Re: Wireless security

From: Volker Birk (
Date: 10/30/05

Date: 30 Oct 2005 14:49:39 +0200

John Hyde <> wrote:
> So, in a brute force attack, how long does it take to try each possible
> permutation?

This depends on the entropy your passphrase has. So better use enough

> Of course, if the attacker does not know that they are attacking a
> Diceware passphrase, then they'll have to try all the alphanumeric
> combinations of the same length (Diceware words are 5 letters, right?)

Wrong. A dictionary attack any sensible attacker will do first, because
it's likely that words are used, and it can be done without extra costs
before a brute force attack.

> But perhaps "brute force" means something else.

No, your description is correct.

> Well, that was one of my questions, "is the MAC encrypted by WEP?" I
> guess this would be a "NO."

Yes, it will be a "No" ;-)

> Still, I would not say MAC filtering is
> totally useless. At least it forces an attacker to wait around until I
> connect to see what an acceptable MAC address is. Not much of a burden,
> but it prevents a "drive by."

There are only 2^48 possible MAC addresses. And many of them are reserved.
And the manufacturers have fixed address ranges for their NICs.


"Ich bin ein freier Mensch und werde jetzt von meinen Freiheitsrechten
Gebrauch machen - und zwar ausgiebig - natürlich nur in dem Rahmen, den
Otto Schily mir noch zur Verfügung stellt."
                   Wolfgang Clement am 10.10.05 als Noch-Superminister