diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/AccessInfo.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/AccessInfo.java
index 3728cbe..d8f1504 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/AccessInfo.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/AccessInfo.java
@@ -49,7 +49,7 @@
      *
      * @return site id
      */
-    String siteId() {
+    public String siteId() {
         return siteId;
     }
 
@@ -58,7 +58,7 @@
      *
      * @return access id
      */
-    String accessId() {
+    public String accessId() {
         return accessId;
     }
 
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpDriverInfo.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpDriverInfo.java
index 151f3e5..ec7058f 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpDriverInfo.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpDriverInfo.java
@@ -47,7 +47,7 @@
      *
      * @return model id level
      */
-    BgpModelIdLevel modIdLevel() {
+    public BgpModelIdLevel modIdLevel() {
         return modIdLevel;
     }
 
@@ -56,8 +56,7 @@
      *
      * @return device id
      */
-    String devId() {
+    public String devId() {
         return devId;
     }
-
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpInfo.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpInfo.java
index e461b24..8c21061 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpInfo.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/BgpInfo.java
@@ -46,7 +46,7 @@
      *
      * @return protocol info map.
      */
-    Map<RouteProtocol, ProtocolInfo> protocolInfo() {
+    public Map<RouteProtocol, ProtocolInfo> protocolInfo() {
         return protocolInfo;
     }
 
@@ -55,7 +55,7 @@
      *
      * @param protocolInfo protocol info map
      */
-    void protocolInfo(Map<RouteProtocol, ProtocolInfo> protocolInfo) {
+    public void protocolInfo(Map<RouteProtocol, ProtocolInfo> protocolInfo) {
         this.protocolInfo = protocolInfo;
     }
 
@@ -65,7 +65,7 @@
      * @param route route protocol
      * @param info  protocol info
      */
-    void addProtocolInfo(RouteProtocol route, ProtocolInfo info) {
+    public void addProtocolInfo(RouteProtocol route, ProtocolInfo info) {
         if (protocolInfo == null) {
             protocolInfo = new HashMap<>();
         }
@@ -77,7 +77,7 @@
      *
      * @return VPN name
      */
-    String vpnName() {
+    public String vpnName() {
         return vpnName;
     }
 
@@ -86,7 +86,7 @@
      *
      * @param vpnName VPN name
      */
-    void vpnName(String vpnName) {
+    public void vpnName(String vpnName) {
         this.vpnName = vpnName;
     }
 
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/DeviceInfo.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/DeviceInfo.java
index 8b4421e..4198ee8 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/DeviceInfo.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/DeviceInfo.java
@@ -63,7 +63,7 @@
      *
      * @return device id
      */
-    DeviceId deviceId() {
+    public DeviceId deviceId() {
         return deviceId;
     }
 
@@ -72,7 +72,7 @@
      *
      * @param ifName interface name
      */
-    void addIfName(String ifName) {
+    public void addIfName(String ifName) {
         if (ifNames == null) {
             ifNames = new LinkedList<>();
         }
@@ -84,7 +84,7 @@
      *
      * @return interface names
      */
-    List<String> ifNames() {
+    public List<String> ifNames() {
         return ifNames;
     }
 
@@ -93,7 +93,7 @@
      *
      * @param ifNames interface names
      */
-    void ifNames(List<String> ifNames) {
+    public void ifNames(List<String> ifNames) {
         this.ifNames = ifNames;
     }
 
@@ -102,7 +102,7 @@
      *
      * @return BGP info
      */
-    BgpInfo bgpInfo() {
+    public BgpInfo bgpInfo() {
         return bgpInfo;
     }
 
@@ -111,7 +111,7 @@
      *
      * @param bgpInfo BGP info
      */
-    void bgpInfo(BgpInfo bgpInfo) {
+    public void bgpInfo(BgpInfo bgpInfo) {
         this.bgpInfo = bgpInfo;
     }
 
@@ -120,7 +120,7 @@
      *
      * @return network accesses
      */
-    List<AccessInfo> accesses() {
+    public List<AccessInfo> accesses() {
         return accesses;
     }
 
@@ -129,7 +129,7 @@
      *
      * @param accesses network accesses
      */
-    void accesses(List<AccessInfo> accesses) {
+    public void accesses(List<AccessInfo> accesses) {
         this.accesses = accesses;
     }
 
@@ -138,7 +138,7 @@
      *
      * @param accessInfo access info
      */
-    void addAccessInfo(AccessInfo accessInfo) {
+    public void addAccessInfo(AccessInfo accessInfo) {
         if (accesses == null) {
             accesses = new LinkedList<>();
         }
@@ -154,8 +154,8 @@
      * @param modelData std device model object data
      * @return driver instance model object data
      */
-    ModelObjectData processCreateInstance(DriverService driverSvc,
-                                          ModelObjectData modelData) {
+    public ModelObjectData processCreateInstance(DriverService driverSvc,
+                                                 ModelObjectData modelData) {
         // TODO: Need to call the behaviour.
         return null;
     }
@@ -169,8 +169,8 @@
      * @param modData   std device model object data
      * @return driver interface model object data
      */
-    ModelObjectData processCreateInterface(DriverService driverSvc,
-                                           ModelObjectData modData) {
+    public ModelObjectData processCreateInterface(DriverService driverSvc,
+                                                  ModelObjectData modData) {
         // TODO: Need to call the behaviour.
         return null;
     }
@@ -185,9 +185,9 @@
      * @param driverInfo driver config details
      * @return driver BGP model object data
      */
-    ModelObjectData processCreateBgpInfo(DriverService driverSvc,
-                                         BgpInfo bgpInfo,
-                                         BgpDriverInfo driverInfo) {
+    public ModelObjectData processCreateBgpInfo(DriverService driverSvc,
+                                                BgpInfo bgpInfo,
+                                                BgpDriverInfo driverInfo) {
         // TODO: Need to call the behaviour.
         return null;
     }
@@ -201,7 +201,7 @@
      * @param modData   model object data
      * @return driver instance model object data
      */
-    ModelObjectData processDeleteInstance(DriverService driverSvc,
+    public ModelObjectData processDeleteInstance(DriverService driverSvc,
                                           ModelObjectData modData) {
         // TODO: Need to call the behaviour.
         return null;
@@ -216,7 +216,7 @@
      * @param objectData model object data
      * @return driver interface model object data
      */
-    ModelObjectData processDeleteInterface(DriverService driverSvc,
+    public ModelObjectData processDeleteInterface(DriverService driverSvc,
                                            ModelObjectData objectData) {
         // TODO: Need to call the behaviour.
         return null;
@@ -232,7 +232,7 @@
      * @param driverInfo driver config details
      * @return driver BGP model object data
      */
-    ModelObjectData processDeleteBgpInfo(DriverService driverSvc,
+    public ModelObjectData processDeleteBgpInfo(DriverService driverSvc,
                                          BgpInfo bgpInfo,
                                          BgpDriverInfo driverInfo) {
         // TODO: Need to call the behaviour.
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/FullMeshVpnConfig.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/FullMeshVpnConfig.java
index 8802fc0..76bb756 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/FullMeshVpnConfig.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/FullMeshVpnConfig.java
@@ -39,7 +39,7 @@
      *
      * @return RT value
      */
-    String rt() {
+    public String rt() {
         return rt;
     }
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/HubSpokeVpnConfig.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/HubSpokeVpnConfig.java
index d305ae3..a2dfb96 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/HubSpokeVpnConfig.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/HubSpokeVpnConfig.java
@@ -53,7 +53,7 @@
      *
      * @return RT value
      */
-    String hubImpRt() {
+    public String hubImpRt() {
         return hubImpRt;
     }
 
@@ -62,7 +62,7 @@
      *
      * @param hubImpRt RT value
      */
-    void hubImpRt(String hubImpRt) {
+    public void hubImpRt(String hubImpRt) {
         this.hubImpRt = hubImpRt;
     }
 
@@ -71,7 +71,7 @@
      *
      * @return RT value
      */
-    String hubExpRt() {
+    public String hubExpRt() {
         return hubExpRt;
     }
 
@@ -80,7 +80,7 @@
      *
      * @param hubExpRt RT value
      */
-    void hubExpRt(String hubExpRt) {
+    public void hubExpRt(String hubExpRt) {
         this.hubExpRt = hubExpRt;
     }
 
@@ -89,7 +89,7 @@
      *
      * @return RT value
      */
-    String spokeImpRt() {
+    public String spokeImpRt() {
         return spokeImpRt;
     }
 
@@ -98,7 +98,7 @@
      *
      * @param spokeImpRt RT value
      */
-    void spokeImpRt(String spokeImpRt) {
+    public void spokeImpRt(String spokeImpRt) {
         this.spokeImpRt = spokeImpRt;
     }
 
@@ -107,7 +107,7 @@
      *
      * @return RT value
      */
-    String spokeExpRt() {
+    public String spokeExpRt() {
         return spokeExpRt;
     }
 
@@ -116,7 +116,7 @@
      *
      * @param spokeExpRt RT value
      */
-    void spokeExpRt(String spokeExpRt) {
+    public void spokeExpRt(String spokeExpRt) {
         this.spokeExpRt = spokeExpRt;
     }
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/InterfaceInfo.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/InterfaceInfo.java
index ecdddb6..48b408a 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/InterfaceInfo.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/InterfaceInfo.java
@@ -55,7 +55,7 @@
      *
      * @return device info
      */
-    DeviceInfo devInfo() {
+    public DeviceInfo devInfo() {
         return devInfo;
     }
 
@@ -64,7 +64,7 @@
      *
      * @return interface name
      */
-    String intName() {
+    public String intName() {
         return intName;
     }
 
@@ -73,7 +73,7 @@
      *
      * @return VPN name
      */
-    String vpnName() {
+    public String vpnName() {
         return vpnName;
     }
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/ProtocolInfo.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/ProtocolInfo.java
index 1692127..1b873e7 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/ProtocolInfo.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/ProtocolInfo.java
@@ -65,7 +65,7 @@
      *
      * @return route protocol
      */
-    RouteProtocol routeProtocol() {
+    public RouteProtocol routeProtocol() {
         return routeProtocol;
     }
 
@@ -74,7 +74,7 @@
      *
      * @param routeProtocol route protocol
      */
-    void routeProtocol(RouteProtocol routeProtocol) {
+    public void routeProtocol(RouteProtocol routeProtocol) {
         this.routeProtocol = routeProtocol;
     }
 
@@ -83,7 +83,7 @@
      *
      * @return process id
      */
-    String processId() {
+    public String processId() {
         return processId;
     }
 
@@ -92,7 +92,7 @@
      *
      * @param processId process id.
      */
-    void processId(String processId) {
+    public void processId(String processId) {
         this.processId = processId;
     }
 
@@ -102,7 +102,7 @@
      *
      * @return true if IPV4 address family uses; false otherwise
      */
-    boolean isIpv4Af() {
+    public boolean isIpv4Af() {
         return ipv4Af;
     }
 
