Re: RC4 for Authentication and Encryption

From: Unruh (unruh-spam_at_physics.ubc.ca)
Date: 04/28/05 

Date: 27 Apr 2005 23:31:50 GMT

"Joseph Ashwood" <ashwood@msn.com> writes:

>Your analogy is exactly the reason RC4 should not be trusted. We have a wide
>selection of chisels that work extremely well against RC4. These range from
>straight out attacks like are applicable to WEP all the way to a
>distinguisher from random, none of these are in any way new. RC4 has been
>fatally wounded for about a decade, it should be allowed to die.

Those are against bad implimentations of RC4. They would be true of any
stream cypher, never mind RC4.
While RC4 may be distinguishabel from random after TB, I do not believe
that anyone has shown even the ghost of an idea of how to use this to
attack a cypher stream encoded by RC4.

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