Re: The TCP and UDP checksum algorithm may soon need updating

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 05 June 2020 17:00 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Stewart Bryant <stewart.bryant@gmail.com>, Craig Partridge <craig@tereschau.net>, ietf@ietf.org
Subject: Re: The TCP and UDP checksum algorithm may soon need updating
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Date: Fri, 05 Jun 2020 12:59:56 -0400
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Stewart Bryant <stewart.bryant@gmail.com> wrote:
    > Would the Fletcher checksum, which is also 16 bits but has CRC like
    > properties and is easy for low powered h/w to calculate be sufficient?

    > I am curious as to where these errors are occurring. The MAC will be
    > CRC protected in post case. Are the errors surviving the MAC or are
    > they introduced in the h/w?

I think that we must assume some amount of bit flips in memory between MACs
(meaning both MAC CRC and MAC devices).   I wonder if this has also gotten
worse now that ethernet controllers can calculate (and segment) traffic.

/me pines for ubiquitous deployment of AH.

--
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-