RFC 3398, "Integrated Services Digital Network (ISDN) User Part (ISUP) to Session Initiation Protocol (SIP) Mapping", December 2002Source of RFC: sipping (rai)
Errata ID: 2580
Status: Held for Document Update
Reported By: Stephen James
Date Reported: 2010-10-19
Held for Document Update by: Gonzalo Camarillo
Date Held: 2011-01-27
Section 8.1.3 says:
Item 6. The gateway also sends a CANCEL message to the SIP node to terminate any initiation attempts.
It should say:
Drop this statement. Section 8.1.3 item 6 should be updated to "The gateway also sends a CANCEL message to the SIP node to terminate the initiation attempt if a provisional response has been received." The situation illustrated in section 8.1.3 does not distinguish the "provisional response received" case from the "provisional response not received" case, so the commentary should cover both cases. (The specific example diagrammed shows the "no provisional response received" case.) A similar change should be made to section 8.1.4 item 7, "The REL will trigger a CANCEL request to the SIP node if a provisional response has been received." A similar change should be made to section 8.1.7 item 7, "Upon receipt of a REL message before an INVITE final response, the gateway will send a CANCEL towards the SIP node if a provisional response has been received.
No CANCEL is sent on INVITE transaction timeout. This is per 3261 "If no provisional response has been received, the CANCEL request MUST NOT be sent; rather, the client MUST wait for the arrival of a provisional response before sending the request."