InstructionInfo redesign
[genius.git] / itm / itm-impl / src / main / java / org / opendaylight / genius / itm / impl / ItmUtils.java
index 4c342b2e383638ca97641f32e9a5c65de36cb250..41b0de91def73526d41bee2b47172beaf1374f2c 100644 (file)
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2016 Ericsson India Global Services Pvt Ltd. and others.  All rights reserved.
+ * Copyright © 2016, 2017 Ericsson India Global Services Pvt Ltd. and others.  All rights reserved.
  *
  * This program and the accompanying materials are made available under the
  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
@@ -13,6 +13,15 @@ import com.google.common.net.InetAddresses;
 import com.google.common.util.concurrent.CheckedFuture;
 import com.google.common.util.concurrent.FutureCallback;
 import com.google.common.util.concurrent.Futures;
+import java.math.BigInteger;
+import java.net.InetAddress;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.List;
+import java.util.UUID;
+import java.util.concurrent.ExecutionException;
+import java.util.concurrent.Future;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.net.util.SubnetUtils;
 import org.apache.commons.net.util.SubnetUtils.SubnetInfo;
@@ -24,29 +33,49 @@ import org.opendaylight.controller.md.sal.common.api.data.TransactionCommitFaile
 import org.opendaylight.genius.itm.api.IITMProvider;
 import org.opendaylight.genius.itm.confighelpers.HwVtep;
 import org.opendaylight.genius.itm.globals.ITMConstants;
-import org.opendaylight.genius.mdsalutil.*;
+import org.opendaylight.genius.mdsalutil.ActionInfo;
+import org.opendaylight.genius.mdsalutil.FlowEntity;
+import org.opendaylight.genius.mdsalutil.InstructionInfo;
+import org.opendaylight.genius.mdsalutil.MDSALUtil;
+import org.opendaylight.genius.mdsalutil.MatchFieldType;
+import org.opendaylight.genius.mdsalutil.MatchInfo;
+import org.opendaylight.genius.mdsalutil.NwConstants;
+import org.opendaylight.genius.mdsalutil.actions.ActionPuntToController;
+import org.opendaylight.genius.mdsalutil.instructions.InstructionApplyActions;
 import org.opendaylight.genius.mdsalutil.interfaces.IMdsalApiManager;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.iana._if.type.rev140508.Tunnel;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpAddress;
-import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev100924.IpPrefix;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpAddress;
+import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev130715.IpPrefix;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.InterfaceType;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.Interfaces;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.InterfacesState;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.Interface;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.InterfaceBuilder;
 import org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.InterfaceKey;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.TunnelMonitorParams;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.tunnels_state.StateTunnelListKey;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.DcGatewayIpList;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.dc.gateway.ip.list.DcGatewayIp;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.l2.types.rev130827.VlanId;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.*;
-import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.*;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.AllocateIdInput;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.AllocateIdInputBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.AllocateIdOutput;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.IdManagerService;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.ReleaseIdInput;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.idmanager.rev160406.ReleaseIdInputBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.IfL2vlan;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.IfL2vlanBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.IfTunnel;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.IfTunnelBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.ParentRefs;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.ParentRefsBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.TunnelMonitoringTypeBase;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.TunnelTypeBase;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.TunnelTypeGre;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.TunnelTypeMplsOverGre;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.TunnelTypeVxlan;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.interfaces._interface.NodeIdentifier;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.interfaces._interface.NodeIdentifierBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.interfaces._interface.NodeIdentifierKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.TunnelMonitorInterval;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.TunnelMonitorIntervalBuilder;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.TunnelMonitorParams;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.TunnelMonitorParamsBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.VtepConfigSchemas;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.VtepIpPools;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.config.rev160406.vtep.config.schemas.VtepConfigSchema;
@@ -67,48 +96,49 @@ import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.dpn.teps.info.TunnelEndPoints;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.dpn.teps.info.TunnelEndPointsBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.dpn.teps.info.TunnelEndPointsKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.dpn.teps.info.tunnel.end.points.TzMembership;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.dpn.endpoints.dpn.teps.info.tunnel.end.points.TzMembershipBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.external.tunnel.list.ExternalTunnel;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.external.tunnel.list.ExternalTunnelBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.external.tunnel.list.ExternalTunnelKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.tunnel.list.InternalTunnel;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.tunnel.list.InternalTunnelBuilder;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.tunnel.list.InternalTunnelKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.op.rev160406.tunnels_state.StateTunnelListKey;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.DcGatewayIpList;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.TransportZones;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.dc.gateway.ip.list.DcGatewayIp;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.transport.zones.TransportZone;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.transport.zones.TransportZoneKey;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.transport.zones.transport.zone.Subnets;
 import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.itm.rev160406.transport.zones.transport.zone.subnets.Vteps;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.genius.interfacemanager.rev160406.TunnelMonitoringTypeBfd;
+import org.opendaylight.yang.gen.v1.urn.opendaylight.l2.types.rev130827.VlanId;
 import org.opendaylight.yangtools.yang.binding.DataObject;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier;
 import org.opendaylight.yangtools.yang.binding.InstanceIdentifier.InstanceIdentifierBuilder;
 import org.opendaylight.yangtools.yang.common.RpcResult;
+import org.opendaylight.genius.utils.cache.DataStoreCache;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
-import java.math.BigInteger;
-import java.net.InetAddress;
-import java.util.ArrayList;
-import java.util.Collection;
-import java.util.Collections;
-import java.util.List;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.Future;
-
 public class ItmUtils {
 
     public static final String DUMMY_IP_ADDRESS = "0.0.0.0";
     public static final String TUNNEL_TYPE_VXLAN = "VXLAN";
     public static final String TUNNEL_TYPE_GRE = "GRE";
-    public static final String TUNNEL = "TUNNEL";
+    public static final String TUNNEL = "tun";
     public static ItmCache itmCache = new ItmCache();
 
     private static final Logger LOG = LoggerFactory.getLogger(ItmUtils.class);
 
     public static final FutureCallback<Void> DEFAULT_CALLBACK = new FutureCallback<Void>() {
+        @Override
         public void onSuccess(Void result) {
             LOG.debug("Success in Datastore write operation");
         }
 
