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From: (Noel Chiappa)
Subject: [TUHS] Re: CRC calculation in the 1980s
Date: Tue, 19 Sep 2023 07:42:29 -0400 (EDT)	[thread overview]
Message-ID: <> (raw)

    > From: Paul Ruizendaal

    > Any suggestions as to why the on-the-fly algorithm did not catch on
    > more in the 1980's? Maybe it was simply less well known than I think?

I can't answer that directly, but I will point you at IEN-56, "CRC Checksum
Calculation", by Dave Reed (11-Sep-78):

Dave wanted the INWG to use a more powerful (in terms of detecting errors)
CRC, instead of the simple summation eventually adopted, in TCP and IP. So he
produced code to implement a particular CRC, to show people that it would not
be particularly expensive (whether in time, or space, I don't alas recall
definitively; speed would have been an important consideration, when
competing with the summation, though).

This would have been close to the leading edge of our knowledge at the time;
Dave liked playing around with math, and at about that time he did a very
fast DES implementation.


             reply	other threads:[~2023-09-19 11:42 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2023-09-19 11:42 Noel Chiappa [this message]
2023-09-19 12:54 ` Lars Brinkhoff
2023-09-19 16:00 ` Paul Ruizendaal
  -- strict thread matches above, loose matches on Subject: below --
2023-09-18 23:02 [TUHS] " Paul Ruizendaal
2023-09-18 23:34 ` [TUHS] " Robert Brockway
2023-09-19  0:02 ` segaloco via TUHS
2023-09-19 15:34 ` Paul Winalski
2023-09-19 15:50   ` Dan Cross
2023-09-19 16:22     ` Paul Winalski

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