IMG 1010 - SIP INFO Method - Long Call Duration Auditing
Overview:
The feature 'Long Call Duration Auditing using the SIP INFO Method' verifies whether a call is still in progress. If the IMG receives a SIP INFO request with id and tags that match an active call, a 200 OK response indicating that the call is still in progress will be sent from the IMG. If the IMG receives a SIP INFO request with id and tags that do not match an active call, then a response of '481 Call Leg/Transaction Does Not Exist' is sent from the IMG. The initiator of the SIP message will then be able to determine if call is up or not. Below are call flows for each scenario.
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