From: Hal <hfinney@shell.portal.com>
Date: Tue, 21 May 1996 15:04:37 +0800
To: cypherpunks@toad.com
Subject: An alternative to remailer shutdowns
Message-ID: <199605202202.PAA27515@jobe.shell.portal.com>
MIME-Version: 1.0
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Several remailers have shut down recently.  This may be in part a
byproduct of the ongoing struggle between dissidents and adherents of
the Church of Scientology.  Also, levels of abuse seem to be increasing
in general as more people come on the net and learn to use the
remailers.  Since by their very nature remailers prevent
accountability, there is nothing to stop one or more persons from
sending illegal material which will cause the remailers to be
threatened by legal actions.

I was contacted by the FBI on Friday due to some threatening mail which
was apparently sent through my remailer.  According to 18 USC 875(c),
"Whoever transmits in interstate commerce any communication containing
any threat to kidnap any person or any threat to injure the person of
another, shall be fined not more than $1,000 or imprisoned not more
than five years, or both."  I may not be able to continue operating
either of my remailers (alumni.caltech.edu and shell.portal.com) for
much longer due to this kind of abuse.

Shutting down remailers not only reduces the number available for general
use, it also causes problems for people who are using the remailers to
manage pseudonyms.  If their reply chains used a remailer which shuts
down they have to reconstruct the chains, which is at least a nuisance.
There was also a posting recently to comp.org.eff.talk by Jonathon Cline,
jcline@trumpet.aix.calpoly.edu, about efforts to set up fully anonymous
nym based mailing lists.  He mentioned that the decrease in the number of
remailers is causing problems with their plans.

An alternative I am considering would reduce the utility of the remailer
while still allowing these "consensual" uses to continue.  Presently the
remailers deal with abuse via "block lists", sets of addresses that mail
can't be sent to.  Generally these are created when someone complains
about some mail they have received.  By setting up blocking, at least
they will not get harrassing anonymous mail once they have complained.
But in some cases, as in the case that is causing me headaches now, even
one message is too much.

My thought is to turn the block list concept on its head, and make it a
"permit list".  Simply, the remailer will only send mail to people who
have voluntarily indicated their willingness to receive it.  Someone who
has not sent in a message granting this permission will not be sent
mail.  For larger forums such as newsgroups and mailing lists, permission
may be granted by some consensus mechanism.  Most would be blocked, but a
few like alt.anonymous.messages and the cypherpunks list would be
permitted, and others could be added if they wished.

This should hopefully essentially eliminate complaints about abuse,
much more effectively than the current method of block lists.  People
who want to test the remailer by sending mail to themselves, as most
people do when they are learning, can simply register themselves on the
permit list.  People who want to receive anonymous mail, or participate
in anonymous mailing lists, can register themselves.  People who want
to use nyms can register themselves.  People who run other remailers
can register.  It's all voluntary, and if someone does get some
objectionable message at least they will know that they granted
permission.  They can always ask to be taken off the list.

Feedback welcome -

Hal Finney

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