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Re: [hybi] frame length encoding

"Shelby Moore" <shelby@coolpage.com> Fri, 20 August 2010 19:20 UTC

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Date: Fri, 20 Aug 2010 15:20:44 -0400
From: Shelby Moore <shelby@coolpage.com>
To: John Tamplin <jat@google.com>
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Cc: Hybi <hybi@ietf.org>
Subject: Re: [hybi] frame length encoding
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> Option 2
> ========
> Use 7 bits in the frame header, and if the value is 0-125, that is the
> length.  If the value is 126, then the next 2 bytes are a 16-bit length.
> If
> the value is 127, the next 8 bytes are a 63-bit length (the high bit must
> be
> zero).
>
> long long len = readByte();
> switch (len) {
>   case 126:
>     len = readUnsignedShort();
>     break;
>   case 127:
>     len = readLongLong();
>     break;
> }

+1

Much superior than Option 1.

Reason is because with Option 1 overhead for small packets 127+ in size,
is significant (6% not including the rest of header).  And this Option 2,
only slightly increases the overhead for only one size value, 126.

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