diff --git a/apps/tenbi/utils/src/main/java/org/onosproject/teyang/utils/topology/LinkConverter.java b/apps/tenbi/utils/src/main/java/org/onosproject/teyang/utils/topology/LinkConverter.java
new file mode 100644
index 0000000..24518d8
--- /dev/null
+++ b/apps/tenbi/utils/src/main/java/org/onosproject/teyang/utils/topology/LinkConverter.java
@@ -0,0 +1,980 @@
+/*
+ * Copyright 2016 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.teyang.utils.topology;
+
+import static com.google.common.base.Preconditions.checkNotNull;
+
+import java.util.List;
+
+import org.onosproject.tetopology.management.api.KeyId;
+import org.onosproject.tetopology.management.api.link.ExternalDomain;
+import org.onosproject.tetopology.management.api.link.LinkProtectionType;
+import org.onosproject.tetopology.management.api.link.NetworkLinkKey;
+import org.onosproject.tetopology.management.api.link.PathElement;
+import org.onosproject.tetopology.management.api.link.TeLink;
+import org.onosproject.tetopology.management.api.link.UnderlayBackupPath;
+import org.onosproject.tetopology.management.api.link.UnderlayPath;
+import org.onosproject.tetopology.management.api.node.TeNetworkTopologyId;
+import org.onosproject.tetopology.management.api.node.TerminationPointKey;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.rev20151208.ietfnetwork.NetworkId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.rev20151208.ietfnetwork.NodeId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.LinkId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.TpId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.DefaultLink;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.DefaultLink.LinkBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.Link;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.link.DefaultDestination;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.link.DefaultSource;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.link.DefaultSupportingLink;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+                .ietfnetworktopology.networks.network.augmentedndnetwork.link.Destination
+                .DestinationBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.link.Source.SourceBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.link.SupportingLink;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.network.topology.rev20151208
+               .ietfnetworktopology.networks.network.augmentedndnetwork.link.SupportingLink
+               .SupportingLinkBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.augmentednwnetworks.te.templates.linktemplate
+               .telinkattributes.LinkProtectionTypeEnum;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.AugmentedNtLink;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.DefaultAugmentedNtLink;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.DefaultAugmentedNtLink.AugmentedNtLinkBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.DefaultTe;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.DefaultTe.TeBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.Config;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+.ietftetopology.networks.network.link.augmentedntlink.te.Config.ConfigBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.DefaultConfig;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.DefaultState;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.State;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+.ietftetopology.networks.network.link.augmentedntlink.te.State.StateBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.DefaultTeLinkAttributes;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.TeLinkAttributes;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.TeLinkAttributes
+               .TeLinkAttributesBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .DefaultExternalDomain;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .DefaultExternalDomain.ExternalDomainBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes.DefaultTeSrlgs;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes.DefaultUnderlay;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .DefaultUnreservedBandwidth;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes.TeSrlgs
+               .TeSrlgsBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes.Underlay;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes.Underlay
+               .UnderlayBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .UnreservedBandwidth;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .UnreservedBandwidth.UnreservedBandwidthBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.DefaultUnderlayBackupPath;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708.ietftetopology
+               .networks.network.link.augmentedntlink.te.config.telinkattributes.underlay
+               .DefaultUnderlayBackupPath.UnderlayBackupPathBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.DefaultUnderlayPrimaryPath;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.DefaultUnderlayTrailDes.UnderlayTrailDesBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.DefaultUnderlayTrailSrc.UnderlayTrailSrcBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.UnderlayPrimaryPath;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.UnderlayPrimaryPath.UnderlayPrimaryPathBuilder;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+               .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+               .underlay.underlayprimarypath.DefaultPathElement;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.types.rev20160705.ietftetypes.Srlg;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.types.rev20160705.ietftetypes.TeLinkAccessType;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.types.rev20160705.ietftetypes.TeNodeId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.types.rev20160705.ietftetypes.TeTopologyId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.types.rev20160705.ietftetypes.TeTpId;
+import org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.types.rev20160705
+               .ietftetypes.telinkaccesstype.TeLinkAccessTypeEnum;
+
+import com.google.common.collect.Lists;
+
+/**
+ * The conversion functions.
