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Re: Senior M$ member says stop using passwords completely!
From: "Pavel Kankovsky" <peak () argo troja mff cuni cz>
Date: Sun, 17 Oct 2004 21:21:07 +0200 (CEST)

On Sat, 16 Oct 2004, Frank Knobbe wrote:

It's a nice recommendation of MS to make (to use long passphrases
instead of passwords). But I don't consider 14 chars a "passphrase".
Perhaps they should enable more/all password components to handle much
longer passwords/phrases.

A passphrase consisting of 7 words and 12 bits of entropy per a word is
as guessable as a password with 14 characters and 6 bits of entropy per 
a character. You get 84 bits of total entropy in both cases.

The only advantage of passphrases is that lusers might find long random
sequences of words easier to remember than long random sequences of

(But wait: 12 bits of entropy per a word--this is equivalent to a uniform
choice of one word out of 4096. 4 thousand? That might exceed an average
luser's vocabulary by an order of magnitude! ;>)

--Pavel Kankovsky aka Peak  [ Boycott Microsoft--http://www.vcnet.com/bms ]
"Resistance is futile. Open your source code and prepare for assimilation."

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