Option (a - no Contacts) is the normal practice. Option (b - Contacts w/expires=0) is legal, but might confuse some User Agent implementations.
A REGISTER which removes the contacts removes the bindings in the registrar. The 200-OK response has a Contact for each binding. If all the bindings have been removed, there is nothing to put in the Contact header. Therefore it is perfectly fine to return a 200-OK without a Contact header. If you send a REGISTER query request (no Contacts) a few seconds later, you would get back a 200-OK w/o Contacts because there are no bindings. cheers, (-:bob Robert F. Penfield Chief Software Architect Acme Packet, Inc. 71 Third Avenue Burlington, MA 01803 [EMAIL PROTECTED] ----- Original Message ----- From: "Bala Neelakantan" <[EMAIL PROTECTED]> To: "'Jeroen van Bemmel'" <[EMAIL PROTECTED]>; <[email protected]> Sent: Saturday, May 05, 2007 3:27 PM Subject: Re: [Sip-implementors] deregistration: Contact in 200 OK? >I think 200 OK for REGISTER MUST have contact header. So deregistration > should have a expires=0 in it. > > See RFC 3261, Section 10.3 > > 8. The registrar returns a 200 (OK) response. The response MUST > contain Contact header field values enumerating all current > bindings. Each Contact value MUST feature an "expires" > parameter indicating its expiration interval chosen by the > registrar. The response SHOULD include a Date header field. > > If the 200 OK doesn't have any contact, the UA could optionally consider > the > receipt of 200 OK as successful de-registration. This will enhances > interop. > > Thanks, > Neel > > >> -----Original Message----- >> From: [EMAIL PROTECTED] [mailto:sip-implementors- >> [EMAIL PROTECTED] On Behalf Of Jeroen van Bemmel >> Sent: Saturday, May 05, 2007 4:37 AM >> To: [email protected] >> Subject: [Sip-implementors] deregistration: Contact in 200 OK? >> >> Which is correct: >> >> a) 200 OK for deregister with Contact header with expires=0 in it >> b) 200 OK for deregister without any Contacts >> >> Regards, >> Jeroen >> _______________________________________________ >> 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