+ */
+public final class LinkConverter {
+    private static final String
+        E_NULL_TELINK_UNDERLAY_PATH = "TeSubsystem link underlayPath object cannot be null";
+    private static final String
+        E_NULL_TELINK_DATA = "TeSubsystem teLink data cannot be null";
+    private static final String
+        E_NULL_TELINK = "TeSubsystem teLink object cannot be null";
+    private static final String
+        E_NULL_YANG_TELINK_CONFIG = "YANG telink config object cannot be null";
+    private static final String
+        E_NULL_YANG_TELINK = "YANG Link object cannot be null";
+
+    // no instantiation
+    private LinkConverter() {
+    }
+
+    private static UnderlayBuilder te2YangConfigUnderlayPrimaryPath(
+            UnderlayBuilder yangBuilder,
+            org.onosproject.tetopology.management.api.link.UnderlayPrimaryPath tePath) {
+        UnderlayPrimaryPathBuilder pathBuilder =
+                                       DefaultUnderlayPrimaryPath.builder();
+        if (tePath.pathElements() != null) {
+            for (PathElement pathElementTe : tePath.pathElements()) {
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .config.telinkattributes.underlay.underlayprimarypath.PathElement
+                   .PathElementBuilder pathElementYangBuilder = DefaultPathElement.builder();
+                // FIXME: pathElementTe does not have any getter or
+                // setter at the moment --> pathElementYangBuilder =
+                // pathElementYangBuilder.pathElementId(pathElementTe.getPathElementId());
+                pathBuilder = pathBuilder.addToPathElement(pathElementYangBuilder.build());
+            }
+        }
+        pathBuilder = pathBuilder.networkIdRef(NetworkId.fromString(
+                                               tePath.ref().getNetworkId().toString()))
+                                 .teTopologyIdRef(TeTopologyId.fromString(
+                                               tePath.ref().getTopologyId().topologyId()));
+        return yangBuilder.underlayPrimaryPath(pathBuilder.build());
+    }
+
+    private static UnderlayBuilder te2YangConfigUnderlayBackupPaths(
+            UnderlayBuilder yangBuilder,
+            List<org.onosproject.tetopology.management.api.link.UnderlayBackupPath> tePaths) {
+
+        for (UnderlayBackupPath tePath : tePaths) {
+            UnderlayBackupPathBuilder pathBuilder = DefaultUnderlayBackupPath.builder();
+            pathBuilder = pathBuilder.index(tePath.index());
+            pathBuilder = pathBuilder.networkIdRef(NetworkId.fromString(
+                                                        tePath.ref().getNetworkId().toString()))
+                                     .teTopologyIdRef(TeTopologyId.fromString(
+                                                        tePath.ref().getTopologyId().topologyId()));
+            for (PathElement backupPathElementTe : tePath.pathElements()) {
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .config.telinkattributes.underlay.underlaybackuppath.PathElement
+                   .PathElementBuilder elementBuilder =
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .config.telinkattributes.underlay.underlaybackuppath.DefaultPathElement.builder();
+                // FIXME: backupPathElementTe does not have any
+                // getter or setter at the moment -->
+                // elementBuilder =
+                // elementBuilder.pathElementId(backupPathElementTe.getPathElementId());
+                pathBuilder = pathBuilder.addToPathElement(elementBuilder.build());
+            }
+            yangBuilder = yangBuilder.addToUnderlayBackupPath(pathBuilder.build());
+        }
+
+        return yangBuilder;
+    }
+
+    /**
+     * TE Link underlay path Config object conversion from TE Topology subsystem to YANG.
+     *
+     * @param  tePath TE underlay path object
+     * @return Link underlay path Config YANG object
+     */
+    private static Underlay teSubsystem2YangConfigUnderlayPath(UnderlayPath tePath) {
+        checkNotNull(tePath, E_NULL_TELINK_UNDERLAY_PATH);
+        UnderlayBuilder builder =
+                DefaultUnderlay.builder().underlayProtectionType(tePath.protectionType());
+
+        if (tePath.primaryPath() != null) {
+            builder = te2YangConfigUnderlayPrimaryPath(builder, tePath.primaryPath());
+        }
+        if (tePath.trailSrc() != null) {
+            builder = builder.underlayTrailSrc(
+                                  new UnderlayTrailSrcBuilder()
+                                          .networkRef(NetworkId.fromString(
+                                                  tePath.trailSrc().networkId().toString()))
+                                          .nodeRef(NodeId.fromString(
+                                                  tePath.trailSrc().nodeId().toString()))
+                                          .tpRef(TpId.fromString(
+                                                  tePath.trailSrc().tpId().toString()))
+                                          .build());
+        }
+        if (tePath.trailDes() != null) {
+            builder = builder.underlayTrailDes(
+                                  new UnderlayTrailDesBuilder()
+                                          .networkRef(NetworkId.fromString(
+                                                  tePath.trailDes().networkId().toString()))
+                                          .nodeRef(NodeId.fromString(
+                                                  tePath.trailDes().nodeId().toString()))
+                                          .tpRef(TpId.fromString(
+                                                  tePath.trailDes().tpId().toString()))
+                                          .build());
+        }
+        if (tePath.backupPaths() != null) {
+            builder = te2YangConfigUnderlayBackupPaths(builder, tePath.backupPaths());
+        }
+
+        return builder.build();
+    }
+
+    private static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                      .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                      .state.telinkattributes.Underlay.UnderlayBuilder
+            te2YangStateUnderlayPrimaryPath(
+                   org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                      .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                      .state.telinkattributes.Underlay.UnderlayBuilder yangBuilder,
+                   org.onosproject.tetopology.management.api.link.UnderlayPrimaryPath tePath) {
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+            .underlay.UnderlayPrimaryPath.UnderlayPrimaryPathBuilder pathBuilder =
