Decrypting the Puzzle Palace 

previously published in the July, 1992 issue of 
Communications of the ACM

by
John Perry Barlow


"A little sunlight is the best disinfectant."
				--Justice Louis Brandeis
	
	
Over a year ago, in a condition of giddier innocence than I enjoy today,
I wrote the following about the discovery of Cyberspace: Imagine
discovering a continent so vast that it may have no other side. Imagine
a new world with more resources than all our future greed might exhaust,
more opportunities than there will ever be entrepreneurs enough to
exploit, and a peculiar kind of real estate which expands with
development.

One less felicitous feature of this terrain which I hadn't noticed at
the time was a long-encamped and immense army of occupation.

This army represents interests which are difficult to define. It guards
the area against unidentified enemies. It meticulously observes almost
every activity undertaken there, and continuously prevents most who
inhabit its domain from drawing any blinds against such observation.

This army marshals at least 40,000 troops, owns the most advanced
computing resources in the world, and uses funds the dispersal of which
does not fall under any democratic review.

Imagining this force won't require the inventive powers of a William
Gibson. The American Occupation Army of Cyberspace exists. Its name is
the National Security Agency.

It can be argued that this peculiar institution inhibits free trade, has
damaged American competitiveness, and poses a threat to liberty anywhere
people communicate with electrons. Its principal function, as my
colleague John Gilmore puts it, is "wire-tapping the world." It is free
to do this without a warrant from any judge.

It is legally constrained from domestic surveillance, but precious few
people are in a good position to watch what, how, or whom the NSA
watches. Those who are tend to be temperamentally sympathetic to its
objectives and methods. They like power, and power understands the
importance of keeping it own secrets and learning everyone else's.

Whether it is meticulously ignoring every American byte or not, the NSA
is certainly pursuing policies which will render our domestic affairs
transparent to anyone who can afford big digital hardware.  Such
policies could have profound consequences on our liberty and privacy.

More to point, the role of the NSA in the area of domestic privacy needs
to be assessed in the light of other recent federal initiatives which
seem aimed at permanently denying privacy to the inhabitants of
Cyberspace, whether foreign or American.

Finally it seems an opportune time, directly following our disorienting
victory in the Cold War, to ask if the threats from which the NSA
purportedly protects Americans from are as significant as the hazards
the NSA's activities present.

Like most Americans I'd never given much thought to the NSA until
recently. (Indeed its very existence was a secret for much of my life.
Beltway types used to joke that NSA stood for "No Such Agency.") I
vaguely knew that the NSA was one of the twelve or so shadowy federal
spook houses erected shortly after the creation of the Iron Curtain with
the purpose of stopping its advance.

The NSA originated in response to a memorandum sent by Harry Truman on
October 24, 1952 to Secretary of State Dean Acheson and Defense
Secretary Robert Lovatt. This memo, the very existence of which remained
secret for almost 40 years, created the NSA, placed it under the
authority of the Secretary of Defense, and charged it with monitoring
and decoding any signal transmission relevant to the security of the
United States.

Even after I started noticing the NSA, my natural immunity to paranoia
combined with a belief in the incompetence of all bureaucracies
continued to mute any sense of alarm. This was before I began to
understand the subterranean battles raging over data encryption and the
NSA's role in them. Lately, I'm less sanguine.

Encryption may be the only reliable method for securing privacy in the
inherently public domain of Cyberspace. I certainly trust it more than
privacy protection laws. Relying on government to protect your privacy
is like asking a peeping tom to install your window blinds.

In fact, we already have a strong-sounding federal law protecting our
electronic privacy, the Electronic Communications Privacy Act or ECPA.
But this law is not very effective in those areas where electronic eaves
dropping is technically easy. This is especially true in the area of
cellular phone conversations, which, under the current analog
transmission standard, are easily accessible to anyone from the FBI to
you.

The degree of present-day law enforcement apprehension over secure
cellular encryption provides evidence of how seriously they've been
taking ECPA. Law enforcement organizations are moving on a variety of
fronts to see that robust electronic privacy protection systems don't
become generally available to the public.  Indeed, the current
administration may be so determined to achieve this end they may be
willing to paralyze progress in America's most promising technologies
rather than yield.

