From: fiedorow@function.mps.ohio-state.edu (Zbigniew Fiedorowicz)
Newsgroups: sci.crypt
Subject: Re: Key registration proposal in CACM
Date: 19 Nov 1992 14:58:29 -0500
Organization: Department of Mathematics, The Ohio State University
Distribution: world
NNTP-Posting-Host: function.mps.ohio-state.edu


In a previous article in this newsgroup, Howard Gayle writes
>The November 1992 issue of Communications of the ACM has a
>letter (pp. 19-20) by Brad Knowles of the Defense Information 
>Systems Agency, calling for key registration.

Here is the letter in question:

-------------------------------------------------------------------------------
After reading all the National Security Agency bashing in the July issue of
Communications, I was both amazed and appalled that one very important topic
was omitted.  Namely, that the NSA, through its actions to squelch the
publication of good encryption algorithms and attempts to force standardization
on poor ones, has defeated its very purpose, in addition to causing very grave
harm to national security.

Firstly, the former Soviet Union (now the Commonwealth of Independent States) 
has had good cheap working copies of both DES and RSA for years now according
to [1].  Secondly, anyone who wants either the algorithms themselves or the
executable code, can easily get what they want.  In fact, I have found the
source code to DES available via anonymous ftp on the Internet.  The RSA
algorithm is somewhat more difficult to acquire, but not much.  Clearly the NSA
has failed miserably in keeping these algorithms from circulating outside
certain circles within the U.S.

Many people already know that government agencies are required by law, to
adhere to the various different standards enacted by NIST through their Federal
Information Processing Standards (FIPS).  What they may not realize is that, by
congressional order, the federal agencies are required to use Commercial Off-
The-Shelf (COTS) Software, wherever feasible.  If American companies refrain
from producing a quality encryption product due to the FIPS or influences by
the NSA, and the federal agencies desire to use a quality product, then they
must go to contractors to have one specially written at a good deal of cost. 
We end up spending significantly more simply because the products we need are
not commercially available.

Additionally, since American companies are not given a good standardization
method method of efficiently and appropriately protecting their confidential
data, they are very prone to industrial espionage.  Most of the countries which
have been our national security espionage adversaries in the past have since
turned a significant portion of their efforts over to industrial espionage,
making them very vulnerable.  Since national security depends, in large part,
upon the welfare of defense industry and other high-technology companies, NSA
has succeeded in doing very grave harm to national security interests by
leaving these companies to the wolves.  Of course, these companies can also
contract to have good encryption algorithms implemented for them, but then that
puts them in the same boat as the federal government, in that they would be
spending much more money than necessary.

Then we have the issue of interoperability -- if we are using known commercial
implementations of some standard encryption algorithm, then we could be
reasonably sure that we could communicate with each other with a minimum of
additional difficulty.  However, if we have our own private versions of even
good encryption algorithms, no matter how well-written the standard, then there
are very serious questions about compatibility, which means, more likely than
not, encrypting something would most likely not be done, which would mean it is
effectively totally unprotected.  If only the FIPS standard encryption
algorithm were a good one to begin with, and a good implementation of it
(through the proper choice of long keys, etc., ..., as suggested by Rivest et
al. [4]) were included as part of this standard, then these additional and
totally unnecessary costs could be avoided.

In order to balance the needs of the users and the government's needs, I
suggest the following:


Have a central Key Distribution Facility (KDF) that is run under the auspices
of the IEEE, ANSI, FBI, NIST, another government agency, or some neutral third
party -- one that gives a reasonable guarantee (one which I will not attempt to
define here) that the keys will be kept safely from prying eyes, even those
that belong to the government.  Specify that the RSA encryption algorithm (or
some other public-key encryption algorithm) will be used to safely encrypt
messages, and that all keys for this implementation will be issued by this KDF.
Furthermore, if law enforcement agencies can present a legitimate wiretap order
to this KDF, then issue them the private key(s) for the person(s) or
organizations that is/are going to be wiretapped.

There are many implementation details that have been omitted from this
discussion, but I feel that this will allow the public the same reasonable
guarantee today, namely that no one is illegally listening to conversations.
If an international implementation of the encryption scheme is desired, then
the organization could be sponsored under the CCITT, ISO, UN, or some other
appropriate international organization.

Brad Knowles,
Defense Information Systems Agency
BLKNOWLE@JDSSC.DCA.MIL
Newsgroups: sci.crypt