3.6.6 Timer Events

  • Article

When the timer described in section 3.6.2.1 fires, the SIP proxy can destroy the key for which the timer was started. The SIP proxy SHOULD then reject all requests that contain an HMAC generated with the destroyed key with a 481 Call Leg Does Not Exist response, as described in section 3.6.5.1.<25> However, if the SIP proxy implements the extensions for dialog state recovery, as described in section 3.7, it MUST follow the procedure defined there to send a 430 Flow Failed or a 481 Call Leg Does Not Exist response.<26>