+        @Override
         public void onFailure(Throwable error) {
             LOG.error("Error in Datastore write operation", error);
         }
@@ -116,17 +146,11 @@ public class ItmUtils {
 
     public static <T extends DataObject> Optional<T> read(LogicalDatastoreType datastoreType,
                                                           InstanceIdentifier<T> path, DataBroker broker) {
-
-        ReadOnlyTransaction tx = broker.newReadOnlyTransaction();
-
-        Optional<T> result = Optional.absent();
-        try {
-            result = tx.read(datastoreType, path).get();
+        try (ReadOnlyTransaction tx = broker.newReadOnlyTransaction()) {
+            return tx.read(datastoreType, path).get();
         } catch (Exception e) {
             throw new RuntimeException(e);
         }
-
-        return result;
     }
 
     public static <T extends DataObject> void asyncWrite(LogicalDatastoreType datastoreType,
@@ -181,7 +205,7 @@ public class ItmUtils {
         String trunkInterfaceName = String.format(  "%s:%s:%s:%s", parentInterfaceName, localHostName,
                 remoteHostName, tunnelTypeStr);
         LOG.trace("trunk interface name is {}", trunkInterfaceName);
-        trunkInterfaceName = String.format("%s:%s", TUNNEL, getUniqueId(idManager, trunkInterfaceName));
+        trunkInterfaceName = String.format("%s%s", TUNNEL, getUniqueIdString(trunkInterfaceName));
         return trunkInterfaceName;
     }
 
@@ -194,7 +218,7 @@ public class ItmUtils {
         }
         String trunkInterfaceName = String.format("%s:%s:%s:%s", parentInterfaceName, localHostName, remoteHostName, tunnelTypeStr);
         LOG.trace("Releasing Id for trunkInterface - {}", trunkInterfaceName );
-        releaseId(idManager, trunkInterfaceName) ;
+        //releaseId(idManager, trunkInterfaceName) ;
     }
 
     public static InetAddress getInetAddressFromIpAddress(IpAddress ip) {
@@ -214,12 +238,15 @@ public class ItmUtils {
         return new DPNTEPsInfoBuilder().setKey(new DPNTEPsInfoKey(dpId)).setTunnelEndPoints(endpoints).build();
     }
 
-    public static TunnelEndPoints createTunnelEndPoints(BigInteger dpnId, IpAddress ipAddress, String portName, int vlanId,
-                                                        IpPrefix prefix, IpAddress gwAddress, String zoneName, Class<? extends TunnelTypeBase>  tunnel_type) {
+    public static TunnelEndPoints createTunnelEndPoints(BigInteger dpnId, IpAddress ipAddress, String portName,
+                                                        boolean isOfTunnel, int vlanId, IpPrefix prefix,
+                                                        IpAddress gwAddress, List<TzMembership> zones,
+                                                        Class<? extends TunnelTypeBase>  tunnel_type) {
         // when Interface Mgr provides support to take in Dpn Id
         return new TunnelEndPointsBuilder().setKey(new TunnelEndPointsKey(ipAddress, portName,tunnel_type, vlanId))
-                .setSubnetMask(prefix).setGwIpAddress(gwAddress).setTransportZone(zoneName)
-                .setInterfaceName(ItmUtils.getInterfaceName(dpnId, portName, vlanId)).setTunnelType(tunnel_type).build();
+                .setSubnetMask(prefix).setGwIpAddress(gwAddress).setTzMembership(zones)
+                .setOptionOfTunnel(isOfTunnel).setInterfaceName(ItmUtils.getInterfaceName(dpnId, portName, vlanId))
+                .setTunnelType(tunnel_type).build();
     }
 
     public static DpnEndpoints createDpnEndpoints(List<DPNTEPsInfo> dpnTepInfo) {
@@ -233,36 +260,33 @@ public class ItmUtils {
         return id;
     }
 
-    public static Interface buildTunnelInterface(BigInteger dpn, String ifName, String desc, boolean enabled, Class<? extends TunnelTypeBase> tunType,
-                                                 IpAddress localIp, IpAddress remoteIp, IpAddress gatewayIp,Integer vlanId, boolean internal, Boolean monitorEnabled, Class<? extends TunnelMonitoringTypeBase> monitorProtocol, Integer monitorInterval) {
+    public static Interface buildTunnelInterface(BigInteger dpn, String ifName, String desc, boolean enabled,
+                                                 Class<? extends TunnelTypeBase> tunType, IpAddress localIp,
+                                                 IpAddress remoteIp, IpAddress gatewayIp, Integer vlanId,
+                                                 boolean internal, Boolean monitorEnabled,
+                                                 Class<? extends TunnelMonitoringTypeBase> monitorProtocol,
+                                                 Integer monitorInterval, boolean useOfTunnel) {
         InterfaceBuilder builder = new InterfaceBuilder().setKey(new InterfaceKey(ifName)).setName(ifName)
                 .setDescription(desc).setEnabled(enabled).setType(Tunnel.class);
         ParentRefs parentRefs = new ParentRefsBuilder().setDatapathNodeIdentifier(dpn).build();
         builder.addAugmentation(ParentRefs.class, parentRefs);
+        Long monitoringInterval=null;
         if( vlanId > 0) {
             IfL2vlan l2vlan = new IfL2vlanBuilder().setVlanId(new VlanId(vlanId)).build();
             builder.addAugmentation(IfL2vlan.class, l2vlan);
         }
         LOG.debug("buildTunnelInterface: monitorProtocol = {} and monitorInterval = {}",monitorProtocol.getName(),monitorInterval);
 
-        Long monitoringInterval = (long)ITMConstants.BFD_DEFAULT_MONITOR_INTERVAL;
-        Boolean monitoringEnabled = true;
-        if(monitorInterval!= null)
+
+        if(monitorInterval != null) {
             monitoringInterval = monitorInterval.longValue();
-        else {
-            if (monitorProtocol.getName().contains("Bfd"))
-                monitoringInterval = (long) ITMConstants.BFD_DEFAULT_MONITOR_INTERVAL;
-            else
-                monitoringInterval = (long) ITMConstants.DEFAULT_MONITOR_INTERVAL;
         }
-        LOG.debug("buildTunnelInterface: monitorProtocol = {} and monitorInterval = {}",monitorProtocol.getName(),monitorInterval);
 