Push is coming to shove in two areas of communications technology:
digital transmission of heretofore analog signals, and the encryption of
transmitted data.

As the communications service providers move to packet switching, fiber
optic transmission lines, digital wireless, ISDN and other advanced
techniques, what have been discrete channels of continuous electrical
impulses, voices audible to anyone with alligator clips on the right
wires, are now becoming chaotic blasts of data packets, readily
intelligible only to the sender and receiver. This development
effectively forecloses traditional wire-tapping techniques, even as it
provides new and different opportunities for electronic surveillance.

It is in the latter area where the NSA knows its stuff. A fair
percentage of the digital signals dispatched on planet Earth must pass
at some point through the NSA's big sieve in Fort Meade, Maryland, 12
underground acres of the heaviest hardware in the computing world.
There, unless these packets are also encrypted with a particularly
knotty algorithm, sorting them back into their original continuity is
not very difficult.

In 1991, alarmed at a future in which it would have to sort through an
endless fruit salad of encrypted bits, the FBI persuaded Senator Joseph
Biden to include certain language in Senate Bill 266. The new language
in the bill required electronic communications services and those who
created communications devices to implement only such encryption methods
as would assure government's ability to extract the plain text of any
voice or data communications in which it took a legal interest. It was
as if the government had responded to a technological leap in lock
design by requiring all building contractors to supply it with skeleton
keys to every door in America.

The provision raised wide-spread concern in the computer community,
which was better equipped to understand its implications than the
general public. In August of last year, the Electronic Frontier
Foundation, in cooperation with Computer Professionals for Social
Responsibility and other industry groups, successfully lobbied to have
it removed from the bill.

Our celebration was restrained. We knew we hadn't seen the last of it.
For one thing, the movement to digital communications does create some
serious obstacles to traditional wire-tapping procedures. I fully
expected that law enforcement would be back with new proposals, which I
hoped might be ones we could support. But what I didn't understand then,
and am only now beginning to appreciate, was the extent to which this
issue had already been engaged by the NSA in the obscure area of export
controls over data encryption algorithms.  Encryption algorithms,
despite their purely defensive characteristics, have been regarded by
the government of this country as weapons of war for many years. If they
are to be employed for privacy (as opposed to authentication) and they
are any good at all, their export is licensed under State Department's
International Traffic in Arms Regulations or ITAR.

The encryption watchdog is the NSA. It has been enforcing a policy,
neither debated nor even admitted to, which holds that if a device or
program contains an encryption scheme which the NSA canUt break fairly
easily, it will not be licensed for international sale.  Aside for
marveling at the silliness of trying to embargo algorithms, a practice
about as pragmatic as restricting the export of wind, I didn't pay much
attention to the implications of NSA encryption policies until February
of this year. It was then that I learned about the deliberations of an
obscure group of cellular industry representatives called the Ad Hoc
Authentication Task Force, TR45.3 and of the influence which the NSA has
apparently exercised over their findings.

In the stately fashion characteristic of standard-setting bodies, this
group has been working for several years on a standard for digital
cellular transmission, authentication, and privacy protection. This
standard is known by the characteristically whimsical telco moniker
IS-54B.

In February they met near Giants Stadium in East Rutherford, NJ. At that
meeting, they recommended, and agreed not to publish, an encryption
scheme for American-made digital cellular systems which many
sophisticated observers believe to be intentionally vulnerable.  It was
further thought by many observers that this Rdumbing downS had been done
indirect cooperation with the NSA.  Given the secret nature of the new
algorithm, its actual merits were difficult to assess. But many
cryptologists believe there is enough in the published portions of the
standard to confirm that it isnUt any good.

One cryptographic expert, who asked not to be identified lest the NSA
take reprisals against his company, said:
"The voice privacy scheme, as opposed to the authentication scheme, is
pitifully easy to break. It involves the generation of two `voice
privacy masks' each 260 bits long. They are generated as a byproduct of
the authentication algorithm and remain fixed for the duration of a
call. The voice privacy masks are exclusive_ORed with each frame of data
from the vocoder at the transmitter. The receiver XORs the same mask
with the incoming data frame to recover the original plain text. Anyone
familiar with the fundamentals of cryptanalysis can easily see how weak
this scheme is."

