From: "Timothy C. May" <tcmay@got.net>
Date: Wed, 9 Oct 1996 10:03:57 -0700 (PDT)
To: cypherpunks@toad.com
Subject: "Forward Privacy" for ISPs and Customers
In-Reply-To: <199610082336.QAA24221@mail.pacifier.com>
Message-ID: <v03007802ae819385a300@[207.167.93.63]>
MIME-Version: 1.0
Content-Type: text/plain


IANAL, and I have been skimmming over most of the Bell v. Unicorn v. Nuri
debates about the legality of wiretapping, but something jumped out at me:

At 1:37 AM -0400 10/9/96, Black Unicorn wrote:

>include ISPs.  Constitutional arguments that ISPs are somehow different
>from phone companies and therefore not required to comply with wiretap
>orders?  Good luck.
>
>I know its fun to make the argument that ISPs and E-mail and NetPhone are
>all new technologies and so it must be unconstitutional to regulate them
>but the amusement in these cases stems from a wish that it was so, not
>fact or reason.

I agree that ISPs look a lot like phone companies for the purposes of
regulations and wiretaps. My ISP sells me some connectivity, sends me a
bill, etc.

Thus, if it is constitutionally OK (a technical term) for courts to order
phone logs to be turned over to law enforcement, why not logs of e-mail? Or
logs of Web sites visited, for example? I see no basis for a special
distinction. Records are records, and businesses routinely have to turn
over various records under court order.

However, there are certain things my phone company does *not* do. They
don't keep _copies_ (recordings) of my phone conversations. This means a
court order can't yield copies of past conversations. They also don't track
incoming phone calls to me. (I don't believe such records of incoming phone
calls are kept; maybe I'm wrong. Certainly with Caller ID, storing incoming
phone numbers is possible....I just don't think local or regional phone
companies care about such records, and hence don't bother to accumulate
them.)

Now, should the phone company keep such records, they would be accessible
via court order.

My point? ISPs are currently in a position to turn over *far* more
information than phone companies are able to turn over. It's as if the
phone companies kept audio recordings of all conversations, without even
the need for law enforcement to do a wiretap or pen register or whatnot. It
would be trivial for law enforcement to say: "Phone Company, here's a
subpoena/court order for the last 6 months of phone conversations Tim May
has had. Please ship the tapes via FedEx."

This makes the ISP case a bit different. Not legally, but technologically.

There are some fixes.

Something ISPs could do--and may do if there is sufficient customer
pressure--is to adopt a policy of "forward secrecy" (to slightly abuse this
technical term). That is, to have an explicit policy--implemented in the
software--of _really_ deleting the back messages once a customer downloads
them to his site. This means that _backups_ must be done in a careful
manner, such that even the backup tapes or disks are affected by a removal.

(Recall that Ollie North thought he had deleted his incriminating White
House PROFS messsages, but that they were faithfully preserved on backup
tapes, and could be retrieved.)

My Eudora Pro mail programs sucks down messages from my ISP and, as yours
probably does, tells the ISPs mail server to delete it upon downloading. An
option for users could be something like "Don't make longterm backups of my
account, and leave no copies whatsoever once I have downloaded my messages."

This would make the job of a law enforcement or TLA a lot more difficult
than it is now, where the e-mail and logs are ready to be handed over on a
silver platter, all nicely accumulated and human-readable.

Back to the legal issue. Perhaps the Digital Telephony Act will be
interpreted to require ISPs to make their systems "tappable," possibly by
adding message logging. possibly just by offering access to the T1s and T3s
only ("OK, Feds, here's where the T3 enters the building...be careful you
don't cut the core, OK?").

But if no logs and backup tapes of mail are kept, at least the job of
gaining access to communications is made more difficult.

And, I'm sure the lawyers will agree, while ISPs may be treated essentially
the same as telephone companies, absolutely *nothing* requires either to
keep specific kinds of account records (*), to "know their customer" (a la
banking laws, supposedly), or to record all traffic.

(* Prepaid phone cards, paid for in cash, and payphones, tell us that True
Names are not needed with the phone companies. And so on.)

We don't have to make it easy for them.

--Tim May


"The government announcement is disastrous," said Jim Bidzos,.."We warned IBM
that the National Security Agency would try to twist their technology."
[NYT, 1996-10-02]
We got computers, we're tapping phone lines, I know that that ain't allowed.
---------:---------:---------:---------:---------:---------:---------:----
Timothy C. May              | Crypto Anarchy: encryption, digital money,
tcmay@got.net  408-728-0152 | anonymous networks, digital pseudonyms, zero
W.A.S.T.E.: Corralitos, CA  | knowledge, reputations, information markets,
Higher Power: 2^1,257,787-1 | black markets, collapse of governments.
"National borders aren't even speed bumps on the information superhighway."