Hi - Could anyone point me to information defining whether a "183-Session progress" Informational response - MUST/SHOULD/MAY/etc. supply a "To" tag?
SIP Call traces in draft-ietf-sipping-pstn-call-flows-01.txt illustrate To tags being supplied, however, I haven't found anything definitively stating whether it must be, or is not, supplied... 183's appear to be generated by Gateways connected to ss7 networks. Upon receipt of ACM, in response to IAM from INVITE, the called GW sends 183 to establish early media [SDP supplied] for in-band tones [ring/beep/etc] from the PSTN as opposed to the UA generating the tones locally. I am having a little difficulty trying to interop with a Gateway that does not give me a To tag. This is preventing me from establishing a unique dialog and setting up calls...So, I'm looking to find out whether this is really an issue or not so I can properly address it. Best Regards, RGT - _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