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+            .underlay.DefaultUnderlayPrimaryPath.builder();
+        if (tePath.pathElements() != null) {
+            for (PathElement pathElementTe : tePath.pathElements()) {
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .state.telinkattributes.underlay.underlayprimarypath.PathElement
+                   .PathElementBuilder pathElementYangBuilder =
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .state.telinkattributes.underlay.underlayprimarypath.DefaultPathElement
+                   .builder();
+                // FIXME: pathElementTe does not have any getter or
+                // setter at the moment --> pathElementYangBuilder =
+                // pathElementYangBuilder.pathElementId(pathElementTe.getPathElementId());
+                pathBuilder = pathBuilder.addToPathElement(pathElementYangBuilder.build());
+            }
+        }
+        pathBuilder = pathBuilder.networkIdRef(NetworkId.fromString(
+                                               tePath.ref().getNetworkId().toString()))
+                                 .teTopologyIdRef(TeTopologyId.fromString(
+                                               tePath.ref().getTopologyId().topologyId()));
+        return yangBuilder.underlayPrimaryPath(pathBuilder.build());
+    }
+
+    private static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                      .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                      .state.telinkattributes.Underlay.UnderlayBuilder
+           te2YangStateUnderlayBackupPaths(
+                   org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .state.telinkattributes.Underlay.UnderlayBuilder yangBuilder,
+            List<org.onosproject.tetopology.management.api.link.UnderlayBackupPath> tePaths) {
+
+        for (UnderlayBackupPath tePath : tePaths) {
+            org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+            .underlay.UnderlayBackupPath.UnderlayBackupPathBuilder
+            pathBuilder = org.onosproject.yang.gen.v1.urn.ietf.params.xml
+            .ns.yang.ietf.te.topology.rev20160708.ietftetopology.networks.network.link.augmentedntlink
+            .te.state.telinkattributes.underlay.DefaultUnderlayBackupPath
+                    .builder();
+
+            pathBuilder = pathBuilder.index(tePath.index());
+            pathBuilder = pathBuilder.networkIdRef(NetworkId.fromString(
+                                                        tePath.ref().getNetworkId().toString()))
+                                     .teTopologyIdRef(TeTopologyId.fromString(
+                                                        tePath.ref().getTopologyId().topologyId()));
+            for (PathElement backupPathElementTe : tePath.pathElements()) {
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .state.telinkattributes.underlay.underlaybackuppath.PathElement
+                   .PathElementBuilder elementBuilder =
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                   .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                   .state.telinkattributes.underlay.underlaybackuppath.DefaultPathElement.builder();
+                // FIXME: backupPathElementTe does not have any
+                // getter or setter at the moment -->
+                // elementBuilder =
+                // elementBuilder.pathElementId(backupPathElementTe.getPathElementId());
+                pathBuilder = pathBuilder.addToPathElement(elementBuilder.build());
+            }
+            yangBuilder = yangBuilder.addToUnderlayBackupPath(pathBuilder.build());
+        }
+
+        return yangBuilder;
+    }
+
+    /**
+     * TE Link underlay path State object conversion from TE Topology subsystem to YANG.
+     *
+     * @param tePath TE underlay object
+     * @return Link underlay path State YANG object
+     */
+    private static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                       .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te
+                       .state.telinkattributes.Underlay
+                   teSubsystem2YangStateUnderlayPath(UnderlayPath tePath) {
+        checkNotNull(tePath, E_NULL_TELINK_UNDERLAY_PATH);
+
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+            .Underlay.UnderlayBuilder builder =
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+            .DefaultUnderlay.builder().underlayProtectionType(tePath.protectionType());
+
+        if (tePath.primaryPath() != null) {
+            builder = te2YangStateUnderlayPrimaryPath(builder, tePath.primaryPath());
+
+        }
+        if (tePath.trailSrc() != null) {
+            builder = builder.underlayTrailSrc(
+                          new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te
+                                  .topology.rev20160708.ietftetopology.networks.network.link
+                                  .augmentedntlink.te.state.telinkattributes.underlay
+                                  .DefaultUnderlayTrailSrc.UnderlayTrailSrcBuilder()
+                              .networkRef(NetworkId.fromString(
+                                              tePath.trailSrc().networkId().toString()))
+                              .nodeRef(NodeId.fromString(
+                                              tePath.trailSrc().nodeId().toString()))
+                              .tpRef(TpId.fromString(
+                                              tePath.trailSrc().tpId().toString()))
+                              .build());
+        }
+        if (tePath.trailDes() != null) {
+            builder = builder.underlayTrailDes(
+                          new org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te
+                                   .topology.rev20160708.ietftetopology.networks.network.link
+                                   .augmentedntlink.te.state.telinkattributes.underlay
+                                   .DefaultUnderlayTrailDes.UnderlayTrailDesBuilder()
+                              .networkRef(NetworkId.fromString(
+                                              tePath.trailDes().networkId().toString()))
+                              .nodeRef(NodeId.fromString(
+                                              tePath.trailDes().nodeId().toString()))
+                              .tpRef(TpId.fromString(
+                                              tePath.trailDes().tpId().toString()))
+                              .build());
+        }
+        if (tePath.backupPaths() != null) {
+            builder = te2YangStateUnderlayBackupPaths(builder, tePath.backupPaths());
+        }
+
+        return builder.build();
+    }
+
+    /**
+     * TE Link Config object conversion from TE Topology subsystem to YANG.
