From: "Subbarayalu Subbiah" <[EMAIL PROTECTED]> i want to know ,is it possible for proxy 1 to by pass the request (since it is not processing these header) to proxy 2 ( where the actual processing is done for this header) instead of sending a 420 response.
No, if there is a Proxy-Require header, if proxy 1 does not understand an option-tag, it MUST reject the request with 420. Indeed, it is not possible for proxy 1 to do otherwise. If the implementor of proxy 1 was to desire for it to do something else, proxy 1 would have to understand the "pref" option-tag, at least enough to pass the message onward in the presence of such a Proxy-Require header. And so, since proxy 1 understands the "pref" option-tag, it would not be under the obligation to reject the request. As RFC 3841 says, a proxy is not required to *act* on these headers, even if it understands them. So the behavior you describe for proxy 1 is conformant to RFC 3841, and so proxy 1 can claim to understand the "pref" option-tag. But your example makes it clear that it is rarely useful to use "Proxy-Require: pref", because the request could easily get rejected before it arrived at the proxy that needed to understand Accept-Contact. Dale _______________________________________________ Sip-implementors mailing list [email protected] https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