And indeed, Whitfield Diffie, co-inventor of Public Key cryptography and
arguably the dean of this obscure field, told me this about the fixed
masks:
"Given that description of the encryption process, there is no need for
the opponents to know how the masks were generated. Routine
cryptanalytic operations will quickly determine the masks and remove
them."

Some on the committee claimed that possible NSA refusal of export
licensing had no bearing on the algorithm they chose. But their decision
not to publish the entire method and expose it to cryptanalytical abuse
(not to mention ANSI certification) was accompanied by the following
convoluted justification:
"It is the belief of the majority of the Ad Hoc Group, based on our
current understanding of the export requirements, that a published
algorithm would facilitate the cracking of the algorithm to the extent
that its fundamental purpose is defeated or compromised." (Emphasis
added.)

Now this is a weird paragraph any way you parse it, but its most
singular quality is the sudden, incongruous appearance of export
requirements in a paragraph otherwise devoted to algorithmic integrity.
In fact, this paragraph is itself code, the plain text of which goes
something like this: "We're adopting this algorithm because, if we
don't, the NSA will slam an export embargo on all domestically
manufactured digital cellular phones."

Obviously, the cellular phone system manufacturers and providers are not
going to produce one model for overseas sale and another for domestic
production. Thus, a primary effect of NSA-driven efforts to deny some
unnamed foreign enemy secure cellular communications is on domestic
security. The wireless channels available to Americans will be cloaked
in a mathematical veil so thin that, as one crypto- expert put it, "Any
county sheriff with the right PC-based black box will be able to monitor
your cellular conversations."

When I heard him say that, it suddenly became clear to me that, whether
consciously undertaken with that goal or not, the most important result
of the NSA's encryption embargoes has been the future convenience of
domestic law enforcement. Thanks to NSA export policies, they will be
assured that, as more Americans protect their privacy with encryption,
it will be of a sort easily penetrated by authority.

I find it increasingly hard to imagine this is not their real objective
as well. Surely, the NSA must be aware of how ineffectual their efforts
have been in keeping good encryption out of inimical military
possession. An algorithm is somewhat less easily stopped at the border
than, say, a nuclear reactor. As William Neukom, head of Microsoft Legal
puts it, "The notion that you can control this technology is comical."

I became further persuaded that this was the case upon hearing, from a
couple of sources, that the Russians have been using the possibly
uncrackable (and American) RSA algorithm in their missile launch codes
for the last ten years and that, for as little as five bucks, one can
get a software package called Crypto II on the streets of Saint
Petersburg which includes both RSA and DES encryption systems.

Nevertheless, the NSA has been willing to cost American business a lot
of revenue rather than allow domestic products with strong encryption
into the global market.

While it's impossible to set a credible figure on what that loss might
add up to, it's high. Jim Bidzos, whose RSA Data Security licenses RSA,
points to one major Swiss bid in which a hundred million dollar contract
for financial computer terminals went to a European vendor after
American companies were prohibited by the NSA from exporting a truly
secure network.

The list of export software containing intentionally broken encryption
is also long. Lotus Notes ships in two versions. DonUt count on much
protection from the encryption in the export version. Both Microsoft and
Novell have been thwarted in their efforts to include RSA in their
international networking software, despite frequent publication of the
entire RSA algorithm in technical journals all over the world.

With hardware, the job has been easier. NSA levied against the inclusion
of a DES chip in the AS/390 series IBM mainframes in late 1990 despite
the fact that, by this time, DES was in widespread use around the world,
including semi-official adoption by our official enemy, the USSR.

I now realize that the Soviets have not been the NSA's main concern at
any time lately. Naively hoping that, with the collapse of the Evil
Empire, the NSA might be out of work, I learned that, given their own
vigorous crypto systems and their long use of some embargoed products,
the Russians could not have been the threat from whom this forbidden
knowledge was to be kept. Who has the enemy been then? I started to ask
around.

Cited again and again as the real object of the embargoes were Third-
World countries, terrorists and... criminals. Criminals, most generally
drug-flavored, kept coming up, and nobody seemed concerned that some of
their operations might be located in areas supposedly off- limits to NSA
scrutiny.

