Added tests for ipv6 hosts and refactored Comcast fabric.

Change-Id: I151564afee471cac5d3a3ff48b65dff609b13c23
diff --git a/TestON/tests/USECASE/SegmentRouting/SRRouting/SRRouting.py b/TestON/tests/USECASE/SegmentRouting/SRRouting/SRRouting.py
index e452901..b3d61f3 100644
--- a/TestON/tests/USECASE/SegmentRouting/SRRouting/SRRouting.py
+++ b/TestON/tests/USECASE/SegmentRouting/SRRouting/SRRouting.py
@@ -17,6 +17,22 @@
                                 routers=0,
                                 ipv4=1,
                                 ipv6=0,
-                                description = "Ping between all ipv4 hosts in
-                              the topology")
+                                description = "Ping between all ipv4 hosts in the topology")
+
+    def CASE2( self, main ):
+        """
+        Ping between all ipv6 hosts in the topology.
+        """
+
+        from tests.USECASE.SegmentRouting.SRRouting.dependencies.SRRoutingTest import SRRoutingTest
+
+        SRRoutingTest.runTest( main,
+                                test_idx = 2,
+                                onosNodes = 3,
+                                dhcp=0,
+                                routers=0,
+                                ipv4=0,
+                                ipv6=1,
+                                description = "Ping between all ipv6 hosts in the topology")
+