[hybi] Interface for Large Frames

"Bob Gezelter" <gezelter@rlgsc.com> Wed, 22 June 2011 21:58 UTC

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From: "Bob Gezelter" <gezelter@rlgsc.com>
To: hybi@ietf.org
Date: Wed, 22 Jun 2011 14:58:47 -0700
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Subject: [hybi] Interface for Large Frames
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The FILE methods in stdio.h include a "number of bytes" parameter. In
the context of the WebSocket protocol, the natural unit would appear to
be the frame. Once the frame has been retrieved by a user, then a
character-by-character state machine may (emphasis MAY) be appropriate,
however, the interface is best (most efficient) if entire frames can be
transferred at a time.

If programs must pull one character at a time, the efficiency will be
poor, with a large amount of overhead being consumed moving up and down
the call tree.

For an example of how a past message-based protocol deal with this
issue, Digital's NSP (see citation below) is an example. NSP handled
long messages by segmentation, passing the segments in order to user
program.

- Bob Gezelter, http://www.rlgsc.com

Digital Equipment Corporation (1984, July) “DECnet DIGITAL Network
Architecture NSP Functional Specification, Phase IV, Version 4.0.1”,
Retrieved from http://linux-decnet.sourceforge.net/docs/nsp401.txt on
March 23, 2011