Hi, The SIP RFC section "17.1.2.1 Overview of the non-INVITE Transaction" (quick link http://tools.ietf.org/html/rfc3261#section-17.1.2.1) contains this little snippet:
"For unreliable transports, requests are retransmitted at an interval which starts at T1 and doubles until it hits T2." Which would then imply for reliable transports that either retransmits should not occur or possibly that a different retransmit timing scheme should be used. I think it's safe to say the original authors intended the former otherwise they would have included the different timing scheme. The problem I've got is a UDP only SIP client that only communicates over UDP is able to connect to TCP SIP clients through a stateless proxy. UAC (UDP only) <=== UDP ==> Stateless Proxy <=== TCP ===> UAS The UAC is going to retransmit any request, in this case a MESSAGE request, if it doesn't get a response within T1. The stateless proxy is duly going to send that retransmitted request to the UAS over the reliable TCP transport. According to the SIP RFC the UAS seems to be entitled to treat the re-transmitted MESSAGE request as a new request since it can rely on the fact that SIP requests are never retransmitted over reliable transports. Has anyone encountered this particular problem and come up with a pragmatic solution? Regards, Aaron _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
