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Re: Framing and control-frame continuations

From: James M Snell <jasnell@gmail.com>
Date: Thu, 7 Feb 2013 15:42:38 -0800
Message-ID: <CABP7RbeJm9FciOHiQ5s_Vmzt_Hx9J=6OgjTOQMQiZEu06Nb9LA@mail.gmail.com>
To: HTTP Working Group <ietf-http-wg@w3.org>
+1 .. the minimum data size was a bit strange to me as well.

On Thu, Feb 7, 2013 at 3:39 PM, David Morris <dwm@xpasc.com> wrote:
>
>
> On Thu, 7 Feb 2013, Martin Thomson wrote:
>
>> One potential concern with this is that the opaque id is too small. We
>> haven't discussed this, but the current design relies on the fact that
>> stream identifiers are not reused. A 16 bit id would lead to connections
>> being rendered useless very quickly. Jeff mentioned that even at 31 bits,
>> this happens too often anyway.
>>
>> That could mean that we need to consider other options anyway, but I
>> thought the information useful to surface, regardless.
>
> I was concerned abut the 16bit Opaque ID as well, it seems small to me.
>
> I also noted a comment when this frame header was suggested that frame
> data must be a minimum of 16 bits. I'm perhaps not yet aware of the
> bigger picture, but I don't understand that constraint. But it is
> a desire to maintain 64bit alignment, then just expand the ID and remove
> the 16 bit minimum constraing.
>
>> On Feb 7, 2013 1:53 PM, "James M Snell" <jasnell@gmail.com> wrote:
>>
>> > On Wed, Feb 6, 2013 at 3:47 AM, Amos Jeffries <squid3@treenet.co.nz>
>> > wrote:
>> > [snip]
>> > >
>> > > The Frame format:
>> > >
>> > >         0                   1
>> > >         0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5
>> > >        +-+-+-----------+---------------+
>> > >        |F|C|  type     |               |
>> > >        +-+-+-----------+               +
>> > >        |        Frame Length (24)      |
>> > >        +-------------------------------+
>> > >        |       opaque ID (16)          |
>> > >        +-------------------------------+
>> > >        |     Frame Data (16...N)       |
>> > >        +-------------------------------+
>> > >
>> >
>> > +1 ... I'm still unconvinced that control frames ought to be any
>> > longer than 16-bit but this seems like a reasonable compromise and
>> > workable format.
>> >
>> > - James
>> >
>> >
>>
>
Received on Thursday, 7 February 2013 23:43:25 GMT

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