-        if(monitorEnabled!=null  )
-            monitoringEnabled = monitorEnabled;
-        IfTunnel tunnel = new IfTunnelBuilder().setTunnelDestination(remoteIp).setTunnelGateway(
-                gatewayIp).setTunnelSource(localIp)
-                .setTunnelInterfaceType(tunType).setInternal(internal).setMonitorEnabled(
-                        monitoringEnabled).setMonitorProtocol(monitorProtocol).setMonitorInterval(monitoringInterval).build();
+        IfTunnel tunnel = new IfTunnelBuilder().setTunnelDestination(remoteIp).setTunnelGateway(gatewayIp)
+                .setTunnelSource(localIp).setTunnelInterfaceType(tunType).setInternal(internal)
+                .setMonitorEnabled(monitorEnabled).setMonitorProtocol(monitorProtocol)
+                .setMonitorInterval(monitoringInterval).setTunnelRemoteIpFlow(useOfTunnel)
+                .build();
         builder.addAugmentation(IfTunnel.class, tunnel);
         return builder.build();
     }
@@ -273,7 +297,7 @@ public class ItmUtils {
         InterfaceBuilder builder = new InterfaceBuilder().setKey(new InterfaceKey(tunnelIfName)).setName(
                 tunnelIfName).setDescription(desc).
                 setEnabled(enabled).setType(Tunnel.class);
-        List<NodeIdentifier> nodeIds = new ArrayList<NodeIdentifier>();
+        List<NodeIdentifier> nodeIds = new ArrayList<>();
         NodeIdentifier hWnode = new NodeIdentifierBuilder().setKey(new NodeIdentifierKey(topo_id)).setTopologyId(
                 topo_id).
                 setNodeId(node_id).build();
@@ -283,12 +307,15 @@ public class ItmUtils {
         Long monitoringInterval = (long) ITMConstants.DEFAULT_MONITOR_INTERVAL;
         Boolean monitoringEnabled = true;
         Class<? extends TunnelMonitoringTypeBase> monitoringProtocol = ITMConstants.DEFAULT_MONITOR_PROTOCOL;
-        if(monitor_interval!= null)
+        if(monitor_interval!= null) {
             monitoringInterval = monitor_interval.longValue();
-        if(monitor_enabled!=null  )
+        }
+        if(monitor_enabled!=null  ) {
             monitoringEnabled = monitor_enabled;
-        if(monitorProtocol!=null)
+        }
+        if(monitorProtocol!=null) {
             monitoringProtocol = monitorProtocol;
+        }
         IfTunnel tunnel = new IfTunnelBuilder().setTunnelDestination(destIp).setTunnelGateway(gWIp).setTunnelSource(
                 srcIp).setMonitorEnabled(monitoringEnabled).setMonitorProtocol(monitorProtocol).setMonitorInterval(100L).
                 setTunnelInterfaceType(tunType).setInternal(false).build();
@@ -321,6 +348,12 @@ public class ItmUtils {
     public static List<DPNTEPsInfo> getTunnelMeshInfo(DataBroker dataBroker) {
         List<DPNTEPsInfo> dpnTEPs= null ;
 
+        // Read the Mesh Information from Cache if not read from the DS
+        dpnTEPs = getTunnelMeshInfo() ;
+        if( dpnTEPs != null ) {
+            return dpnTEPs ;
+        }
+
         // Read the EndPoint Info from the operational database
         InstanceIdentifierBuilder<DpnEndpoints> depBuilder = InstanceIdentifier.builder( DpnEndpoints.class);
         InstanceIdentifier<DpnEndpoints> deps = depBuilder.build();
@@ -329,11 +362,27 @@ public class ItmUtils {
             DpnEndpoints tn= dpnEps.get() ;
             dpnTEPs = tn.getDPNTEPsInfo();
             LOG.debug( "Read from CONFIGURATION datastore - No. of Dpns " , dpnTEPs.size() );
-        }else
+        } else {
             LOG.debug( "No Dpn information in CONFIGURATION datastore "  );
+        }
         return dpnTEPs ;
     }
 
+    // Reading the Mesh Information from Cache
+    public static List<DPNTEPsInfo> getTunnelMeshInfo(){
+        List<DPNTEPsInfo> dpnTepsInfo = null ;
+        List<Object> values = null ;
+
+        values = DataStoreCache.getValues(ITMConstants.DPN_TEPs_Info_CACHE_NAME);
+        if( values != null ) {
+            dpnTepsInfo = new ArrayList<>() ;
+            for( Object value : values ) {
+                dpnTepsInfo.add((DPNTEPsInfo)value) ;
+            }
+        }
+        return dpnTepsInfo ;
+    }
+
     public static int getUniqueId(IdManagerService idManager, String idKey) {
         AllocateIdInput getIdInput = new AllocateIdInputBuilder()
                 .setPoolName(ITMConstants.ITM_IDPOOL_NAME)
@@ -353,6 +402,10 @@ public class ItmUtils {
         return 0;
     }
 
+    public static String getUniqueIdString(String idKey) {
+        return UUID.nameUUIDFromBytes(idKey.getBytes()).toString().substring(0, 12).replace("-", "");
+    }
+
     public static void releaseId(IdManagerService idManager, String idKey) {
         ReleaseIdInput idInput =
                 new ReleaseIdInputBuilder().setPoolName(ITMConstants.ITM_IDPOOL_NAME).setIdKey(idKey).build();
@@ -369,12 +422,13 @@ public class ItmUtils {
 
     public static List<DPNTEPsInfo> getDPNTEPListFromDPNId(DataBroker dataBroker, List<BigInteger> dpnIds) {
         List<DPNTEPsInfo> meshedDpnList = getTunnelMeshInfo(dataBroker) ;
-        List<DPNTEPsInfo> cfgDpnList = new ArrayList<DPNTEPsInfo>();
+        List<DPNTEPsInfo> cfgDpnList = new ArrayList<>();
         if( null != meshedDpnList) {
             for(BigInteger dpnId : dpnIds) {
                 for( DPNTEPsInfo teps : meshedDpnList ) {
-                    if( dpnId.equals(teps.getDPNID()))
+                    if( dpnId.equals(teps.getDPNID())) {
                         cfgDpnList.add( teps) ;
+                    }
                 }
             }
         }
@@ -382,22 +436,19 @@ public class ItmUtils {
     }
 
     public static void setUpOrRemoveTerminatingServiceTable(BigInteger dpnId, IMdsalApiManager mdsalManager, boolean addFlag) {
-        String logmsg = ( addFlag == true) ? "Installing" : "Removing";
+        String logmsg = addFlag ? "Installing" : "Removing";
         LOG.trace( logmsg + " PUNT to Controller flow in DPN {} ", dpnId );
-        long dpId;
-        List<ActionInfo> listActionInfo = new ArrayList<ActionInfo>();
-        listActionInfo.add(new ActionInfo(ActionType.punt_to_controller,
-                new String[] {}));
+        List<ActionInfo> listActionInfo = new ArrayList<>();
+        listActionInfo.add(new ActionPuntToController());
 
         try {
-            List<MatchInfo> mkMatches = new ArrayList<MatchInfo>();
+            List<MatchInfo> mkMatches = new ArrayList<>();
 
             mkMatches.add(new MatchInfo(MatchFieldType.tunnel_id, new BigInteger[] {
                     BigInteger.valueOf(ITMConstants.LLDP_SERVICE_ID) }));
 
-            List<InstructionInfo> mkInstructions = new ArrayList<InstructionInfo>();
-            mkInstructions.add(new InstructionInfo(InstructionType.apply_actions,
-                    listActionInfo));
+            List<InstructionInfo> mkInstructions = new ArrayList<>();
+            mkInstructions.add(new InstructionApplyActions(listActionInfo));
 
