[tcpm] Comment on draft-gont-tcpm-tcp-timestamps-00

Eric Rescorla <ekr@networkresonance.com> Sat, 15 November 2008 23:51 UTC

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Date: Sat, 15 Nov 2008 17:38:19 -0600
From: Eric Rescorla <ekr@networkresonance.com>
To: tcpm@ietf.org, draft-gont-tcpm-tcp-timestamps@tools.ietf.org
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Subject: [tcpm] Comment on draft-gont-tcpm-tcp-timestamps-00
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In Section 2, you write:

   the requirements of Section 4.2.2 of RFC 1323 [RFC1323], and F() is a
   function that should not be computable from the outside.  Therefore,
   we suggest F() to be a cryptographic hash function of the
   connection-id and some secret data.

Sorry to sound like nitpicky cryptographer guy here, but you want 
a PRF, not a hash function. A hash function might or might not 
be good enough depending on the function... 


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