Andrew, You cannot send a response to a response
I would suggest the following handling: when Content-Type is not present, assume application/sdp and try to parse the body (or at least check if it starts with 'v='). If the check fails, see if 'Required: 100rel' is present; if so you will need to send a PRACK. It would probably be best to generate some dummy SDP, without any media If '100rel' is not required, you can safely ignore the response anyway, since it is provisional. Any SDP would (have to) be repeated in the final response. If the INVITE was forwarded transaction statefully, the 183 will serve to stop retransmissions Regards, Jeroen ----- Original Message ----- From: "Sweeney, Andrew (Andrew)" <[EMAIL PROTECTED]> To: "'Attila Sipos'" <[EMAIL PROTECTED]>; "Sweeney, Andrew (Andrew)" <[EMAIL PROTECTED]>; <[email protected]> Sent: Wednesday, February 08, 2006 2:15 PM Subject: Re: [Sip-implementors] How to handle a 18x response with amissin gheader > Thanks, But I thought it was invalid to send a response to a response. I > will go back through the RFC and check again. I guess I could always send > a 487 as well. > > > -----Original Message----- > From: Attila Sipos [mailto:[EMAIL PROTECTED] > Sent: Wednesday, February 08, 2006 4:10 AM > To: Sweeney, Andrew (Andrew); [email protected] > Subject: RE: [Sip-implementors] How to handle a 18x response with a > missingheader > > > > This is difficult. No doubt you are asking this > beacuse there is no explicit statement (as far as I > can see) regarding your scenario in RFC3261. > > The RFC does however state that "The Content-Type header > field MUST be present if the body is not empty.". > > I guess there are a variety of approaches: > 1. reject it with 400 Bad Request > 2. reject it with 415 Unsupported Media Type > and say what you can accept with an Accept header > (like what it says in 8.2.3 Content Processing) > 3. assume that it's "application/sdp" and try > to parse it as such. If you fail to parse it, > return with 415 Unsupported Media Type. > > Maybe the 2nd is the most technically correct since > it will at least tell the other people that you don't > understand the one of the Content headers. > > The 3rd option would probably give the most interop > but this is somewhat encouraging others to be a bit sloppy. > > With things like this, it's simply best to tell the > makers of the offending UA that they're not compliant > with one of the basic mandatory requirements of RFC3261. > > Regards, > Attila > > > >>> -----Original Message----- >>> From: [EMAIL PROTECTED] >>> [mailto:[EMAIL PROTECTED] Behalf >>> Of Sweeney, >>> Andrew (Andrew) >>> Sent: 07 February 2006 22:05 >>> To: '[email protected]' >>> Subject: [Sip-implementors] How to handle a 18x response with a >>> missingheader >>> >>> >>> >>> >>> I have received a 183 message with a content length but >>> no content type. What is the correct procedure for rejecting >>> this message or dropping >>> the entire dialog? >>> >>> Thanks >>> _______________________________________________ >>> 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 _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