+     *
+     * @param teLink TE link object
+     * @return TE Link Config YANG object
+     */
+    private static Config teLink2YangConfig(TeLink teLink) {
+        checkNotNull(teLink, E_NULL_TELINK_DATA);
+
+        TeLinkAttributesBuilder attrBuilder = DefaultTeLinkAttributes.builder();
+        if (teLink.linkIndex() != null) {
+            attrBuilder = attrBuilder.linkIndex(teLink.linkIndex());
+        }
+        if (teLink.name() != null) {
+            attrBuilder = attrBuilder.name(teLink.name());
+        }
+        if (teLink.adminStatus() != null) {
+            attrBuilder = attrBuilder
+                    .adminStatus(EnumConverter
+                            .teSubsystem2YangAdminStatus(teLink
+                            .adminStatus()));
+        }
+        if (teLink.accessType() != null) {
+            attrBuilder = attrBuilder
+                    .accessType(teSubsystem2YangTeLinkAccess(teLink
+                            .accessType()));
+        }
+        if (teLink.linkProtectionType() != null) {
+            attrBuilder = attrBuilder
+                    .linkProtectionType(teSubsystem2YangLinkProtectionType(teLink
+                            .linkProtectionType()));
+        }
+        if (teLink.maxLinkBandwidth() != null) {
+            attrBuilder = attrBuilder.maxLinkBandwidth(teLink.maxLinkBandwidth());
+        }
+        if (teLink.maxResvLinkBandwidth() != null) {
+            attrBuilder = attrBuilder.maxResvLinkBandwidth(teLink.maxResvLinkBandwidth());
+        }
+        attrBuilder = attrBuilder.teDefaultMetric(teLink.teDefaultMetric());
+        if (teLink.teSrlgs() != null) {
+            TeSrlgsBuilder teSrlgsBuilder = DefaultTeSrlgs.builder();
+            for (Long srlgLongVal : teLink.teSrlgs()) {
+                teSrlgsBuilder = teSrlgsBuilder.addToValue(new Srlg(srlgLongVal));
+            }
+            attrBuilder = attrBuilder.teSrlgs(teSrlgsBuilder.build());
+        }
+        attrBuilder = attrBuilder.isAbstract(teLink.isAbstract());
+        if (teLink.underlayPath() != null) {
+            attrBuilder = attrBuilder.underlay(
+                              teSubsystem2YangConfigUnderlayPath(teLink.underlayPath()));
+        }
+        if (teLink.externalDomain() != null) {
+            ExternalDomainBuilder edBuilder =
+                    DefaultExternalDomain.builder()
+                                         .plugId(teLink.externalDomain().plugId())
+                                         .remoteTeLinkTpId(TeTpId.fromString(
+                                                  teLink.externalDomain().remoteTeLinkTpId().toString()))
+                                         .remoteTeNodeId(TeNodeId.fromString(
+                                                  teLink.externalDomain().remoteTeNodeId().toString()));
+            attrBuilder = attrBuilder.externalDomain(edBuilder.build());
+        }
+
+        if (teLink.unreservedBandwidths() != null) {
+            for (org.onosproject.tetopology.management.api.link.UnreservedBandwidth unResBwTe :
+                        teLink.unreservedBandwidths()) {
+                UnreservedBandwidthBuilder urBuilder =
+                        DefaultUnreservedBandwidth.builder()
+                                                  .bandwidth(unResBwTe.bandwidth())
+                                                  .priority(unResBwTe.priority());
+                attrBuilder = attrBuilder.addToUnreservedBandwidth(urBuilder.build());
+            }
+        }
+
+        ConfigBuilder yangConfigBuilder = DefaultConfig.builder()
+                                                       .teLinkAttributes(attrBuilder.build());
+        return yangConfigBuilder.build();
+    }
+
+    private static LinkProtectionTypeEnum
+                        teSubsystem2YangLinkProtectionType(LinkProtectionType linkProtectionType) {
+        switch (linkProtectionType) {
+        case ENHANCED:
+            return LinkProtectionTypeEnum.ENHANCED;
+        case EXTRA_TRAFFIC:
+            return LinkProtectionTypeEnum.EXTRA_TRAFFIC;
+        case SHARED:
+            return LinkProtectionTypeEnum.SHARED;
+        case UNPROTECTED:
+            return LinkProtectionTypeEnum.UNPROTECTED;
+        case YANGAUTOPREFIX1_FOR_1:
+            return LinkProtectionTypeEnum.YANGAUTOPREFIX1_FOR_1;
+        case YANGAUTOPREFIX1_PLUS_1:
+            return LinkProtectionTypeEnum.YANGAUTOPREFIX1_PLUS_1;
+        default:
+            return null;
+        }
+    }
+
+    private static TeLinkAccessType teSubsystem2YangTeLinkAccess(
+                       org.onosproject.tetopology.management.api.link.TeLinkAccessType accessType) {
+        switch (accessType) {
+        case MULTI_ACCESS:
+            return TeLinkAccessType.of(TeLinkAccessTypeEnum.MULTI_ACCESS);
+        case POINT_TO_POINT:
+            return TeLinkAccessType.of(TeLinkAccessTypeEnum.POINT_TO_POINT);
+        default:
+            return null;
+        }
+    }
+
+    /**
+     * TE Link State object conversion from TE Topology subsystem to YANG.
