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RE: passwords
From: "Robinson, Sonja" <SRobinson () HIPUSA com>
Date: Wed, 19 Feb 2003 09:28:29 -0500

That's it???   Arguments can be made for changing passwords from between 30
and 90 days.  Each argument has valid points which I will not elaborate on
again since it's been beaten to death.  30 to 90 is fine but you need to
make sure there is complexity involved.  The harder the complexity the more
valid the argument for 90 days so users won't be tempted to write it down.
I wouldn't exceed more than 90 ever but I prefer 30.  A combination of
Capital and lowercase letters, Numbers and Symbols.  Require 3 out of the 4
minimum.  Make a minimum length of 7.  If you are using LANMan make it  7
not 8 since 7 is harder to crack for LANMan other reasons that I also won't
go into.  You should have a password history as well.  I prefer 12 so that
people can slightly change the password to be Passw0rd1, Passw0rd2, ....
Run enforcement onthese policies and run password checkers to verify.  

IMHO, 30 days is best.  I've had 30 days with these rules and users are
fine.  At first people tend to kick and scream but if you reduce the times
in increments of say 15 days every 3 months people don't notice the

Good Password - N0t*N0w, Abs0lutely%, 
Bad Password - tuxedo, names, birthdates, License plates, names, pets,
anything in a dictionary (incl foreign languages, klingon, etc.), anything
identifiable or guessable about a person, phone #'s, etc.

-----Original Message-----
From: ullmic6 [mailto:ullmic6 () web de] 
Sent: Monday, February 17, 2003 2:02 PM
To: security-basics () securityfocus com
Subject: passwords

Hello all,

one of the favorite subjects in my company seems to be the 
strength of passwords. We force our users to change their 
mail password every 90 days. Does this make sense? Why?


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