From: Matthew J Ghio <mg5n+@andrew.cmu.edu>
Date: Tue, 12 Oct 93 17:49:55 PDT
To: cypherpunks@toad.com
Subject: Re: Spread-spectrum net (vulnerability of)
In-Reply-To: <9310090132.AA08927@dink.foretune.co.jp>
Message-ID: <Ugip0Ky00awQIzQl9m@andrew.cmu.edu>
MIME-Version: 1.0
Content-Type: text/plain


>>Anyone who wants to take you down will only need (1) a detector that can
>>point out your boxes and (2) a small caliber rifle.
>
>Errrrr. Hadn't thought of that. Placement will be a major factor, I
>beleieve.
>
>>Since the cost to find and destroy is much less than the cost to make and
>>deploy, a covert network of this sort wouldn't last long.  An _overt_
>>network, perhaps a commercial entity that networks an entire city, would
>>be an interesting prospect.
>
>Depends how you place them. If you put them _on top_ of things, you'd need 
>a helicopter to shoot 'em.

Someone walking around a city shooting a rifle is likely to attract a
lot more attention than a secret network would.  Secondly, the
transmitter doesn't necessarily have to be exposed, it could be kept
hidden and only the antenna would need to be exposed.  You'd have to be
a damn good shot to hit a wire antenna.  Plus the antenna would be easy
to disguise or hide in many places.

>>The techniques for maintaining location information on actual machines
>>connected to the net, and for updating them as they move, are actually
>>quite simple and well understood (cellular telephones are a simple,
>>dumb version of the technology).  The trick is to find out a way that
>>the network can know where you are but not give that information out
>>(even to the owners of the network), without unacceptable overheads.
>
>This is true.
>But if we make the things in thick boxes (well, slightly bullet-proof,
>anyway), and put them in places where theyare hard to shoot at, then we 
>should be right. We would only need a few each suburb.

Well, you may know that you can reach a certain person thru site #127,
and that stie #127 can be reached thru site 35 or site 68, and so
on...which gives you a sort of virtual-space map, which would reveal
nothing about actual phyical location of the sites or the person you are
contacting.  Suppose you were connected to site #1 and you were
communicating with site #3 thru site #2.  Site #3 could be 50 meters
away, or 2 km, and you would never know the difference because you
didn't have any way to directly contact site #3.  Hence we have achieved
our objective - you know how to contact site #3 in netspace - it has a
cybernetic location relative to other sites, but that tells you nothing
about it's actual physical location.