System and method for transporting a call in a telecommunication network

A signaling processor processes a first message to select a TDM connection for the call and transfers a second message indicating the selected TDM connection. The interworking unit receives the second message and user communications for the call in a packet format, converts the user communications from the packet format to a TDM format, and transfers the user communications in the TDM format over the selected TDM connection. The interworking unit monitors the user communications for a trigger after call set-up and during the call, and if the trigger is detected, transfers a third message indicating the trigger. The signaling processor receives and processes the third message to select routing information for routing the call to a service platform and transfers a fourth message indicating the selected routing information to route the call to the service platform.