Getting a user's specific key

From: Jacques Lebastard (jacques.lebastard_at_evidian.com)
Date: 04/26/04 

Date: Mon, 26 Apr 2004 17:18:34 +0200

I need to obtain a symmetric encryption key specific to a user. The key
needs to remain identical within the domain, whatever workstation the
user is logging-in from and whatever authentication method (password,
smart card) he uses.

I think a PKCS#5 derivation of the user's SID would provide sufficient
security strength but since the SID is a public data, I'm not sure...

Any better idea ?? 

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