Re: Deadlocking in the transport

Ian Swett <ianswett@google.com> Wed, 17 January 2018 22:37 UTC

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From: Ian Swett <ianswett@google.com>
Date: Wed, 17 Jan 2018 17:36:45 -0500
Message-ID: <CAKcm_gN2s2c9Uw86Ppb0yGLHXnahSfLBaWG7VoX31Nvut_hBAA@mail.gmail.com>
Subject: Re: Deadlocking in the transport
To: Jana Iyengar <jri@google.com>
Cc: Martin Thomson <martin.thomson@gmail.com>, QUIC WG <quic@ietf.org>, Roberto Peon <fenix@fb.com>
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+1 million

On Wed, Jan 17, 2018 at 4:43 PM, Jana Iyengar <jri@google.com>; wrote:

> We will discuss this at the interim, but one comment, inline.
>
>
>> In part, it's the ignorance of the intermediary that causes this
>> particular problem.  If the intermediary was aware of the protocol
>> details then it might be able to recognize and avoid these situations,
>> but that seems a little too much to expect of intermediaries. Ruling
>> out the entire class of intermediary that operates purely at the
>> transport layer is extremely harsh.
>>
>> What is more likely here is that we describe this situation, explain
>> that it is impossible to prevent in the presence of intermediation,
>> and explain how to kill the right streams in order to ensure forward
>> progress doesn't stall indefinitely.
>>
>
> Exactly because intermediaries make things difficult, it's important to be
> certain that the intermediary behavior we are discussing is one that
> there's a strong argument for supporting. We have spent countless cycles on
> designing around uncertain and unknown intermediary behaviors in various
> parts of the IETF, and I don't want us to recreate these boogeymen. I think
> it's reasonable to rule out classes of middleboxes if we don't have strong
> arguments for supporting them.
>
>