+     *
+     * @param teLink TE link object
+     * @return TE Link State YANG object
+     */
+    private static State teLink2YangState(TeLink teLink) {
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.TeLinkAttributes
+            .TeLinkAttributesBuilder attrBuilder =
+        org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+            .ietftetopology.networks.network.link.augmentedntlink.te.state.DefaultTeLinkAttributes
+            .builder()
+            .teDefaultMetric(teLink.teDefaultMetric())
+            .isAbstract(teLink.isAbstract());
+        if (teLink.linkIndex() != null) {
+            attrBuilder = attrBuilder.linkIndex(teLink.linkIndex());
+        }
+        if (teLink.name() != null) {
+            attrBuilder = attrBuilder.name(teLink.name());
+        }
+        if (teLink.adminStatus() != null) {
+            attrBuilder = attrBuilder
+                    .adminStatus(EnumConverter
+                            .teSubsystem2YangAdminStatus(teLink
+                            .adminStatus()));
+        }
+        if (teLink.accessType() != null) {
+            attrBuilder = attrBuilder
+                    .accessType(teSubsystem2YangTeLinkAccess(teLink
+                            .accessType()));
+        }
+        if (teLink.linkProtectionType() != null) {
+            attrBuilder = attrBuilder
+                    .linkProtectionType(teSubsystem2YangStateLinkProtectionType(teLink
+                            .linkProtectionType()));
+        }
+        if (teLink.maxLinkBandwidth() != null) {
+            attrBuilder = attrBuilder.maxLinkBandwidth(teLink.maxLinkBandwidth());
+        }
+        if (teLink.maxResvLinkBandwidth() != null) {
+            attrBuilder = attrBuilder.maxResvLinkBandwidth(teLink.maxResvLinkBandwidth());
+        }
+        if (teLink.teSrlgs() != null) {
+            org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+                .TeSrlgs.TeSrlgsBuilder srlgsBuilder =
+            org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+                .DefaultTeSrlgs.builder();
+            for (Long srlgLongVal : teLink.teSrlgs()) {
+                srlgsBuilder = srlgsBuilder.addToValue(new Srlg(srlgLongVal));
+            }
+            attrBuilder = attrBuilder.teSrlgs(srlgsBuilder.build());
+        }
+        if (teLink.underlayPath() != null) {
+            attrBuilder = attrBuilder.underlay(teSubsystem2YangStateUnderlayPath(teLink.underlayPath()));
+        }
+        if (teLink.externalDomain() != null) {
+            org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                    .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+                    .ExternalDomain.ExternalDomainBuilder edBuilder =
+            org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                    .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+                    .DefaultExternalDomain.builder()
+                                          .plugId(teLink.externalDomain().plugId())
+                                          .remoteTeLinkTpId(TeTpId.fromString(
+                                                  teLink.externalDomain().remoteTeLinkTpId().toString()))
+                                          .remoteTeNodeId(TeNodeId.fromString(
+                                                  teLink.externalDomain().remoteTeNodeId().toString()));
+            attrBuilder = attrBuilder.externalDomain(edBuilder.build());
+        }
+        if (teLink.unreservedBandwidths() != null) {
+            for (org.onosproject.tetopology.management.api.link.UnreservedBandwidth unResBwTe :
+                    teLink.unreservedBandwidths()) {
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                    .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+                    .UnreservedBandwidth.UnreservedBandwidthBuilder urBuilder =
+                org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                    .ietftetopology.networks.network.link.augmentedntlink.te.state.telinkattributes
+                    .DefaultUnreservedBandwidth.builder()
+                                               .bandwidth(unResBwTe.bandwidth())
+                                               .priority(unResBwTe.priority());
+                attrBuilder = attrBuilder.addToUnreservedBandwidth(urBuilder.build());
+            }
+        }
+
+        StateBuilder yangStateBuilder = DefaultState.builder()
+                                                    .teLinkAttributes(attrBuilder.build());
+        if (teLink.opStatus() != null) {
+            yangStateBuilder = yangStateBuilder
+                    .operStatus(EnumConverter
+                            .teSubsystem2YangOperStatus(teLink
+                            .opStatus()));
+        }
+
+        return yangStateBuilder.build();
+    }
+
+    private static org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+        rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+        LinkProtectionTypeEnum teSubsystem2YangStateLinkProtectionType(LinkProtectionType linkProtectionType) {
+        switch (linkProtectionType) {
+        case ENHANCED:
+            return org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+                    rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+                    LinkProtectionTypeEnum.ENHANCED;
+        case EXTRA_TRAFFIC:
+            return org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+                    rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+                    LinkProtectionTypeEnum.EXTRA_TRAFFIC;
+        case SHARED:
+            return org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+                    rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+                    LinkProtectionTypeEnum.SHARED;
+        case UNPROTECTED:
+            return org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+                    rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+                    LinkProtectionTypeEnum.UNPROTECTED;
+        case YANGAUTOPREFIX1_FOR_1:
+            return org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+                    rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+                    LinkProtectionTypeEnum.YANGAUTOPREFIX1_FOR_1;
+        case YANGAUTOPREFIX1_PLUS_1:
+            return org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.
+                    rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.state.informationsourceentry.
+                    LinkProtectionTypeEnum.YANGAUTOPREFIX1_PLUS_1;
+        default:
+            return null;
+        }
+    }
+
+    /**
+     * Link object conversion from TE Topology subsystem to YANG.
