[VOL-3836] Extract the OLT pipeliners from ONOS

Change-Id: I0dc99aabcb17b46fc5dc8bbe8e3bbd5ece52058a
diff --git a/impl/src/main/java/org/opencord/olt/driver/OltPipeline.java b/impl/src/main/java/org/opencord/olt/driver/OltPipeline.java
new file mode 100644
index 0000000..d5beb63
--- /dev/null
+++ b/impl/src/main/java/org/opencord/olt/driver/OltPipeline.java
@@ -0,0 +1,1291 @@
+/*
+ * Copyright 2016-present Open Networking Foundation
+ *
+ * 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.olt.driver;
+
+import com.google.common.cache.Cache;
+import com.google.common.cache.CacheBuilder;
+import com.google.common.cache.RemovalCause;
+import com.google.common.cache.RemovalNotification;
+import com.google.common.collect.ImmutableList;
+import com.google.common.collect.Lists;
+import org.apache.commons.lang3.tuple.ImmutablePair;
+import org.apache.commons.lang3.tuple.Pair;
+import org.onlab.osgi.ServiceDirectory;
+import org.onlab.packet.EthType;
+import org.onlab.packet.IPv4;
+import org.onlab.packet.IPv6;
+import org.onlab.packet.IpPrefix;
+import org.onlab.packet.VlanId;
+import org.onlab.util.AbstractAccumulator;
+import org.onlab.util.Accumulator;
+import org.onlab.util.KryoNamespace;
+import org.onosproject.core.ApplicationId;
+import org.onosproject.core.CoreService;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.PortNumber;
+import org.onosproject.net.behaviour.NextGroup;
+import org.onosproject.net.behaviour.Pipeliner;
+import org.onosproject.net.behaviour.PipelinerContext;
+import org.onosproject.net.driver.AbstractHandlerBehaviour;
+import org.onosproject.net.driver.Driver;
+import org.onosproject.net.flow.DefaultFlowRule;
+import org.onosproject.net.flow.DefaultTrafficSelector;
+import org.onosproject.net.flow.DefaultTrafficTreatment;
+import org.onosproject.net.flow.FlowRule;
+import org.onosproject.net.flow.FlowRuleOperations;
+import org.onosproject.net.flow.FlowRuleOperationsContext;
+import org.onosproject.net.flow.FlowRuleService;
+import org.onosproject.net.flow.TrafficSelector;
+import org.onosproject.net.flow.TrafficTreatment;
+import org.onosproject.net.flow.criteria.Criteria;
+import org.onosproject.net.flow.criteria.Criterion;
+import org.onosproject.net.flow.criteria.EthTypeCriterion;
+import org.onosproject.net.flow.criteria.IPCriterion;
+import org.onosproject.net.flow.criteria.IPProtocolCriterion;
+import org.onosproject.net.flow.criteria.PortCriterion;
+import org.onosproject.net.flow.criteria.UdpPortCriterion;
+import org.onosproject.net.flow.criteria.VlanIdCriterion;
+import org.onosproject.net.flow.instructions.Instruction;
+import org.onosproject.net.flow.instructions.Instructions;
+import org.onosproject.net.flow.instructions.L2ModificationInstruction;
+import org.onosproject.net.flowobjective.FilteringObjective;
+import org.onosproject.net.flowobjective.FlowObjectiveStore;
+import org.onosproject.net.flowobjective.ForwardingObjective;
+import org.onosproject.net.flowobjective.NextObjective;
+import org.onosproject.net.flowobjective.Objective;
+import org.onosproject.net.flowobjective.ObjectiveError;
+import org.onosproject.net.group.DefaultGroupBucket;
+import org.onosproject.net.group.DefaultGroupDescription;
+import org.onosproject.net.group.DefaultGroupKey;
+import org.onosproject.net.group.Group;
+import org.onosproject.net.group.GroupBucket;
+import org.onosproject.net.group.GroupBuckets;
+import org.onosproject.net.group.GroupDescription;
+import org.onosproject.net.group.GroupEvent;
+import org.onosproject.net.group.GroupKey;
+import org.onosproject.net.group.GroupListener;
+import org.onosproject.net.group.GroupService;
+import org.onosproject.store.serializers.KryoNamespaces;
+import org.onosproject.store.service.StorageService;
+import org.slf4j.Logger;
+
+import java.util.Arrays;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.concurrent.ScheduledExecutorService;
+import java.util.Timer;
+import java.util.concurrent.TimeUnit;
+import java.util.stream.Collectors;
+
+import static org.onosproject.core.CoreService.CORE_APP_NAME;
+import static java.util.concurrent.Executors.newSingleThreadScheduledExecutor;
+import static org.onlab.util.Tools.groupedThreads;
+import static org.slf4j.LoggerFactory.getLogger;
+
+/**
+ * Pipeliner for OLT device.
