Hi, I agree with Paul that the header can be ignored; however the header is registered with IANA and is discussed within RFC 3261.
It looks like the header is only defined for responses (although Table 2 may be incomplete). RFC 3261 may contain better quotes to ignore the header and continue processing the message; however the section 7.3.2 quote appears to apply good enough within this situation. Section 7.3.2: "If a header field appears in a message not matching its category (such as a request header field in a response), it MUST be ignored." Section 8.2.1: "If a UAS does not understand a header field in a request (that is, the header field is not defined in this specification or in any supported extension), the server MUST ignore that header field and continue processing the message." > -----Original Message----- > From: sip-implementors-boun...@lists.cs.columbia.edu [mailto:sip- > implementors-boun...@lists.cs.columbia.edu] On Behalf Of Paul Kyzivat > Sent: Tuesday, February 16, 2016 12:39 PM > To: sip-implementors@lists.cs.columbia.edu > Subject: Re: [Sip-implementors] authentication-info header > > On 2/16/16 11:19 AM, Jing Jiang wrote: > > Recently, we saw a case that a server (Asterisk) sent our client an > authentication-info header in its "bye" message, but our SIP device is just a > client and never challenges the server. Our client doesn't expect this header > so the "bye" request was declined. > > What is the right behavior for the client? The client should ignore the > unexpected header and process others? > > Yes, ignore it. That header field has not been registered with IANA as a > valid header field. But we don't expect implementations to distinguish > between undefined headers and headers that are defined in extensions that the > server doesn't support. Unknown header fields are to be ignored. > > Thanks, > Paul > > > Thanks, > > Jing _______________________________________________ Sip-implementors mailing list Sip-implementors@lists.cs.columbia.edu https://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