+     *
+     * @param teLink TE subsystem link object
+     * @return YANG link object
+     */
+    public static Link teSubsystem2YangLink(
+            org.onosproject.tetopology.management.api.link.NetworkLink teLink) {
+        checkNotNull(teLink, E_NULL_TELINK);
+
+        LinkId linkId = LinkId.fromString(teLink.linkId().toString());
+        LinkBuilder builder = DefaultLink.builder().linkId(linkId);
+        if (teLink.getSupportingLinkIds() != null) {
+            List<SupportingLink> slinks = Lists.newArrayList();
+            SupportingLinkBuilder spLinkBuilder = DefaultSupportingLink.builder();
+            for (NetworkLinkKey linkKey : teLink.getSupportingLinkIds()) {
+                slinks.add(spLinkBuilder.networkRef(NetworkId.fromString(
+                                                    linkKey.networkId().toString()))
+                                        .linkRef(LinkId.fromString(
+                                                    linkKey.linkId().toString()))
+                                        .build());
+            }
+            builder = builder.supportingLink(slinks);
+        }
+        if (teLink.getSource() != null) {
+            SourceBuilder sourceBuilder = DefaultSource
+                                              .builder()
+                                              .sourceNode(NodeId.fromString(
+                                                   teLink.getSource().nodeId().toString()))
+                                              .sourceTp(TpId.fromString(
+                                                   teLink.getSource().tpId().toString()));
+            builder = builder.source(sourceBuilder.build());
+        }
+        if (teLink.getDestination() != null) {
+            DestinationBuilder destBuilder = DefaultDestination
+                                                 .builder()
+                                                 .destNode(NodeId.fromString(
+                                                      teLink.getDestination().nodeId().toString()))
+                                                 .destTp(TpId.fromString(
+                                                      teLink.getDestination().tpId().toString()));
+            builder = builder.destination(destBuilder.build());
+        }
+
+        if (teLink.getTe() != null) {
+            TeLink teData = teLink.getTe();
+            TeBuilder yangTeBuilder = DefaultTe.builder()
+                                               .config(teLink2YangConfig(teData))
+                                               .state(teLink2YangState(teData));
+            AugmentedNtLinkBuilder linkAugmentBuilder =
+                    DefaultAugmentedNtLink.builder()
+                                          .te(yangTeBuilder.build());
+            builder.addYangAugmentedInfo(linkAugmentBuilder.build(), AugmentedNtLink.class);
+        }
+
+        return builder.build();
+    }
+
+    private static org.onosproject.tetopology.management.api.link.UnderlayPath
+           yang2TeSubsystemUnderlayPrimaryPath(
+                            org.onosproject.tetopology.management.api.link.UnderlayPath teUnderlay,
+                            UnderlayPrimaryPath yangpath) {
+        org.onosproject.tetopology.management.api.link.UnderlayPrimaryPath teUnderlayPrimaryPath =
+                new org.onosproject.tetopology.management.api.link.UnderlayPrimaryPath();
+        teUnderlayPrimaryPath.setRef(new TeNetworkTopologyId(KeyId.keyId(
+                                             yangpath.networkIdRef().toString()),
+                                     new org.onosproject.tetopology.management.api.TeTopologyId(
+                                             yangpath.providerIdRef().uint32(),
+                                             yangpath.clientIdRef().uint32(),
+                                             yangpath.teTopologyIdRef().toString())));
+
+        List<PathElement> pathElementList = Lists.newArrayList();
+        for (org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+                .underlay.underlayprimarypath.PathElement pathElementConfigYang :
+                    yangpath.pathElement()) {
+            //PathElement tePathElement = new PathElement();
+            // FIXME: tePathElement does not have any getter
+            // or setter at the moment -->
+            // tePathElement.set...
+            // TODO: construct the tePathElement object
+            // properly using pathElementConfigYang
+            //pathElementList.add(tePathElement);
+        }
+        teUnderlayPrimaryPath.setPathElement(pathElementList);
+        teUnderlay.setPrimaryPath(teUnderlayPrimaryPath);
+
+        return teUnderlay;
+    }
+
+    private static org.onosproject.tetopology.management.api.link.UnderlayPath
+            yang2TeSubsystemUnderlayBackupPaths(
+                     org.onosproject.tetopology.management.api.link.UnderlayPath teUnderlay,
+                     List<org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te
+                             .topology.rev20160708.ietftetopology.networks.network.link
+                             .augmentedntlink.te.config.telinkattributes.underlay
+                             .UnderlayBackupPath> yangpaths) {
+        List<UnderlayBackupPath> underlayBackupPathsList = Lists.newArrayList();
+        for (org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology.rev20160708
+                .ietftetopology.networks.network.link.augmentedntlink.te.config.telinkattributes
+                    .underlay.UnderlayBackupPath yangConfig : yangpaths) {
+            UnderlayBackupPath ubp = new UnderlayBackupPath();
+            ubp.setIndex(yangConfig.index());
+            ubp.setRef(new TeNetworkTopologyId(KeyId.keyId(yangConfig.networkIdRef().toString()),
+                                               new org.onosproject.tetopology.management.api.TeTopologyId(
+                                                       yangConfig.providerIdRef().uint32(),
+                                                       yangConfig.clientIdRef().uint32(),
+                                                       yangConfig.teTopologyIdRef().toString()
+                                              )));
+            List<PathElement> backupPathElementList = Lists.newArrayList();
+            for (org.onosproject.yang.gen.v1.urn.ietf.params.xml.ns.yang.ietf.te.topology
+                    .rev20160708.ietftetopology.networks.network.link.augmentedntlink.te.config
+                    .telinkattributes.underlay.underlaybackuppath.PathElement
+                        pathElementBackupYang : yangConfig.pathElement()) {
+                //PathElement tePathElementBackup = new PathElement();
+                // FIXME: tePathElement does not have any
+                // getter or setter at the moment -->
+                // tePathElement.set...