+ */
+
+public class OltPipeline extends AbstractHandlerBehaviour implements Pipeliner {
+
+    private static final Integer QQ_TABLE = 1;
+    private static final int NO_ACTION_PRIORITY = 500;
+    private static final String DOWNSTREAM = "downstream";
+    private static final String UPSTREAM = "upstream";
+    private final Logger log = getLogger(getClass());
+
+    private ServiceDirectory serviceDirectory;
+    private FlowRuleService flowRuleService;
+    private GroupService groupService;
+    private CoreService coreService;
+    private StorageService storageService;
+
+    private DeviceId deviceId;
+    private ApplicationId appId;
+
+
+    protected FlowObjectiveStore flowObjectiveStore;
+
+    private Cache<GroupKey, NextObjective> pendingGroups;
+
+    protected static KryoNamespace appKryo = new KryoNamespace.Builder()
+            .register(KryoNamespaces.API)
+            .register(GroupKey.class)
+            .register(DefaultGroupKey.class)
+            .register(OltPipelineGroup.class)
+            .build("OltPipeline");
+
+    private static final Timer TIMER = new Timer("filterobj-batching");
+    private Accumulator<Pair<FilteringObjective, FlowRule>> accumulator;
+
+    // accumulator executor service
+    private ScheduledExecutorService accumulatorExecutorService
+            = newSingleThreadScheduledExecutor(groupedThreads("OltPipeliner", "acc-%d", log));
+
+    @Override
+    public void init(DeviceId deviceId, PipelinerContext context) {
+        log.debug("Initiate OLT pipeline");
+        this.serviceDirectory = context.directory();
+        this.deviceId = deviceId;
+
+        flowRuleService = serviceDirectory.get(FlowRuleService.class);
+        coreService = serviceDirectory.get(CoreService.class);
+        groupService = serviceDirectory.get(GroupService.class);
+        flowObjectiveStore = context.store();
+        storageService = serviceDirectory.get(StorageService.class);
+
+        appId = coreService.registerApplication(
+                "org.onosproject.driver.OLTPipeline");
+
+        // Init the accumulator, if enabled
+        if (isAccumulatorEnabled()) {
+            log.debug("Building accumulator with maxObjs {}, batchMs {}, idleMs {}",
+                      context.accumulatorMaxObjectives(), context.accumulatorMaxBatchMillis(),
+                      context.accumulatorMaxIdleMillis());
+            accumulator = new ObjectiveAccumulator(context.accumulatorMaxObjectives(),
+                                                   context.accumulatorMaxBatchMillis(),
+                                                   context.accumulatorMaxIdleMillis());
+        }
+
+
+        pendingGroups = CacheBuilder.newBuilder()
+                .expireAfterWrite(20, TimeUnit.SECONDS)
+                .removalListener((RemovalNotification<GroupKey, NextObjective> notification) -> {
+                    if (notification.getCause() == RemovalCause.EXPIRED) {
+                        fail(notification.getValue(), ObjectiveError.GROUPINSTALLATIONFAILED);
+                    }
+                }).build();
+
+        groupService.addListener(new InnerGroupListener());
+
+    }
+
+    public boolean isAccumulatorEnabled() {
+        Driver driver = super.data().driver();
+        // we cannot determine the property
+        if (driver == null) {
+            return false;
+        }
+        return Boolean.parseBoolean(driver.getProperty(ACCUMULATOR_ENABLED));
+    }
+
+    @Override
+    public void filter(FilteringObjective filter) {
+        Instructions.OutputInstruction output;
+
+        if (filter.meta() != null && !filter.meta().immediate().isEmpty()) {
+            output = (Instructions.OutputInstruction) filter.meta().immediate().stream()
+                    .filter(t -> t.type().equals(Instruction.Type.OUTPUT))
+                    .limit(1)
+                    .findFirst().get();
+
+            if (output == null || !output.port().equals(PortNumber.CONTROLLER)) {
+                log.warn("OLT can only filter packet to controller");
+                fail(filter, ObjectiveError.UNSUPPORTED);
+                return;
+            }
+        } else {
+            fail(filter, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+        if (filter.key().type() != Criterion.Type.IN_PORT) {
+            fail(filter, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+        EthTypeCriterion ethType = (EthTypeCriterion)
+                filterForCriterion(filter.conditions(), Criterion.Type.ETH_TYPE);
+
+        if (ethType == null) {
+            fail(filter, ObjectiveError.BADPARAMS);
+            return;
+        }
+        Optional<Instruction> vlanId = filter.meta().immediate().stream()
+                .filter(t -> t.type().equals(Instruction.Type.L2MODIFICATION)
+                        && ((L2ModificationInstruction) t).subtype()
+                        .equals(L2ModificationInstruction.L2SubType.VLAN_ID))
+                .limit(1)
+                .findFirst();
+
+        Optional<Instruction> vlanPcp = filter.meta().immediate().stream()
+                .filter(t -> t.type().equals(Instruction.Type.L2MODIFICATION)
+                        && ((L2ModificationInstruction) t).subtype()
+                        .equals(L2ModificationInstruction.L2SubType.VLAN_PCP))
+                .limit(1)
+                .findFirst();
+
+        Optional<Instruction> vlanPush = filter.meta().immediate().stream()
+                .filter(t -> t.type().equals(Instruction.Type.L2MODIFICATION)
+                        && ((L2ModificationInstruction) t).subtype()
+                        .equals(L2ModificationInstruction.L2SubType.VLAN_PUSH))
+                .limit(1)
+                .findFirst();
+
+        if (ethType.ethType().equals(EthType.EtherType.EAPOL.ethType())) {
+
+            if (vlanId.isEmpty() || vlanPush.isEmpty()) {
+                log.warn("Missing EAPOL vlan or vlanPush");
+                fail(filter, ObjectiveError.BADPARAMS);
+                return;
+            }
+            provisionEthTypeBasedFilter(filter, ethType, output,
+                                        (L2ModificationInstruction) vlanId.get(),
+                                        (L2ModificationInstruction) vlanPush.get());
+        } else if (ethType.ethType().equals(EthType.EtherType.PPPoED.ethType()))  {
+            provisionPPPoED(filter, ethType, vlanId.orElse(null), vlanPcp.orElse(null), output);
+        } else if (ethType.ethType().equals(EthType.EtherType.LLDP.ethType())) {
+            provisionEthTypeBasedFilter(filter, ethType, output, null, null);
+        } else if (ethType.ethType().equals(EthType.EtherType.IPV4.ethType())) {
+            IPProtocolCriterion ipProto = (IPProtocolCriterion)
+                    filterForCriterion(filter.conditions(), Criterion.Type.IP_PROTO);
+            if (ipProto == null) {
+                log.warn("OLT can only filter IGMP and DHCP");
+                fail(filter, ObjectiveError.UNSUPPORTED);
+                return;
+            }
+            if (ipProto.protocol() == IPv4.PROTOCOL_IGMP) {
+                provisionIgmp(filter, ethType, ipProto, output,
+                              vlanId.orElse(null),
+                              vlanPcp.orElse(null));
+            } else if (ipProto.protocol() == IPv4.PROTOCOL_UDP) {
+                UdpPortCriterion udpSrcPort = (UdpPortCriterion)
+                        filterForCriterion(filter.conditions(), Criterion.Type.UDP_SRC);
+
+                UdpPortCriterion udpDstPort = (UdpPortCriterion)