@@ -112,7 +112,7 @@
      *
      * @param ipv4Af true if IPV4 interface uses; false otherwise
      */
-    void ipv4Af(boolean ipv4Af) {
+    public void ipv4Af(boolean ipv4Af) {
         this.ipv4Af = ipv4Af;
     }
 
@@ -122,7 +122,7 @@
      *
      * @return true if IPV6 address family uses; false otherwise
      */
-    boolean isIpv6Af() {
+    public boolean isIpv6Af() {
         return ipv6Af;
     }
 
@@ -132,7 +132,7 @@
      *
      * @param ipv6Af true if IPV6 interface uses; false otherwise
      */
-    void ipv6Af(boolean ipv6Af) {
+    public void ipv6Af(boolean ipv6Af) {
         this.ipv6Af = ipv6Af;
     }
 
@@ -141,7 +141,7 @@
      *
      * @return IPV4 network accesses
      */
-    List<AccessInfo> v4Accesses() {
+    public List<AccessInfo> v4Accesses() {
         return v4Accesses;
     }
 
@@ -150,7 +150,7 @@
      *
      * @param v4Accesses IPV4 network accesses
      */
-    void v4Accesses(List<AccessInfo> v4Accesses) {
+    public void v4Accesses(List<AccessInfo> v4Accesses) {
         this.v4Accesses = v4Accesses;
     }
 
@@ -159,7 +159,7 @@
      *
      * @param info IPV4 network access
      */
-    void addV4Key(AccessInfo info) {
+    public void addV4Access(AccessInfo info) {
         if (v4Accesses == null) {
             v4Accesses = new LinkedList<>();
         }
@@ -171,7 +171,7 @@
      *
      * @return IPV6 network accesses
      */
-    List<AccessInfo> v6Accesses() {
+    public List<AccessInfo> v6Accesses() {
         return v6Accesses;
     }
 
@@ -180,7 +180,7 @@
      *
      * @param v6Accesses IPV6 network accesses
      */
-    void v6Accesses(List<AccessInfo> v6Accesses) {
+    public void v6Accesses(List<AccessInfo> v6Accesses) {
         this.v4Accesses = v6Accesses;
     }
 
@@ -188,7 +188,7 @@
      * Adds a access info to the IPV6 network accesses.
      * @param info IPV4 network access
      */
-    void addV6Key(AccessInfo info) {
+    public void addV6Access(AccessInfo info) {
         if (v6Accesses == null) {
             v6Accesses = new LinkedList<>();
         }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/RouteProtocol.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/RouteProtocol.java
index 8ff03f6..2bda454 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/RouteProtocol.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/RouteProtocol.java
@@ -75,7 +75,7 @@
      * @param name protocol name
      * @return route protocol
      */
-    static RouteProtocol getProType(String name) {
+    public static RouteProtocol getProType(String name) {
         for (RouteProtocol protocol : values()) {
             if (protocol.proType.equals(name.toLowerCase())) {
                 return protocol;
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnConfig.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnConfig.java
index d9973b0..0b39a43 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnConfig.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnConfig.java
@@ -37,7 +37,7 @@
      *
      * @return RD value
      */
-    String rd() {
+    public String rd() {
         return rd;
     }
 
@@ -46,7 +46,7 @@
      *
      * @param rd RD value
      */
-    void rd(String rd) {
+    public void rd(String rd) {
         this.rd = rd;
     }
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnInstance.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnInstance.java
index b411b87..880ed51 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnInstance.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnInstance.java
@@ -61,7 +61,7 @@
      *
      * @return VPN type
      */
-    VpnType type() {
+    public VpnType type() {
         return type;
     }
 
@@ -70,7 +70,7 @@
      *
      * @param type VPN type
      */
-    void type(VpnType type) {
+    public void type(VpnType type) {
         this.type = type;
     }
 
@@ -79,7 +79,7 @@
      *
      * @return VPN config
      */
-    T vpnConfig() {
+    public T vpnConfig() {
         return vpnConfig;
     }
 
@@ -88,7 +88,7 @@
      *
      * @param vpnConfig VPN config
      */
-    void vpnConfig(T vpnConfig) {
+    public void vpnConfig(T vpnConfig) {
         this.vpnConfig = vpnConfig;
     }
 
@@ -97,7 +97,7 @@
      *
      * @return device info map
      */
-    Map<DeviceId, DeviceInfo> devInfo() {
+    public Map<DeviceId, DeviceInfo> devInfo() {
         return devInfo;
     }
 
@@ -106,7 +106,7 @@
      *
      * @param devInfo device info map
      */
-    void devInfo(Map<DeviceId, DeviceInfo> devInfo) {
+    public void devInfo(Map<DeviceId, DeviceInfo> devInfo) {
         this.devInfo = devInfo;
     }
 
@@ -116,7 +116,7 @@
      * @param id   device id
      * @param info device info
      */
-    void devInfo(DeviceId id, DeviceInfo info) {
+    public void addDevInfo(DeviceId id, DeviceInfo info) {
         if (devInfo == null) {
             devInfo = new LinkedHashMap<>();
         }
@@ -128,7 +128,7 @@
      *
      * @return VPN name
      */
-    String vpnName() {
+    public String vpnName() {
         return vpnName;
     }
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnSiteRole.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnSiteRole.java
index e67018c..062fe56 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnSiteRole.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/VpnSiteRole.java
@@ -48,7 +48,7 @@
      *
      * @return VPN name
      */
-    String name() {
+    public String name() {
         return name;
     }
 
