[14689] in Cypherpunks

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Re: Faster way to deescrow Clipper won't work

daemon@ATHENA.MIT.EDU (Sidney Markowitz)
Fri Jun 3 12:35:26 1994

Date: Fri, 3 Jun 1994 09:29:56 -0700
To: cypherpunks@toad.com
From: sidney@taurus.apple.com (Sidney Markowitz)

Perry answered most of my questions with the new information that the
checksum is a function of the IV and session key. That still leaves one big
one unanswered: Doesn't the Clipper chip at the other end of the message
have to compute and send a LEAF too? Otherwise there would be no way for
the wiretappers to identify it. And that LEAF will contain the proper
session key unless both ends are using the same hack.

Also, what does Clipperphone have that the Tessera board doesn't which
keeps this hack from working? Is enough known about the workings of the two
so that someone could build a computer-based telephone using Tessera that
would be compatible with Clipperphone yet use this hack?

 -- sidney <sidney@taurus.apple.com>




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