Re: 3.3.1 Frame Header: Purpose of 1-bit reserved field?

Mark Nottingham <mnot@mnot.net> Sat, 13 April 2013 06:50 UTC

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From: Mark Nottingham <mnot@mnot.net>
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Date: Sat, 13 Apr 2013 16:48:22 +1000
Cc: "Brian Raymor (MS OPEN TECH)" <Brian.Raymor@microsoft.com>, "'ietf-http-wg@w3.org'" <ietf-http-wg@w3.org>
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To: "Adrien W. de Croy" <adrien@qbik.com>
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Subject: Re: 3.3.1 Frame Header: Purpose of 1-bit reserved field?
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Looking at the minutes from Tokyo, this was originally for control vs. data (as in SPDY).

I think there's been some discussion about discarding the control bit; OTOH, if people are going to define extension frames, it'd be nice for intermediaries to know whether they count against flow control without having to understand their semantics...

Cheers,


On 13/04/2013, at 3:43 PM, Adrien W. de Croy <adrien@qbik.com> wrote:

> 
> future proofing?  E.g. if we need to move to another format or size for stream ID?
> 
> 
> ------ Original Message ------
> From: "Brian Raymor (MS OPEN TECH)" <Brian.Raymor@microsoft.com>
> To: "'ietf-http-wg@w3.org'" <ietf-http-wg@w3.org>
> Sent: 13/04/2013 12:48:46 p.m.
> Subject: 3.3.1 Frame Header: Purpose of 1-bit reserved field?
>> 3.3.1. Frame Header
>> 
>>  |R| Stream Identifier (31) |
>> 
>> 
>>   R: A reserved 1-bit field. The semantics of this bit are not defined.
>> 
>> I was curious about the purpose for the 1-bit reserved field. Can it be deleted and the Stream Identifier increased to 32 bits?
>> 
>> https://github.com/http2/http2-spec/issues/67
>> 
>> 
>> Brian Raymor
>> Senior Program Manager
>> Microsoft Open Technologies, Inc.
>> A subsidiary of Microsoft Corporation
>> 
>> 
>> 
> 
> 

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