Re: Length vs Complexity

[Walter Goulet <wgoulet () gmail com>]

I would agree with your argument; longer passwords will create a
larger keyspace more rapidly than a shorter password with more
complexity rules.

The way I think about it is like this:

A 8 character password that is restricted to the 52 upper/lowercase
letters plus valid digits 0-9 is going to have a total of 62 possible
values for each position, for a total of 62^8 possible passwords (218
trillion or so). If you increase the length to just 12 characters, you
get like 62^12 or approx. 3 trillion possible password values.

If you instead permit users to say use all printable ASCII characters
(128 possible values for each position), you are just changing the
base value (128^8 or 72 quintillion or so).

So, by requiring longer passphrases you are exponentially increasing
the size of the keyspace.

On Thu, Sep 16, 2010 at 12:01 PM, Mike Razzell <m.razzell () gmail com> wrote:
> Users hear constantly that they should add complexity to their
> passwords, but from the math of it doesn't length beat complexity
> (assuming they don't just choose a long word)?  This is not to suggest
> they should not use special characters, but simply that something like
> Security.Basics.List would provide better security than D*3ft!7z.  Is
> that correct?
>
> Thanks,
> -Mike
>
> --
> Sent from my mobile device
>
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------------------------------------------------------------------------
Securing Apache Web Server with thawte Digital Certificate
In this guide we examine the importance of Apache-SSL and who needs an SSL certificate.  We look at how SSL works, how 
it benefits your company and how your customers can tell if a site is secure. You will find out how to test, purchase, 
install and use a thawte Digital Certificate on your Apache web server. Throughout, best practices for set-up are 
highlighted to help you ensure efficient ongoing management of your encryption keys and digital certificates.

http://www.dinclinx.com/Redirect.aspx?36;4175;25;1371;0;5;946;e13b6be442f727d1
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