It's depend upon the implementation. SIP environment can be used in which client register in which registrar is used. In case of SIP proxy endpoint of the IP need to configure from where traffic is expected. In this case registration is not required.
Thanks and Regards Dheeraj Kumar Sent from iPhone > On 19-Oct-2016, at 11:36 AM, Adnan Aziz <chaudhryad...@gmail.com> wrote: > > Hi Everyone, > I have couple of basic questions regarding SIP session setup > > 1) is it compulsory for UAC to REGISTER to SIP server before session setup? > 2) does SIP server checks if the UAC is REGISTERED to the SIP server if it > has received an INVITE request from a UAC? If yes then how SIP server > handle to the INVITE requests from unregistered UAC? > > Regards, > Adnan Aziz > _______________________________________________ > Sip-implementors mailing list > Sip-implementors@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors