Wep 40bit key (Shared key?)

[Kim Hawtin]

On Sun, Feb 16, 2003 at 05:55:16AM +0000, Brad Brad wrote:
> >On Sat, 15 Feb 2003, Brad Brad wrote:
> >> Hi, i've got my rebadged orinoco gold working fine unWEPed, however
> >> enabling WEP kills things.  I read that i can only have 40bit,
> >> aparently its key length is 5 chars though? my AP won't accept less
> >> than 10chars and calls that 64bit.  from my understanding 64bit is
> >> 40bit + marketing?  any deas on whats happening there?  128 is also
> >> 13 char verse 26 char btw.
> >
> >`iwconfig eth0 key s:abcde` is equivalent to `iwconfig eth0 key
> >6162-6364-65` with or without the hyphens.  Microsoft Windows XP will
> >take either 5 ASCII bytes or 10 hex digits without hyphens.  Your
> >access point probably wants you to translate your ASCII string into
> >hex.  Or generate a "truly" random hex string and use that both
> >places.  `ipsec ranbits 40` is convenient if you have it installed.
> >Omit the underbars that come out every 8 bytes.
> >
> >You're right that 64 bits = 40 bits + marketing.  The firmware
> >supplements the user-provided key with the card-dependent part of the
> >MAC address, to guarantee that each card on the net uses a different
> >WEP key (if the cards are from the same manufacturer).  Similarly
> >with 104 + 24 = 128 bits, which doubles the time it takes AirSnort to
> >crack the key.
> >
> >Here's my user support writeup about setting up wireless cards, with
> >some notes at the end about setting up your own network.
> >http://www.math.ucla.edu/computing/user_support/hardware/wiresetup.html
>
>
> Hi, thanks, but i tried this, and WEP still wouldn't work.  I booted
> back to windows which i knew worked, and it only worked when i checked
> "Shared Key". I read in some possibly old mailing lists that Shared
> Key wasn't enabled in some drivers.  I couldn't find any information
> on the orinoco_cs driver, however i couldn't grep anything interesting
> from the source.  Anyone else know any more?

two things to remember;
- not all wep implementations are compatible
- use alpha numeric characters as some implemtnations encode other
  characters differently, like $%^&*() etc...
 
then remember that using WEP is a pain on the arse to debug and 
adds quite a bit of overhead to the wireless card, so retransmissions are
required! i spent a week debugging an acces point connection only to
find that the processor usage was 100% at 5Mbit/s.

so i gave up on WEP for a joke and use SSL wraped service, SSH and
if you need to use dozer boxes then maybe IPSec/FreeSwan is the go ...

cheers,

Kim