Thanks Paul and Brett!!
On Tue, Jul 15, 2014 at 8:34 PM, Paul Kyzivat <[email protected]> wrote: > On 7/15/14 7:07 AM, Brett Tate wrote: >>> >>> Can there be any case when CANCEL reached to UA2 >>> before INVITE in case od UDP? because the 100 trying >>> can be sent by proxies as well. > > > Yes, 100 is sent hop by hop. But CANCEL is itself also hop by hop. So at > each hop the cancel is only sent if a 1xx has been received from downstream. > > >> Yes (although no longer as common); as mentioned within RFC 3261 section >> 28.1, RFC 2543 did not have the same mandate as RFC 3261. >> >> "o A UA or proxy cannot send CANCEL for a transaction until it gets a >> provisional response for the request. This was allowed in RFC >> 2543 but leads to potential race conditions." > > > I guess Brett is saying that it can only happen if there is a device on the > path that supports 2543 and not 3261. I hope there are no longer any of > those deployed. > > Thanks, > Paul > > > > > _______________________________________________ > Sip-implementors mailing list > [email protected] > https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
