Method and system for providing answer supervision in a switched

Abstract

A method and system for providing answer supervision in a switched telephone network are described. The method involves monitoring signaling links in a common channel signaling system to track call progress. If a called number is determined to be suspect with respect to providing call answer indications, the system may route calls to monitored facilities which measure the commencement of payload traffic. When payload traffic is detected, a call answer message can be sent through the signaling network to initiate billing, or call release messages may be sent in each direction to cancel the call. Both inter-network and intra-network calls can be monitored to provide answer supervision and ensure that toll calls are properly billed in accordance with actual toll facility usage.