You have some cluster traffic for replication/synchronization and call signaling in between,
but thats not that much.
Further it would be interesting what you are going to use it for, mra, b2b, jg, interop, ...
as well as the most interesting part, how much external traffic do you expect?
In most cases on a pure expressway I would not expect that much media traffic in between
peers within a cluster. In a failover case for example for b2b you would need the full amount
of used external traffic in between the cluster peers.