             FlowEntity terminatingServiceTableFlowEntity = MDSALUtil
                     .buildFlowEntity(
@@ -408,17 +459,18 @@ public class ItmUtils {
                             0, 0, ITMConstants.COOKIE_ITM
                                     .add(BigInteger.valueOf(ITMConstants.LLDP_SERVICE_ID)),
                             mkMatches, mkInstructions);
-            if(addFlag)
+            if(addFlag) {
                 mdsalManager.installFlow(terminatingServiceTableFlowEntity);
-            else
+            } else {
                 mdsalManager.removeFlow(terminatingServiceTableFlowEntity);
+            }
         } catch (Exception e) {
             LOG.error("Error while setting up Table 36 for {}", dpnId, e);
         }
     }
 
     private static String getFlowRef(long termSvcTable, int svcId) {
-        return new StringBuffer().append(termSvcTable).append(svcId).toString();
+        return String.valueOf(termSvcTable) + svcId;
     }
     public static InstanceIdentifier<VtepConfigSchema> getVtepConfigSchemaIdentifier(String schemaName) {
         return InstanceIdentifier.builder(VtepConfigSchemas.class)
@@ -442,8 +494,8 @@ public class ItmUtils {
             if (!StringUtils.equalsIgnoreCase(schema.getSchemaName(), existingSchema.getSchemaName())
                     && schema.getSubnet().equals(existingSchema.getSubnet())) {
                 String subnetCidr = getSubnetCidrAsString(schema.getSubnet());
-                Preconditions.checkArgument(false, new StringBuilder("VTEP schema with subnet [").append(subnetCidr)
-                        .append("] already exists. Multiple VTEP schemas with same subnet is not allowed.").toString());
+                Preconditions.checkArgument(false, "VTEP schema with subnet [" + subnetCidr +
+                        "] already exists. Multiple VTEP schemas with same subnet is not allowed.");
             }
         }
         if (isNotEmpty(getDpnIdList(validSchema.getDpnIds()))) {
@@ -452,9 +504,8 @@ public class ItmUtils {
                     getDpnIdList(validSchema.getDpnIds()), existingSchemas);
             if (!lstDpns.isEmpty()) {
                 Preconditions.checkArgument(false,
-                        new StringBuilder("DPN's ").append(lstDpns).append(" already configured for transport zone ")
-                                .append(tzone).append(". Only one end point per transport Zone per Dpn is allowed.")
-                                .toString());
+                        "DPN's " + lstDpns + " already configured for transport zone " +
+                                tzone + ". Only one end point per transport Zone per Dpn is allowed.");
             }
             if (schema.getTunnelType().equals(TunnelTypeGre.class)){
                 validateForSingleGreTep(validSchema.getSchemaName(), getDpnIdList(validSchema.getDpnIds()), existingSchemas);
@@ -465,14 +516,13 @@ public class ItmUtils {
     private static void validateForSingleGreTep(String schemaName, List<BigInteger> lstDpnsForAdd,
                                                 List<VtepConfigSchema> existingSchemas) {
         for (VtepConfigSchema existingSchema : emptyIfNull(existingSchemas)) {
-            if ((TunnelTypeGre.class).equals(existingSchema.getTunnelType())
+            if (TunnelTypeGre.class.equals(existingSchema.getTunnelType())
                     && !StringUtils.equalsIgnoreCase(schemaName, existingSchema.getSchemaName())) {
                 List<BigInteger> lstConflictingDpns = new ArrayList<>(getDpnIdList(existingSchema.getDpnIds()));
                 lstConflictingDpns.retainAll(emptyIfNull(lstDpnsForAdd));
                 if (!lstConflictingDpns.isEmpty()) {
-                    String errMsg = new StringBuilder("DPN's ").append(lstConflictingDpns)
-                            .append(" already configured with GRE TEP. Mutiple GRE TEP's on a single DPN are not allowed.")
-                            .toString();
+                    String errMsg = "DPN's " + lstConflictingDpns +
+                            " already configured with GRE TEP. Mutiple GRE TEP's on a single DPN are not allowed.";
                     Preconditions.checkArgument(false, errMsg);
                 }
             }
@@ -482,7 +532,7 @@ public class ItmUtils {
         Preconditions.checkNotNull(schema);
         Preconditions.checkArgument(StringUtils.isNotBlank(schema.getSchemaName()));
         Preconditions.checkArgument(StringUtils.isNotBlank(schema.getPortName()));
-        Preconditions.checkArgument((schema.getVlanId() >= 0 && schema.getVlanId() < 4095),
+        Preconditions.checkArgument(schema.getVlanId() >= 0 && schema.getVlanId() < 4095,
                 "Invalid VLAN ID, range (0-4094)");
         Preconditions.checkArgument(StringUtils.isNotBlank(schema.getTransportZoneName()));
         Preconditions.checkNotNull(schema.getSubnet());
@@ -492,8 +542,8 @@ public class ItmUtils {
         if (gatewayIp != null) {
             String strGatewayIp = String.valueOf(gatewayIp.getValue());
             if (!strGatewayIp.equals(ITMConstants.DUMMY_IP_ADDRESS) && !subnetUtils.getInfo().isInRange(strGatewayIp)) {
-                Preconditions.checkArgument(false, new StringBuilder("Gateway IP address ").append(strGatewayIp)
-                        .append(" is not in subnet range ").append(subnetCidr).toString());
+                Preconditions.checkArgument(false, "Gateway IP address " + strGatewayIp +
+                        " is not in subnet range " + subnetCidr);
             }
         }
         ItmUtils.getExcludeIpAddresses(schema.getExcludeIpFilter(), subnetUtils.getInfo());
@@ -504,9 +554,8 @@ public class ItmUtils {
             tunnelType = ITMConstants.TUNNEL_TYPE_VXLAN;
         } else {
             tunnelType = StringUtils.upperCase(tunnelType);
-            String error = new StringBuilder("Invalid tunnel type. Valid values: ")
-                    .append(ITMConstants.TUNNEL_TYPE_VXLAN).append(" | ").append(ITMConstants.TUNNEL_TYPE_GRE)
-                    .toString();
+            String error = "Invalid tunnel type. Valid values: " +
+                    ITMConstants.TUNNEL_TYPE_VXLAN + " | " + ITMConstants.TUNNEL_TYPE_GRE;
             Preconditions.checkArgument(ITMConstants.TUNNEL_TYPE_VXLAN.equals(tunnelType)
                     || ITMConstants.TUNNEL_TYPE_GRE.equals(tunnelType), error);
         }
@@ -533,10 +582,11 @@ public class ItmUtils {
         IpAddress gatewayIpObj = StringUtils.isBlank(gatewayIp) ? null : new IpAddress(gatewayIp.toCharArray());
         IpPrefix subnet = StringUtils.isBlank(subnetMask) ? null : new IpPrefix(subnetMask.toCharArray());
         Class<? extends TunnelTypeBase> tunType ;
-        if( tunnelType.equals(ITMConstants.TUNNEL_TYPE_VXLAN))
+        if( tunnelType.equals(ITMConstants.TUNNEL_TYPE_VXLAN)) {
             tunType = TunnelTypeVxlan.class ;
-        else
+        } else {
             tunType = TunnelTypeGre.class ;
+        }
         VtepConfigSchemaBuilder schemaBuilder = new VtepConfigSchemaBuilder().setSchemaName(schemaName)
                 .setPortName(portName).setVlanId(vlanId).setSubnet(subnet).setGatewayIp(gatewayIpObj)
                 .setTransportZoneName(transportZone).setTunnelType(tunType).setDpnIds(getDpnIdsListFromBigInt(dpnIds))
@@ -555,23 +605,20 @@ public class ItmUtils {
                 String strStartIp = StringUtils.trim(arrIpRange[0]);
                 String strEndIp = StringUtils.trim(arrIpRange[1]);
                 Preconditions.checkArgument(InetAddresses.isInetAddress(strStartIp),
-                        new StringBuilder("Invalid exclude IP filter: invalid IP address value ").append(strStartIp)
-                                .toString());
+                        "Invalid exclude IP filter: invalid IP address value " + strStartIp);
                 Preconditions.checkArgument(InetAddresses.isInetAddress(strEndIp),
-                        new StringBuilder("Invalid exclude IP filter: invalid IP address value ").append(strEndIp)
-                                .toString());
+                        "Invalid exclude IP filter: invalid IP address value " + strEndIp);
                 Preconditions.checkArgument(subnetInfo.isInRange(strStartIp),
-                        new StringBuilder("Invalid exclude IP filter: IP address [").append(strStartIp)
-                                .append("] not in subnet range ").append(subnetInfo.getCidrSignature()).toString());
+                        "Invalid exclude IP filter: IP address [" + strStartIp +
+                                "] not in subnet range " + subnetInfo.getCidrSignature());
                 Preconditions.checkArgument(subnetInfo.isInRange(strEndIp),
-                        new StringBuilder("Invalid exclude IP filter: IP address [").append(strEndIp)
-                                .append("] not in subnet range ").append(subnetInfo.getCidrSignature()).toString());
+                        "Invalid exclude IP filter: IP address [" + strEndIp +
+                                "] not in subnet range " + subnetInfo.getCidrSignature());
                 int startIp = subnetInfo.asInteger(strStartIp);
                 int endIp = subnetInfo.asInteger(strEndIp);
 
