Ansuman, Normally, a SIP client receiving a 200 OK to REGISTER without any Contacts will interpret this as "no contacts registered", i.e. registration failure. Normally it would only occur after a de-registration. However, there is nothing to stop a client from sending an INVITE when it is not registered (at least not in all environments). No mandatory procedure defined.
Regards, Jeroen Ansuman Mukherjee wrote: > Hello All, > I'm facing an unique issue with a specific SIP Server in > here. The issue is - the' Contact' header is always missing in the 200-OK > message sent in reply to the initial REGISTER message. However when I try > with > X-Lite with this Server, it works properly even if the contact header is > missing > in the 200-OK. > As per my understanding of RFC3261 Section 10.3, it > is mandatory for the Server to send a contact info in the 200-OK response to > the > REGISTER request. But what I'm failing to understand is what happens if there > is > no contact header present in the 200-OK message? How is a SIP UA expected to > behave in such scenario? Is there any mandate to address such a scenario - or > is it left onto the SIP client vendor to implement there own customisation? > Awaiting your valuable response. > > Thanks, > Ansuman > > > _________________________________________________________________ > Download the latest version of Windows Live Messenger NOW! > http://get.live.com/en-ie/messenger/overview > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors > > _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
