Topology Hiding stores the IP/Domain from the outbound message Via header and then removes the Via header. When the inbound message is received, Topology Hiding puts the stored IP/Domain in a Via header and adds the header to the inbound message. This scenario occurs in the following settings:
If Trunk and Call server support Via header format RFC 3261, Avaya SBC must be configured for RFC3261.
If the Service provider or Call server are configured for RFC 2543 Via header support, then Interworking profile must be configured with RFC 2543 support for Via header format. If you configure Via header format that is not inline with the far-end server support, calls will fail.