                 Preconditions.checkArgument(startIp < endIp,
-                        new StringBuilder("Invalid exclude IP filter: Invalid range [").append(ip).append("] ")
-                                .toString());
+                        "Invalid exclude IP filter: Invalid range [" + ip + "] ");
                 for (int i = startIp; i <= endIp; i++) {
                     String ipAddress = ipFormat(toIpArray(i));
                     validateAndAddIpAddressToList(subnetInfo, lstIpAddress, ipAddress);
@@ -586,16 +633,16 @@ public class ItmUtils {
                                                       String ipAddress) {
         String ip = StringUtils.trim(ipAddress);
         Preconditions.checkArgument(InetAddresses.isInetAddress(ip),
-                new StringBuilder("Invalid exclude IP filter: invalid IP address value ").append(ip).toString());
+                "Invalid exclude IP filter: invalid IP address value " + ip);
         Preconditions.checkArgument(subnetInfo.isInRange(ip),
-                new StringBuilder("Invalid exclude IP filter: IP address [").append(ip).append("] not in subnet range ")
-                        .append(subnetInfo.getCidrSignature()).toString());
+                "Invalid exclude IP filter: IP address [" + ip + "] not in subnet range " +
+                        subnetInfo.getCidrSignature());
         lstIpAddress.add(new IpAddress(ip.toCharArray()));
     }
     private static int[] toIpArray(int val) {
         int[] ret = new int[4];
         for (int j = 3; j >= 0; --j) {
-            ret[j] |= ((val >>> 8 * (3 - j)) & (0xff));
+            ret[j] |= val >>> 8 * (3 - j) & 0xff;
         }
         return ret;
     }
@@ -615,13 +662,12 @@ public class ItmUtils {
         if ((lstDpnsForAdd == null || lstDpnsForAdd.isEmpty())
                 && (lstDpnsForDelete == null || lstDpnsForDelete.isEmpty())) {
             Preconditions.checkArgument(false,
-                    new StringBuilder("DPN ID list for add | delete is null or empty in schema ").append(schemaName)
-                            .toString());
+                    "DPN ID list for add | delete is null or empty in schema " + schemaName);
         }
         VtepConfigSchema schema = itmProvider.getVtepConfigSchema(schemaName);
         if (schema == null) {
-            Preconditions.checkArgument(false, new StringBuilder("Specified VTEP Schema [").append(schemaName)
-                    .append("] doesn't exists!").toString());
+            Preconditions.checkArgument(false, "Specified VTEP Schema [" + schemaName +
+                    "] doesn't exists!");
         }
         List<BigInteger> existingDpnIds = getDpnIdList(schema.getDpnIds());
         if (isNotEmpty(lstDpnsForAdd)) {
@@ -629,8 +675,8 @@ public class ItmUtils {
             List<BigInteger> lstAlreadyExistingDpns = new ArrayList<>(existingDpnIds);
             lstAlreadyExistingDpns.retainAll(lstDpnsForAdd);
             Preconditions.checkArgument(lstAlreadyExistingDpns.isEmpty(),
-                    new StringBuilder("DPN ID's ").append(lstAlreadyExistingDpns)
-                            .append(" already exists in VTEP schema [").append(schemaName).append("]").toString());
+                    "DPN ID's " + lstAlreadyExistingDpns +
+                            " already exists in VTEP schema [" + schemaName + "]");
             //    }
             if (schema.getTunnelType().equals(TunnelTypeGre.class)) {
                 validateForSingleGreTep(schema.getSchemaName(), lstDpnsForAdd, itmProvider.getAllVtepConfigSchemas());
@@ -638,29 +684,29 @@ public class ItmUtils {
         }
         if (isNotEmpty(lstDpnsForDelete)) {
             if (existingDpnIds == null || existingDpnIds.isEmpty()) {
-                StringBuilder builder = new StringBuilder("DPN ID's ").append(lstDpnsForDelete)
-                        .append(" specified for delete from VTEP schema [").append(schemaName)
-                        .append("] are not configured in the schema.");
-                Preconditions.checkArgument(false, builder.toString());
+                String builder = "DPN ID's " + lstDpnsForDelete +
+                        " specified for delete from VTEP schema [" + schemaName +
+                        "] are not configured in the schema.";
+                Preconditions.checkArgument(false, builder);
             } else if (!existingDpnIds.containsAll(lstDpnsForDelete)) {
                 List<BigInteger> lstConflictingDpns = new ArrayList<>(lstDpnsForDelete);
                 lstConflictingDpns.removeAll(existingDpnIds);
-                StringBuilder builder = new StringBuilder("DPN ID's ").append(lstConflictingDpns)
-                        .append(" specified for delete from VTEP schema [").append(schemaName)
-                        .append("] are not configured in the schema.");
-                Preconditions.checkArgument(false, builder.toString());
+                String builder = "DPN ID's " + lstConflictingDpns +
+                        " specified for delete from VTEP schema [" + schemaName +
+                        "] are not configured in the schema.";
+                Preconditions.checkArgument(false, builder);
             }
         }
         return schema;
     }
     public static String getSubnetCidrAsString(IpPrefix subnet) {
-        return (subnet == null) ? StringUtils.EMPTY : String.valueOf(subnet.getValue());
+        return subnet == null ? StringUtils.EMPTY : String.valueOf(subnet.getValue());
     }
     public static <T> List<T> emptyIfNull(List<T> list) {
-        return (list == null) ? Collections.<T> emptyList() : list;
+        return list == null ? Collections.emptyList() : list;
     }
     public static <T> boolean isEmpty(Collection<T> collection) {
-        return (collection == null || collection.isEmpty()) ? true : false;
+        return collection == null || collection.isEmpty();
     }
     public static <T> boolean isNotEmpty(Collection<T> collection) {
         return !isEmpty(collection);
@@ -696,7 +742,7 @@ public class ItmUtils {
     }
 
