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Re: #179: Relax Via MUST

From: Adrien de Croy <adrien@qbik.com>
Date: Fri, 17 Jul 2009 19:05:19 +1200
Message-ID: <4A6022AF.8030305@qbik.com>
To: Mark Nottingham <mnot@mnot.net>
CC: "Roy T. Fielding" <fielding@gbiv.com>, Henrik Nordstrom <henrik@henriknordstrom.net>, HTTP Working Group <ietf-http-wg@w3.org>

yes, I think many specific-application proxies don't put Via in, 
probably for that reason.

in fact I think many proxies also mirror the HTTP version they received 
in the request through to the next hop.

Transparent proxies are still required to insert Via?

Mark Nottingham wrote:
> In the back of my head, I've actually been thinking it would be useful 
> to note that Via is necessary for operation of some protocol features, 
> which is why there's the option for a minimal Via header, e.g. "1.1 foo".
>
> I say this because I suspect that many implementers just don't realise 
> that it has these uses. Of course, you're not going to dissuade the 
> more paranoid folks from stripping anything that looks like 
> intermediation, but oh well.
>
> Cheers,
>
>
> On 17/07/2009, at 4:40 PM, Adrien de Croy wrote:
>
>>
>> I think it might have been me that raised this issue a while back
>>
>> I agree it needs to be closed with no action.
>>
>> Taking it out breaks too much stuff.
>>
>> The original query related to customers who have unreasonable ISPs 
>> who don't want customers to run proxies to get more use out of their 
>> link, these customers didn't want there to be anything in their HTTP 
>> requests that would give away the existence of a proxy.
>>
>> I think this case is probably best handled with an option (default 
>> off) to make the proxy "stealthy", which strictly speaking makes it 
>> broken (no outbound Via).  Inbound Via is another matter and doesn't 
>> have any privacy issues.
>>
>> It's probably even less of an issue now with the prevalence of 
>> proxies for other purposes, even running on the local machine (e.g. 
>> some filtering / AV software installs a proxy for localhost).
>>
>> Thanks
>>
>> Adrien
>>
>>
>> Roy T. Fielding wrote:
>>> On Jul 16, 2009, at 5:13 PM, Mark Nottingham wrote:
>>>
>>>> I'm fine closing this with no action; IIRC the previous discussion 
>>>> was leaning towards removing the requirement.
>>>>
>>>> Others?
>>>
>>> There is no way we can remove the requirement without removing
>>> half a dozen other features.  Intermediaries that don't send
>>> Via are broken and will continue to be broken even if the
>>> requirement doesn't exist.
>>>
>>> ....Roy
>>>
>>>
>>
>> -- 
>> Adrien de Croy - WinGate Proxy Server - http://www.wingate.com
>>
>
>
> -- 
> Mark Nottingham     http://www.mnot.net/
>
>

-- 
Adrien de Croy - WinGate Proxy Server - http://www.wingate.com
Received on Friday, 17 July 2009 07:02:26 GMT

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