From: Scott Brickner <sjb@universe.digex.net>
Date: Mon, 23 Oct 95 17:08:45 PDT
To: tcmay@got.net (Timothy C. May)
Subject: Re: Don't Kill the Messenger--A New Slant on Remailers
In-Reply-To: <acac7cd8430210046e54@[205.199.118.202]>
Message-ID: <199510240008.UAA11781@universe.digex.net>
MIME-Version: 1.0
Content-Type: text/plain


Timothy C. May writes:
>THE ROLE OF THE "MESSENGER"
>
>But I think I have a longer term solution, one that involves a change in
>thinking about the differences between the _originator_ of a message and
>the mere _messenger_.
>
>The notion is to much more explicitly separate the functions of the
>"messenger" or "deliverer" from the "originator" or "sender." Granted, this
>is already done in the sense that a piece of e-mail goes through many
>hands. For example, Hal's message that I am responding to here has this in
>the header blocks, showing some of the "couriers" or "messengers":

This is an interesting notion, but one I don't think is quite right.
The anonymous remailer is not merely a courier.  It actively modifies
the message envelope by removing any indication of its origin.  The
main issue in Hal's quoted complaints are that the receiver isn't able
to contact the sender.  This fact is a direct result of the action of
the remailer.

Consider what would happen if a remailer were set up that *didn't*
remove the "From:" data.  Anonymizing remailer operators could attempt
to limit complaints by forwarding everything through the non-anonymizer
to make it the last link.  Who do you think would get the complaints?
The last anonymizer.

>A MAIL DELIVERY SERVICE (don't we already have them? yes, but....)
>
>So, how would this work?
>
>With remailers, even more steps need to be taken to make it absolutely
>clear that the delivered message is not _from_ the last Internet site that
>shows up in the "From:" field. More than just disclaimers are needed.
>
>One approach is for a _notification-based_ system. To wit:
>
>"You have a piece of mail awaiting at our mail delivery service. The
>originator is unknown. The title of the message is "Tentacles of Medusa
>Must Die!" You may retrieve this message by replying to this notification
>with the word "Yes" anywhere in the Subject field. This message will be
>kept for 60 days and then deleted."

I had a similar idea that I mentioned to Hal in a private message.  How
about a POP server that authenticates with crypto, and accepts and
holds email addressed to the keyid of a PGP key?  You send email to
4466A801@keymail.com it holds them for 30 days (or whatever) and
discards them.  When I connect to the server to retrieve my mail, it
asks for my public key, encrypts a random challenge with it, and I tell
it the decrypted version.  Having proved that I can read messages
encrypted to the key, it delivers messages addressed to the hash of the
key.  It might also allow me to configure an address where
notifications of new messages should be sent.

It's an interesting twist on the anon.penet.fi system, since you
needn't bother tracking all the nym/email mappings, and *can't* give
CoS any incriminating information.