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Cc: freebsd-fs@freebsd.org
Subject: Re: Naive question about encrypted disks
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On Wed, 25 Oct 2006, Robert Watson wrote:

> Deriving the key when you have examples of plaintext and ciphertext for that 
> plaintext is known as a "known-plaintext attack".  Resistence to 
> known-plaintext attacks is one of the most important properties required of 
> modern crypto algorithms.  Other examples of cases where resistance to 
> known-plaintext attacks is critical include:

FYI, there are a number of quite good books on cryptography and the use of 
cryptography available.  Some of them even manage to get across the key 
concepts to be aware of as a consumer of cryptography without losing the 
reader in the details of how the algorithms are implemented. :-)

Ross Anderson's Security Engineering is now available online:

     http://www.cl.cam.ac.uk/~rja14/book.html

His crypto chapter (5) is both accessible and informative.

Robert N M Watson
Computer Laboratory
University of Cambridge