@@ -57,7 +57,7 @@
      *
      * @return site role
      */
-    VpnType role() {
+    public VpnType role() {
         return role;
     }
 }
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/BgpConstructionUtil.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/BgpConstructionUtil.java
new file mode 100644
index 0000000..97ae129
--- /dev/null
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/BgpConstructionUtil.java
@@ -0,0 +1,244 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.l3vpn.netl3vpn.impl;
+
+import org.onosproject.l3vpn.netl3vpn.AccessInfo;
+import org.onosproject.l3vpn.netl3vpn.BgpInfo;
+import org.onosproject.l3vpn.netl3vpn.DeviceInfo;
+import org.onosproject.l3vpn.netl3vpn.NetL3VpnException;
+import org.onosproject.l3vpn.netl3vpn.ProtocolInfo;
+import org.onosproject.l3vpn.netl3vpn.RouteProtocol;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.RoutingProtocolType;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentipconnection.IpConnection;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siterouting.routingprotocols.RoutingProtocol;
+
+import java.util.List;
+import java.util.Map;
+
+import static org.onosproject.l3vpn.netl3vpn.RouteProtocol.DIRECT;
+import static org.onosproject.l3vpn.netl3vpn.RouteProtocol.STATIC;
+import static org.onosproject.l3vpn.netl3vpn.RouteProtocol.getProType;
+
+/**
+ * Representation of utility for BGP info creation and deletion.
+ */
+public final class BgpConstructionUtil {
+
+    private static final String ZERO = "0";
+
+    // No instantiation.
+    private BgpConstructionUtil() {
+    }
+
+    /**
+     * Creates the BGP info instance, from the routing protocols available.
+     * It returns BGP info if for the first time, else returns null.
+     *
+     * @param routes  route protocol
+     * @param info    device info
+     * @param vpnName VPN name
+     * @param connect ip connection
+     * @param access  access info
+     * @return BGP info instance
+     */
+    public static BgpInfo createBgpInfo(List<RoutingProtocol> routes,
+                                        DeviceInfo info, String vpnName,
+                                        IpConnection connect, AccessInfo access) {
+        BgpInfo devBgp = info.bgpInfo();
+        BgpInfo infoBgp = new BgpInfo();
+        infoBgp.vpnName(vpnName);
+        if (devBgp != null) {
+            infoBgp = updateDevBgpInfo(devBgp, infoBgp, connect, routes, access);
+        } else {
+            infoBgp = updateDevBgpInfo(null, infoBgp, connect, routes, access);
+            info.bgpInfo(infoBgp);
+        }
+        if (infoBgp == null || infoBgp.protocolInfo() == null) {
+            return null;
+        }
+        return infoBgp;
+    }
+
+    /**
+     * Updates the device BGP info and also creates the BGP info which has to
+     * be sent to driver, if it is called for the first time.
+     *
+     * @param devBgp  device BGP info
+     * @param driBgp  driver BGP info
+     * @param connect ip connection
+     * @param routes  route protocols
+     * @param access  access info
+     * @return driver BGP info
+     */
+    private static BgpInfo updateDevBgpInfo(BgpInfo devBgp, BgpInfo driBgp,
+                                            IpConnection connect,
+                                            List<RoutingProtocol> routes,
+                                            AccessInfo access) {
+        for (RoutingProtocol route : routes) {
+            ProtocolInfo ifInfo = getRoutePro(route.type(), connect, access);
+            if (ifInfo != null) {
+                if (devBgp != null) {
+                    ProtocolInfo info = addToDevBgp(ifInfo, devBgp, access);
+                    ifInfo = getUpdatedProInfo(info, ifInfo);
+                }
+                if (ifInfo != null) {
+                    driBgp.addProtocolInfo(ifInfo.routeProtocol(), ifInfo);
+                }
+            }
+        }
+        return driBgp;
+    }
+
+    /**
+     * Returns the updated protocol info that has to be sent to driver. If
+     * the protocol info is for the second time or more, the driver info's
+     * protocol info will not be sent. It will return null if no info is
+     * present or nothing to be sent to driver.
+     *
+     * @param devInfo device protocol info
+     * @param driInfo driver protocol info
+     * @return updated driver protocol info
+     */
+    private static ProtocolInfo getUpdatedProInfo(ProtocolInfo devInfo,
+                                                  ProtocolInfo driInfo) {
+        if (driInfo.isIpv4Af() && driInfo.isIpv6Af()) {
+            if ((getV4Size(devInfo) > 1) && (getV6Size(devInfo) > 1)) {
+                return null;
+            }
+            if ((getV4Size(devInfo) > 1) && !(getV6Size(devInfo) > 1)) {
+                driInfo.ipv4Af(false);
+            } else if (!(getV4Size(devInfo) > 1) && (getV6Size(devInfo) > 1)) {
+                driInfo.ipv6Af(false);
+            }
+        }
+        if (driInfo.isIpv4Af() && !driInfo.isIpv6Af()) {
+            if (getV4Size(devInfo) > 1) {
+                return null;
+            }
+        }
+        if (!driInfo.isIpv4Af() && driInfo.isIpv6Af()) {
+            if (getV6Size(devInfo) > 1) {
+                return null;
+            }
+        }
+        return driInfo;
+    }
+
+    private static int getV4Size(ProtocolInfo proInfo) {
+        return proInfo.v4Accesses().size();
+    }
+
+    private static int getV6Size(ProtocolInfo proInfo) {
+        return proInfo.v6Accesses().size();
+    }
+
+    /**
+     * Adds the protocol info to the device BGP info.
+     *
+     * @param proInfo protocol info
+     * @param devBgp  device BGP
+     * @param access  access info
+     * @return protocol info
+     */
+    private static ProtocolInfo addToDevBgp(ProtocolInfo proInfo,
+                                            BgpInfo devBgp, AccessInfo access) {
+        Map<RouteProtocol, ProtocolInfo> devMap = devBgp.protocolInfo();
+        ProtocolInfo devInfo = devMap.get(proInfo.routeProtocol());
+        if (devInfo != null) {
+            if (proInfo.isIpv4Af()) {
+                devInfo.ipv4Af(proInfo.isIpv4Af());
+                devInfo.addV4Access(access);
+            }
+            if (proInfo.isIpv6Af()) {
+                devInfo.ipv6Af(proInfo.isIpv6Af());
+                devInfo.addV6Access(access);
+            }
+        } else {
+            devInfo = proInfo;
+            devBgp.addProtocolInfo(proInfo.routeProtocol(), devInfo);
+        }
+        return devInfo;
+    }
+
+
+    /**
+     * Returns the protocol info of BGP by taking values from the service files.
+     *
+     * @param type    protocol type
+     * @param connect IP connection
+     * @param access  access info
+     * @return protocol info
+     */
+    private static ProtocolInfo getRoutePro(Class<? extends RoutingProtocolType> type,
+                                            IpConnection connect, AccessInfo access) {
+        ProtocolInfo protocolInfo = new ProtocolInfo();
+        RouteProtocol protocol = getProType(type.getSimpleName());
+        switch (protocol) {
+            case DIRECT:
+                protocolInfo.routeProtocol(DIRECT);
+                protocolInfo.processId(ZERO);
+                setAddressFamily(protocolInfo, connect, access);
+                return protocolInfo;
+
+            case STATIC:
+                protocolInfo.routeProtocol(STATIC);
+                protocolInfo.processId(ZERO);
+                setAddressFamily(protocolInfo, connect, access);
+                return protocolInfo;
+
+            case BGP:
+            case OSPF:
+            case RIP:
+            case RIP_NG:
+            case VRRP:
+            default:
+                throw new NetL3VpnException(getRouteProErr(
+                        type.getSimpleName()));
+        }
+    }
+
+    /**
+     * Returns the route protocol error message for unsupported type.
+     *
+     * @param type route protocol type
+     * @return error message
+     */
+    private static String getRouteProErr(String type) {
+        return type + " routing protocol is not supported.";
+    }
+
+    /**
+     * Sets the address family of the protocol info.
+     *
+     * @param proInfo protocol info
+     * @param connect ip connection
+     * @param access  access info
+     */
+    private static void setAddressFamily(ProtocolInfo proInfo,
+                                         IpConnection connect, AccessInfo access) {
+        if (connect.ipv4() != null && connect.ipv4().addresses() != null &&
+                connect.ipv4().addresses().providerAddress() != null) {
+            proInfo.ipv4Af(true);
+            proInfo.addV4Access(access);
+        }
+        if (connect.ipv6() != null && connect.ipv6().addresses() != null &&
+                connect.ipv6().addresses().providerAddress() != null) {
+            proInfo.ipv6Af(true);
+            proInfo.addV6Access(access);
+        }
+    }
+}
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/InsConstructionUtil.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/InsConstructionUtil.java
new file mode 100644
index 0000000..d5ea1a6
--- /dev/null
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/InsConstructionUtil.java
@@ -0,0 +1,240 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.l3vpn.netl3vpn.impl;
+
+import org.onosproject.l3vpn.netl3vpn.FullMeshVpnConfig;
+import org.onosproject.l3vpn.netl3vpn.HubSpokeVpnConfig;
+import org.onosproject.l3vpn.netl3vpn.VpnInstance;
+import org.onosproject.l3vpn.netl3vpn.VpnSiteRole;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.devices.device.networkinstances.networkinstance.AugmentedNiNetworkInstance;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.devices.device.networkinstances.networkinstance.DefaultAugmentedNiNetworkInstance;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.devices.device.networkinstances.networkinstance.augmentedninetworkinstance.DefaultL3Vpn;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.devices.device.networkinstances.networkinstance.augmentedninetworkinstance.L3Vpn;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams.DefaultIpv4;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams.DefaultIpv6;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams.Ipv4;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams.Ipv6;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams.ipv4.DefaultUnicast;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams.ipv4.Unicast;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routedistinguisherparams.DefaultRouteDistinguisher;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routedistinguisherparams.RouteDistinguisher;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetparams.DefaultRouteTargets;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetparams.RouteTargets;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetparams.routetargets.Config;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetparams.routetargets.DefaultConfig;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetset.DefaultRts;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetset.Rts;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetset.rts.RtTypeEnum;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentipconnection.IpConnection;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.DefaultNetworkInstances;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.NetworkInstances;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.networkinstances.DefaultNetworkInstance;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.networkinstances.NetworkInstance;
+
+import java.util.LinkedList;
+import java.util.List;
+
+import static org.onosproject.l3vpn.netl3vpn.VpnType.ANY_TO_ANY;
+import static org.onosproject.l3vpn.netl3vpn.VpnType.HUB;
+import static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetset.rts.RtTypeEnum.BOTH;
+import static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetset.rts.RtTypeEnum.EXPORT;
+import static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.routetargetset.rts.RtTypeEnum.IMPORT;
+
+/**
+ * Representation of utility for instance creation and deletion.
+ */
+public final class InsConstructionUtil {
+
+    // No instantiation.
+    private InsConstructionUtil() {
+    }
+
+    /**
+     * Creates network instance with augmented info such as RD and RT.
+     *
+     * @param vpnIns  VPN instance
+     * @param role    VPN role
+     * @param connect ip connection
+     * @return network instance
+     */
+    public static NetworkInstances createInstance(VpnInstance vpnIns,
+                                                  VpnSiteRole role,
+                                                  IpConnection connect) {
+        NetworkInstance ins = new DefaultNetworkInstance();
+        NetworkInstances instances = new DefaultNetworkInstances();
+        List<NetworkInstance> insList = new LinkedList<>();
+
+        L3Vpn l3Vpn = buildRd(vpnIns);
+        DefaultAugmentedNiNetworkInstance augIns =
+                buildRt(connect, role, l3Vpn, vpnIns);
+        ins.name(vpnIns.vpnName());
+        insList.add(ins);
+        ((DefaultNetworkInstance) ins).addAugmentation(augIns);
+        instances.networkInstance(insList);
+        return instances;
+    }
+
+    /**
+     * Builds RT from l3 VPN according to the address family VPN belongs to.
+     * It returns built aug network instance from l3 VPN.
+     *
+     * @param con   ip connection
+     * @param role  site VPN role
+     * @param l3Vpn l3 VPN
+     * @param ins   VPN instance
+     * @return aug network instance
+     */
+    private static DefaultAugmentedNiNetworkInstance buildRt(IpConnection con,
+                                                             VpnSiteRole role,
+                                                             L3Vpn l3Vpn,
+                                                             VpnInstance ins) {
+        Ipv4 ipv4 = null;
+        Ipv6 ipv6 = null;
+        if (con.ipv4() != null && con.ipv4().addresses()
+                .providerAddress() != null) {
+            ipv4 = buildIpv4Rt(role, ins);
+        }
+        if (con.ipv6() != null && con.ipv6()
+                .addresses().providerAddress() != null) {
+            ipv6 = buildIpv6Rt(role, ins);
+        }
+        l3Vpn.ipv4(ipv4);
+        l3Vpn.ipv6(ipv6);
+
+        AugmentedNiNetworkInstance augInst =
+                new DefaultAugmentedNiNetworkInstance();
+        augInst.l3Vpn(l3Vpn);
+        return (DefaultAugmentedNiNetworkInstance) augInst;
+    }
+
+    /**
+     * Builds ipv6 RT in the device model.
+     *
+     * @param role   site VPN role
+     * @param vpnIns VPN instance
+     * @return ipv6
+     */
+    private static Ipv6 buildIpv6Rt(VpnSiteRole role, VpnInstance vpnIns) {
