[CLUE-Tech] ssh or PGP encrypted wireless ethernet bridge?

[Jim Ockers]

Hi everyone,

I was wondering if anyone has built or knows of a wireless ethernet
bridge system that uses RSA keys or SSH or something to encrypt the
wireless traffic?

The application is two wired LANs that want to be connected over a
secure wireless link.  We would configure the wireless bridge radios
as a matched pair, so that they keys are unique to that pair of
wireless bridge hardware.

I'm sure that the Linux kernel bridging software would work fine over
wireless ethernet interfaces.

I'm also sure that the Linux kernel IPSec, or a ssh or vtun tunnel,
would work fine between links with IP addresses on each end.  I'm
envisioning that each end would have a private key, and the other
end's public key.  For performance reasons I think you would want 
to use a stream cipher like RC4 with the RSA encryption (block cipher)
just for exchanging the stream cipher keys.  IPSec does this
automatically.

I'm not sure how to make the bridging software work when the end
points don't have an IP address because it's a bridge.  Can you use
IPSec over a bridged link?

Anyone have any clues or pointers for me?  Also, is there a better
way to do this?  Naturally we don't trust WEP or even the newer
WEP stuff.  It seems that IPSec would be a good thing to use but 
we don't want to change the LAN-connected devices - we want the 
crypto stuff to be transparent to the things on each side of the 
bridge.

Thanks,
Jim

-- 
Jim Ockers, P.Eng. (ockers at ockers.net)
Contact info: please see http://www.ockers.net/