Cryptography
The Clinton administration,
civil libertarians, and the computer industry are enmeshed in a controversy
over cryptography policy. What is cryptography? How and why does the government
want to restrict it, and why are some people opposed?
Cryptography has two parts: encryption and decryption. Encryption
uses complicated mathematical formulas to make information indecipherable.
Decryption decodes the information. The strength of a computer
encryption algorithm depends largely on "key length," essentially the number of
possible combinations in the code. A key that is 40 bits long, for example, has
two raised to the 40 th power (2 40 ) possible combinations.
The longer the key, the harder the code is to crack.
Because of the rise of online commerce, there is a
burgeoning market for cryptography to protect electronic transactions and
sensitive data from hackers. But the government is concerned that foreign
powers (as well as terrorists and criminal cartels) might obtain cryptography
that is uncrackable. Advanced cryptography could be used to make phone
conversations impregnable to wiretap and financial records invulnerable to
subpoena. While the government permits U.S. companies to sell any cryptography
domestically, it has imposed export restrictions on technology stronger
than 40 bits.
These
restrictions have angered the computer industry. Because hackers have broken
40-bit technology, and because foreign companies already sell superstrong
encryption programs of 128 bits and more, there is little demand for legal
(40-bit and under) U.S. cryptography. The industry claims that export
restrictions could cost American computer companies more than $60 billion in
annual revenues by the year 2000: $6 billion from lost cryptography sales, the
rest from lost sales of associated hardware and software.
The Clinton administration's cryptography stand
reflects the strong law-and-order views of the FBI and Justice Department.
Critics argue that unbreakable encryption already is marketed by foreign
companies, so the export restrictions on American cryptography do no good.
Currently, there is no international encryption standard in place; but the
law-enforcement agencies hope that U.S. export policy will lead to one.
Since
1993, the administration has been using export restrictions as leverage to
encourage American companies to adopt a standard with a "backdoor "--a
route of entry for an outsider, such as the U.S. government, to recover
encrypted data. (The 128-bit encryption currently sold by foreign companies
contains no such backdoor.)
But the administration's efforts to establish a standard
have failed. First came the "Clipper Chip ," an 80-bit encryption
algorithm designed by the National Security Agency. In April 1993, the
administration said it would lift export restrictions on companies that use the
Clipper Chip. However, the government would keep a "key," which it could use to
tap a phone or decrypt data. Current rules requiring court orders for such
invasions of privacy would, presumably, continue to apply. Nevertheless, civil
libertarians denounced the Clipper Chip as a Big Brother intrusion, and the
computer industry refused to market encryption that the U.S. government could
crack at will.
In 1995,
the administration substituted "key escrow " for the Clipper Chip. Under
key escrow (dubbed "Clipper II" by opponents), companies could export strong
encryption algorithms, but would have to file a key with a government-approved
agent, such as a bank. But key escrow flopped, too. The computer industry said
it could not sell a program with a floating key accessible to the U.S.
government.
In a case of role reversal, the Democratic
administration's law-and-order stance has been matched by the Republicans'
rediscovery of civil liberties . Civil libertarians and the computer
industry recruited pro-business Republicans and anti-government conservatives
on Capitol Hill (as well as some liberal Democrats). In 1996, these legislators
introduced a bill to all but eliminate export restrictions. The legislation did
not go to a vote, but it has an excellent chance of passing next year. Bob Dole
endorsed the bill; Clinton has promised to veto it.
This political pressure
forced the Clinton administration to propose a compromise last week. Vice
President Gore offered an executive order that would ease export restrictions
by 1) raising the export limit from 40 bits to 56 bits for at least the next
two years (allowing U.S. companies to meet the current minimum commercial
standard); 2) transferring export-license authority from a State Department
military office, which almost always refuses applications, to the more friendly
Commerce Department; 3) permitting export of encryption of unlimited strength,
provided the technology incorporates "key recovery ." This is similar to
key escrow, except there is no single key and the government holds nothing. In
key recovery, a key is broken into several separate pieces of information and
the pieces are stored separately, perhaps by the users themselves, perhaps by
outside agents. Reconstructing the key requires the cooperation of each
holder.
If key recovery is adopted,
terrorists are likely to eschew it in favor of unbreakable technology. But if
banks, airlines, and communications companies accept key recovery, the
terrorists will risk potential exposure every time they do business with those
institutions. Key recovery has barely been tested, much less perfected. And
while a few companies--notably IBM--have embraced the technology, others--like
Netscape--strongly object to it. The rest of the industry is waiting to see how
much control the government demands over recovered keys. In fact, many experts
believe that the key recovery scheme is so vague and tentative as to be
irrelevant. They say the encryption issue will only be resolved when Congress
debates the issue next year.