+        RouteTargets rts6 = new DefaultRouteTargets();
+        Ipv6 v6 = new DefaultIpv6();
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn
+                .rev20160909.ietfbgpl3vpn.l3vpnvrfparams.ipv6.Unicast uni6 =
+                new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang
+                        .ietf.bgp.l3vpn.rev20160909.ietfbgpl3vpn.l3vpnvrfparams
+                        .ipv6.DefaultUnicast();
+
+        Config configV6 = configRouteTarget(vpnIns, role);
+        rts6.config(configV6);
+        uni6.routeTargets(rts6);
+        v6.unicast(uni6);
+        return v6;
+    }
+
+    /**
+     * Builds ipv4 RT in the device model.
+     *
+     * @param role   site VPN role
+     * @param vpnIns VPN instance
+     * @return ipv4
+     */
+    private static Ipv4 buildIpv4Rt(VpnSiteRole role, VpnInstance vpnIns) {
+        RouteTargets rts4 = new DefaultRouteTargets();
+        Unicast uni4 = new DefaultUnicast();
+        Ipv4 v4 = new DefaultIpv4();
+
+        Config configV4 = configRouteTarget(vpnIns, role);
+        rts4.config(configV4);
+        uni4.routeTargets(rts4);
+        v4.unicast(uni4);
+        return v4;
+    }
+
+    /**
+     * Configures route target according to the site VPN role from the stored
+     * VPN instance.
+     *
+     * @param ins  VPN instance
+     * @param role site VPN role
+     * @return route target config
+     */
+    private static Config configRouteTarget(VpnInstance ins,
+                                            VpnSiteRole role) {
+        Rts rts1;
+        Config config = new DefaultConfig();
+        List<Rts> rtsList = new LinkedList<>();
+
+        if (ins.type() == ANY_TO_ANY) {
+            String rtVal = ((FullMeshVpnConfig) ins.vpnConfig()).rt();
+            rts1 = getRtsVal(rtVal, BOTH);
+        } else {
+            String rtVal1;
+            String rtVal2;
+            HubSpokeVpnConfig conf = (HubSpokeVpnConfig) ins.vpnConfig();
+            if (role.role() == HUB) {
+                rtVal1 = conf.hubImpRt();
+                rtVal2 = conf.hubExpRt();
+            } else {
+                rtVal1 = conf.spokeImpRt();
+                rtVal2 = conf.spokeExpRt();
+            }
+            rts1 = getRtsVal(rtVal1, IMPORT);
+            Rts rts2 = getRtsVal(rtVal2, EXPORT);
+            rtsList.add(rts2);
+        }
+        rtsList.add(rts1);
+        config.rts(rtsList);
+        return config;
+    }
+
+    /**
+     * Returns the device model RT from the RT type and RT value after
+     * building it.
+     *
+     * @param rtVal RT value
+     * @param type  RT type
+     * @return device model RT
+     */
+    private static Rts getRtsVal(String rtVal, RtTypeEnum type) {
+        Rts rts = new DefaultRts();
+        rts.rt(rtVal);
+        rts.rtType(type);
+        return rts;
+    }
+
+    /**
+     * Builds RD from the stored device model VPN instance.
+     *
+     * @param vpn VPN instance
+     * @return l3 VPN object
+     */
+    private static L3Vpn buildRd(VpnInstance vpn) {
+
+        String rd = vpn.vpnConfig().rd();
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn
+                .rev20160909.ietfbgpl3vpn.routedistinguisherparams
+                .routedistinguisher.Config config = new org.onosproject.yang
+                .gen.v1.urn.ietf.params.xml.ns.yang.ietf.bgp.l3vpn.rev20160909
+                .ietfbgpl3vpn.routedistinguisherparams.routedistinguisher
+                .DefaultConfig();
+        config.rd(rd);
+        RouteDistinguisher dist = new DefaultRouteDistinguisher();
+        dist.config(config);
+        L3Vpn l3vpn = new DefaultL3Vpn();
+        l3vpn.routeDistinguisher(dist);
+        return l3vpn;
+    }
+}
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/IntConstructionUtil.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/IntConstructionUtil.java
new file mode 100644
index 0000000..f087859
--- /dev/null
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/IntConstructionUtil.java
@@ -0,0 +1,199 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.l3vpn.netl3vpn.impl;
+
+import org.onosproject.l3vpn.netl3vpn.NetL3VpnException;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev20130715.ietfinettypes.Ipv4Address;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev20130715.ietfinettypes.Ipv4AddressNoZone;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev20130715.ietfinettypes.Ipv6Address;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev20130715.ietfinettypes.Ipv6AddressNoZone;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev20140508.ietfinterfaces.devices.device.DefaultInterfaces;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev20140508.ietfinterfaces.devices.device.Interfaces;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev20140508.ietfinterfaces.devices.device.interfaces.DefaultYangAutoPrefixInterface;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev20140508.ietfinterfaces.devices.device.interfaces.YangAutoPrefixInterface;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.AugmentedIfInterface;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.DefaultAugmentedIfInterface;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.DefaultIpv4;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.DefaultIpv6;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.Ipv4;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.Ipv6;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.ipv4.Address;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.ipv4.DefaultAddress;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.ipv4.address.Subnet;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip.rev20140616.ietfip.devices.device.interfaces.yangautoprefixinterface.augmentedifinterface.ipv4.address.subnet.DefaultPrefixLength;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentipconnection.IpConnection;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.interfaces.yangautoprefixinterface.ipv4.AugmentedIpIpv4;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.interfaces.yangautoprefixinterface.ipv4.DefaultAugmentedIpIpv4;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.interfaces.yangautoprefixinterface.ipv6.AugmentedIpIpv6;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.interfaces.yangautoprefixinterface.ipv6.DefaultAugmentedIpIpv6;
+import org.onosproject.yang.model.InnerModelObject;
+
+import java.util.LinkedList;
+import java.util.List;
+
+/**
+ * Representation of utility for interface creation and deletion.
+ */
+public final class IntConstructionUtil {
+
+    private static final String IP_ADD_NULL = "Vpn binding to an interface " +
+            "requires ip address.";
+
+    // No instantiation.
+    private IntConstructionUtil() {
+    }
+
+    /**
+     * Creates device model interface by building its parameters with port
+     * name, VPN name and ip connection.
+     *
+     * @param pName   port name
+     * @param vpnName VPN name
+     * @param connect ip connection
+     * @return interface device model
+     */
+    public static Interfaces createInterface(String pName, String vpnName,
+                                             IpConnection connect) {
+        Interfaces interfaces = new DefaultInterfaces();
+        List<YangAutoPrefixInterface> intList = new LinkedList<>();
+        YangAutoPrefixInterface inter = buildInterface(vpnName, pName, connect);
+        intList.add(inter);
+        interfaces.yangAutoPrefixInterface(intList);
+        return interfaces;
+    }
+
+    /**
+     * Builds augmented info of ip address to the interface.
+     *
+     * @param vpnName VPN name
+     * @param pName   port name
+     * @param connect ip connection
+     * @return interface
+     */
+    private static YangAutoPrefixInterface buildInterface(String vpnName,
+                                                          String pName,
+                                                          IpConnection connect) {
+        // Bind vpn name in the augmented info of interface.
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network
+                .instance.rev20160623.ietfnetworkinstance.devices.device
+                .interfaces.yangautoprefixinterface.AugmentedIfInterface augIf =
+                new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang
+                        .ietf.network.instance.rev20160623.ietfnetworkinstance
+                        .devices.device.interfaces.yangautoprefixinterface
+                        .DefaultAugmentedIfInterface();
+        augIf.bindNetworkInstanceName(vpnName);
+
+        // Bind ip address to the interface as augmented info.
+        AugmentedIfInterface intAug = buildIpAddress(connect, vpnName);
+        YangAutoPrefixInterface inter = new DefaultYangAutoPrefixInterface();
+        inter.name(pName);
+        ((DefaultYangAutoPrefixInterface) inter).addAugmentation(
+                (InnerModelObject) augIf);
+        ((DefaultYangAutoPrefixInterface) inter).addAugmentation(
+                (InnerModelObject) intAug);
+
+        return inter;
+    }
+
+    /**
+     * Returns ipv6 address filled with attached VPN, ipv6 address and mask.
+     *
+     * @param vpnName VPN name
+     * @param mask    mask
+     * @param ipv6Add ipv6 address
+     * @return device ipv6 address
+     */
+    private static Ipv6 getIpv6Aug(String vpnName, short mask, String ipv6Add) {
+        AugmentedIpIpv6 augIpv6 = new DefaultAugmentedIpIpv6();
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip
+                .rev20140616.ietfip.devices.device.interfaces
+                .yangautoprefixinterface.augmentedifinterface.ipv6.Address add =
+                new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf
+                        .ip.rev20140616.ietfip.devices.device.interfaces
+                        .yangautoprefixinterface.augmentedifinterface.ipv6
+                        .DefaultAddress();
+        Ipv6 ipv6 = new DefaultIpv6();
+        List<org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.ip
+                .rev20140616.ietfip.devices.device.interfaces
+                .yangautoprefixinterface.augmentedifinterface.ipv6
+                .Address> addList = new LinkedList<>();
+        add.ip(Ipv6AddressNoZone.of(Ipv6Address.of(ipv6Add)));
+        augIpv6.bindNetworkInstanceName(vpnName);
+        add.prefixLength(mask);
+        addList.add(add);
+        ipv6.address(addList);
+        ((DefaultIpv6) ipv6).addAugmentation((DefaultAugmentedIpIpv6) augIpv6);
+        return ipv6;
+    }
+
+    /**
+     * Returns ipv4 address filled with attached VPN, ipv4 address and mask.
+     *
+     * @param vpnName VPN name
+     * @param mask    mask
+     * @param ipv4Add ipv4 address
+     * @return device ipv4 address
+     */
+    private static Ipv4 getIpv4Aug(String vpnName, short mask, String ipv4Add) {
+        AugmentedIpIpv4 augIpv4 = new DefaultAugmentedIpIpv4();
+        Subnet net = new DefaultPrefixLength();
+        Address add = new DefaultAddress();
+        Ipv4 ipv4 = new DefaultIpv4();
+        List<Address> addList = new LinkedList<>();
+
+        augIpv4.bindNetworkInstanceName(vpnName);
+        ((DefaultPrefixLength) net).prefixLength(mask);
+        add.ip(Ipv4AddressNoZone.of(Ipv4Address.of(ipv4Add)));
+        add.subnet(net);
+        addList.add(add);
+        ipv4.address(addList);
+        ((DefaultIpv4) ipv4).addAugmentation((DefaultAugmentedIpIpv4) augIpv4);
+        return ipv4;
+    }
+
+    /**
+     * Builds ip address according to the existence of ip address in ip
+     * connection of device model.
+     *
+     * @param connect ip connection
+     * @param vpnName VPN name
+     * @return augmented interface
+     */
+    public static AugmentedIfInterface buildIpAddress(IpConnection connect,
+                                                      String vpnName) {
+        if (connect == null || (connect.ipv4() == null
+                && connect.ipv6() == null)) {
+            throw new NetL3VpnException(IP_ADD_NULL);
+        }
+        AugmentedIfInterface intAug = new DefaultAugmentedIfInterface();
+        short mask;
+        if (connect.ipv4() != null) {
+            mask = connect.ipv4().addresses().mask();
+            Ipv4Address peIpv4 = connect.ipv4().addresses().providerAddress();
+            Ipv4 v4 = getIpv4Aug(vpnName, mask, peIpv4.string());
+            intAug.ipv4(v4);
+        }
+
+        if (connect.ipv6() != null) {
+            mask = connect.ipv6().addresses().mask();
+            Ipv6Address peIpv6 = connect.ipv6().addresses().providerAddress();
+            Ipv6 v6 = getIpv6Aug(vpnName, mask, peIpv6.string());
+            intAug.ipv6(v6);
+        }
+        return intAug;
+    }
+}
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnUtil.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnUtil.java
new file mode 100644
index 0000000..11674e4
--- /dev/null
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3VpnUtil.java
@@ -0,0 +1,451 @@
+/*
+ * Copyright 2017-present Open Networking Laboratory
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.onosproject.l3vpn.netl3vpn.impl;
+
+import org.onosproject.l3vpn.netl3vpn.AccessInfo;
+import org.onosproject.l3vpn.netl3vpn.BgpDriverInfo;
+import org.onosproject.l3vpn.netl3vpn.BgpInfo;
+import org.onosproject.l3vpn.netl3vpn.InterfaceInfo;
+import org.onosproject.l3vpn.netl3vpn.NetL3VpnException;
+import org.onosproject.l3vpn.netl3vpn.VpnType;
+import org.onosproject.net.DeviceId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev20140508.ietfinterfaces.devices.device.Interfaces;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.DefaultL3VpnSvc;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.SiteRole;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.DefaultSites;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.DefaultDevices;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.Devices;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.DefaultDevice;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.Device;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.DeviceKeys;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.NetworkInstances;
+import org.onosproject.yang.model.DataNode;
+import org.onosproject.yang.model.DefaultModelObjectData;
+import org.onosproject.yang.model.InnerModelObject;
+import org.onosproject.yang.model.ModelObjectData;
+import org.onosproject.yang.model.ModelObjectId;
+import org.onosproject.yang.model.ResourceData;
+import org.onosproject.yang.model.ResourceId;
+import org.onosproject.yang.runtime.DefaultResourceData;
+
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+
+import static org.onosproject.l3vpn.netl3vpn.BgpModelIdLevel.DEVICE;
+import static org.onosproject.l3vpn.netl3vpn.BgpModelIdLevel.DEVICES;
