RFC 3261 section 3 indicates to use RFC 2119's interpretation of MAY. 5. MAY This word, or the adjective "OPTIONAL", mean that an item is truly optional. One vendor may choose to include the item because a particular marketplace requires it or because the vendor feels that it enhances the product while another vendor may omit the same item. An implementation which does not include a particular option MUST be prepared to interoperate with another implementation which does include the option, though perhaps with reduced functionality. In the same vein an implementation which does include a particular option MUST be prepared to interoperate with another implementation which does not include the option (except, of course, for the feature the option provides.)
> -----Original Message----- > From: sip-implementors-boun...@lists.cs.columbia.edu [mailto:sip- > implementors-boun...@lists.cs.columbia.edu] On Behalf Of Leo Leo > Sent: Friday, July 01, 2011 8:49 AM > To: Johnson, Michael A; sip-implementors@lists.cs.columbia.edu > Subject: Re: [Sip-implementors] Re-Invite codec renegotiation. > > Hi, > > Just adding some information, RFC3261 allows sending re-invite without > SDP body. I don't think this is a good idea because the UA witch sends > a re-invite with a new renegotiation should present its alternatives. I > remmember that RFC says 'MAY', witch preciselly means it's possible but > it's not a good idea. > > > Section 14.1 UAC Behavior (page 86) > > (...)It is important to note that the full > description of the session, not just the change, is sent. This > supports stateless session processing in various elements, and > supports failover and recovery capabilities. Of course, a UAC MAY > send a re-INVITE with no session description, in which case the > first > reliable non-failure response to the re-INVITE will contain the > offer > (in this specification, that is a 2xx response) > _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
