487 can be used in any dialog creating request such as SUBSCRIBE as well. The best solution that I can think of SDP in 487 is that UA (entity) generating dialog terminating response must not add SDP in that response (dialog terminating responses). If somehow SDP is present in such responses, it must be ignored. Presence of SDP in such response is not restricted in any rfc (as per as I know) but it doesn't really make any sense. It rather add bit extra n/w traffics.
Thanks and regards Nabam Serbang -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Somesh S. Shanbhag Sent: Monday, January 12, 2009 5:10 PM To: Alex Balashov Cc: [email protected] Subject: Re: [Sip-implementors] SDP payload in 487. The max motive I could think of is one will get to know the capabilities if 487 has answer SDP and also there might be remote possibility that the answering with SDP in 487, I doubt if user is opening media channel, in which case, it allows caller to play some terminating announcements ( don't know which application might use this concept ) -Somesh * Please dont take the print out of this e-mail unless its absolutely necessary * -----Original Message----- From: Alex Balashov [mailto:[email protected]] Sent: Monday, January 12, 2009 4:42 PM To: Somesh S. Shanbhag Cc: [email protected] Subject: Re: [Sip-implementors] SDP payload in 487. What, do you suppose, is the motive? This is coming from a Squire signaling agent. Somesh S. Shanbhag wrote: > RFC wont restrict a user from not sending SDP in 487 and even if he does > that it wont be useful. Yes, you can send SDP in 487. > > -Somesh > > -----Original Message----- > From: Alex Balashov [mailto:[email protected]] > Sent: Monday, January 12, 2009 4:37 PM > To: Somesh S. Shanbhag > Cc: [email protected] > Subject: Re: [Sip-implementors] SDP payload in 487. > > I understand that it doesn't really serve any purpose. > > Should it be there at all? > > Somesh S. Shanbhag wrote: > >> 487 Request Terminated must be for INVITE transaction. >> and since the transaction was not successful, even if the SDP is > present >> we need to ignore it. >> >> -Somesh >> >> -----Original Message----- >> From: [email protected] >> [mailto:[email protected]] On Behalf Of >> Alex Balashov >> Sent: Monday, January 12, 2009 4:30 PM >> To: [email protected] >> Subject: [Sip-implementors] SDP payload in 487. >> >> I am getting an SDP payload in a 487 Request Terminated message in >> response to a CANCEL (first a 200 OK, then a 487). >> >> Is this allowed? >> > > -- Alex Balashov Evariste Systems Web : http://www.evaristesys.com/ Tel : (+1) (678) 954-0670 Direct : (+1) (678) 954-0671 Mobile : (+1) (678) 237-1775 _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
