[118615] in Cypherpunks
Re: Unplugged! The biggest hack in history
daemon@ATHENA.MIT.EDU (Bill Stewart)
Mon Oct 4 04:25:34 1999
Message-Id: <3.0.5.32.19991004000837.007ae310@idiom.com>
Date: Mon, 04 Oct 1999 00:08:37 -0700
To: cypherpunks@cyberpass.net
From: Bill Stewart <bill.stewart@pobox.com>
In-Reply-To: <4.2.0.58.19991003231344.00bc0940@mail.wenet.net>
Mime-Version: 1.0
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Reply-To: Bill Stewart <bill.stewart@pobox.com>
At 11:23 PM 10/03/1999 -0700, Greg Broiles wrote:
>Yes, this process would be easier if the phone company can provide access
>to one side or the other of the conversation. It's still not a walk in the
>park, nor is it as easy as hooking up an extra eavesdropping modem at each
>end, because as Vin noted, the modems participate actively in
>negotiating/shaping the stream of data, and the modem on your end isn't
>necessarily going to follow the hops that the first two modems made.
It's not just that the eavesdropper has a hard time figuring out
what Alice and Bob's modems negotiated - it's that the negotiation
determines the correct voltage/power/etc levels for each frequency
to cram the most possible bits through the connection between
those two endpoints given their actual analog characteristics,
and Eve's modem is on a different hunk of wire so it needs
different levels to optimally transmit data to it.
(I'm going on hearsay here - this isn't my field,
though I studied some topics near it 20+ years ago :-)
But apparently it's been hard to eavesdrop on modems
since about 9600 baud days.
Greg wrote about audio recordings of 300 baud working fine.
In fact that's what some of the early low-cost PCs used for data storage -
I think the Coleco Adam did, and one or more of the C-64, TRS-80, etc.
There's also a CD by "Information Society" with a track called "300 8N1"
or something about like that - play it to a 300-baud modem set appropriately
and it'll give you text.
Thanks!
Bill
Bill Stewart, bill.stewart@pobox.com
PGP Fingerprint D454 E202 CBC8 40BF 3C85 B884 0ABE 4639