+                // TODO: construct the tePathElement object
+                // properly using pathElementBackupYang
+                //backupPathElementList.add(tePathElementBackup);
+            }
+            ubp.setPathElement(backupPathElementList);
+        }
+        teUnderlay.setBackupPath(underlayBackupPathsList);
+
+        return teUnderlay;
+    }
+
+    /**
+     * TE Link underlay path Config object conversion from YANG to TE Topology subsystem.
+     *
+     * @param yangLinkAtrr YANG link Config YANG object
+     * @return teSubsystem TE underlay path object
+     */
+    private static org.onosproject.tetopology.management.api.link.UnderlayPath
+                    yang2TeSubsystemUnderlayPath(TeLinkAttributes yangLinkAtrr) {
+        checkNotNull(yangLinkAtrr, E_NULL_YANG_TELINK_CONFIG);
+
+        org.onosproject.tetopology.management.api.link.UnderlayPath teUnderlay =
+                new org.onosproject.tetopology.management.api.link.UnderlayPath();
+
+        teUnderlay.setProtectionType(yangLinkAtrr.underlay().underlayProtectionType());
+
+        if (yangLinkAtrr.underlay().underlayPrimaryPath() != null) {
+            teUnderlay = yang2TeSubsystemUnderlayPrimaryPath(teUnderlay,
+                                    yangLinkAtrr.underlay().underlayPrimaryPath());
+        }
+
+        if (yangLinkAtrr.underlay().underlayBackupPath() != null) {
+            teUnderlay = yang2TeSubsystemUnderlayBackupPaths(teUnderlay,
+                    yangLinkAtrr.underlay().underlayBackupPath());
+        }
+
+        if (yangLinkAtrr.underlay().underlayTrailSrc() != null) {
+            teUnderlay.setTrailSrc(new TerminationPointKey(
+                                            KeyId.keyId(yangLinkAtrr.underlay().underlayTrailSrc()
+                                                            .networkRef().uri().toString()),
+                                            KeyId.keyId(yangLinkAtrr.underlay().underlayTrailSrc()
+                                                            .nodeRef().uri().toString()),
+                                            KeyId.keyId(yangLinkAtrr.underlay().underlayTrailSrc()
+                                                            .tpRef().uri().toString())));
+        }
+
+        if (yangLinkAtrr.underlay().underlayTrailDes() != null) {
+            teUnderlay.setTrailDes(new TerminationPointKey(
+                                            KeyId.keyId(yangLinkAtrr.underlay().underlayTrailDes()
+                                                            .networkRef().uri().toString()),
+                                            KeyId.keyId(yangLinkAtrr.underlay().underlayTrailDes()
+                                                            .nodeRef().uri().toString()),
+                                            KeyId.keyId(yangLinkAtrr.underlay().underlayTrailDes()
+                                                            .tpRef().uri().toString())));
+        }
+
+        return teUnderlay;
+    }
+
+    private static TeLink yang2TeLinkAttributes(TeLinkAttributes yangLinkAtrr,
+                                                State opState) {
+        TeLink te = new TeLink(yangLinkAtrr.linkIndex());
+        if (yangLinkAtrr.name() != null) {
+            te.setName(yangLinkAtrr.name());
+        }
+        if (yangLinkAtrr.adminStatus() != null) {
+            te.setAdminStatus(EnumConverter.yang2TeSubsystemAdminStatus(
+                                                yangLinkAtrr.adminStatus()));
+        }
+        if (opState != null && opState.operStatus() != null) {
+            te.setOpStatus(EnumConverter.yang2TeSubsystemOpStatus(
+                                             opState.operStatus()));
+        }
+        if (yangLinkAtrr.accessType() != null) {
+            te.setAccessType(yang2TeSubsystemAccessType(
+                                 yangLinkAtrr.accessType()));
+        }
+        if (yangLinkAtrr.linkProtectionType() != null) {
+            te.setLinkProtectionType(yang2TeSubsystemLinkProtectionType(
+                                         yangLinkAtrr.linkProtectionType()));
+        }
+        if (yangLinkAtrr.maxLinkBandwidth() != null) {
+            te.setMaxLinkBandwidth(yangLinkAtrr.maxLinkBandwidth());
+        }
+        if (yangLinkAtrr.maxResvLinkBandwidth() != null) {
+            te.setMaxResvLinkBandwidth(yangLinkAtrr.maxResvLinkBandwidth());
+        }
+        te.setTeDefaultMetric(yangLinkAtrr.teDefaultMetric());
+        te.setIsAbstract(yangLinkAtrr.isAbstract());
+        if (yangLinkAtrr.teSrlgs() != null) {
+            List<Long> srlgs = Lists.newArrayList();
+            for (Srlg srlgConfigYang : yangLinkAtrr.teSrlgs().value()) {
+                srlgs.add(srlgConfigYang.uint32());
+            }
+            te.setTeSrlgs(srlgs);
+        }
+        if (yangLinkAtrr.externalDomain() != null) {
+            te.setExternalDomain(new ExternalDomain(
+                    KeyId.keyId(yangLinkAtrr.externalDomain()
+                                    .remoteTeNodeId().toString()),
+                    KeyId.keyId(yangLinkAtrr.externalDomain()
+                                    .remoteTeLinkTpId().toString()),
