How TCAP CLASS Messaging Works

On-Network TCAP Query

1. Your TCAP query passes through the TNS network just as if it was bound for a LEC.
2. TNS performs the final GTT and forwards to the customer switch.
3. The MTP response is routed back to your switch through TNS STPs.
4. If another TNS customer launches a TCAP CLASS message to you, the above process is reversed.

Off-Network TCAP Query

1. Your TCAP query (such as automatic callback) passes through the TNS network, where an intermediate GTT determines the appropriate STP routing.
2. The query is directed to the LATA STP, where a final GTT determines the switch point code and final routing.
3. The response is MTP-routed back to your switch.
4. For TCAP queries launched from another LEC to you, the procedure is reversed, with the intermediate GTT performed at the LATA STP, and the final GTT performed by TNS.