+import static org.onosproject.l3vpn.netl3vpn.BgpModelIdLevel.ROOT;
+import static org.onosproject.l3vpn.netl3vpn.VpnType.ANY_TO_ANY;
+import static org.onosproject.l3vpn.netl3vpn.VpnType.HUB;
+import static org.onosproject.l3vpn.netl3vpn.VpnType.SPOKE;
+
+/**
+ * Representation of utility for YANG tree builder.
+ */
+public final class NetL3VpnUtil {
+
+    /**
+     * Error message for unsupported event from config store.
+     */
+    static final String EVENT_NOT_SUPPORTED = "Unsupported config event has " +
+            "come";
+
+    /**
+     * Error message for site VPN name being not present in global VPN.
+     */
+    static final String SITE_VPN_MISMATCH = "Site VPN instance name did not " +
+            "match any of the global VPN names";
+
+    /**
+     * Error message for VPN attachment object being null.
+     */
+    static final String VPN_ATTACHMENT_NULL = "The VPN attachment information" +
+            " cannot be null";
+
+    /**
+     * Error message for VPN policy being not supported.
+     */
+    static final String VPN_POLICY_NOT_SUPPORTED = "VPN policy implementation" +
+            " is not supported.";
+
+    /**
+     * Static constant value for hundred.
+     */
+    static final String CONS_HUNDRED = "100:";
+
+    /**
+     * Error message for site role being not present in site network access.
+     */
+    static final String SITE_ROLE_NULL = "There must be a site role available" +
+            " for the VPN in site network access.";
+
+    /**
+     * Error message for bearer object information being null.
+     */
+    static final String BEARER_NULL = "The bearer information of the access " +
+            "is not available";
+
+    /**
+     * Error message for requested type or ip connect being null.
+     */
+    static final String IP_INT_INFO_NULL = "The required information of " +
+            "request type or ip connection is not available";
+
+    /**
+     * Error message for device info being not available from augment.
+     */
+    static final String DEVICE_INFO_NULL = "Bearer of site does not have any " +
+            "device information in the augment info.";
+
+    /**
+     * Static constant value for management address.
+     */
+    static final String MG_MT_ADD = "managementAddress";
+
+    /**
+     * Error message for VPN type being not supported.
+     */
+    static final String VPN_TYPE_UNSUPPORTED = "The VPN type is not supported";
+
+    /**
+     * Error message when the generated ID has crossed the limit.
+     */
+    static final String ID_LIMIT_EXCEEDED = "The ID generation has got " +
+            "exceeded";
+
+    /**
+     * Static constant value ID management limit.
+     */
+    static final Long ID_LIMIT = 4294967295L;
+
+    /**
+     * Error message for interface information being not available.
+     */
+    static final String INT_INFO_NULL = "Requested type does not have any " +
+            "interface information in the augment info.";
+
+    /**
+     * Static constant value of port name.
+     */
+    static final String PORT_NAME = "portName";
+
+    private static final String SITE_ROLE_INVALID = "The given site role is " +
+            "invalid";
+    private static final String ANY_TO_ANY_ROLE = "AnyToAnyRole";
+    private static final String HUB_ROLE = "HubRole";
+    private static final String SPOKE_ROLE = "SpokeRole";
+
+    // No instantiation.
+    private NetL3VpnUtil() {
+    }
+
+    /**
+     * Returns the model object id for service L3VPN container.
+     *
+     * @return model object id
+     */
+    static ModelObjectId getModIdForL3VpnSvc() {
+        return ModelObjectId.builder().addChild(DefaultL3VpnSvc.class).build();
+    }
+
+    /**
+     * Returns the model object id for service sites container.
+     *
+     * @return model object id
+     */
+    static ModelObjectId getModIdForSites() {
+        return ModelObjectId.builder().addChild(DefaultL3VpnSvc.class)
+                .addChild(DefaultSites.class).build();
+    }
+
+    /**
+     * Returns the resource data from the data node and the resource id.
+     *
+     * @param dataNode data node
+     * @param resId    resource id
+     * @return resource data
+     */
+    static ResourceData getResourceData(DataNode dataNode, ResourceId resId) {
+        return DefaultResourceData.builder().addDataNode(dataNode)
+                .resourceId(resId).build();
+    }
+
+    /**
+     * Returns the VPN role from the service site role.
+     *
+     * @param siteRole service site role
+     * @return VPN type
+     */
+    static VpnType getRole(Class<? extends SiteRole> siteRole) {
+        switch (siteRole.getSimpleName()) {
+            case ANY_TO_ANY_ROLE:
+                return ANY_TO_ANY;
+
+            case HUB_ROLE:
+                return HUB;
+
+            case SPOKE_ROLE:
+                return SPOKE;
+
+            default:
+                throw new NetL3VpnException(SITE_ROLE_INVALID);
+        }
+    }
+
+    /**
+     * Returns error message for management ip being unavailable in device.
+     *
+     * @param ip management ip
+     * @return error message
+     */
+    static String getMgmtIpUnAvailErr(String ip) {
+        return "The device with management ip " + ip + " is not available.";
+    }
+
+    /**
+     * Returns true if device id present in the interface map; false otherwise.
+     *
+     * @param info interface map
+     * @param id   device id
+     * @return true if device id available; false otherwise
+     */
+    private static boolean isDevIdPresent(Map<AccessInfo, InterfaceInfo> info,
+                                          String id) {
+        for (Map.Entry<AccessInfo, InterfaceInfo> inter : info.entrySet()) {
+            InterfaceInfo interfaceInfo = inter.getValue();
+            DeviceId devId = interfaceInfo.devInfo().deviceId();
+            if (devId.toString().equals(id)) {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * Builds the device model VPN instance model object data, with respect to
+     * the device level.
+     *
+     * @param id  device id
+     * @param ins VPN instance
+     * @return model object data, with device level
+     */
+    private static ModelObjectData buildInsModDataDevice(String id,
+                                                         NetworkInstances ins) {
+        DeviceKeys devKeys = new DeviceKeys();
+        devKeys.deviceid(id);
+        ModelObjectId modelId = ModelObjectId.builder()
+                .addChild(DefaultDevices.class)
+                .addChild(DefaultDevice.class, devKeys)
+                .build();
+        return DefaultModelObjectData.builder().identifer(modelId)
+                .addModelObject((InnerModelObject) ins).build();
+    }
+
+    /**
+     * Builds the device model VPN instance model object data, with respect to
+     * the devices level.
+     *
+     * @param id  device id
+     * @param ins VPN instance
+     * @return model object data, with devices level
+     */
+    private static ModelObjectData buildInsModDataDevices(String id,
+                                                          NetworkInstances ins) {
+        ModelObjectId modelId = ModelObjectId.builder()
+                .addChild(DefaultDevices.class).build();
+        Device device = new DefaultDevice();
+        device.deviceid(id);
+        device.networkInstances(ins);
+        return DefaultModelObjectData.builder().identifer(modelId)
+                .addModelObject((InnerModelObject) device).build();
+    }
+
+    /**
+     * Builds the device model VPN instance model object data, with respect to
+     * root level.
+     *
+     * @param id  device id
+     * @param ins VPN instance
+     * @return model object data, with root level
+     */
+    private static ModelObjectData buildInsModDataRoot(String id,
+                                                       NetworkInstances ins) {
+        Devices devices = new DefaultDevices();
+        Device device = new DefaultDevice();
+        List<Device> deviceList = new LinkedList<>();
+        device.deviceid(id);
+        device.networkInstances(ins);
+        deviceList.add(device);
+        devices.device(deviceList);
+        return DefaultModelObjectData.builder()
+                .addModelObject((InnerModelObject) devices).build();
+    }
+
+    /**
+     * Builds the device model interface model object data, with respect to
+     * device level.
+     *
+     * @param id  device id
+     * @param ifs interface object
+     * @return model object data, with device level
+     */
+    private static ModelObjectData buildIntModDataDevice(String id,
+                                                         Interfaces ifs) {
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces
+                .rev20140508.ietfinterfaces.devices.DeviceKeys keys =
+                new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang
+                        .ietf.interfaces.rev20140508.ietfinterfaces.devices
+                        .DeviceKeys();
+        keys.deviceid(id);
+        ModelObjectId modelId = ModelObjectId.builder()
+                .addChild(org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns
+                                  .yang.ietf.interfaces.rev20140508
+                                  .ietfinterfaces.DefaultDevices.class)
+                .addChild(org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns
+                                  .yang.ietf.interfaces.rev20140508
+                                  .ietfinterfaces.devices.DefaultDevice.class,
+                          keys)
+                .build();
+        return DefaultModelObjectData.builder().identifer(modelId)
+                .addModelObject((InnerModelObject) ifs).build();
+    }
+
+    /**
+     * Returns the VPN instance create model object data.
+     *
+     * @param intMap    interface map
+     * @param instances VPN instances
+     * @param id        device id
+     * @return VPN instance model object data
+     */
+    static ModelObjectData getVpnCreateModObj(Map<AccessInfo, InterfaceInfo> intMap,
+                                              NetworkInstances instances,
+                                              String id) {
+        ModelObjectData modData;
+        boolean devAdded = isDevIdPresent(intMap, id);
+        if (devAdded) {
+            modData = buildInsModDataDevice(id, instances);
+        } else if (intMap.size() != 0) {
+            modData = buildInsModDataDevices(id, instances);
+        } else {
+            modData = buildInsModDataRoot(id, instances);
+        }
+        return modData;
+    }
+
+    /**
+     * Returns error message for interface being unavailable in device.
+     *
+     * @param intName interface name
+     * @return error message
+     */
+    static String getIntNotAvailable(String intName) {
+        return "The interface " + intName + " is not available.";
+    }
+
+    /**
+     * Returns the interface create model object data.
+     *
+     * @param intMap interface map
+     * @param ifs    interface instance
+     * @param id     device id
+     * @return interface model object data
+     */
+    static ModelObjectData getIntCreateModObj(Map<AccessInfo, InterfaceInfo> intMap,
+                                              Interfaces ifs, String id) {
+        ModelObjectData modData;
+        boolean intAdded = isDevIdPresent(intMap, id);
+        if (intAdded) {
+            modData = buildIntModDataDevice(id, ifs);
+        } else {
+            modData = buildIntModDataRoot(id, ifs);
+        }
+        return modData;
+    }
+
+    /**
+     * Builds the device model interface model object data, with respect to
+     * root level.
+     *
+     * @param id  device id
+     * @param ifs interface object
+     * @return model object data, with root level
+     */
+    private static ModelObjectData buildIntModDataRoot(String id,
+                                                       Interfaces ifs) {
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces
+                .rev20140508.ietfinterfaces.Devices devices =
+                new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang
+                        .ietf.interfaces.rev20140508.ietfinterfaces
+                        .DefaultDevices();
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces
+                .rev20140508.ietfinterfaces.devices.Device device =
+                new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang
+                        .ietf.interfaces.rev20140508.ietfinterfaces.devices
+                        .DefaultDevice();
+        List<org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf
+                .interfaces.rev20140508.ietfinterfaces.devices
+                .Device> deviceList = new LinkedList<>();
+
+        device.deviceid(id);
+        device.interfaces(ifs);
+        deviceList.add(device);
+        devices.device(deviceList);
+        return DefaultModelObjectData.builder()
+                .addModelObject((InnerModelObject) devices).build();
+    }
+
+    /**
+     * Returns the BGP create driver info.
+     *
+     * @param bgpMap BGP map
+     * @param id     device id
+     * @return driver config info
+     */
+    static BgpDriverInfo getBgpCreateConfigObj(Map<BgpInfo, DeviceId> bgpMap,
+                                               String id) {
+        boolean isDevIdPresent = isDevIdBgpPresent(bgpMap, id);
+        BgpDriverInfo info;
+        if (isDevIdPresent) {
+            info = new BgpDriverInfo(DEVICE, id);
+
+        } else if (bgpMap.size() != 0) {
+            info = new BgpDriverInfo(DEVICES, id);
+        } else {
+            info = new BgpDriverInfo(ROOT, id);
+        }
+        return info;
+    }
+
+    /**
+     * Returns true if the device is present in the BGP map; false otherwise.
+     *
+     * @param bgpMap BGP map
+     * @param id     device id
+     * @return true if device is present; false otherwise
+     */
+    private static boolean isDevIdBgpPresent(Map<BgpInfo, DeviceId> bgpMap,
+                                             String id) {
+        for (Map.Entry<BgpInfo, DeviceId> info : bgpMap.entrySet()) {
+            DeviceId devId = info.getValue();
+            if (devId.toString().equals(id)) {
+                return true;
+            }
+        }
+        return false;
+    }
+}
diff --git a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3vpnManager.java b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3vpnManager.java
index 107440c..4ccf0a1 100644
--- a/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3vpnManager.java
+++ b/apps/l3vpn/netl3vpn/src/main/java/org/onosproject/l3vpn/netl3vpn/impl/NetL3vpnManager.java
@@ -13,7 +13,6 @@
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */
-
 package org.onosproject.l3vpn.netl3vpn.impl;
 
