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Re: [hybi] Framing take IV [why fragment]

Patrick McManus <mcmanus@ducksong.com> Wed, 04 August 2010 18:49 UTC

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From: Patrick McManus <mcmanus@ducksong.com>
To: Ian Hickson <ian@hixie.ch>
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Subject: Re: [hybi] Framing take IV [why fragment]
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On Wed, 2010-08-04 at 17:55 +0000, Ian Hickson wrote:
> On Wed, 4 Aug 2010, Patrick McManus wrote:
> > 
> > But I also believe fragments with fixed lengths are simpler than a BER 
> > because properly aligned lengths are always correct data - there are no 
> > error cases as all the bits are defined to be some quantity regardless 
> > of their arrangement. BER has error cases and determining the expressed 
> > quantity requires multiple indirections and a significant algorithm to 
> > use it.
> 


> As far as I can tell there are no error cases as defined in WebSockets.
> 

I believe the specific ber length suggestion was:

 - a BER-encoded packed integer, most-significant-digits first, high bit
used to indicate a continuation byte, giving the payload length.

In that case, as I understand it, it would be an error if the ber type
encoding byte didn't specify a universal primitive type of 2. (or maybe
I'm wrong and it needs to be some other identifier - but that doesn't
really matter).

it is not a big deal, but it is an error case.

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