+                        filterForCriterion(filter.conditions(), Criterion.Type.UDP_DST);
+
+                if ((udpSrcPort.udpPort().toInt() == 67 && udpDstPort.udpPort().toInt() == 68) ||
+                        (udpSrcPort.udpPort().toInt() == 68 && udpDstPort.udpPort().toInt() == 67)) {
+                    provisionDhcp(filter, ethType, ipProto, udpSrcPort, udpDstPort, vlanId.orElse(null),
+                                  vlanPcp.orElse(null), output);
+                } else {
+                    log.warn("Filtering rule with unsupported UDP src {} or dst {} port", udpSrcPort, udpDstPort);
+                    fail(filter, ObjectiveError.UNSUPPORTED);
+                }
+            } else {
+                log.warn("Currently supporting only IGMP and DHCP filters for IPv4 packets");
+                fail(filter, ObjectiveError.UNSUPPORTED);
+            }
+        } else if (ethType.ethType().equals(EthType.EtherType.IPV6.ethType())) {
+            IPProtocolCriterion ipProto = (IPProtocolCriterion)
+                    filterForCriterion(filter.conditions(), Criterion.Type.IP_PROTO);
+            if (ipProto == null) {
+                log.warn("OLT can only filter DHCP");
+                fail(filter, ObjectiveError.UNSUPPORTED);
+                return;
+            }
+            if (ipProto.protocol() == IPv6.PROTOCOL_UDP) {
+                UdpPortCriterion udpSrcPort = (UdpPortCriterion)
+                        filterForCriterion(filter.conditions(), Criterion.Type.UDP_SRC);
+
+                UdpPortCriterion udpDstPort = (UdpPortCriterion)
+                        filterForCriterion(filter.conditions(), Criterion.Type.UDP_DST);
+
+                if ((udpSrcPort.udpPort().toInt() == 546 && udpDstPort.udpPort().toInt() == 547) ||
+                        (udpSrcPort.udpPort().toInt() == 547 && udpDstPort.udpPort().toInt() == 546)) {
+                    provisionDhcp(filter, ethType, ipProto, udpSrcPort, udpDstPort, vlanId.orElse(null),
+                                  vlanPcp.orElse(null), output);
+                } else {
+                    log.warn("Filtering rule with unsupported UDP src {} or dst {} port", udpSrcPort, udpDstPort);
+                    fail(filter, ObjectiveError.UNSUPPORTED);
+                }
+            } else {
+                log.warn("Currently supporting only DHCP filters for IPv6 packets");
+                fail(filter, ObjectiveError.UNSUPPORTED);
+            }
+        } else {
+            log.warn("\nOnly the following are Supported in OLT for filter ->\n"
+                             + "ETH TYPE : EAPOL, LLDP and IPV4\n"
+                             + "IPV4 TYPE: IGMP and UDP (for DHCP)"
+                             + "IPV6 TYPE: UDP (for DHCP)");
+            fail(filter, ObjectiveError.UNSUPPORTED);
+        }
+
+    }
+
+
+    @Override
+    public void forward(ForwardingObjective fwd) {
+        log.debug("Installing forwarding objective {}", fwd);
+        if (checkForMulticast(fwd)) {
+            processMulticastRule(fwd);
+            return;
+        }
+
+        TrafficTreatment treatment = fwd.treatment();
+
+        List<Instruction> instructions = treatment.allInstructions();
+
+        Optional<Instruction> vlanInstruction = instructions.stream()
+                .filter(i -> i.type() == Instruction.Type.L2MODIFICATION)
+                .filter(i -> ((L2ModificationInstruction) i).subtype() ==
+                        L2ModificationInstruction.L2SubType.VLAN_PUSH ||
+                        ((L2ModificationInstruction) i).subtype() ==
+                                L2ModificationInstruction.L2SubType.VLAN_POP)
+                .findAny();
+
+
+        if (!vlanInstruction.isPresent()) {
+            installNoModificationRules(fwd);
+        } else {
+            L2ModificationInstruction vlanIns =
+                    (L2ModificationInstruction) vlanInstruction.get();
+            if (vlanIns.subtype() == L2ModificationInstruction.L2SubType.VLAN_PUSH) {
+                installUpstreamRules(fwd);
+            } else if (vlanIns.subtype() == L2ModificationInstruction.L2SubType.VLAN_POP) {
+                installDownstreamRules(fwd);
+            } else {
+                log.error("Unknown OLT operation: {}", fwd);
+                fail(fwd, ObjectiveError.UNSUPPORTED);
+                return;
+            }
+        }
+
+        pass(fwd);
+
+    }
+
+
+    @Override
+    public void next(NextObjective nextObjective) {
+        if (nextObjective.type() != NextObjective.Type.BROADCAST) {
+            log.error("OLT only supports broadcast groups.");
+            fail(nextObjective, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+        if (nextObjective.next().size() != 1 && !nextObjective.op().equals(Objective.Operation.REMOVE)) {
+            log.error("OLT only supports singleton broadcast groups.");
+            fail(nextObjective, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+        Optional<TrafficTreatment> treatmentOpt = nextObjective.next().stream().findFirst();
+        if (treatmentOpt.isEmpty() && !nextObjective.op().equals(Objective.Operation.REMOVE)) {
+            log.error("Next objective {} does not have a treatment", nextObjective);
+            fail(nextObjective, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+        GroupKey key = new DefaultGroupKey(appKryo.serialize(nextObjective.id()));
+
+        pendingGroups.put(key, nextObjective);
+        log.trace("NextObjective Operation {}", nextObjective.op());
+        switch (nextObjective.op()) {
+            case ADD:
+                GroupDescription groupDesc =
+                        new DefaultGroupDescription(deviceId,
+                                                    GroupDescription.Type.ALL,
+                                                    new GroupBuckets(
+                                                            Collections.singletonList(
+                                                                    buildBucket(treatmentOpt.get()))),
+                                                    key,
+                                                    null,
+                                                    nextObjective.appId());
+                groupService.addGroup(groupDesc);
+                break;
+            case REMOVE:
+                groupService.removeGroup(deviceId, key, nextObjective.appId());
+                break;
+            case ADD_TO_EXISTING:
+                groupService.addBucketsToGroup(deviceId, key,
+                                               new GroupBuckets(
+                                                       Collections.singletonList(
+                                                               buildBucket(treatmentOpt.get()))),
+                                               key, nextObjective.appId());
+                break;
+            case REMOVE_FROM_EXISTING:
+                groupService.removeBucketsFromGroup(deviceId, key,
+                                                    new GroupBuckets(
+                                                            Collections.singletonList(
+                                                                    buildBucket(treatmentOpt.get()))),
+                                                    key, nextObjective.appId());
+                break;
+            default:
+                log.warn("Unknown next objective operation: {}", nextObjective.op());
+        }
+
+
+    }
+
+    private GroupBucket buildBucket(TrafficTreatment treatment) {
+        return DefaultGroupBucket.createAllGroupBucket(treatment);
