Synchronize transaction for 2 IS


we make two Integration Server that one Integration Server is for composite business process and the other Integration Server for atomic process (back end system). So the idea is separate about composite service and atomic service, and the composite IS always calling the atomic IS for provisioning to back end system, because all of back end system, we put in the atomic IS.

So, here the issue, what best practice for the composite IS calling the atomic IS? we come with three type solution :

  1. using remote invoke,
  2. using broker with publishAndReply
  3. using web service for calling service in the atomic IS

Is there suggest which one that we must use? And which in three type solution that have best benchmark for one IS that calling the other IS?

As note, transaction that we have is about 10 tps.
Thanks in advance.