Hi Anjan, CANCEL can be send only after receiving any provisional response (1xx including 100) and before receiving the final response of INVITE. Refer the section-9, RFC-3261:
" If no provisional response has been received, the CANCEL request MUST NOT be sent; rather, the client MUST wait for the arrival of a provisional response before sending the request. If the original request has generated a final response, the CANCEL SHOULD NOT be sent, as it is an effective no-op, since CANCEL has no effect on requests that have already generated a final response. " Thanks, Alok Tiwari On Wed, Dec 31, 2014 at 12:03 PM, Anjan Naik <anjankumarn...@gmail.com> wrote: > HI All, > > I have a query regarding Cancelling a call before Provisional response. > > As per RFC 3261, CANCEL can be sent after a provisional response (1xx > response other than 100) receivecd. Suppose i make a call > steps: > 1) INIVITE sent to Callee > 2) Callee didn't send anything > > Now i want to cancell the call. > What shold be call flow ? > > Thanks, > Anjan > _______________________________________________ > Sip-implementors mailing list > Sip-implementors@lists.cs.columbia.edu > https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors > -- Alok Tiwari | Consultant GlobalLogic P +91.120.406.2000 x 2477 M +91.991.034.7139 S alo...@globallogic.com <http://alok.t_globallogic.com/> www.globallogic.com <http://www.globallogic.com/> http://www.globallogic.com/email_disclaimer.txt _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