+    }
+
+    private void processMulticastRule(ForwardingObjective fwd) {
+        if (fwd.nextId() == null) {
+            log.error("Multicast objective does not have a next id");
+            fail(fwd, ObjectiveError.BADPARAMS);
+        }
+
+        GroupKey key = getGroupForNextObjective(fwd.nextId());
+
+        if (key == null) {
+            log.error("Group for forwarding objective missing: {}", fwd);
+            fail(fwd, ObjectiveError.GROUPMISSING);
+        }
+
+        Group group = groupService.getGroup(deviceId, key);
+        TrafficTreatment treatment =
+                buildTreatment(Instructions.createGroup(group.id()));
+
+        TrafficSelector.Builder selectorBuilder = buildIpv4SelectorForMulticast(fwd);
+
+        FlowRule rule = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .forTable(0)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(selectorBuilder.build())
+                .withTreatment(treatment)
+                .build();
+
+        FlowRuleOperations.Builder builder = FlowRuleOperations.builder();
+        switch (fwd.op()) {
+
+            case ADD:
+                builder.add(rule);
+                break;
+            case REMOVE:
+                builder.remove(rule);
+                break;
+            case ADD_TO_EXISTING:
+            case REMOVE_FROM_EXISTING:
+                break;
+            default:
+                log.warn("Unknown forwarding operation: {}", fwd.op());
+        }
+
+        applyFlowRules(ImmutableList.of(fwd), builder);
+
+
+    }
+
+    private TrafficSelector.Builder buildIpv4SelectorForMulticast(ForwardingObjective fwd) {
+        TrafficSelector.Builder builderToUpdate = DefaultTrafficSelector.builder();
+
+        Optional<Criterion> vlanIdCriterion = readFromSelector(fwd.meta(), Criterion.Type.VLAN_VID);
+        if (vlanIdCriterion.isPresent()) {
+            VlanId assignedVlan = ((VlanIdCriterion) vlanIdCriterion.get()).vlanId();
+            builderToUpdate.matchVlanId(assignedVlan);
+        }
+
+        Optional<Criterion> innerVlanIdCriterion = readFromSelector(fwd.meta(), Criterion.Type.INNER_VLAN_VID);
+        if (innerVlanIdCriterion.isPresent()) {
+            VlanId assignedInnerVlan = ((VlanIdCriterion) innerVlanIdCriterion.get()).vlanId();
+            builderToUpdate.matchMetadata(assignedInnerVlan.toShort());
+        }
+
+        Optional<Criterion> ethTypeCriterion = readFromSelector(fwd.selector(), Criterion.Type.ETH_TYPE);
+        if (ethTypeCriterion.isPresent()) {
+            EthType ethType = ((EthTypeCriterion) ethTypeCriterion.get()).ethType();
+            builderToUpdate.matchEthType(ethType.toShort());
+        }
+
+        Optional<Criterion> ipv4DstCriterion = readFromSelector(fwd.selector(), Criterion.Type.IPV4_DST);
+        if (ipv4DstCriterion.isPresent()) {
+            IpPrefix ipv4Dst = ((IPCriterion) ipv4DstCriterion.get()).ip();
+            builderToUpdate.matchIPDst(ipv4Dst);
+        }
+
+        return builderToUpdate;
+    }
+
+    static Optional<Criterion> readFromSelector(TrafficSelector selector, Criterion.Type type) {
+        if (selector == null) {
+            return Optional.empty();
+        }
+        Criterion criterion = selector.getCriterion(type);
+        return (criterion == null)
+                ? Optional.empty() : Optional.of(criterion);
+    }
+
+    private boolean checkForMulticast(ForwardingObjective fwd) {
+
+        IPCriterion ip = (IPCriterion) filterForCriterion(fwd.selector().criteria(),
+                                                          Criterion.Type.IPV4_DST);
+
+        if (ip == null) {
+            return false;
+        }
+
+        return ip.ip().isMulticast();
+
+    }
+
+    private GroupKey getGroupForNextObjective(Integer nextId) {
+        NextGroup next = flowObjectiveStore.getNextGroup(nextId);
+        return appKryo.deserialize(next.data());
+
+    }
+
+    private void installNoModificationRules(ForwardingObjective fwd) {
+        Instructions.OutputInstruction output = (Instructions.OutputInstruction) fetchOutput(fwd, DOWNSTREAM);
+        Instructions.MetadataInstruction writeMetadata = fetchWriteMetadata(fwd);
+        Instructions.MeterInstruction meter = (Instructions.MeterInstruction) fetchMeter(fwd);
+
+        TrafficSelector selector = fwd.selector();
+
+        Criterion inport = selector.getCriterion(Criterion.Type.IN_PORT);
+        Criterion outerVlan = selector.getCriterion(Criterion.Type.VLAN_VID);
+        Criterion innerVlan = selector.getCriterion(Criterion.Type.INNER_VLAN_VID);
+
+        if (inport == null || output == null || innerVlan == null || outerVlan == null) {
+            // Avoid logging a non-error from lldp, bbdp and eapol core flows.
+            if (!fwd.appId().name().equals(CORE_APP_NAME)) {
+                log.error("Forwarding objective is underspecified: {}", fwd);
+            } else {
+                log.debug("Not installing unsupported core generated flow {}", fwd);
+            }
+            fail(fwd, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+
+        FlowRule.Builder outer = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(buildSelector(inport, outerVlan))
+                .withTreatment(buildTreatment(output, writeMetadata, meter));
+
+        applyRules(fwd, outer);
+    }
+
+    private void installDownstreamRules(ForwardingObjective fwd) {
+        Instructions.OutputInstruction output = (Instructions.OutputInstruction) fetchOutput(fwd, DOWNSTREAM);
+
+        if (output == null) {
+            return;
+        }
+
+        TrafficSelector selector = fwd.selector();
+
+        Criterion outerVlan = selector.getCriterion(Criterion.Type.VLAN_VID);
+        Criterion outerPbit = selector.getCriterion(Criterion.Type.VLAN_PCP);
+        Criterion innerVlanCriterion = selector.getCriterion(Criterion.Type.INNER_VLAN_VID);
+        Criterion inport = selector.getCriterion(Criterion.Type.IN_PORT);
+        Criterion dstMac = selector.getCriterion(Criterion.Type.ETH_DST);
+
+        if (outerVlan == null || innerVlanCriterion == null || inport == null) {
+            // Avoid logging a non-error from lldp, bbdp and eapol core flows.
+            if (!fwd.appId().name().equals(CORE_APP_NAME)) {
+                log.error("Forwarding objective is underspecified: {}", fwd);
+            } else {
+                log.debug("Not installing unsupported core generated flow {}", fwd);
+            }
+            fail(fwd, ObjectiveError.BADPARAMS);
+            return;
+        }
+
+        VlanId innerVlan = ((VlanIdCriterion) innerVlanCriterion).vlanId();
+        Criterion innerVid = Criteria.matchVlanId(innerVlan);
+
+        // In the case where the C-tag is the same for all the subscribers,
+        // we add a metadata with the outport in the selector to make the flow unique
+        Criterion innerSelectorMeta = Criteria.matchMetadata(output.port().toLong());
+
+        if (innerVlan.toShort() == VlanId.ANY_VALUE) {
+            TrafficSelector outerSelector = buildSelector(inport, outerVlan, outerPbit, dstMac);
+            installDownstreamRulesForAnyVlan(fwd, output, outerSelector,
+                                             buildSelector(inport,
+                                                           Criteria.matchVlanId(VlanId.ANY),
+                                                           innerSelectorMeta));
+        } else {
+            // Required to differentiate the same match flows
+            // Please note that S tag and S p bit values will be same for the same service - so conflict flows!
+            // Metadata match criteria solves the conflict issue - but not used by the voltha
+            // Maybe - find a better way to solve the above problem
+            Criterion metadata = Criteria.matchMetadata(innerVlan.toShort());
+            TrafficSelector outerSelector = buildSelector(inport, metadata, outerVlan, outerPbit, dstMac);
+            installDownstreamRulesForVlans(fwd, output, outerSelector, buildSelector(inport, innerVid,
+                                                                                     innerSelectorMeta));
+        }
+    }
+
+    private void installDownstreamRulesForVlans(ForwardingObjective fwd, Instruction output,
+                                                TrafficSelector outerSelector, TrafficSelector innerSelector) {
+
+        List<Pair<Instruction, Instruction>> vlanOps =
+                vlanOps(fwd,
+                        L2ModificationInstruction.L2SubType.VLAN_POP);
+
+        if (vlanOps == null || vlanOps.isEmpty()) {
+            return;
+        }
+
+        Pair<Instruction, Instruction> popAndRewrite = vlanOps.remove(0);
+
+        TrafficTreatment innerTreatment;
+        VlanId setVlanId = ((L2ModificationInstruction.ModVlanIdInstruction) popAndRewrite.getRight()).vlanId();
+        if (VlanId.NONE.equals(setVlanId)) {
+            innerTreatment = (buildTreatment(popAndRewrite.getLeft(), fetchMeter(fwd),
+                                             writeMetadataIncludingOnlyTp(fwd), output));
+        } else {
+            innerTreatment = (buildTreatment(popAndRewrite.getRight(),
+                                             fetchMeter(fwd), writeMetadataIncludingOnlyTp(fwd), output));
+        }
+
+        List<Instruction> setVlanPcps = findL2Instructions(L2ModificationInstruction.L2SubType.VLAN_PCP,
+                                                           fwd.treatment().allInstructions());
+
+        Instruction innerPbitSet = null;
+
+        if (setVlanPcps != null && !setVlanPcps.isEmpty()) {
+            innerPbitSet = setVlanPcps.get(0);
+        }
+
+        VlanId remarkInnerVlan = null;
+        Optional<Criterion> vlanIdCriterion = readFromSelector(innerSelector, Criterion.Type.VLAN_VID);
+        if (vlanIdCriterion.isPresent()) {
+            remarkInnerVlan = ((VlanIdCriterion) vlanIdCriterion.get()).vlanId();
+        }
+
+        Instruction modVlanId = null;
+        if (innerPbitSet != null) {
+            modVlanId = Instructions.modVlanId(remarkInnerVlan);
+        }
+
+        //match: in port (nni), s-tag
+        //action: pop vlan (s-tag), write metadata, go to table 1, meter
+        FlowRule.Builder outer = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(outerSelector)
+                .withTreatment(buildTreatment(popAndRewrite.getLeft(), modVlanId,
+                                              innerPbitSet, fetchMeter(fwd),
+                                              fetchWriteMetadata(fwd),
+                                              Instructions.transition(QQ_TABLE)));
+
+        //match: in port (nni), c-tag
+        //action: immediate: write metadata and pop, meter, output
+        FlowRule.Builder inner = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .forTable(QQ_TABLE)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(innerSelector)
+                .withTreatment(innerTreatment);
+        applyRules(fwd, inner, outer);
+    }
+
+    private void installDownstreamRulesForAnyVlan(ForwardingObjective fwd, Instruction output,
+                                                  TrafficSelector outerSelector, TrafficSelector innerSelector) {
+
+        //match: in port (nni), s-tag
+        //action: immediate: write metadata, pop vlan, meter and go to table 1
+        FlowRule.Builder outer = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(outerSelector)
+                .withTreatment(buildTreatment(Instructions.popVlan(), fetchMeter(fwd),
+                                              fetchWriteMetadata(fwd), Instructions.transition(QQ_TABLE)));
+
+        //match: in port (nni) and s-tag
+        //action: immediate : write metadata, meter and output
+        FlowRule.Builder inner = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .forTable(QQ_TABLE)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(innerSelector)
+                .withTreatment(buildTreatment(fetchMeter(fwd),
+                                              writeMetadataIncludingOnlyTp(fwd), output));
+
+        applyRules(fwd, inner, outer);
+    }
+
+    private void installUpstreamRules(ForwardingObjective fwd) {
+        List<Pair<Instruction, Instruction>> vlanOps =
+                vlanOps(fwd,
+                        L2ModificationInstruction.L2SubType.VLAN_PUSH);
+
+        if (vlanOps == null || vlanOps.isEmpty()) {
+            return;
+        }
+
+        Instruction output = fetchOutput(fwd, UPSTREAM);
+
+        if (output == null) {
+            return;
+        }
+
+        Pair<Instruction, Instruction> outerPair = vlanOps.remove(0);
+
+        boolean noneValueVlanStatus = checkNoneVlanCriteria(fwd);
+        boolean anyValueVlanStatus = checkAnyVlanMatchCriteria(fwd);
+
+        if (anyValueVlanStatus) {
+            installUpstreamRulesForAnyVlan(fwd, output, outerPair);
+        } else {
+            Pair<Instruction, Instruction> innerPair = outerPair;
+            outerPair = vlanOps.remove(0);
+            installUpstreamRulesForVlans(fwd, output, innerPair, outerPair, noneValueVlanStatus);
+        }
+    }
+
+    private void installUpstreamRulesForVlans(ForwardingObjective fwd, Instruction output,
+                                              Pair<Instruction, Instruction> innerPair,
+                                              Pair<Instruction, Instruction> outerPair, Boolean noneValueVlanStatus) {
+
+        List<Instruction> setVlanPcps = findL2Instructions(L2ModificationInstruction.L2SubType.VLAN_PCP,
+                                                           fwd.treatment().allInstructions());
+
+        Instruction innerPbitSet = null;
+        Instruction outerPbitSet = null;
+
+        if (setVlanPcps != null && !setVlanPcps.isEmpty()) {
+            innerPbitSet = setVlanPcps.get(0);
+            outerPbitSet = setVlanPcps.get(1);
+        }
+
+        TrafficTreatment innerTreatment;
+        if (noneValueVlanStatus) {
+            innerTreatment = buildTreatment(innerPair.getLeft(), innerPair.getRight(), fetchMeter(fwd),
+                                            fetchWriteMetadata(fwd), innerPbitSet,
+                                            Instructions.transition(QQ_TABLE));
+        } else {
+            innerTreatment = buildTreatment(innerPair.getRight(), fetchMeter(fwd), fetchWriteMetadata(fwd),
+                                            innerPbitSet, Instructions.transition(QQ_TABLE));
+        }
+
+        //match: in port, vlanId (0 or None)
+        //action:
+        //if vlanId None, push & set c-tag go to table 1
+        //if vlanId 0 or any specific vlan, set c-tag, write metadata, meter and go to table 1
+        FlowRule.Builder inner = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(fwd.selector())
+                .withTreatment(innerTreatment);
+
+        PortCriterion inPort = (PortCriterion)
+                fwd.selector().getCriterion(Criterion.Type.IN_PORT);
+
+        VlanId cVlanId = ((L2ModificationInstruction.ModVlanIdInstruction)
+                innerPair.getRight()).vlanId();
+
+        //match: in port, c-tag
+        //action: immediate: push s-tag, write metadata, meter and output
+        FlowRule.Builder outer = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .forTable(QQ_TABLE)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withTreatment(buildTreatment(outerPair.getLeft(), outerPair.getRight(),
+                                              fetchMeter(fwd), writeMetadataIncludingOnlyTp(fwd),
+                                              outerPbitSet, output));
+
+        if (innerPbitSet != null) {
+            byte innerPbit = ((L2ModificationInstruction.ModVlanPcpInstruction)
+                    innerPbitSet).vlanPcp();
+            outer.withSelector(buildSelector(inPort, Criteria.matchVlanId(cVlanId), Criteria.matchVlanPcp(innerPbit)));
+        } else {
+            outer.withSelector(buildSelector(inPort, Criteria.matchVlanId(cVlanId)));
+        }
+
+        applyRules(fwd, inner, outer);
+    }
+
+    private void installUpstreamRulesForAnyVlan(ForwardingObjective fwd, Instruction output,
+                                                Pair<Instruction, Instruction> outerPair) {
+
+        log.debug("Installing upstream rules for any value vlan");
+
+        //match: in port and any-vlan (coming from OLT app.)
