT_CP));
+        HostId hostId = HostId.hostId(CLIENT_MAC, CLIENT_QINQ_VLAN);
+        Host host = hostService.getHost(hostId);
+        assertNotNull(host);
+        assertEquals(OLT_DEVICE_ID, host.location().deviceId());
+        assertEquals(UNI_PORT, host.location().port());
+        Optional<HostLocation> optAuxLoc = host.auxLocations().stream().findFirst();
+        assertTrue(optAuxLoc.isPresent());
+        assertEquals(AGG_DEVICE_ID, optAuxLoc.get().deviceId());
+        assertEquals(AGG_OLT_PORT, optAuxLoc.get().port());
+    }
+
 }
diff --git a/app/src/test/java/org/opencord/maclearner/app/impl/TestBaseMacLearner.java b/app/src/test/java/org/opencord/maclearner/app/impl/TestBaseMacLearner.java
index c9d4af5..ffbf0c3 100644
--- a/app/src/test/java/org/opencord/maclearner/app/impl/TestBaseMacLearner.java
+++ b/app/src/test/java/org/opencord/maclearner/app/impl/TestBaseMacLearner.java
@@ -15,29 +15,59 @@
  */
 package org.opencord.maclearner.app.impl;
 
+import com.fasterxml.jackson.databind.JsonNode;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.google.common.collect.ImmutableList;
+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 org.onlab.junit.TestUtils;
+import org.onlab.packet.ChassisId;
 import org.onlab.packet.DHCP;
+import org.onlab.packet.EthType;
 import org.onlab.packet.Ethernet;
 import org.onlab.packet.IPv4;
 import org.onlab.packet.Ip4Address;
+import org.onlab.packet.IpAddress;
 import org.onlab.packet.MacAddress;
 import org.onlab.packet.UDP;
 import org.onlab.packet.VlanId;
 import org.onlab.packet.dhcp.DhcpOption;
 import org.onosproject.cfg.ComponentConfigAdapter;
 import org.onosproject.cfg.ComponentConfigService;
+import org.onosproject.cluster.ClusterServiceAdapter;
+import org.onosproject.cluster.ControllerNode;
+import org.onosproject.cluster.DefaultControllerNode;
+import org.onosproject.cluster.NodeId;
 import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
 import org.onosproject.core.CoreServiceAdapter;
 import org.onosproject.event.DefaultEventSinkRegistry;
 import org.onosproject.event.Event;
 import org.onosproject.event.EventDeliveryService;
 import org.onosproject.event.EventSink;
 import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.DefaultDevice;
+import org.onosproject.net.DefaultHost;
+import org.onosproject.net.DefaultLink;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Host;
+import org.onosproject.net.HostId;
+import org.onosproject.net.HostLocation;
+import org.onosproject.net.Link;
+import org.onosproject.net.config.Config;
+import org.onosproject.net.config.ConfigApplyDelegate;
+import org.onosproject.net.config.basics.HostLearningConfig;
+import org.onosproject.net.config.basics.HostLearningConfigTest;
+import org.onosproject.net.device.DeviceListener;
+import org.onosproject.net.device.DeviceServiceAdapter;
+import org.onosproject.net.host.HostDescription;
+import org.onosproject.net.host.HostProvider;
+import org.onosproject.net.host.HostProviderService;
+import org.onosproject.net.host.HostServiceAdapter;
+import org.onosproject.net.link.LinkServiceAdapter;
 import org.onosproject.net.packet.DefaultInboundPacket;
 import org.onosproject.net.packet.InboundPacket;
 import org.onosproject.net.packet.OutboundPacket;
@@ -45,6 +75,10 @@
 import org.onosproject.net.packet.PacketContextAdapter;
 import org.onosproject.net.packet.PacketProcessor;
 import org.onosproject.net.packet.PacketServiceAdapter;
+import org.onosproject.net.provider.AbstractProviderService;
+import org.onosproject.net.provider.ProviderId;
+import org.onosproject.net.topology.Topology;
+import org.onosproject.net.topology.TopologyServiceAdapter;
 import org.onosproject.store.service.AsyncConsistentMap;
 import org.onosproject.store.service.AsyncDistributedSet;
 import org.onosproject.store.service.AtomicCounter;
@@ -60,6 +94,8 @@
 import org.onosproject.store.service.StorageServiceAdapter;
 import org.onosproject.store.service.Versioned;
 
