From: Hal <74076.1041@CompuServe.COM>
Date: Mon, 22 Feb 93 10:53:54 PST
To: Cypherpunks <cypherpunks@toad.com>
Subject: Government encryption
Message-ID: <930222183917_74076.1041_DHJ70-1@CompuServe.COM>
MIME-Version: 1.0
Content-Type: text/plain


Loyd Blankenship asks whether PEM involves having a government agency create
key pairs.
 
I think this may be confusing two different issues.  PEM does not involve
having anyone else create key pairs for you.  You create your own keys and
keep the private key secret just as in any other public key system.
However, PEM requires you to get a "certificate" from an agency in order to
use the system.
 
The certificate-issuing agency is typically expected to be your employer or
your university, from my reading of the RFC's.  Large institutions like
these would issue certificates, which are basically similar to PGP's key
signatures, which certify that you are who you say you are.  The large
institutions themselves would have their own public keys signed by an agency
higher in some key-signing hierarchy.  Last I checked, the top of the
hierarchy was the company RSADSI; they would certify the companies and the
companies would certify the employees.  I think this part may have changed
a little in the last few drafts of the new RFC.
 
So, there's not really any government involvement.  There is a centralized
hierarchy for key signatures, but key generation is still an individual
activity.  Oh, yes, there may also be a charge for getting your key signed;
this charge might be borne by the company/university in some cases.  There
is also a provision to get a certificate outside this system; these
"persona" certificates wouldn't really vouch for anything but they would let
you use PEM.  I'm not sure what they will cost.
 
The other idea which Loyd might have been mixing up with this was Dorothy
Denning's proposal several months ago that all users of public key systems
be required to register their secret keys with some quasi-governmental
agency.  (Originally she proposed the Justice Department, then later
suggested an independent group.)  This way if the government wanted to spy
on your communications, it would have to get a court order (as it does now,
in theory, for wiretaps), and take this court order to the key-holding
agency to get them to reveal your secret keys.  Then it could read your
messages.
 
This proposal was subjected to a very strong attack led largely by our own
Tim May.  It soon became known as the "lead balloon" for its lack of support
and has not been heard of recently.  I don't think anyone would be terribly
surprised if some variant were to resurface, though.
 
Hal Finney