Presumably the NSA is restricted from conducting American surveillance
by both the Foreign Intelligence Surveillance Act of 1978(FISA) and a
series of presidential directives, beginning with one issued by
President Ford following Richard Nixon's bold misuse of the NSA, in
which he explicitly directed the NSA to conduct widespread domestic
surveillance of political dissidents and drug users.

But whether or not FISA has actually limited the NSA's abilities to
conduct domestic surveillance seemed less relevant the more I thought
about it. A better question to ask was, "Who is best served by the NSA's
encryption export policies?" The answer is clear: domestic law
enforcement. Was this the result of some plot between NSA and, say, the
Department of Justice? Not necessarily.

Certainly in the case of the digital cellular standard, cultural
congruity between foreign intelligence, domestic law enforcement, and
what somebody referred to as "spook wannabes on the TR45.3 committee"
might have a lot more to do with the its eventual flavor than any actual
whisperings along the Potomac.

Unable to get anyone presently employed by the NSA to comment on this or
any other matter, I approached a couple of old hands for a highly
distilled sample of intelligence culture.

I called Admirals Stansfield Turner and Bobby Ray Inman. Their Carter
administration positions as, respectively, CIA and NSA Directors, had
endowed them with considerable experience in such matters In addition,
both are generally regarded to be somewhat more sensitive to the limits
of democratic power than their successors. And their successors seemed
unlikely to return my calls.  My phone conversations with Turner and
Inman were amiable enough, but they didn't ease my gathering sense that
the NSA takes an active interest in areas beyond its authorized field of
scrutiny.  Turner started out by saying he was in no position to confirm
or deny any suspicions about direct NSA-FBI cooperation on encryption.
Still, he didn't think I was being irrational in raising the question.
In fact, he genially encouraged me to investigate the matter further.
He also said that while a sub rosa arrangement between the NSA and the
Department of Justice to compromise domestic encryption would be
"injudicious," he could think of no law, including FISA (which he helped
design), which would prevent it.

Alarmingly, this gentleman who has written eloquently on the hazards of
surveillance in a democracy did not seem terribly concerned that our
digital shelters are being rendered permanently translucent by and to
the government. He said, "A threat could develop...terrorism, narcotics,
whatever...where the public would be pleased that all electronic traffic
was open to decryption. You can't legislate something which forecloses
the possibility of meeting that kind of emergency."

Admiral Inman had even more enthusiasm for assertive governmental
supervision. Although he admitted no real knowledge of the events behind
the new cellular encryption standard, he wasn't disturbed to hear it
might be purposely flawed.

And, despite the fact that his responsibilities as NSA Director had been
restricted to foreign intelligence, he seemed a lot more comfortable
talking about threats on the home front.  "The Department of Justice,"
Inman began, "has a very legitimate worry. The major weapon against
white collar crime has been the court-ordered wiretap. If the criminal
elements go to using a high quality cipher, the principal defense
against narcotics traffic is gone."  This didn't sound like a guy who,
were he still head of NSA, would rebuff FBI attempts to get a little
help from his agency.

He brushed off my concerns about the weakness of the cellular encryption
standard. "If all you're seeking is personal privacy, you can get that
with a very minimal amount of encipherment."  Well, I wondered, Privacy
from whom?

Inman seemed to regard real, virile encryption to be something rather
like a Saturday Night Special. "My answer," he said, "would be
legislation which would make it a criminal offense to use encrypted
communication to conceal criminal activity."

Wouldn't that render all encrypted traffic automatically suspect? I
asked.

"Well," he said, "you could have a registry of institutions which can
legally use ciphers. If you get somebody using one who isn't registered,
then you go after him."

You can have my encryption algorithm, I thought to myself, when you pry
my cold dead fingers from its private key.

It wasn't a big sample, but it was enough to gain an appreciation of the
cultural climate of the intelligence community. And these guys are the
liberals. What legal efficiencies might their Republican successors be
willing to employ to protect the American Way?  Without the familiar
presence of the Soviets, we can expect a sharp increase in over-rated
bogeymen and virtual states of emergency.  This is already well under
way. I think we can expect our drifting and confused hardliners to burn
the Reichstag repeatedly until they have managed to extract from our
induced alarm the sort of government which makes them feel safe.

