From: yanek@novavax.nova.edu (Yanek Martinson)
Date: Thu, 17 Dec 92 13:53:18 PST
To: cypherpunks@toad.com
Subject: 1st dc-net works!
Message-ID: <9212172152.AA20073@novavax.nova.edu>
MIME-Version: 1.0
Content-Type: text/plain


Finally, I got a dc-net working.  It is now quite primitive, and useful
only as a proof of concept.  It does not yet do any key management, I
just copied the binaries of several unix utilities to be used as one
time pads.  The reservation system does not work yet.  If there is a 
message to be sent, it is sent immediately.  That means only one
of the participants can send a message in one round.  The messages
are not forwarded anywhere, they are just dropped to "outgoing" 
directory.  

It runs on one machine, under three accounts I created just for that 
purpose.  The mail keeps going back and forth constantly between the
three accounts, with null files being deposited to the outgoing
directories.  

Temporary files are being created and deleted.

As soon as I put a file in one of the incoming directories, within one
round it appears in each of the outgoing directories.

So the main function works.

It is written in perl, because of the ease I can manipulate binary data
of any size.

As soon as I add the minimal necessary features (PGP based key exchange,
and reservation blocks) I will be looking for some people to participate
in an experimental dc-net.  People who want to participate in this, should
have fast, reliable, e-mail connections (preferably round-trip time
to any other participant should be less than 10 minutes).  If even one
participant has a slow link, it will hold everyone up.  You also need
the ability to pipe incoming mail with a certain subject header through
an arbitrary program.  You can use any of the various 'slocal' programs,
or you could use elm's filter program, or any other means.  You also need
to have perl working on your system.  You need PGP.  

As someone suggested, an arbitrary group of people might not have much
to talk about amongst themselves, so the next feature will be forwarding
to a mailing address (or list), a newsgroup, or another dc-net.  It is
very simple to do the forwarding, it is a little more complicated,
and interesting, to decide who will do the forwarding.  I would not
want to rely on any single site serving as a gateway, since that
would introduce a single point of compromise.  I would rather have
some dynamic system, similar to the reservation blocks, that would
let the net randomly decide who will forward a particular message.

As soon as this first test network has run for a couple of days, and all
the bugs are fixed, I will release the code, so that anybody can work
on it.  I expect that some people will work on various projects I mentioned
in the "FUTURE ENCHANCEMENTS" section of my initial posting on this
topic.  I hope that people who add features to the system send the mods
back to me, so I can incorporate them in a new version.

When there is a number of networks running, it will be interesting to
experiment with hierarchical nets, or linked networks of networks.  


--
Yanek Martinson    mthvax.cs.miami.edu!safe0!yanek     uunet!medexam!yanek
this address preferred -->> yanek@novavax.nova.edu <<-- this address preferred
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