+import java.io.IOException;
+import java.io.InputStream;
 import java.lang.reflect.Field;
 import java.nio.ByteBuffer;
 import java.util.Collection;
@@ -72,37 +108,85 @@
 import java.util.function.BiFunction;
 
 import static com.google.common.base.Preconditions.checkState;
+import static org.onosproject.cluster.NodeId.nodeId;
+import static org.onosproject.net.NetTestTools.PID;
+import static org.opencord.maclearner.app.impl.MacLearnerManagerTest.AGG_DEVICE_ID;
+import static org.opencord.maclearner.app.impl.MacLearnerManagerTest.AGG_OLT_PORT;
+import static org.opencord.maclearner.app.impl.MacLearnerManagerTest.CLIENT_CP;
+import static org.opencord.maclearner.app.impl.MacLearnerManagerTest.OLT_DEVICE_ID;
+import static org.opencord.maclearner.app.impl.MacLearnerManagerTest.OLT_NNI_PORT;
 
 /**
  * Mac Learner mock services class.
  */
 public abstract class TestBaseMacLearner {
 
+    protected static final String C1 = "C1";
+    protected static final String C2 = "C2";
+    protected static final String C3 = "C3";
+
+    protected static final NodeId CNID_1 = nodeId(C1);
+    protected static final NodeId CNID_2 = nodeId(C2);
+    protected static final NodeId CNID_3 = nodeId(C3);
+
+    protected static final ControllerNode CNODE_1 = new DefaultControllerNode(CNID_1, "10.0.0.1");
+    protected static final ControllerNode CNODE_2 = new DefaultControllerNode(CNID_2, "10.0.0.2");
+    protected static final ControllerNode CNODE_3 = new DefaultControllerNode(CNID_3, "10.0.0.3");
+
     private static final Ip4Address SERVER_IP = Ip4Address.valueOf("10.0.3.253");
     private static final Ip4Address INTERFACE_IP = Ip4Address.valueOf("10.0.3.254");
 
     protected MacLearnerManager macLearnerManager;
-    protected ObjectMapper mapper;
-    protected ApplicationId subject;
+    protected ApplicationId appId;
+    protected HostLearningConfig hostLearningConfig;
 
     protected ComponentConfigService componentConfigService = new MockComponentConfigService();
     protected MockCoreService coreService = new MockCoreService();
     protected MockStorageService storageService = new MockStorageService();
     protected MockPacketService packetService = new MockPacketService();
+    protected MockClusterService clusterService = new MockClusterService();
+    protected MockDeviceService deviceService = new MockDeviceService();
+    protected MockTopologyService topologyService = new MockTopologyService();
+    protected MockLinkService linkService = new MockLinkService();
+    protected MacLearnerHostProvider macLearnerHostProvider = new MacLearnerHostProvider();
+    protected MockHostService hostService = new MockHostService(Sets.newHashSet());
 
