From: ichudov@algebra.com (Igor Chudov @ home)
Date: Sat, 29 Jun 1996 15:02:07 +0800
To: JMKELSEY@delphi.com
Subject: Re: anonymous mailing lists
In-Reply-To: <01I6GF62YWG291VYF3@delphi.com>
Message-ID: <199606290404.XAA32220@manifold.algebra.com>
MIME-Version: 1.0
Content-Type: text


How about this attack: suppose I want to find out who hides behind
an alias MightyPig@alpha.c2.org and I have the ability to monitor
all internet traffic. Then I simply start mailbombing that address
and see whose account gets unusually high traffic volume.

A nice, albeit quite expensive, way of pretection from traffic analysis
is to create a mailing list (or a newsgroup) and forward all messages to
all users of that mailing list or newsgroup. Of course, since messages
are encrypted, only the recipients will be able to decrypt them.

This way the list of suspects is all subscribers of that list or
newsgroup and there is no way to discriminate them.

Instead of having messages to be sent to all recipients all the time,
alpha.c2.org may be programmed so that it sends out every message not to
only one recipient X, but to X and 20 other randomly selected people.

It apparently makes traffic analysis much harder.

Then users of alpha.c2.org will have to install mail filters that
automatically delete all incoming mail not intended to be read by them
(they can't read such messages anyway).

	- Igor.