Re: p1: Via and gateways

Mark Nottingham <mnot@mnot.net> Sat, 20 April 2013 07:56 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Subject: Re: p1: Via and gateways
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On 20/04/2013, at 5:21 PM, David Morris <dwm@xpasc.com> 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/