This process has been under way for some time. One sees it in the war on
terrorism, against which pursuit "no liberty is absolute," as Admiral
Turner put it. This, despite the fact that, during last year for which I
have a solid figure, 1987, only 7 Americans succumbed to terrorism.

You can also see it clearly under way in the War on Some Drugs. The
Fourth Amendment to the Constitution has largely disappeared in this
civil war. And among the people I spoke with, it seemed a common canon
that drugs (by which one does not mean Jim Beam, Marlboros, Folger's, or
Halcion) were a sufficient evil to merit the government's holding any
keys it wanted.

One individual close to the committee said that at least some of the
aforementioned "spook wannabes" on the committee were interested in weak
cellular encryption because they considered warrants not "practical"
when it came to pursuing drug dealers and other criminals using cellular
phones.

In a fearful America, where the people cry for shorter chains and
smaller cages, such privileges as secure personal communications are
increasingly regarded as expendable luxuries. As Whitfield Diffie put
it, "From the consistent way in which Americans seem to put security
ahead of freedom, I fear that most would prefer that all electronic
traffic was open to government decryption."

In any event, while I found no proof of an NSA-FBI conspiracy to gut the
American cellular phone encryption standard, it seemed clear to me that
none was needed. The same results can be delivered by a cultural
"auto-conspiracy" between like-minded hardliners and cellular companies
who will care about privacy only when their customers do.

You don't have to be a hand-wringing libertarian like me to worry about
the domestic consequences of the NSA's encryption embargoes.  They are
also, as stated previously, bad for business. Unless, of course, the
business of America is no longer business but, as sometimes seems the
case these days, crime control.

As Ron Rivest (the "R" in RSA) said to me, "We have the largest
information-based economy in the world. We have lots of reasons for
wanting to protect information, and weakening our encryption systems for
the convenience of law enforcement doesn't serve the national interest."

But by early March, it was clear that this "business-oriented"
administration had made a clear choice to favor cops over commerce even
if the costs to the American economy were to become extremely high.

A sense of White House seriousness in this regard could be taken from
their response to the first serious effort by Congress to bring the NSA
to task for its encryption embargoes. Rep. Mel Levine (D- Calif.)
proposed an amendment to the Export Administration Act to transfer mass
market software controls to the Commerce Department, which would relax
the rules. The administration responded by saying that they would veto
the entire bill if the Levine amendment remained attached to it.

Even though it appeared the NSA had little to fear from Congress, the
Levine amendment may have been part of what placed the agency in a
bargaining mood for the first time. They entered into discussions with
the Software Publishers Association who, acting primarily on behalf of
Microsoft and Lotus, got to them to agree "in principle" to a
streamlined process for export licensing of encryption which might
provide for more robust standards than previously allowed.

But the negotiations between the NSA and the SPA were being conducted
behind closed doors. The NSA imposed an understanding that any agreement
would be set forth only in a "confidential" letter to Congress. As in
the case of the digital cellular standard, this would eliminate the
public scrutiny by cryptography researchers.

Furthermore, some cryptographers worried that the encryption key lengths
to which the SPA appeared willing to restrict its members might be too
short for the sorts of brute-force decryption assaults which advances in
processor technology will yield in the near future.  And brute force
decryption has always been the NSA's strong suit.  The impression
engendered by the style of the NSA-SPA negotiations did not inspire
confidence. The lack of confidence will operate to the continued
advantage of foreign manufacturers in an era when more and more
institutions are going to be concerned about the privacy of their
digital communications.

But the economic damage which the NSA-SPA agreement might cause would be
minor compared to what would result from a startling new federal
initiative, the Department of Justice's proposed legislation on digital
telephony. If you're wondering what happened to the snooping provisions
which were in Senate Bill 266, look no further.  They're back. Bigger
and bolder than before.

They are contained in a sweeping proposal by the Justice Department to
the Senate Commerce Committee.  It proposes legislation which would
"require providers of electronic communications services and private
branch exchanges to ensure that the Government's ability to lawfully
intercept communications is unimpeded by the introduction of advanced
digital telecommunications technology or any other telecommunications
technology."

This really means what it says: before any advance in telecommunications
technology can be deployed, the service providers and manufacturers must
assure the cops that they can tap into it. In other words, development
in digital communications technology must come to a screeching halt
until The Department of Justice can be assured that it will be able to
grab and examine data packets with the same facility they have long
enjoyed with analog wire-tapping.

