From owner-freebsd-security  Thu Mar 14  3:23:31 2002
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From: "John R. Shannon" <john@johnrshannon.com>
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To: "jack xiao" <jack_xiao99@hotmail.com>,
	<freebsd-security@FreeBSD.ORG>
Subject: Re: AES
Date: Thu, 14 Mar 2002 04:23:11 -0700
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AES and DES are compared on this AES fact sheet:

http://csrc.nist.gov/encryption/aes/aesfact.html

The problem with DES is that it's 56 bit key, which was adequate in the 70s, 
can be discovered by exhaustive keysearch. 

3DES attacks this by applying DES 3 times: encrypt with 1 key, decrypt with a 
second, and encrypt with a third. The best known attack on 3DES is O(2^108) 
operations with something like 2^64 storage. The problem with 3DES, is it's 
high computational cost.

On Wednesday 13 March 2002 08:54 pm, jack xiao wrote:
> Hi,
>
> Can anybody show me some resource about the comparison between AES and 3DES
> or DES?
>
> Thanks a lot!
>
> Jack
>

-- 

John R. Shannon
john@johnrshannon.com

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