+        //action: write metadata, go to table 1 and meter
+        FlowRule.Builder inner = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(fwd.selector())
+                .withTreatment(buildTreatment(Instructions.transition(QQ_TABLE), fetchMeter(fwd),
+                                              fetchWriteMetadata(fwd)));
+
+        //match: in port and any-vlan (coming from OLT app.)
+        //action: immediate: push:QinQ, vlanId (s-tag), write metadata, meter and output
+        FlowRule.Builder outer = DefaultFlowRule.builder()
+                .fromApp(fwd.appId())
+                .forDevice(deviceId)
+                .forTable(QQ_TABLE)
+                .makePermanent()
+                .withPriority(fwd.priority())
+                .withSelector(fwd.selector())
+                .withTreatment(buildTreatment(outerPair.getLeft(), outerPair.getRight(),
+                                              fetchMeter(fwd), writeMetadataIncludingOnlyTp(fwd), output));
+
+        applyRules(fwd, inner, outer);
+    }
+
+    private boolean checkNoneVlanCriteria(ForwardingObjective fwd) {
+        // Add the VLAN_PUSH treatment if we're matching on VlanId.NONE
+        Criterion vlanMatchCriterion = filterForCriterion(fwd.selector().criteria(), Criterion.Type.VLAN_VID);
+        boolean noneValueVlanStatus = false;
+        if (vlanMatchCriterion != null) {
+            noneValueVlanStatus = ((VlanIdCriterion) vlanMatchCriterion).vlanId().equals(VlanId.NONE);
+        }
+        return noneValueVlanStatus;
+    }
+
+    private boolean checkAnyVlanMatchCriteria(ForwardingObjective fwd) {
+        Criterion anyValueVlanCriterion = fwd.selector().criteria().stream()
+                .filter(c -> c.type().equals(Criterion.Type.VLAN_VID))
+                .filter(vc -> ((VlanIdCriterion) vc).vlanId().toShort() == VlanId.ANY_VALUE)
+                .findAny().orElse(null);
+
+        if (anyValueVlanCriterion == null) {
+            log.debug("Any value vlan match criteria is not found, criteria {}",
+                      fwd.selector().criteria());
+            return false;
+        }
+
+        return true;
+    }
+
+    private Instruction fetchOutput(ForwardingObjective fwd, String direction) {
+        Instruction output = fwd.treatment().allInstructions().stream()
+                .filter(i -> i.type() == Instruction.Type.OUTPUT)
+                .findFirst().orElse(null);
+
+        if (output == null) {
+            log.error("OLT {} rule has no output", direction);
+            fail(fwd, ObjectiveError.BADPARAMS);
+            return null;
+        }
+        return output;
+    }
+
+    private Instruction fetchMeter(ForwardingObjective fwd) {
+        Instruction meter = fwd.treatment().metered();
+
+        if (meter == null) {
+            log.debug("Meter instruction is not found for the forwarding objective {}", fwd);
+            return null;
+        }
+
+        log.debug("Meter instruction is found.");
+        return meter;
+    }
+
+    private Instructions.MetadataInstruction fetchWriteMetadata(ForwardingObjective fwd) {
+        Instructions.MetadataInstruction writeMetadata = fwd.treatment().writeMetadata();
+
+        if (writeMetadata == null) {
+            log.warn("Write metadata is not found for the forwarding obj");
+            fail(fwd, ObjectiveError.BADPARAMS);
+            return null;
+        }
+
+        log.debug("Write metadata is found {}", writeMetadata);
+        return writeMetadata;
+    }
+
+    private List<Pair<Instruction, Instruction>> vlanOps(ForwardingObjective fwd,
+                                                         L2ModificationInstruction.L2SubType type) {
+
+        List<Pair<Instruction, Instruction>> vlanOps = findVlanOps(
+                fwd.treatment().allInstructions(), type);
+
+        if (vlanOps == null || vlanOps.isEmpty()) {
+            String direction = type == L2ModificationInstruction.L2SubType.VLAN_POP
+                    ? DOWNSTREAM : UPSTREAM;
+            log.error("Missing vlan operations in {} forwarding: {}", direction, fwd);
+            fail(fwd, ObjectiveError.BADPARAMS);
+            return ImmutableList.of();
+        }
+        return vlanOps;
+    }
+
+
+    private List<Pair<Instruction, Instruction>> findVlanOps(List<Instruction> instructions,
+                                                             L2ModificationInstruction.L2SubType type) {
+
+        List<Instruction> vlanOperations = findL2Instructions(
+                type,
+                instructions);
+        List<Instruction> vlanSets = findL2Instructions(
+                L2ModificationInstruction.L2SubType.VLAN_ID,
+                instructions);
+
+        if (vlanOperations.size() != vlanSets.size()) {
+            return ImmutableList.of();
+        }
+
+        List<Pair<Instruction, Instruction>> pairs = Lists.newArrayList();
+
+        for (int i = 0; i < vlanOperations.size(); i++) {
+            pairs.add(new ImmutablePair<>(vlanOperations.get(i), vlanSets.get(i)));
+        }
+        return pairs;
+    }
+
+    private List<Instruction> findL2Instructions(L2ModificationInstruction.L2SubType subType,
+                                                 List<Instruction> actions) {
+        return actions.stream()
+                .filter(i -> i.type() == Instruction.Type.L2MODIFICATION)
+                .filter(i -> ((L2ModificationInstruction) i).subtype() == subType)
+                .collect(Collectors.toList());
+    }
+
+    private void provisionEthTypeBasedFilter(FilteringObjective filter,
+                                             EthTypeCriterion ethType,
+                                             Instructions.OutputInstruction output,
+                                             L2ModificationInstruction vlanId,
+                                             L2ModificationInstruction vlanPush) {
+
+        Instruction meter = filter.meta().metered();
+        Instruction writeMetadata = filter.meta().writeMetadata();
+
+        TrafficSelector selector = buildSelector(filter.key(), ethType);
+        TrafficTreatment treatment;
+
+        if (vlanPush == null || vlanId == null) {
+            treatment = buildTreatment(output, meter, writeMetadata);
+        } else {
+            // we need to push the vlan because it came untagged (ATT)
