[47917] in Cypherpunks
Re: German home banking (fromn RISKS)
daemon@ATHENA.MIT.EDU (Andrew Loewenstern)
Wed Jan 24 20:39:25 1996
From: Andrew Loewenstern <andrew_loewenstern@il.us.swissbank.com>
Date: Wed, 24 Jan 96 19:34:20 -0600
To: David Mazieres <dm@amsterdam.lcs.mit.edu>
Cc: stevenw@best.com (Steven Weller), cypherpunks@toad.com
> Don't high speed modems transmit and receive on the same frequencies,
> using echo cancelation to decode the receive signals? Does that
> make it impossible to eavesdrop on high-speed (i.e. V32bis) modems?
No, and a lot of crackers and phone phreaks found out the hard way. You can
buy protocol analysers off-the-shelf that will give a dump of the entire
communication by just passively listening in (or possibly playing back a
recording). I have seen units that could decode all of the popular Blue Book
protocols for consumer equipment such as faxes and high-speed modems as well
as ISDN, T1, DS3, ATM, etc... Most are programmable and some are full-blown
computers running stripped down versions of Unix and can also be controlled
over the network from RealComputers. With multiple analysers and a little
custom software you could easily perform MITM attacks. The hardest part is
getting in the middle.
Modulation, comm-protocols, and compression techniques are not a replacement
for honest to goodness crypto.
andrew
