Hi Paul, Thanks for your response. Quoting your statement "But it makes no sense to send this unless there was a matching prior sip request with the same sip URI."
If I understood correctly the earlier request prior to CANCEL is normally a sip INVITE. And in case of INVITE has been sent with the such format in FROM header then further requests like CANCEL can send it else not. Do we have any reference on RFC that any SIP entity should not send sip >From header as like on CANCEL if INVITE has not sent with that way? BR///Rakesh On Thu, Aug 4, 2022 at 8:24 PM Paul Kyzivat <pkyzi...@alum.mit.edu> wrote: > On 8/4/22 8:11 AM, Rakesh wrote: > > Hi Team, > > > > I could see in a sip CANCEL message From Header as below > > > > From: "test" <sip:ims.test.in>;tag=3bbb9483d215d830c635372f8f181929 > > > > is this correct? > > Just looking at this, without regard for context, it is valid syntax. > (The userinfo portion of the sip URI is optional.) > > But it makes no sense to send this unless there was a matching prior sip > request with the same sip URI. > > Each domain is free to define the userinfo portion of its sip URIs as it > sees fit. This includes whether to support URIs with no userinfo. You > might want to consult an administrator for ims.test.in. > > Thanks, > Paul > > > Normally the From header is sip:user@domain > > > > As per ABNF grammar, the above one is also should not be an issue as From > > header but could let me know if I misinterpreted the ABNF grammar? > > > > BR///Rakesh > > _______________________________________________ > > 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 > _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