+            treatment = buildTreatment(output, meter, vlanPush, vlanId, writeMetadata);
+        }
+
+        buildAndApplyRule(filter, selector, treatment);
+
+    }
+
+    private void provisionIgmp(FilteringObjective filter, EthTypeCriterion ethType,
+                               IPProtocolCriterion ipProto,
+                               Instructions.OutputInstruction output,
+                               Instruction vlan, Instruction pcp) {
+
+        Instruction meter = filter.meta().metered();
+        Instruction writeMetadata = filter.meta().writeMetadata();
+
+        // uniTagMatch
+        VlanIdCriterion vlanId = (VlanIdCriterion) filterForCriterion(filter.conditions(),
+                                                                      Criterion.Type.VLAN_VID);
+
+        TrafficSelector selector = buildSelector(filter.key(), ethType, ipProto, vlanId);
+        TrafficTreatment treatment = buildTreatment(output, vlan, pcp, meter, writeMetadata);
+        buildAndApplyRule(filter, selector, treatment);
+    }
+
+    private void provisionDhcp(FilteringObjective filter, EthTypeCriterion ethType,
+                               IPProtocolCriterion ipProto,
+                               UdpPortCriterion udpSrcPort,
+                               UdpPortCriterion udpDstPort,
+                               Instruction vlanIdInstruction,
+                               Instruction vlanPcpInstruction,
+                               Instructions.OutputInstruction output) {
+
+        Instruction meter = filter.meta().metered();
+        Instruction writeMetadata = filter.meta().writeMetadata();
+
+        VlanIdCriterion matchVlanId = (VlanIdCriterion)
+                filterForCriterion(filter.conditions(), Criterion.Type.VLAN_VID);
+
+        TrafficSelector selector;
+        TrafficTreatment treatment;
+
+        if (matchVlanId != null) {
+            log.debug("Building selector with match VLAN, {}", matchVlanId);
+            // in case of TT upstream the packet comes tagged and the vlan is swapped.
+            selector = buildSelector(filter.key(), ethType, ipProto, udpSrcPort,
+                                     udpDstPort, matchVlanId);
+            treatment = buildTreatment(output, meter, writeMetadata,
+                                       vlanIdInstruction, vlanPcpInstruction);
+        } else {
+            log.debug("Building selector with no VLAN");
+            // in case of ATT upstream the packet comes in untagged and we need to push the vlan
+            selector = buildSelector(filter.key(), ethType, ipProto, udpSrcPort, udpDstPort);
+            treatment = buildTreatment(output, meter, vlanIdInstruction, writeMetadata);
+        }
+        //In case of downstream there will be no match on the VLAN, which is null,
+        // so it will just be output, meter, writeMetadata
+
+        buildAndApplyRule(filter, selector, treatment);
+    }
+
+    private void provisionPPPoED(FilteringObjective filter, EthTypeCriterion ethType,
+                                 Instruction vlanIdInstruction,
+                                 Instruction vlanPcpInstruction,
+                                 Instructions.OutputInstruction output) {
+        Instruction meter = filter.meta().metered();
+        Instruction writeMetadata = filter.meta().writeMetadata();
+
+        VlanIdCriterion matchVlanId = (VlanIdCriterion)
+                filterForCriterion(filter.conditions(), Criterion.Type.VLAN_VID);
+
+        TrafficSelector selector;
+        TrafficTreatment treatment;
+
+        if (matchVlanId != null) {
+            log.debug("Building pppoed selector with match VLAN {}.", matchVlanId);
+        } else {
+            log.debug("Building pppoed selector without match VLAN.");
+        }
+
+        selector = buildSelector(filter.key(), ethType, matchVlanId);
+        treatment = buildTreatment(output, meter, writeMetadata, vlanIdInstruction, vlanPcpInstruction);
+        buildAndApplyRule(filter, selector, treatment);
+    }
+
+    private void buildAndApplyRule(FilteringObjective filter, TrafficSelector selector,
+                                   TrafficTreatment treatment) {
+        FlowRule rule = DefaultFlowRule.builder()
+                .fromApp(filter.appId())
+                .forDevice(deviceId)
+                .forTable(0)
+                .makePermanent()
+                .withSelector(selector)
+                .withTreatment(treatment)
+                .withPriority(filter.priority())
+                .build();
+
+        if (accumulator != null) {
+            if (log.isDebugEnabled()) {
+                log.debug("Adding pair to batch: {}", Pair.of(filter, rule));
+            }
+            accumulator.add(Pair.of(filter, rule));
+        } else {
+            FlowRuleOperations.Builder opsBuilder = FlowRuleOperations.builder();
+            switch (filter.type()) {
+                case PERMIT:
+                    opsBuilder.add(rule);
+                    break;
+                case DENY:
+                    opsBuilder.remove(rule);
+                    break;
+                default:
+                    log.warn("Unknown filter type : {}", filter.type());
+                    fail(filter, ObjectiveError.UNSUPPORTED);
+            }
+            applyFlowRules(ImmutableList.of(filter), opsBuilder);
+        }
+    }
+
+    private void applyRules(ForwardingObjective fwd, FlowRule.Builder... fwdBuilders) {
+        FlowRuleOperations.Builder builder = FlowRuleOperations.builder();
+        switch (fwd.op()) {
+            case ADD:
+                for (FlowRule.Builder fwdBuilder : fwdBuilders) {
+                    builder.add(fwdBuilder.build());
+                }
+                break;
+            case REMOVE:
+                for (FlowRule.Builder fwdBuilder : fwdBuilders) {
+                    builder.remove(fwdBuilder.build());
+                }
+                break;
+            case ADD_TO_EXISTING:
+                break;
+            case REMOVE_FROM_EXISTING:
+                break;
+            default:
+                log.warn("Unknown forwarding operation: {}", fwd.op());
+        }
+
+        applyFlowRules(ImmutableList.of(fwd), builder);
+
+
+    }
+