 import org.apache.felix.scr.annotations.Activate;
@@ -21,11 +20,67 @@
 import org.apache.felix.scr.annotations.Deactivate;
 import org.apache.felix.scr.annotations.Reference;
 import org.apache.felix.scr.annotations.ReferenceCardinality;
+import org.onosproject.config.DynamicConfigEvent;
+import org.onosproject.config.DynamicConfigListener;
+import org.onosproject.config.DynamicConfigService;
 import org.onosproject.core.CoreService;
+import org.onosproject.core.IdGenerator;
+import org.onosproject.l3vpn.netl3vpn.AccessInfo;
+import org.onosproject.l3vpn.netl3vpn.BgpDriverInfo;
+import org.onosproject.l3vpn.netl3vpn.BgpInfo;
+import org.onosproject.l3vpn.netl3vpn.DeviceInfo;
+import org.onosproject.l3vpn.netl3vpn.FullMeshVpnConfig;
+import org.onosproject.l3vpn.netl3vpn.HubSpokeVpnConfig;
+import org.onosproject.l3vpn.netl3vpn.InterfaceInfo;
+import org.onosproject.l3vpn.netl3vpn.NetL3VpnException;
+import org.onosproject.l3vpn.netl3vpn.NetL3VpnStore;
+import org.onosproject.l3vpn.netl3vpn.VpnConfig;
+import org.onosproject.l3vpn.netl3vpn.VpnInstance;
+import org.onosproject.l3vpn.netl3vpn.VpnSiteRole;
+import org.onosproject.l3vpn.netl3vpn.VpnType;
+import org.onosproject.net.Device;
+import org.onosproject.net.DeviceId;
+import org.onosproject.net.Port;
+import org.onosproject.net.device.DeviceService;
+import org.onosproject.net.driver.DriverService;
 import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.inet.types.rev20130715.IetfInetTypes;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.interfaces.rev20140508.ietfinterfaces.devices.device.Interfaces;
 import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.IetfL3VpnSvc;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.DefaultL3VpnSvc;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.L3VpnSvc;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.accessvpnpolicy.VpnAttachment;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.accessvpnpolicy.vpnattachment.AttachmentFlavor;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.accessvpnpolicy.vpnattachment.attachmentflavor.DefaultVpnId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.Sites;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.VpnServices;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.sites.Site;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.sites.site.SiteNetworkAccesses;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.sites.site.sitenetworkaccesses.SiteNetworkAccess;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.l3vpnsvc.vpnservices.VpnSvc;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentbearer.Bearer;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentbearer.DefaultBearer;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentbearer.bearer.DefaultRequestedType;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentbearer.bearer.RequestedType;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siteattachmentipconnection.IpConnection;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siterouting.RoutingProtocols;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.l3vpn.svc.rev20160730.ietfl3vpnsvc.siterouting.routingprotocols.RoutingProtocol;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.instance.rev20160623.ietfnetworkinstance.devices.device.NetworkInstances;
 import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.yang.types.rev20130715.IetfYangTypes;
 import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.l3vpn.svc.ext.rev20160730.L3VpnSvcExt;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.l3vpn.svc.ext.rev20160730.l3vpnsvcext.l3vpnsvc.sites.site.sitenetworkaccesses.sitenetworkaccess.bearer.DefaultAugmentedL3VpnBearer;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.l3vpn.svc.ext.rev20160730.l3vpnsvcext.l3vpnsvc.sites.site.sitenetworkaccesses.sitenetworkaccess.bearer.requestedtype.DefaultAugmentedL3VpnRequestedType;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.l3vpn.svc.ext.rev20160730.l3vpnsvcext.requestedtypegrouping.requestedtypeprofile.RequestedTypeChoice;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.l3vpn.svc.ext.rev20160730.l3vpnsvcext.requestedtypegrouping.requestedtypeprofile.requestedtypechoice.DefaultDot1Qcase;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.l3vpn.svc.ext.rev20160730.l3vpnsvcext.requestedtypegrouping.requestedtypeprofile.requestedtypechoice.DefaultPhysicalCase;
+import org.onosproject.yang.model.DataNode;
+import org.onosproject.yang.model.DefaultModelObjectData;
+import org.onosproject.yang.model.ModelConverter;
+import org.onosproject.yang.model.ModelObject;
+import org.onosproject.yang.model.ModelObjectData;
+import org.onosproject.yang.model.ModelObjectId;
+import org.onosproject.yang.model.NodeKey;
+import org.onosproject.yang.model.ResourceData;
+import org.onosproject.yang.model.ResourceId;
 import org.onosproject.yang.model.YangModel;
 import org.onosproject.yang.model.YangModuleId;
 import org.onosproject.yang.runtime.DefaultAppModuleInfo;
@@ -36,7 +91,42 @@
 import org.slf4j.LoggerFactory;
 