-    public void setUpApp() {
+    public void setUpApp() throws IOException {
         macLearnerManager = new MacLearnerManager();
         macLearnerManager.componentConfigService = this.componentConfigService;
         macLearnerManager.coreService = this.coreService;
         macLearnerManager.storageService = this.storageService;
         macLearnerManager.packetService = this.packetService;
+        macLearnerManager.clusterService = this.clusterService;
+        macLearnerManager.deviceService = this.deviceService;
+        macLearnerManager.topologyService = this.topologyService;
+        macLearnerManager.linkService = this.linkService;
+        hostLearningConfig = new HostLearningConfig();
+        InputStream jsonStream = HostLearningConfigTest.class
+                .getResourceAsStream("/host-learning-config.json");
+
+        ConnectPoint subject = CLIENT_CP;
+        String key = CoreService.CORE_APP_NAME;
+        ObjectMapper mapper = new ObjectMapper();
+        JsonNode jsonNode = mapper.readTree(jsonStream);
+        ConfigApplyDelegate delegate = new MockDelegate();
+
+        hostLearningConfig = new HostLearningConfig();
+        hostLearningConfig.init(subject, key, jsonNode, mapper, delegate);
+        macLearnerHostProvider.providerService = new MockHostProviderService(macLearnerHostProvider);
+        macLearnerManager.hostLocService = this.macLearnerHostProvider;
         injectEventDispatcher(macLearnerManager, new MockEventDispatcher());
-        mapper = new ObjectMapper();
-        subject = macLearnerManager.coreService.registerApplication("org.opencord.maclearner");
+        appId = macLearnerManager.coreService.registerApplication("org.opencord.maclearner");
 
         macLearnerManager.activate();
     }
 
+    private class MockDelegate implements ConfigApplyDelegate {
+        @Override
+        public void onApply(Config config) {
+        }
+    }
+
     /**
      * Mocks an instance of {@link ApplicationId} so that the application
      * component under test can query and use its application ID.
@@ -167,6 +251,144 @@
 
     }
 
+    private static class MockClusterService extends ClusterServiceAdapter {
+        private final Map<NodeId, ControllerNode> nodes = new HashMap<>();
+        private final Map<NodeId, ControllerNode.State> states = new HashMap<>();
+
+        MockClusterService() {
+            nodes.put(CNODE_1.id(), CNODE_1);
+            nodes.put(CNODE_2.id(), CNODE_2);
+            nodes.put(CNODE_3.id(), CNODE_3);
+
+            states.put(CNODE_1.id(), ControllerNode.State.READY);
+            states.put(CNODE_2.id(), ControllerNode.State.ACTIVE);
+            states.put(CNODE_3.id(), ControllerNode.State.ACTIVE);
+        }
+
+        @Override
+        public Set<ControllerNode> getNodes() {
+            return ImmutableSet.copyOf(nodes.values());
+        }
+
+        @Override
+        public ControllerNode getNode(NodeId nodeId) {
+            return nodes.get(nodeId);
+        }
+
+        @Override
+        public ControllerNode.State getState(NodeId nodeId) {
+            return states.get(nodeId);
+        }
+    }
+
+    /**
+     * Mocks the device service of ONOS so that the application under test can
+     * register listeners.
+     */
+    protected static class MockHostService extends HostServiceAdapter {
+        private Set<Host> hosts;
+
+        MockHostService(Set<Host> hosts) {
+            this.hosts = ImmutableSet.copyOf(hosts);
+        }
+
+        @Override
+        public Set<Host> getHosts() {
+            return hosts;
+        }
+
+        @Override
+        public Host getHost(HostId hostId) {
+            return hosts.stream().filter(host -> hostId.equals(host.id())).findFirst().orElse(null);
+        }
+    }
+
+    /**
+     * Mocks the device service of ONOS so that the application under test can
+     * register listeners.
+     */
+    private static class MockDeviceService extends DeviceServiceAdapter {
+
+        private List<DeviceListener> listeners = Lists.newArrayList();
+
+        @Override
+        public Device getDevice(DeviceId deviceId) {
+            if (deviceId.equals(OLT_DEVICE_ID)) {
+                return new DefaultDevice(null, OLT_DEVICE_ID, Device.Type.SWITCH,
+                        "VOLTHA Project", "open_pon", "open_pon",
+                        "BBSIM_OLT_1", new ChassisId("a0a0a0a0a01"));
+            } else {
+                return null;
+            }
+        }
+
+        @Override
+        public void addListener(DeviceListener listener) {
+            listeners.add(listener);
+        }
+
+        @Override
+        public void removeListener(DeviceListener listener) {
+            listeners.remove(listener);
+        }
+    }
+
+    /**
+     * Mocks the topology service of ONOS so that the application under test can
+     * check fake topology.
+     */
+    private static class MockTopologyService extends TopologyServiceAdapter {
+
+        private final Topology topology = new MockTopology();
+
+        @Override
+        public Topology currentTopology() {
+            return topology;
+        }
+
+        @Override
+        public boolean isInfrastructure(Topology topology, ConnectPoint connectPoint) {
+            return false;
+        }
+    }
+
+    private static class MockTopology implements Topology {
+        @Override
+        public long time() {
+            return 11111L;
+        }
+
+        @Override
+        public long creationTime() {
+            return 22222L;
+        }
+
+        @Override
+        public long computeCost() {
+            return 0;
+        }
+
+        @Override
+        public int clusterCount() {
+            return 2;
+        }
+
+        @Override
+        public int deviceCount() {
+            return 6;
+        }
+
+        @Override
+        public int linkCount() {
+            return 4;
+        }
+
+        @Override
+        public ProviderId providerId() {
+            return ProviderId.NONE;
+        }
+    }
+
     /**
      * Mocks the storage service of ONOS so that the application under test can
      * use consistent maps.
@@ -388,6 +610,24 @@
     }
 
