Generic Tunnel Subsystem (ONOS-1276) and L1/L0 (OTN/ROADM)extensions (ONOS-676):
1)Initial Work for ONOS-676: OTN/ROADM (L1/L0 NE) support in ONOS by extending the device/port modeling;
  - extending device type to include L1 OTN NEs;
  - extending port type to include ODUCLT port(T-port), OCH-port(L-port), OMS-port (WDM-port);
  - more standard annotations related to OTN/ROADMs support will come from PCEP provider as well as TL1 providers;
2)Intial Work for ONOS-1276: generic Tunnel subsystem in ONOS for both packet (L3/L2) networks and optical (L1/L0) networks
  - supporting PCEP framework, which is capable of interacting with the PCEP provider;
  - supporting any other kind of tunnel provider;
  - each Tunnel is associated with at least two Labels (abstracted logical entity/Id for virtualization of physical port);
  - same type of Tunnels can be formed as a reachablity graph for other services and NB applications use;

Change-Id: I29af495f90e179e2c5d8753b76e02889a3b4355b
diff --git a/core/api/src/main/java/org/onosproject/net/tunnel/DefaultTunnelDescription.java b/core/api/src/main/java/org/onosproject/net/tunnel/DefaultTunnelDescription.java
new file mode 100644
index 0000000..432f4c6
--- /dev/null
+++ b/core/api/src/main/java/org/onosproject/net/tunnel/DefaultTunnelDescription.java
@@ -0,0 +1,93 @@
+/*
+ * Copyright 2015 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.net.tunnel;
+
+import com.google.common.base.MoreObjects;
+
+import org.onosproject.net.AbstractDescription;
+import org.onosproject.net.ConnectPoint;
+import org.onosproject.net.SparseAnnotations;
+
+/**
+ * Default implementation of immutable tunnel description entity.
+ */
+public class DefaultTunnelDescription extends AbstractDescription
+        implements TunnelDescription {
+
+    private final TunnelId  tunnelId;
+    private final ConnectPoint src;
+    private final ConnectPoint dst;
+    private final Tunnel.Type type;
+    private final boolean isBidirectional;
+
+    /**
+     * Creates a tunnel description using the supplied information.
+     *
+     * @param id          TunnelId
+     * @param src         ConnectPoint source
+     * @param dst         ConnectPoint destination
+     * @param type        tunnel type
+     * @param isBidirectional        boolean
+     * @param annotations optional key/value annotations
+     */
+    public DefaultTunnelDescription(TunnelId id, ConnectPoint src, ConnectPoint dst,
+                                  Tunnel.Type type, boolean isBidirectional,
+                                  SparseAnnotations... annotations) {
+        super(annotations);
+        this.tunnelId = id;
+        this.src = src;
+        this.dst = dst;
+        this.type = type;
+        this.isBidirectional = isBidirectional;
+    }
+
+    @Override
+    public TunnelId id() {
+        return tunnelId;
+    }
+
+    @Override
+    public ConnectPoint src() {
+        return src;
+    }
+
+    @Override
+    public ConnectPoint dst() {
+        return dst;
+    }
+
+    @Override
+    public Tunnel.Type type() {
+        return type;
+    }
+
+    @Override
+    public boolean isBidirectional() {
+        return isBidirectional;
+    }
+
+    @Override
+    public String toString() {
+        return MoreObjects.toStringHelper(this)
+                .add("tunnelId", id())
+                .add("src", src())
+                .add("dst", dst())
+                .add("type", type())
+                .add("isBidirectional", isBidirectional())
+                .toString();
+    }
+
+}