Via headers are only used to route responses back. BYE is a new request, which uses the Record-Route and Contact headers if they exist. There have been some changes and clarifications to how this works, so you should refer to the latest bis draft at:
http://www.ietf.org/internet-drafts/draft-ietf-sip-rfc2543bis-04.txt John Hearty Level3 -----Original Message----- From: Lei Liang [mailto:[EMAIL PROTECTED]] Sent: Tuesday, October 16, 2001 4:31 AM To: sip implementation mail list Subject: [Sip-implementors] MUST the callee or caller sends BYE with VIA header? HI, everybody, i saw the example in rfc2543 that when callee sends BYE to terminate the call, it uses via header. does it copy the header form previous request received or response sent? MUST it add the via header in? because the rfc said the BYE unlikely traverse the same proxies as the original INVITE, why it still uses the via header? by the way, if a callee response a request, MUST it get the back route from the request via header if exists? it looks that via header's priority is higher than Contact header when the user agent is trying to get the route set, isn't? any information is deeply appreciated. thanks. lei here is the example of BYE in rfc2543: C->S: BYE sip:[EMAIL PROTECTED] SIP/2.0 Via: SIP/2.0/UDP kton.bell-tel.com From: A. Bell <sip:[EMAIL PROTECTED]> To: T. A. Watson <sip:[EMAIL PROTECTED]> ;tag=37462311 Call-ID: [EMAIL PROTECTED] CSeq: 2 BYE _______________________________________________ Sip-implementors mailing list [EMAIL PROTECTED] http://lists.cs.columbia.edu/mailman/listinfo/sip-implementors
