Re: p1: Via and gateways

David Morris <dwm@xpasc.com> Sat, 20 April 2013 07:22 UTC

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Date: Sat, 20 Apr 2013 00:21:52 -0700 (PDT)
From: David Morris <dwm@xpasc.com>
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Subject: Re: p1: Via and gateways
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On Sat, 20 Apr 2013, Mark Nottingham wrote:

> 
> p1 Section 2.3 says:
> 
> > However, an HTTP-to-HTTP gateway that wishes to interoperate with
> > third-party HTTP servers must conform to HTTP user agent requirements
> > on the gateway's inbound connection and must implement the Connection
> > (Section 6.1) and Via (Section 5.7.1) header fields for both
> > connections.
> 
> This means that accelerators and CDNs MUST generate a Via header on the
> outbound connection. This isn't widely practiced, and I'm not sure it's
> necessary. Comments?

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.