Hello Guys, Different SDP in 183 and 200_OK is a protocol violation or implementation dependent?
I am seeing some previous discussions on this topic, but the answers are not quite convincing to me. I am unable to find SIP RFCs to see how this scenario is handled. 1)SIP-Server sends a SIP INVITE(offer) to SIP-SS7-Gateway 2)SIP-SS7-Gateway converts a SIP INVITE to IAM and sends IAM out 3)SIP-SS7-Gateway receives ACM (Lets say the far SS7 end opens up voice path upon ACM rather than ANM, may be a kind of announcement server. I guess, i can calls this Early-Media) 4)SIP-SS8-Gateway converts ACM into 183 sends 183(answer) to SIP-Server 5)SIP-Server sends back PRACK to SIP-SS7-Gateway 6)SIP-SS7-Gateway sends 200 OK (PRACK) to SIP-Server 7)SIP-SS7-Gateway receives ANM (from SS7 network perspective, the CIC is same for this call, so opening voice path after ACM or ANM makes no difference) 8)SIP-SS7-Gateway converts ANM into 200_OK and sends 200_OK(different answer) to SIP-Server ... In the step8, SIP-SS8-Gateway sends a different answer in the 200 OK for some internal reason (implementation dependent ,may be to intercept only the user's voice or etc...) PS: Please do not quote the section 13.2.1 in rfc 3261. Thanks Sam J ________________________________ _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