     public static List<BigInteger> getDpnIdList( List<DpnIds> dpnIds ) {
-        List<BigInteger> dpnList = new ArrayList<BigInteger>() ;
+        List<BigInteger> dpnList = new ArrayList<>() ;
         for( DpnIds dpn : dpnIds) {
             dpnList.add(dpn.getDPN()) ;
         }
@@ -704,7 +750,7 @@ public class ItmUtils {
     }
 
     public static List<DpnIds> getDpnIdsListFromBigInt( List<BigInteger> dpnIds) {
-        List<DpnIds> dpnIdList = new ArrayList<DpnIds>() ;
+        List<DpnIds> dpnIdList = new ArrayList<>() ;
         DpnIdsBuilder builder = new DpnIdsBuilder() ;
         for( BigInteger dpnId : dpnIds) {
             dpnIdList.add(builder.setKey(new DpnIdsKey(dpnId)).setDPN(dpnId).build() );
@@ -721,48 +767,70 @@ public class ItmUtils {
         InstanceIdentifier<org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.Interface> id = idBuilder.build();
         return id;
     }
-    public static Boolean readMonitoringStateFromDS(DataBroker dataBroker) {
+    public static Boolean readMonitoringStateFromCache(DataBroker dataBroker) {
         InstanceIdentifier<TunnelMonitorParams> iid = InstanceIdentifier.create(TunnelMonitorParams.class);
-        Optional<TunnelMonitorParams> TunnelMonitorParamsOptional = ItmUtils.read(LogicalDatastoreType.CONFIGURATION,
-                iid, dataBroker);
-        if(TunnelMonitorParamsOptional.isPresent())
-            return TunnelMonitorParamsOptional.get().isEnabled();
-        return null;
+        TunnelMonitorParams tunnelMonitorParams = (TunnelMonitorParams) DataStoreCache.get(ITMConstants.ITM_MONIRORING_PARAMS_CACHE_NAME,iid,"MonitorParams",dataBroker,true);
+        if(tunnelMonitorParams!=null) {
+            return tunnelMonitorParams.isEnabled();
+        } else {
+            return ITMConstants.DEFAULT_MONITOR_ENABLED;
+        }
     }
 
-    public static Integer readMonitorIntervalfromDS(DataBroker dataBroker) {
+    public static Integer readMonitorIntervalfromCache(DataBroker dataBroker) {
         InstanceIdentifier<TunnelMonitorInterval> iid = InstanceIdentifier.create(TunnelMonitorInterval.class);
-        Optional<TunnelMonitorInterval> tunnelMonitorIOptional = ItmUtils.read(LogicalDatastoreType.CONFIGURATION, iid, dataBroker);
-        if(tunnelMonitorIOptional.isPresent())
-            return tunnelMonitorIOptional.get().getInterval();
+        TunnelMonitorInterval tunnelMonitorIOptional = (TunnelMonitorInterval)DataStoreCache.get(ITMConstants.ITM_MONIRORING_PARAMS_CACHE_NAME,iid,"Interval",dataBroker,true);
+        if(tunnelMonitorIOptional!=null) {
+            return tunnelMonitorIOptional.getInterval();
+        }
         return null;
 
     }
 
     public static Integer determineMonitorInterval(DataBroker dataBroker) {
-        Integer monitorInterval = ItmUtils.readMonitorIntervalfromDS(dataBroker);
+        Integer monitorInterval = ItmUtils.readMonitorIntervalfromCache(dataBroker);
         LOG.debug("determineMonitorInterval: monitorInterval from DS = {}", monitorInterval);
         if(monitorInterval==null){
-            Class<? extends TunnelMonitoringTypeBase> monitoringProtocol = determineMonitorProtocol(dataBroker);
-            if(monitoringProtocol.getName().contains("Bfd"))
+            Class<? extends TunnelMonitoringTypeBase> monitorProtocol = determineMonitorProtocol(dataBroker);
+            if(monitorProtocol.isAssignableFrom(TunnelMonitoringTypeBfd.class)) {
                 monitorInterval = ITMConstants.BFD_DEFAULT_MONITOR_INTERVAL;
-            else
+            } else {
                 monitorInterval = ITMConstants.DEFAULT_MONITOR_INTERVAL;
+            }
         }
         LOG.debug("determineMonitorInterval: monitorInterval = {}", monitorInterval);
+        InstanceIdentifier<TunnelMonitorInterval> iid = InstanceIdentifier.builder(TunnelMonitorInterval.class).build();
+        TunnelMonitorInterval intervalBuilder = new TunnelMonitorIntervalBuilder().setInterval(monitorInterval).build();
+        ItmUtils.asyncUpdate(LogicalDatastoreType.OPERATIONAL,iid, intervalBuilder, dataBroker, ItmUtils.DEFAULT_CALLBACK);
         return monitorInterval;
     }
 
+    public static List<String> getInternalTunnelInterfaces(DataBroker dataBroker){
+        List<String> tunnelList = new ArrayList<>();
+        Collection<String> internalInterfaces = itmCache.getAllInternalInterfaces();
+        if(internalInterfaces == null) {
+            updateTunnelsCache(dataBroker);
+            internalInterfaces = itmCache.getAllInternalInterfaces();
+        }
+        LOG.debug("ItmUtils.getTunnelList Cache Internal Interfaces size: {} ", internalInterfaces.size());
+        if(internalInterfaces!=null) {
+            tunnelList.addAll(internalInterfaces);
+        }
+        LOG.trace("ItmUtils.getTunnelList Internal: {}", tunnelList);
+        return tunnelList;
+    }
+
     public static List<String> getTunnelsofTzone(List<HwVtep> hwVteps, String tzone, DataBroker dataBroker, Boolean hwVtepsExist) {
 
