Ping succeeds across the network even when there is no association with router interface.

Steps to reproduce:

1.Created 4 Networks.
Net1, Net2,Net3 and Net4.
2.created 2 Router interfaces (Router1 and Router2).
3.Connected Router1 with Net1 & Net3
4.Connected Router2 with Net2 & Net4
5 Created 4 Vm instances on each network.
VM1 instance - net1
VM2 instance - net2
VM3 instance - net3
VM4 instance - net4
6. Now,ping should happen only between VM1 instance and VM3 instance.
7.But , have observed that ping happens even between VM1 -VM2, VM1-VM4 as well, which is incorrect.

This issue is consistently reproducible with above steps.

Distribution used:
https://nexus.opendaylight.org/content/groups/public/org/opendaylight/integration/distribution-karaf/0.5.0-Boron/distribution-karaf-0.5.0-Boron.tar.gz

Enevironment Details:
1.Open stack mitaka setup with 1 control and 1 compute node.
2.ODL controller 3 node setup.