It gets worse. The initiative also provides that, if requested by the
Attorney General, "any Commission proceeding concerning regulations,
standards or registrations issued or to be issued under authority of
this section shall be closed to the public." This essentially places the
Attorney General in a position to shut down any telecommunications
advance without benefit of public hearing.

When I first heard of the digital telephony proposal, I assumed it was a
kind of bargaining chip. I couldn't imagine it was serious. But it now
appears they are going to the mattresses on this one.

Taken together with NSA's continued assertion of its authority over
encryption, a pattern becomes clear. The government of the United States
is so determined to maintain law enforcement's traditional wire-tapping
abilities in the digital age that it is willing to cripple the American
economy. This may sound hyperbolic, but I believe it is not.

The greatest technological advantages this country presently enjoys are
in the areas of software and telecommunications. Furthermore, thanks in
large part to the Internet, much of America is already wired for bytes.
This is as significant an economic edge in the Information Age as the
existence of a railroad system was for England one hundred fifty years
ago.

If we continue to permit the NSA to cripple our software and further
convey to the Department of Justice the right to stop development the
Net without public input, we are sacrificing both our economic future
and our liberties. And all in the name of combating terrorism and drugs.

This has now gone far enough. I have always been inclined to view the
American government as fairly benign as such creatures go. I am
generally the least paranoid person I know, but there is something scary
about a government which cares more about putting its nose in your
business than it does about keeping that business healthy.  As I write
this, a new ad hoc working group on digital privacy, coordinated by the
Electronic Frontier Foundation, is scrambling to meet the challenge. The
group includes representatives from organizations like AT&T, the
Regional Bells, IBM, Microsoft, the Electronic Mail Association and
about thirty other companies and public interest groups.

Under the direction of Jerry Berman, EFF's Washington office director,
and John Podesta, a capable lobbyist and privacy specialist who helped
draft the ECPA, this group intends to stop the provisions in digital
telephony proposal from entering the statute books.

We intend to work with federal law enforcement officials to address
their legitimate concerns. We donUt dispute their need to conduct some
electronic surveillance, but we believe this can be assured by more
restrained methods than they're proposing. We are also preparing a
thorough examination of the NSA's encryption export policies and looking
into the constitutional implications of those policies. Rather than
negotiating behind closed doors, as the SPA has been attempting to do,
America's digital industries have a strong self-interest in banding
together to bring the NSA's procedures and objectives into the sunlight
of public discussion.

Finally, we are hoping to open a dialog with the NSA. We need to develop
a better understanding of their perception of the world and its threats.
Who are they guarding us against and how does encryption fit into that
endeavor? Despite our opposition to their policies on encryption export,
we assume that NSA operations have some merit. But we would like to be
able to rationally balance the merits against the costs.

The legal right to express oneself is meaningless if there is no secure
medium through which that expression may travel. By the same token, the
right to hold unpopular opinions is forfeit unless one can discuss those
opinions with others of like mind without the government listening in.

Even if you trust the current American government, as I am still
inclined to, there is a kind of corrupting power in the ability to
create public policy in secret while assuring that the public will have
little secrecy of its own.

In its secrecy and technological might, the NSA already occupies a very
powerful position. And conveying to the Department of Justice what
amounts to licensing authority for all communications technology would
give it a control of information distribution rarely asserted over
English-speaking people since Oliver Cromwell's Star Chamber
Proceedings.

Are there threats, foreign or domestic, which are sufficiently grave to
merit the conveyance of such vast legal and technological might?  And
even if the NSA and FBI may be trusted with such power today, will they
always be trustworthy? Will we be able to do anything about it if they
aren't?

Senator Frank Church said of NSA technology in 1975 words which are more
urgent today:
"That capability at any time could be turned around on the American
people and no American would have any privacy left. There would be no
place to hide. If this government ever became a tyranny, the
technological capacity that the intelligence community has given the
government could enable it to impose total tyranny. There would be no
way to fight back, because the most careful effort to combine together
in resistance to the government, no matter how privately it was done, is
within the reach of the government to know. Such is the capacity of this
technology."

San Francisco, California
Monday, May 4, 1992