-        List<String> tunnels = new ArrayList<String>();
+        List<String> tunnels = new ArrayList<>();
         InstanceIdentifier<TransportZone> path = InstanceIdentifier.builder(TransportZones.class).
                 child(TransportZone.class, new TransportZoneKey(tzone)).build();
         Optional<TransportZone> tZoneOptional = ItmUtils.read(LogicalDatastoreType.CONFIGURATION, path, dataBroker);
-        Class<? extends TunnelTypeBase> tunType = tZoneOptional.get().getTunnelType();
         if (tZoneOptional.isPresent()) {
-            if (tZoneOptional.get().getSubnets() != null && !tZoneOptional.get().getSubnets().isEmpty()) {
-                for (Subnets sub : tZoneOptional.get().getSubnets()) {
+            TransportZone transportZone = tZoneOptional.get();
+            Class<? extends TunnelTypeBase> tunType = transportZone.getTunnelType();
+            if (transportZone.getSubnets() != null && !transportZone.getSubnets().isEmpty()) {
+                for (Subnets sub : transportZone.getSubnets()) {
                     if (sub.getVteps() != null && !sub.getVteps().isEmpty()) {
                         for (Vteps vtepLocal : sub.getVteps()) {
                             for (Vteps vtepRemote : sub.getVteps()) {
@@ -774,8 +842,9 @@ public class ItmUtils {
                                     Optional<InternalTunnel> TunnelsOptional =
                                             ItmUtils.read(LogicalDatastoreType.CONFIGURATION, intIID, dataBroker);
                                     if (TunnelsOptional.isPresent()) {
-                                        LOG.trace("Internal Tunnel added {}",TunnelsOptional.get().getTunnelInterfaceName());
-                                        tunnels.add(TunnelsOptional.get().getTunnelInterfaceName());
+                                        String tunnelInterfaceName = TunnelsOptional.get().getTunnelInterfaceName();
+                                        LOG.trace("Internal Tunnel added {}", tunnelInterfaceName);
+                                        tunnels.add(tunnelInterfaceName);
                                     }
                                 }
                             }
@@ -791,13 +860,13 @@ public class ItmUtils {
                     }
                 }
             }
-        }
-        if (hwVtepsExist) {
-            for (HwVtep hwVtep : hwVteps) {
-                for (HwVtep hwVtepOther : hwVteps) {
-                    if (!hwVtep.getHwIp().equals(hwVtepOther.getHwIp())) {
-                        tunnels.add(getExtTunnel(hwVtep.getNode_id(), hwVtepOther.getNode_id(), tunType, dataBroker));
-                        tunnels.add(getExtTunnel(hwVtepOther.getNode_id(), hwVtep.getNode_id(), tunType, dataBroker));
+            if (hwVtepsExist) {
+                for (HwVtep hwVtep : hwVteps) {
+                    for (HwVtep hwVtepOther : hwVteps) {
+                        if (!hwVtep.getHwIp().equals(hwVtepOther.getHwIp())) {
+                            tunnels.add(getExtTunnel(hwVtep.getNode_id(), hwVtepOther.getNode_id(), tunType, dataBroker));
+                            tunnels.add(getExtTunnel(hwVtepOther.getNode_id(), hwVtep.getNode_id(), tunType, dataBroker));
+                        }
                     }
                 }
             }
@@ -806,28 +875,31 @@ public class ItmUtils {
     }
 
     public static List<String> getInternalTunnelsofTzone(String tzone, DataBroker dataBroker) {
-        List<String> tunnels = new ArrayList<String>();
+        List<String> tunnels = new ArrayList<>();
         LOG.trace("Getting internal tunnels of {}",tzone);
         InstanceIdentifier<TransportZone> path = InstanceIdentifier.builder(TransportZones.class).
                 child(TransportZone.class, new TransportZoneKey(tzone)).build();
         Optional<TransportZone> tZoneOptional = ItmUtils.read(LogicalDatastoreType.CONFIGURATION, path, dataBroker);
         if (tZoneOptional.isPresent()) {
-            if (tZoneOptional.get().getSubnets() != null && !tZoneOptional.get().getSubnets().isEmpty()) {
-                for (Subnets sub : tZoneOptional.get().getSubnets()) {
+            TransportZone transportZone = tZoneOptional.get();
+            if (transportZone.getSubnets() != null && !transportZone.getSubnets().isEmpty()) {
+                for (Subnets sub : transportZone.getSubnets()) {
                     if (sub.getVteps() != null && !sub.getVteps().isEmpty()) {
                         for (Vteps vtepLocal : sub.getVteps()) {
                             for (Vteps vtepRemote : sub.getVteps()) {
                                 if (!vtepLocal.equals(vtepRemote)) {
-                                    InternalTunnelKey key = new InternalTunnelKey(vtepRemote.getDpnId(), vtepLocal.getDpnId(), tZoneOptional.get().getTunnelType());
+                                    InternalTunnelKey key =
+                                            new InternalTunnelKey(vtepRemote.getDpnId(), vtepLocal.getDpnId(),
+                                                    transportZone.getTunnelType());
                                     InstanceIdentifier<InternalTunnel> intIID =
                                             InstanceIdentifier.builder(TunnelList.class).
                                                     child(InternalTunnel.class, key).build();
-                                    Optional<InternalTunnel> TunnelsOptional =
+                                    Optional<InternalTunnel> tunnelsOptional =
                                             ItmUtils.read(LogicalDatastoreType.CONFIGURATION, intIID, dataBroker);
-                                    if (TunnelsOptional.isPresent()) {
-                                        LOG.trace("Internal Tunnel added {}",
-                                                TunnelsOptional.get().getTunnelInterfaceName());
-                                        tunnels.add(TunnelsOptional.get().getTunnelInterfaceName());
+                                    if (tunnelsOptional.isPresent()) {
+                                        String tunnelInterfaceName = tunnelsOptional.get().getTunnelInterfaceName();
+                                        LOG.trace("Internal Tunnel added {}", tunnelInterfaceName);
+                                        tunnels.add(tunnelInterfaceName);
                                     }
                                 }
                             }
@@ -844,11 +916,12 @@ public class ItmUtils {
         ExternalTunnelKey key = getExternalTunnelKey(dpId, node_id, tunType);
         InstanceIdentifier<ExternalTunnel> intIID = InstanceIdentifier.builder(ExternalTunnelList.class).
                 child(ExternalTunnel.class, key).build();
-        Optional<ExternalTunnel> TunnelsOptional =
+        Optional<ExternalTunnel> tunnelsOptional =
                 ItmUtils.read(LogicalDatastoreType.CONFIGURATION, intIID, dataBroker);
-        if (TunnelsOptional.isPresent()) {
-            LOG.trace("ext tunnel returned {} ",TunnelsOptional.get().getTunnelInterfaceName());
-            return TunnelsOptional.get().getTunnelInterfaceName();
+        if (tunnelsOptional.isPresent()) {
+            String tunnelInterfaceName = tunnelsOptional.get().getTunnelInterfaceName();
+            LOG.trace("ext tunnel returned {} ", tunnelInterfaceName);
+            return tunnelInterfaceName;
         }
         return null;
     }
@@ -872,11 +945,7 @@ public class ItmUtils {
     }
     public static TunnelList getAllInternalTunnels(DataBroker broker) {
         InstanceIdentifier<TunnelList> tunnelListInstanceIdentifier = InstanceIdentifier.builder(TunnelList.class).build();
-        Optional<TunnelList> tunnelList = read(LogicalDatastoreType.CONFIGURATION, tunnelListInstanceIdentifier, broker);
-        if (tunnelList.isPresent()) {
-            return tunnelList.get();
-        }
-        return null;
+        return read(LogicalDatastoreType.CONFIGURATION, tunnelListInstanceIdentifier, broker).orNull();
     }
     public static InternalTunnel getInternalTunnel(String interfaceName, DataBroker broker) {
         InternalTunnel internalTunnel = null;
@@ -917,21 +986,19 @@ public class ItmUtils {
     }
     public static String convertTunnelTypetoString(Class<? extends TunnelTypeBase> tunType ) {
         String tunnelType = ITMConstants.TUNNEL_TYPE_VXLAN;
-        if( tunType.equals(TunnelTypeVxlan.class))
+        if( tunType.equals(TunnelTypeVxlan.class)) {
             tunnelType = ITMConstants.TUNNEL_TYPE_VXLAN ;
-        else if( tunType.equals(TunnelTypeGre.class) )
+        } else if( tunType.equals(TunnelTypeGre.class) ) {
             tunnelType = ITMConstants.TUNNEL_TYPE_GRE ;
-        else if (tunnelType.equals(TunnelTypeMplsOverGre.class))
-            tunnelType = ITMConstants.TUNNEL_TYPE_MPLS_OVER_GRE;
+        } else if (tunnelType.equals(TunnelTypeMplsOverGre.class)) {
+            tunnelType = ITMConstants.TUNNEL_TYPE_MPLSoGRE;
+        }
         return tunnelType ;
     }
 
