Re: p1: Via and gateways

Mark Nottingham <mnot@mnot.net> Wed, 24 April 2013 03:29 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Date: Wed, 24 Apr 2013 13:27:45 +1000
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To: Willy Tarreau <w@1wt.eu>
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Subject: Re: p1: Via and gateways
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On 23/04/2013, at 4:43 PM, Willy Tarreau <w@1wt.eu> wrote:

> Then I would propose this addition :
> 
>   Multiple Via field values represent each proxy or gateway that has
>   forwarded the message.  Each recipient MUST append its information
>   such that the end result is ordered according to the sequence of
> -  forwarding applications.
> +  forwarding applications. A gateway MAY simply relay any existing Via
> +  header field if it does not change the HTTP version, but it MUST NOT
> +  remove it.

This is already covered further down:

> A proxy or gateway may combine an ordered subsequence of Via header field entries into a single such entry if the entries have identical received-protocol values.

The question I was raising was specific: can we relax the requirement for a gateway to add Via to responses if there isn't already one present?

--
Mark Nottingham   http://www.mnot.net/