+    private void applyFlowRules(List<Objective> objectives, FlowRuleOperations.Builder builder) {
+        flowRuleService.apply(builder.build(new FlowRuleOperationsContext() {
+            @Override
+            public void onSuccess(FlowRuleOperations ops) {
+                objectives.forEach(obj -> {
+                    pass(obj);
+                });
+            }
+
+            @Override
+            public void onError(FlowRuleOperations ops) {
+                objectives.forEach(obj -> {
+                    fail(obj, ObjectiveError.FLOWINSTALLATIONFAILED);
+                });
+
+            }
+        }));
+    }
+
+    // Builds the batch using the accumulated flow rules
+    private void sendFilters(List<Pair<FilteringObjective, FlowRule>> pairs) {
+        FlowRuleOperations.Builder flowOpsBuilder = FlowRuleOperations.builder();
+        log.debug("Sending batch of {} filter-objs", pairs.size());
+        List<Objective> filterObjs = Lists.newArrayList();
+        // Iterates over all accumulated flow rules and then build an unique batch
+        pairs.forEach(pair -> {
+            FilteringObjective filter = pair.getLeft();
+            FlowRule rule = pair.getRight();
+            switch (filter.type()) {
+                case PERMIT:
+                    flowOpsBuilder.add(rule);
+                    log.debug("Applying add filter-obj {} to device: {}", filter.id(), deviceId);
+                    filterObjs.add(filter);
+                    break;
+                case DENY:
+                    flowOpsBuilder.remove(rule);
+                    log.debug("Deleting flow rule {} to device: {}", rule, deviceId);
+                    filterObjs.add(filter);
+                    break;
+                default:
+                    fail(filter, ObjectiveError.UNKNOWN);
+                    log.warn("Unknown forwarding type {}", filter.type());
+            }
+        });
+        if (log.isDebugEnabled()) {
+            log.debug("Applying batch {}", flowOpsBuilder.build());
+        }
+        // Finally applies the operations
+        applyFlowRules(filterObjs, flowOpsBuilder);
+    }
+
+    private Criterion filterForCriterion(Collection<Criterion> criteria, Criterion.Type type) {
+        return criteria.stream()
+                .filter(c -> c.type().equals(type))
+                .limit(1)
+                .findFirst().orElse(null);
+    }
+
+    private TrafficSelector buildSelector(Criterion... criteria) {
+
+        TrafficSelector.Builder sBuilder = DefaultTrafficSelector.builder();
+
+        Arrays.stream(criteria).filter(Objects::nonNull).forEach(sBuilder::add);
+
+        return sBuilder.build();
+    }
+
+    private TrafficTreatment buildTreatment(Instruction... instructions) {
+
+        TrafficTreatment.Builder tBuilder = DefaultTrafficTreatment.builder();
+
+        Arrays.stream(instructions).filter(Objects::nonNull).forEach(tBuilder::add);
+
+        return tBuilder.build();
+    }
+
+    private Instruction writeMetadataIncludingOnlyTp(ForwardingObjective fwd) {
+
+        return Instructions.writeMetadata(
+                fetchWriteMetadata(fwd).metadata() & 0xFFFF00000000L, 0L);
+    }
+
+    private void fail(Objective obj, ObjectiveError error) {
+        obj.context().ifPresent(context -> context.onError(obj, error));
+    }
+
+    private void pass(Objective obj) {
+        obj.context().ifPresent(context -> context.onSuccess(obj));
+    }
+
+
+    private class InnerGroupListener implements GroupListener {
+        @Override
+        public void event(GroupEvent event) {
+            GroupKey key = event.subject().appCookie();
+            NextObjective obj = pendingGroups.getIfPresent(key);
+            if (obj == null) {
+                log.debug("No pending group for {}, moving on", key);
+                return;
+            }
+            log.trace("Event {} for group {}, handling pending" +
+                              "NextGroup {}", event.type(), key, obj.id());
+            if (event.type() == GroupEvent.Type.GROUP_ADDED ||
+                    event.type() == GroupEvent.Type.GROUP_UPDATED) {
+                flowObjectiveStore.putNextGroup(obj.id(), new OltPipelineGroup(key));
+                pass(obj);
+                pendingGroups.invalidate(key);
+            } else if (event.type() == GroupEvent.Type.GROUP_REMOVED) {
+                flowObjectiveStore.removeNextGroup(obj.id());
+                pass(obj);
+                pendingGroups.invalidate(key);
+            }
+        }
+    }
+
+    private static class OltPipelineGroup implements NextGroup {
+
+        private final GroupKey key;
+
+        public OltPipelineGroup(GroupKey key) {
+            this.key = key;
+        }
+
+        public GroupKey key() {
+            return key;
+        }
+
+        @Override
+        public byte[] data() {
+            return appKryo.serialize(key);
+        }
+
+    }
+
+    @Override
+    public List<String> getNextMappings(NextGroup nextGroup) {
+        // TODO Implementation deferred to vendor
+        return null;
+    }
+
+    // Flow rules accumulator for reducing the number of transactions required to the devices.
+    private final class ObjectiveAccumulator
+            extends AbstractAccumulator<Pair<FilteringObjective, FlowRule>> {
+
+        ObjectiveAccumulator(int maxFilter, int maxBatchMS, int maxIdleMS) {
+            super(TIMER, maxFilter, maxBatchMS, maxIdleMS);
+        }
+
+        @Override
+        public void processItems(List<Pair<FilteringObjective, FlowRule>> pairs) {
+            // Triggers creation of a batch using the list of flowrules generated from objs.
+            accumulatorExecutorService.execute(new FlowRulesBuilderTask(pairs));
+        }
+    }
+
+    // Task for building batch of flow rules in a separate thread.
+    private final class FlowRulesBuilderTask implements Runnable {
+        private final List<Pair<FilteringObjective, FlowRule>> pairs;
+
+        FlowRulesBuilderTask(List<Pair<FilteringObjective, FlowRule>> pairs) {
+            this.pairs = pairs;
+        }
+
+        @Override
+        public void run() {
+            try {
+                sendFilters(pairs);
+            } catch (Exception e) {
+                log.warn("Unable to send objectives", e);
+            }
+        }
+    }
+}
\ No newline at end of file