 
     public static boolean isItmIfType(Class<? extends InterfaceType> ifType) {
-        if( (ifType != null) && (ifType.isAssignableFrom(Tunnel.class)) ) {
-            return true;
-        }
-        return false;
+        return ifType != null && ifType.isAssignableFrom(Tunnel.class);
     }
 
     public static StateTunnelListKey getTunnelStateKey( org.opendaylight.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev140508.interfaces.state.Interface iface) {
@@ -995,34 +1062,67 @@ public class ItmUtils {
         return result;
     }
 
-    public static Class<? extends TunnelMonitoringTypeBase> readMonitoringProtocolFromDS(DataBroker dataBroker) {
+    public static Class<? extends TunnelMonitoringTypeBase> readMonitoringProtocolFromCache(DataBroker dataBroker) {
         InstanceIdentifier<TunnelMonitorParams> iid = InstanceIdentifier.create(TunnelMonitorParams.class);
-        Optional<TunnelMonitorParams> TunnelMonitorParamsOptional = ItmUtils.read(LogicalDatastoreType.CONFIGURATION,
-                iid, dataBroker);
-        if(TunnelMonitorParamsOptional.isPresent())
-            return TunnelMonitorParamsOptional.get().getMonitorProtocol();
+        TunnelMonitorParams tunnelMonitorParams = (TunnelMonitorParams) DataStoreCache.get(ITMConstants.ITM_MONIRORING_PARAMS_CACHE_NAME,iid,"MonitorParams",dataBroker,true);
+        if(tunnelMonitorParams!=null) {
+            return tunnelMonitorParams.getMonitorProtocol();
+        }
         return null;
     }
 
     public static Class<? extends TunnelMonitoringTypeBase> determineMonitorProtocol(DataBroker dataBroker) {
-        Class<? extends TunnelMonitoringTypeBase> monitoringProtocol = ItmUtils.readMonitoringProtocolFromDS(dataBroker);
+        Class<? extends TunnelMonitoringTypeBase> monitoringProtocol = ItmUtils.readMonitoringProtocolFromCache(dataBroker);
         LOG.debug("determineMonitorProtocol: monitorProtocol from DS = {}", monitoringProtocol);
-        if(monitoringProtocol==null)
+        if(monitoringProtocol==null) {
             monitoringProtocol = ITMConstants.DEFAULT_MONITOR_PROTOCOL;
+        }
         LOG.debug("determineMonitorProtocol: monitorProtocol = {}", monitoringProtocol);
+        Boolean monitorState = ItmUtils.readMonitoringStateFromCache(dataBroker);
+        if(monitorState==null) {
+            monitorState = true;
+        }
+        LOG.debug("determineMonitorProtocol: monitorState = {}", monitorState);
+        InstanceIdentifier<TunnelMonitorParams> iid = InstanceIdentifier.builder(TunnelMonitorParams.class).build();
+        TunnelMonitorParams protocolBuilder = new TunnelMonitorParamsBuilder().setEnabled(monitorState).setMonitorProtocol(monitoringProtocol).build();
+        ItmUtils.asyncUpdate(LogicalDatastoreType.OPERATIONAL,iid, protocolBuilder, dataBroker, ItmUtils.DEFAULT_CALLBACK);
         return monitoringProtocol;
     }
 
-
     public static List<DcGatewayIp> getDcGatewayIpList(DataBroker broker){
         InstanceIdentifier<DcGatewayIpList> dcGatewayIpListid = InstanceIdentifier.builder(DcGatewayIpList.class).build();
         Optional<DcGatewayIpList> dcGatewayIpListConfig = ItmUtils.read(LogicalDatastoreType.CONFIGURATION, dcGatewayIpListid, broker);
         if(dcGatewayIpListConfig.isPresent()){
             DcGatewayIpList containerList = dcGatewayIpListConfig.get();
             if(containerList != null){
-                return (containerList.getDcGatewayIp());
+                return containerList.getDcGatewayIp();
             }
         }
         return null;
     }
+
+    public static boolean falseIfNull(Boolean value) {
+        return value == null ? false : value;
+    }
+
+    public static <T> List<T> getIntersection(List<T> list1, List<T> list2) {
+        List<T> list = new ArrayList<>();
+        for (T t : list1) {
+            if(list2.contains(t)) {
+                list.add(t);
+            }
+        }
+        return list;
+    }
+
+    public static void addTransportZoneMembership(List<TzMembership> zones, String zoneName) {
+        zones.add(new TzMembershipBuilder().setZoneName(zoneName).build());
+    }
+
+    public static  List<TzMembership> createTransportZoneMembership(String zoneName) {
+        List<TzMembership> zones = new ArrayList<>();
+        zones.add(new TzMembershipBuilder().setZoneName(zoneName).build());
+        return zones;
+    }
+
 }