On 20/04/2013, at 5:21 PM, David Morris <dwm@xxxxxxxxx> wrote: > > I don't care about MUST, but I think the Via header can be useful for > problem determination. A smart content server could also adjust for > a detected accelerator and/or transcoder ... perhaps by avoiding > optimizations dependant on a direct connection and byte/byte transfer > between the client and the server. > > So I'm very much in favor of keeping the Via: header. Definitely not talking about getting rid of it. The (only, specific) point here is whether a gateway that doesn't add Via to responses should be called non-conformant. Personally, I think it should be a MUST for proxies, in both directions. However, for a gateway, it either shouldn't be a requirement at all (for responses), or it should be a SHOULD with a get-out clause for reasons of security (along with a note that they'll need to accept responsibility for any issues caused by omitting Via). Still should probable be a MUST for requests from gateways. Cheers, -- Mark Nottingham http://www.mnot.net/