+                    yangLinkAtrr.externalDomain().plugId()));
+        }
+        if (yangLinkAtrr.underlay() != null) {
+            te.setUnderlayPath(yang2TeSubsystemUnderlayPath(yangLinkAtrr));
+        }
+        if (yangLinkAtrr.unreservedBandwidth() != null) {
+            List<org.onosproject.tetopology.management.api.link.UnreservedBandwidth>
+                    unreservedBandwidths = Lists.newArrayList();
+            for (UnreservedBandwidth urBwYang : yangLinkAtrr.unreservedBandwidth()) {
+                org.onosproject.tetopology.management.api.link.UnreservedBandwidth unResBw =
+                        new org.onosproject.tetopology.management.api.link.UnreservedBandwidth(
+                                urBwYang.priority(),
+                                urBwYang.bandwidth());
+                unreservedBandwidths.add(unResBw);
+            }
+            te.setUnreservedBandwidths(unreservedBandwidths);
+        }
+        return te;
+    }
+
+    private static LinkProtectionType
+        yang2TeSubsystemLinkProtectionType(LinkProtectionTypeEnum linkProtectionType) {
+        switch (linkProtectionType) {
+        case ENHANCED:
+            return LinkProtectionType.ENHANCED;
+        case EXTRA_TRAFFIC:
+            return LinkProtectionType.EXTRA_TRAFFIC;
+        case SHARED:
+            return LinkProtectionType.SHARED;
+        case UNPROTECTED:
+            return LinkProtectionType.UNPROTECTED;
+        case YANGAUTOPREFIX1_FOR_1:
+            return LinkProtectionType.YANGAUTOPREFIX1_FOR_1;
+        case YANGAUTOPREFIX1_PLUS_1:
+            return LinkProtectionType.YANGAUTOPREFIX1_PLUS_1;
+        default:
+            return null;
+        }
+    }
+
+    private static org.onosproject.tetopology.management.api.link.TeLinkAccessType
+        yang2TeSubsystemAccessType(TeLinkAccessType accessType) {
+        switch (accessType.enumeration()) {
+        case MULTI_ACCESS:
+            return org.onosproject.tetopology.management.api.link.TeLinkAccessType.MULTI_ACCESS;
+        case POINT_TO_POINT:
+            return org.onosproject.tetopology.management.api.link.TeLinkAccessType.POINT_TO_POINT;
+        default:
+            return null;
+        }
+    }
+
+    /**
+     * Link object conversion from YANG to TE Topology subsystem.
+     *
+     * @param yangLink YANG link object
+     * @param networkId YANG networkId object
+     * @return TE subsystem link object
+     */
+    public static org.onosproject.tetopology.management.api.link.NetworkLink
+            yang2TeSubsystemLink(Link yangLink, NetworkId networkId) {
+        checkNotNull(yangLink, E_NULL_YANG_TELINK);
+
+        org.onosproject.tetopology.management.api.link.DefaultNetworkLink link =
+                new org.onosproject.tetopology.management.api.link.DefaultNetworkLink(
+                        KeyId.keyId(yangLink.linkId().uri().toString()));
+
+        if (yangLink.supportingLink() != null) {
+            List<NetworkLinkKey> spLinkIds = Lists.newArrayList();
+            for (SupportingLink yangSpLink : yangLink.supportingLink()) {
+                NetworkLinkKey linkKey = new NetworkLinkKey(KeyId.keyId(yangSpLink.networkRef().uri().toString()),
+                                                            KeyId.keyId(yangSpLink.linkRef().uri().toString()));
+                spLinkIds.add(linkKey);
+            }
+            link.setSupportingLinkIds(spLinkIds);
+        }
+
+        if (yangLink.source() != null) {
+            TerminationPointKey source = new TerminationPointKey(
+                                                 KeyId.keyId(networkId.uri().toString()),
+                                                 KeyId.keyId(yangLink.source().sourceNode().uri().toString()),
+                                                 KeyId.keyId(yangLink.source().sourceTp().uri().toString()));
+            link.setSource(source);
+        }
+
+        if (yangLink.destination() != null) {
+            TerminationPointKey destination = new TerminationPointKey(
+                                                      KeyId.keyId(networkId.uri().toString()),
+                                                      KeyId.keyId(yangLink.destination().destNode().uri().toString()),
+                                                      KeyId.keyId(yangLink.destination().destTp().uri().toString()));
+            link.setDestination(destination);
+        }
+
+        if (yangLink.yangAugmentedInfoMap() != null && !yangLink.yangAugmentedInfoMap().isEmpty()) {
+
+            AugmentedNtLink yangLinkAugment =
+                    (AugmentedNtLink) yangLink.yangAugmentedInfo(AugmentedNtLink.class);
+            if (yangLinkAugment != null &&
+                    yangLinkAugment.te() != null &&
+                    yangLinkAugment.te().config() != null) {
+                TeLinkAttributes yangLinkAtrr =
+                        yangLinkAugment.te().config().teLinkAttributes();
+                if (yangLinkAtrr != null && yangLinkAtrr.linkIndex() != null) {
+                    TeLink te = yang2TeLinkAttributes(yangLinkAtrr, yangLinkAugment.te().state());
+                    link.setTe(te);
+                }
+            }
+        }
+        return link;
+    }
+
+}