     /**
+     * Mocks the link service of ONOS so that the application under test can
+     * observe links.
+     */
+    public static class MockLinkService extends LinkServiceAdapter {
+
+        Link link = DefaultLink.builder()
+                .type(Link.Type.DIRECT)
+                .providerId(PID)
+                .src(new ConnectPoint(OLT_DEVICE_ID, OLT_NNI_PORT))
+                .dst(new ConnectPoint(AGG_DEVICE_ID, AGG_OLT_PORT)).build();
+
+        @Override
+        public Set<Link> getDeviceLinks(DeviceId deviceId) {
+            return Sets.newHashSet(link);
+        }
+    }
+
+    /**
      * Implements event delivery system that delivers events synchronously, or
      * in-line with the post method invocation.
      */
@@ -429,6 +669,60 @@
     }
 
     /**
+     * Mock HostProviderService.
+     */
+    private class MockHostProviderService
+            extends AbstractProviderService<HostProvider>
+            implements HostProviderService {
+        private HostId hostId = null;
+        private HostDescription hostDescription = null;
+        private String event = null;
+
+        public MockHostProviderService(HostProvider provider) {
+            super(provider);
+        }
+
+        @Override
+        public void hostDetected(HostId hostId, HostDescription hostDescription, boolean replaceIps) {
+            this.hostId = hostId;
+            this.hostDescription = hostDescription;
+            this.event = "hostDetected";
+            Set<Host> previousHosts = Sets.newHashSet(hostService.getHosts());
+            previousHosts.add(new DefaultHost(provider().id(), hostId, hostDescription.hwAddress(),
+                    hostDescription.vlan(), hostDescription.locations(), hostDescription.auxLocations(),
+                    hostDescription.ipAddress(), VlanId.NONE,
+                    EthType.EtherType.UNKNOWN.ethType(), false, false));
+            hostService = new MockHostService(previousHosts);
+        }
+
+        @Override
+        public void hostVanished(HostId hostId) {
+            this.hostId = hostId;
+            this.event = "hostVanished";
+            Set<Host> previousHosts = Sets.newHashSet(hostService.getHosts());
+            Host removedHost = hostService.getHost(hostId);
+            previousHosts.remove(removedHost);
+            hostService = new MockHostService(previousHosts);
+        }
+
+        @Override
+        public void removeIpFromHost(HostId hostId, IpAddress ipAddress) {
+            // not implemented
+        }
+
+        @Override
+        public void removeLocationFromHost(HostId hostId, HostLocation location) {
+            // not implemented
+        }
+
+        public void clear() {
+            this.hostId = null;
+            this.hostDescription = null;
+            this.event = null;
+        }
+    }
+
+    /**
      * Generates DHCP REQUEST packet.
      */
     protected static class TestDhcpRequestPacketContext extends PacketContextAdapter {