> Hi Alll, > > I have a simple doubt about CSeq number in an out-going message > > Is it ok to have the same CSeq number for a REGISTER request and > SUBSCRIBE request.. ????
Yes. > It's been mentioned in 8.1.3.5 that CSeq number must be increased upon > failure to earlier request.. This does not seem to apply for different > set of requests from the same entity. But nowhere else > mentioned that it > must be increased for all the outgoing messages from a SIP entity. RFC3261: Section 4 contains: CSeq or Command Sequence contains an integer and a method name. The CSeq number is incremented for each new request within a dialog and is a traditional sequence number. Section 20.16 contains: The CSeq header field serves to order transactions within a dialog, to provide a means to uniquely identify transactions, and to differentiate between new requests and request retransmissions. The subscription presumably establishes a dialog, so all subsequent reSUBSCRIBEs must maintain CSeq continuity, as normal for in-dialog requests. The rules for registration are slightly different to other methods, since registration doesn't establish a dialog, but must still maintain Call-ID and CSeq continuity. See section 10.2 for the details. There is no coupling between the CSeqs for registration and dialogs, or indeed between dialogs. Regards, Michael Procter _______________________________________________ Sip-implementors mailing list [email protected] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