 import java.util.Iterator;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Executors;
 
+import static org.onlab.util.Tools.groupedThreads;
+import static org.onosproject.config.DynamicConfigEvent.Type.NODE_ADDED;
+import static org.onosproject.config.DynamicConfigEvent.Type.NODE_DELETED;
+import static org.onosproject.l3vpn.netl3vpn.impl.BgpConstructionUtil.createBgpInfo;
+import static org.onosproject.l3vpn.netl3vpn.impl.InsConstructionUtil.createInstance;
+import static org.onosproject.l3vpn.netl3vpn.impl.IntConstructionUtil.createInterface;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.BEARER_NULL;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.CONS_HUNDRED;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.DEVICE_INFO_NULL;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.EVENT_NOT_SUPPORTED;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.ID_LIMIT;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.ID_LIMIT_EXCEEDED;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.INT_INFO_NULL;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.IP_INT_INFO_NULL;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.MG_MT_ADD;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.PORT_NAME;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.SITE_ROLE_NULL;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.SITE_VPN_MISMATCH;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.VPN_ATTACHMENT_NULL;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.VPN_POLICY_NOT_SUPPORTED;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.VPN_TYPE_UNSUPPORTED;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getBgpCreateConfigObj;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getIntCreateModObj;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getIntNotAvailable;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getMgmtIpUnAvailErr;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getModIdForL3VpnSvc;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getModIdForSites;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getResourceData;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getRole;
+import static org.onosproject.l3vpn.netl3vpn.impl.NetL3VpnUtil.getVpnCreateModObj;
+import static org.onosproject.l3vpn.netl3vpn.VpnType.HUB;
 import static org.onosproject.yang.runtime.helperutils.YangApacheUtils.getYangModel;
 
 /**
@@ -47,26 +137,60 @@
 public class NetL3vpnManager {
 
     private static final String APP_ID = "org.onosproject.app.l3vpn";
+    private static final String L3_VPN_ID_TOPIC = "l3vpn-id";
+    private static final String ONOS_NET_L3VPN = "onos/netl3vpn";
+    private static final String EVENT_HANDLER = "event-handler-%d";
+
     private final Logger log = LoggerFactory.getLogger(getClass());
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected CoreService coreService;
 
     @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DriverService driverService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DeviceService deviceService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
     protected YangModelRegistry modelRegistry;
 
-    private ModelRegistrationParam regParam = null;
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected ModelConverter modelConverter;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected DynamicConfigService configService;
+
+    @Reference(cardinality = ReferenceCardinality.MANDATORY_UNARY)
+    protected NetL3VpnStore l3VpnStore;
+
+    protected IdGenerator l3VpnIdGen;
+
+    private DynamicConfigListener configListener = new InternalConfigListener();
+
+    private ModelRegistrationParam regParam;
+
+    private ExecutorService executor = Executors.newSingleThreadExecutor(
+            groupedThreads(ONOS_NET_L3VPN, EVENT_HANDLER, log));
+
+    private ResourceId id;
+    private ResourceId module;
+    private ResourceId sites;
 
     @Activate
     protected void activate() {
         coreService.registerApplication(APP_ID);
+        l3VpnIdGen = coreService.getIdGenerator(L3_VPN_ID_TOPIC);
+        registerModel();
+        getResourceId();
+        configService.addListener(configListener);
         log.info("Started");
-        //TODO implementation
     }
 
     @Deactivate
     protected void deactivate() {
         modelRegistry.unregisterModel(regParam);
+        configService.removeListener(configListener);
         log.info("Stopped");
     }
 
@@ -105,4 +229,638 @@
         regParam = b.build();
         modelRegistry.registerModel(regParam);
     }
+
+    /**
+     * Returns id as string. If the id is not in the freed list a new id is
+     * generated else the id from the freed list is used.
+     *
+     * @return id
+     */
+    private String getIdFromGen() {
+        Long value;
+        Iterable<Long> freeIds = l3VpnStore.getFreedIdList();
+        Iterator<Long> it = freeIds.iterator();
+        if (it.hasNext()) {
+            value = it.next();
+            l3VpnStore.removeIdFromFreeList(value);
+        } else {
+            value = l3VpnIdGen.getNewId();
+        }
+        if (value > ID_LIMIT) {
+            throw new RuntimeException(ID_LIMIT_EXCEEDED);
+        }
+        return CONS_HUNDRED + String.valueOf(value);
+    }
+
+    /**
+     * Returns the resource id, after constructing model object id and
+     * converting it.
+     */
+    private void getResourceId() {
+
+        ModelObjectId moduleId = ModelObjectId.builder().build();
+        module = getResourceVal(moduleId);
+
+        ModelObjectId svcId = getModIdForL3VpnSvc();
+        id = getResourceVal(svcId);
+
+        ModelObjectId sitesId = getModIdForSites();
+        sites = getResourceVal(sitesId);
+    }
+
+    /**
+     * Returns resource id from model converter.
+     *
+     * @param modelId model object id
+     * @return resource id
+     */
+    private ResourceId getResourceVal(ModelObjectId modelId) {
+        DefaultModelObjectData.Builder data = DefaultModelObjectData.builder()
+                .identifer(modelId);
+        ResourceData resData = modelConverter.createDataNode(data.build());
+        return resData.resourceId();
+    }
+
+    /**
+     * Processes create request from the store, by taking the root object.
+     * The root object is then used for l3VPN processing.
+     *
+     * @param storeId store resource id
+     */
+    private void processCreateFromStore(ResourceId storeId) {
+        List<ModelObject> objects = getModelObjects(storeId, module);
+        for (ModelObject obj : objects) {
+            if (obj instanceof DefaultL3VpnSvc) {
+                DefaultL3VpnSvc l3VpnSvc = (DefaultL3VpnSvc) obj;
+                createGlobalConfig(l3VpnSvc);
+            }
+        }
+    }
+
+    /**
+     * Returns model objects of the store. The data node is read from the
+     * config store. This returns the resource id's node. So the node's
+     * parent resource id is taken and the data node is given to model
+     * converter.
+     *
+     * @param storeId store resource id
+     * @param appId   parent resource id
+     * @return model objects
+     */
+    public List<ModelObject> getModelObjects(ResourceId storeId,
+                                             ResourceId appId) {
+        DataNode dataNode = configService.readNode(storeId, null);
+        ResourceData data = getResourceData(dataNode, appId);
+        ModelObjectData modelData = modelConverter.createModel(data);
+        return modelData.modelObjects();
+    }
+
+    /**
+     * Returns true if the event resource id points to the root level node
+     * only and event is for addition and deletion; false otherwise.
+     *
+     * @param event config event
+     * @return true if event is supported; false otherwise
+     */
+    public boolean isSupported(DynamicConfigEvent event) {
+        ResourceId rsId = event.subject();
+        List<NodeKey> storeKeys = rsId.nodeKeys();
+        List<NodeKey> regKeys = id.nodeKeys();
+        if (storeKeys != null) {
+            if (storeKeys.size() == 1) {
+                return storeKeys.get(0).equals(regKeys.get(1)) &&
+                        (event.type() == NODE_ADDED ||
+                                event.type() == NODE_DELETED);
+            }
+        }
+        return false;
+    }
+
+    /***
+     * Creation of all configuration in standard device model.
+     *
+     * @param l3VpnSvc l3VPN service object
+     */
+    void createGlobalConfig(L3VpnSvc l3VpnSvc) {
+        if (l3VpnSvc.vpnServices() != null) {
+            createVpnServices(l3VpnSvc.vpnServices());
+        }
+        if (l3VpnSvc.sites() != null) {
+            createInterfaceConfig(l3VpnSvc.sites());
+        }
+    }
+
+    /**
+     * Creates the VPN instances from the VPN services object, if only that
+     * VPN instance is not already created.
+     *
+     * @param vpnSvcs VPN services object
+     */
+    private void createVpnServices(VpnServices vpnSvcs) {
+        if (vpnSvcs != null && vpnSvcs.vpnSvc() != null) {
+            List<VpnSvc> svcList = vpnSvcs.vpnSvc();
+            for (VpnSvc svc : svcList) {
+                String vpnName = svc.vpnId().string();
+                l3VpnStore.addVpnInsIfAbsent(vpnName, new VpnInstance(vpnName));
+            }
+        }
+    }
+
+    /**
+     * Creates interface configuration from the site network access if
+     * available.
+     *
+     * @param sites sites object
+     */
+    private void createInterfaceConfig(Sites sites) {
+        if (sites.site() != null) {
+            List<Site> sitesList = sites.site();
+            for (Site site : sitesList) {
+                if (site.siteNetworkAccesses() != null) {
+                    SiteNetworkAccesses accesses = site.siteNetworkAccesses();
+                    List<SiteNetworkAccess> accessList =
+                            accesses.siteNetworkAccess();
+                    for (SiteNetworkAccess access : accessList) {
+                        createFromAccess(access, site.siteId().string());
+                    }
+                }
+            }
+        }
+    }
+
+    /**
+     * Creates the interface and VPN related configurations from the access
+     * and site id value.
+     *
+     * @param access site network access
+     * @param siteId site id
+     */
+    private void createFromAccess(SiteNetworkAccess access, String siteId) {
+        Map<AccessInfo, InterfaceInfo> intMap = l3VpnStore.getInterfaceInfo();
+        Map<String, VpnInstance> insMap = l3VpnStore.getVpnInstances();
+        String accessId = access.siteNetworkAccessId().string();
+        AccessInfo info = new AccessInfo(siteId, accessId);
+
+        if (intMap.get(info) == null) {
+            VpnSiteRole siteRole = getSiteRole(access.vpnAttachment());
+            VpnInstance instance = insMap.get(siteRole.name());
+            if (instance == null) {
+                throw new NetL3VpnException(SITE_VPN_MISMATCH);
+            }
+            buildFromAccess(instance, info, access, siteRole);
+        }
+    }
+
+    /**
+     * Returns the VPN site role from the VPN attachment.
+     *
+     * @param attach VPN attachment
+     * @return VPN site role
+     */
+    private VpnSiteRole getSiteRole(VpnAttachment attach) {
+        if (attach == null || attach.attachmentFlavor() == null) {
+            throw new NetL3VpnException(VPN_ATTACHMENT_NULL);
+        }
+        AttachmentFlavor flavor = attach.attachmentFlavor();
+        if (!(flavor instanceof DefaultVpnId)) {
+            throw new NetL3VpnException(VPN_POLICY_NOT_SUPPORTED);
+        }
+        DefaultVpnId vpnId = (DefaultVpnId) flavor;
+        if (vpnId.siteRole() == null) {
+            throw new NetL3VpnException(SITE_ROLE_NULL);
+        }
+        VpnType role = getRole(vpnId.siteRole());
+        VpnSiteRole vpnRole = new VpnSiteRole(
+                String.valueOf(vpnId.vpnId()), role);
+        return vpnRole;
+    }
+
+    /**
+     * Builds the required details for device standard model from the site
+     * network access info available.
+     *
+     * @param instance VPN instance
+     * @param info     access info
+     * @param access   network access
+     * @param role     VPN site role
+     */
+    private void buildFromAccess(VpnInstance instance, AccessInfo info,
+                                 SiteNetworkAccess access, VpnSiteRole role) {
+        Bearer bearer = access.bearer();
+        if (bearer == null) {
+            throw new NetL3VpnException(BEARER_NULL);
+        }
+
+        RequestedType reqType = bearer.requestedType();
+        IpConnection connect = access.ipConnection();
+        RoutingProtocols pro = access.routingProtocols();
+
+        if (reqType == null || connect == null) {
+            throw new NetL3VpnException(IP_INT_INFO_NULL);
+        }
+        buildDeviceDetails(instance, info, role, bearer, connect,
+                           reqType, pro);
+    }
+
+    /**
+     * Builds the device details such as, VPN instance value if it is for
+     * the first time, interface values and BGP info if available in service.
+     *
+     * @param instance VPN instance
+     * @param accInfo  access info
+     * @param role     VPN site role
+     * @param bearer   bearer object
+     * @param connect  ip connect object
+     * @param reqType  requested type
+     * @param pro      routing protocol
+     */
+    private void buildDeviceDetails(VpnInstance instance, AccessInfo accInfo,
+                                    VpnSiteRole role, Bearer bearer,
+                                    IpConnection connect, RequestedType reqType,
+                                    RoutingProtocols pro) {
+        Map<AccessInfo, InterfaceInfo> interMap = l3VpnStore.getInterfaceInfo();
+        InterfaceInfo intInfo = interMap.get(accInfo);
+        if (intInfo != null) {
+            return;
+        }
+
+        DeviceInfo info = buildDevVpnIns(bearer, instance, role, connect);
+        String portName = getInterfaceName(info, reqType);
+        buildDevVpnInt(info, instance, connect, portName, accInfo);
+
+        if (pro != null && pro.routingProtocol() != null) {
+            buildBgpInfo(pro.routingProtocol(), info,
+                         role.name(), connect, accInfo);
+        }
+        InterfaceInfo interInfo = new InterfaceInfo(info, portName,
+                                                    instance.vpnName());
+        l3VpnStore.addInterfaceInfo(accInfo, interInfo);
+    }
+
+    /**
+     * Builds device VPN instance with the service objects. It returns
+     *
+     * @param bearer  bearer object
+     * @param ins     VPN instance
+     * @param role    VPN site role
+     * @param connect ip connection
+     * @return return
+     */
+    private DeviceInfo buildDevVpnIns(Bearer bearer, VpnInstance ins,
+                                      VpnSiteRole role, IpConnection connect) {
+        DefaultAugmentedL3VpnBearer augBearer = ((DefaultBearer) bearer)
+                .augmentation(DefaultAugmentedL3VpnBearer.class);
+        DeviceId id = getDeviceId(augBearer);
+        Map<DeviceId, DeviceInfo> devices = ins.devInfo();
+        DeviceInfo info = null;
+        if (devices != null) {
+            info = devices.get(id);
+        }
+        if (info == null) {
+            info = createVpnInstance(id, role, ins, connect);
+        }
+        return info;
+    }
+
+    /**
+     * Returns the device id from the bearer augment attachment of service.
+     * If the attachment in augment is not available it throws error.
+     *
+     * @param attach augmented bearer
+     * @return device id
+     */
+    private DeviceId getDeviceId(DefaultAugmentedL3VpnBearer attach) {
+        if (attach == null || attach.bearerAttachment() == null ||
+                attach.bearerAttachment().peMgmtIp() == null ||
+                attach.bearerAttachment().peMgmtIp().string() == null) {
+            throw new NetL3VpnException(DEVICE_INFO_NULL);
+        }
+        String ip = attach.bearerAttachment().peMgmtIp().string();
+        return getId(ip);
+    }
+
+    /**
+     * Returns the device id whose management ip address matches with the ip
+     * received.
+     *
+     * @param ip ip address
+     * @return device id
+     */
+    public DeviceId getId(String ip) {
+        for (Device device : deviceService.getAvailableDevices()) {
+            String val = device.annotations().value(MG_MT_ADD);
+            if (ip.equals(val)) {
+                return device.id();
+            }
+        }
+        throw new NetL3VpnException(getMgmtIpUnAvailErr(ip));
+    }
+
+    /**
+     * Creates the VPN instance by constructing standard device model of
+     * instances. It adds the RD and RT values to the VPN instance.
+     *
+     * @param id   device id
+     * @param role VPN site role
+     * @param inst VPN instance
+     * @param ip   ip connection
+     * @return device info
+     */
+    private DeviceInfo createVpnInstance(DeviceId id, VpnSiteRole role,
+                                         VpnInstance inst, IpConnection ip) {
+        Map<AccessInfo, InterfaceInfo> intMap = l3VpnStore.getInterfaceInfo();
+        generateRdRt(inst, role);
+        DeviceInfo info = new DeviceInfo(id);
+        inst.addDevInfo(id, info);
+
+        NetworkInstances instances = createInstance(inst, role, ip);
+        ModelObjectData devMod = getVpnCreateModObj(intMap, instances,
+                                                    id.toString());
+        ModelObjectData driMod = info.processCreateInstance(driverService,
+                                                            devMod);
+        ResourceData resData = modelConverter.createDataNode(driMod);
+        addToStore(resData);
+        return info;
+    }
+
+    /**
+     * Adds the resource data that is received from the driver, after
+     * converting from the model object data.
+     *
+     * @param resData resource data
+     */
+    private void addToStore(ResourceData resData) {
+        if (resData != null && resData.dataNodes() != null) {
+            List<DataNode> dataNodes = resData.dataNodes();
+            for (DataNode node : dataNodes) {
+                configService.createNodeRecursive(resData.resourceId(), node);
+            }
+        }
+    }
+
+    /**
+     * Generates RD and RT value for the VPN instance for the first time VPN
+     * instance creation.
+     *
+     * @param ins  VPN instance
+     * @param role VPN site role
+     */
+    private void generateRdRt(VpnInstance ins, VpnSiteRole role) {
+        ins.type(role.role());
+        VpnConfig config = ins.vpnConfig();
+        String rd = null;
+        if (config == null) {
+            rd = getIdFromGen();
+        }
+        switch (ins.type()) {
+            case ANY_TO_ANY:
+                if (config == null) {
+                    config = new FullMeshVpnConfig(rd);
+                    config.rd(rd);
+                }
+                break;
+
+            case HUB:
+            case SPOKE:
+                if (config == null) {
+                    config = new HubSpokeVpnConfig();
+                    config.rd(rd);
+                }
+                createImpRtVal((HubSpokeVpnConfig) config, ins.type());
+                createExpRtVal((HubSpokeVpnConfig) config, ins.type());
+                break;
+
+            default:
+                throw new NetL3VpnException(VPN_TYPE_UNSUPPORTED);
+        }
+        ins.vpnConfig(config);
+    }
+
+    /**
+     * Creates import RT value for HUB and SPOKE, according to the type, if
+     * the values are not present.
+     *
+     * @param config VPN config
+     * @param type   VPN type
+     */
+    private void createImpRtVal(HubSpokeVpnConfig config, VpnType type) {
+        if (type == HUB) {
+            if (config.hubImpRt() != null) {
+                return;
+            }
+            setHubImpRt(config);
+        } else {
+            if (config.spokeImpRt() != null) {
+                return;
+            }
+            config.spokeImpRt(config.rd());
+        }
+    }
+
+    /**
+     * Sets the HUB import RT, from the spoke export RT. If it is not
+     * available a new ID is generated.
+     *
+     * @param config VPN config
+     */
+    public void setHubImpRt(HubSpokeVpnConfig config) {
+        String hubImp;
+        if (config.spokeExpRt() != null) {
+            hubImp = config.spokeExpRt();
+        } else {
+            hubImp = getIdFromGen();
+        }
+        config.hubImpRt(hubImp);
+    }
+
+    /**
+     * Creates export RT value for HUB and SPOKE, according to the type, if
+     * the values are not present.
+     *
+     * @param config VPN config
+     * @param type   VPN type
+     */
+    private void createExpRtVal(HubSpokeVpnConfig config, VpnType type) {
+        if (type == HUB) {
+            if (config.hubExpRt() != null) {
+                return;
+            }
+            config.hubExpRt(config.rd());
+        } else {
+            if (config.spokeExpRt() != null) {
+                return;
+            }
+            setSpokeExpRt(config);
+        }
+    }
+
+    /**
+     * Sets the SPOKE export RT, from the hub import RT. If it is not
+     * available a new ID is generated.
+     *
+     * @param config VPN config
+     */
+    public void setSpokeExpRt(HubSpokeVpnConfig config) {
+        String spokeExp;
+        if (config.hubImpRt() != null) {
+            spokeExp = config.hubImpRt();
+        } else {
+            spokeExp = getIdFromGen();
+        }
+        config.spokeExpRt(spokeExp);
+    }
+
+    /**
+     * Returns the interface name from the requested type service object.
+     *
+     * @param info    device info
+     * @param reqType requested type
+     * @return interface name
+     */
+    private String getInterfaceName(DeviceInfo info, RequestedType reqType) {
+        DefaultAugmentedL3VpnRequestedType req =
+                ((DefaultRequestedType) reqType).augmentation(
+                        DefaultAugmentedL3VpnRequestedType.class);
+        if (req == null || req.requestedTypeProfile() == null ||
+                req.requestedTypeProfile().requestedTypeChoice() == null) {
+            throw new NetL3VpnException(INT_INFO_NULL);
+        }
+        RequestedTypeChoice reqChoice = req.requestedTypeProfile()
+                .requestedTypeChoice();
+        return getNameFromChoice(reqChoice, info.deviceId());
+    }
+
+    /**
+     * Returns the interface name from the type choice provided.
+     *
+     * @param choice service choice
+     * @param id     device id
+     * @return interface name
+     */
+    private String getNameFromChoice(RequestedTypeChoice choice, DeviceId id) {
+        if (choice == null) {
+            throw new NetL3VpnException(INT_INFO_NULL);
+        }
+        String intName;
+        if (choice instanceof DefaultDot1Qcase) {
+            if (((DefaultDot1Qcase) choice).dot1q() == null ||
+                    ((DefaultDot1Qcase) choice).dot1q()
+                            .physicalIf() == null) {
+                throw new NetL3VpnException(INT_INFO_NULL);
+            }
+            intName = ((DefaultDot1Qcase) choice).dot1q().physicalIf();
+        } else {
+            if (((DefaultPhysicalCase) choice).physical() == null ||
+                    ((DefaultPhysicalCase) choice).physical()
+                            .physicalIf() == null) {
+                throw new NetL3VpnException(INT_INFO_NULL);
+            }
+            intName = ((DefaultPhysicalCase) choice).physical().physicalIf();
+        }
+        return getPortName(intName, id);
+    }
+
+    /**
+     * Returns the port name when it the port is available in the device.
+     *
+     * @param intName interface name
+     * @param id      device id
+     * @return port name
+     */
+    private String getPortName(String intName, DeviceId id) {
+        List<Port> ports = deviceService.getPorts(id);
+        for (Port port : ports) {
+            String pName = port.annotations().value(PORT_NAME);
+            if (pName.equals(intName)) {
+                return intName;
+            }
+        }
+        throw new NetL3VpnException(getIntNotAvailable(intName));
+    }
+
+    /**
+     * Builds the interface for the device binding with the VPN instance.
+     *
+     * @param info    device info
+     * @param ins     VPN instance
+     * @param connect IP connection
+     * @param pName   port name
+     * @param access  access info
+     */
+    private void buildDevVpnInt(DeviceInfo info, VpnInstance ins,
+                                IpConnection connect, String pName,
+                                AccessInfo access) {
+        Map<AccessInfo, InterfaceInfo> intMap = l3VpnStore.getInterfaceInfo();
+        info.addAccessInfo(access);
+        info.addIfName(pName);
+        Interfaces interfaces = createInterface(pName, ins.vpnName(),
+                                                connect);
+        ModelObjectData devMod = getIntCreateModObj(
+                intMap, interfaces, info.deviceId().toString());
+        ModelObjectData driMod = info.processCreateInterface(driverService,
+                                                             devMod);
+        ResourceData resData = modelConverter.createDataNode(driMod);
+        addToStore(resData);
+    }
+
+    /**
+     * Builds the BGP information from the routes that are given from the
+     * service.
+     *
+     * @param routes  routing protocol
+     * @param info    device info
+     * @param name    VPN name
+     * @param connect IP connection
+     * @param access  access info
+     */
+    private void buildBgpInfo(List<RoutingProtocol> routes, DeviceInfo info,
+                              String name, IpConnection connect,
+                              AccessInfo access) {
+        Map<BgpInfo, DeviceId> bgpMap = l3VpnStore.getBgpInfo();
+        BgpInfo intBgp = createBgpInfo(routes, info, name, connect, access);
+        if (intBgp != null) {
+            intBgp.vpnName(name);
+            BgpDriverInfo config = getBgpCreateConfigObj(
+                    bgpMap, info.deviceId().toString());
+            ModelObjectData driData = info.processCreateBgpInfo(
+                    driverService, intBgp, config);
+            l3VpnStore.addBgpInfo(info.bgpInfo(), info.deviceId());
+            ResourceData resData = modelConverter.createDataNode(driData);
+            addToStore(resData);
+        }
+    }
+
+    /**
+     * Representation of internal listener, listening for dynamic config event.
+     */
+    private class InternalConfigListener implements DynamicConfigListener {
+
+        @Override
+        public boolean isRelevant(DynamicConfigEvent event) {
+            return isSupported(event);
+        }
+
+        @Override
+        public void event(DynamicConfigEvent event) {
+            executor.execute(() -> {
+                try {
+                    ResourceId rsId = event.subject();
+                    switch (event.type()) {
+                        case NODE_ADDED:
+                            processCreateFromStore(rsId);
+                            break;
+
+                        case NODE_DELETED:
+                            //TODO: To be committed.
+                            break;
+
+                        default:
+                            throw new NetL3VpnException(EVENT_NOT_SUPPORTED);
+                    }
+                } catch (Exception e) {
+                    log.warn("Failed to process {}", event, e);
+                }
+            });
+        }
+    }
 }