Archive-name: cryptography-faq/part09
Last-modified: 94/06/07

This is the ninth of ten parts of the sci.crypt FAQ. The parts are
mostly independent, but you should read the first part before the rest.
We don't have the time to send out missing parts by mail, so don't ask.
Notes such as ``[KAH67]'' refer to the reference list in the last part.

The sections of this FAQ are available via anonymous FTP to rtfm.mit.edu 
as /pub/usenet/news.answers/cryptography-faq/part[xx]. The Cryptography 
FAQ is posted to the newsgroups sci.crypt, talk.politics.crypto, 
sci.answers, and news.answers every 21 days.


Contents:

9.1. What is the National Security Agency (NSA)?
9.2. What are the US export regulations?
9.3. What is TEMPEST?
9.4. What are the Beale Ciphers, and are they a hoax?
9.5. What is the American Cryptogram Association, and how do I get in touch?
9.6. Is RSA patented?
9.7. What about the Voynich manuscript?


9.1. What is the National Security Agency (NSA)?

  The NSA is the official communications security body of the U.S.
  government. It was given its charter by President Truman in the early
  50's, and has continued research in cryptology till the present. The 
  NSA is known to be the largest employer of mathematicians in the world,
  and is also the largest purchaser of computer hardware in the
  world. Governments in general have always been prime employers of
  cryptologists. The NSA probably possesses cryptographic expertise many
  years ahead of the public state of the art, and can undoubtedly break
  many of the systems used in practice; but for reasons of national
  security almost all information about the NSA is classified.

  Bamford's book [BAMFD] gives a history of the people and operations of
  the NSA. The following quote from Massey [MAS88] highlights the
  difference between public and private research in cryptography:

  ``... if one regards cryptology as the prerogative of government,
  one accepts that most cryptologic research will be conducted
  behind closed doors. Without doubt, the number of workers engaged
  today in such secret research in cryptology far exceeds that of
  those engaged in open research in cryptology. For only about 10
  years has there in fact been widespread open research in
  cryptology. There have been, and will continue to be, conflicts
  between these two research communities. Open research is common
  quest for knowledge that depends for its vitality on the open
  exchange of ideas via conference presentations and publications in
  scholarly journals. But can a government agency, charged with
  responsibilities of breaking the ciphers of other nations,
  countenance the publication of a cipher that it cannot break? Can
  a researcher in good conscience publish such a cipher that might
  undermine the effectiveness of his own government's code-breakers?
  One might argue that publication of a provably-secure cipher would
  force all governments to behave like Stimson's `gentlemen', but one
  must be aware that open research in cryptography is fraught with
  political and ethical considerations of a severity than in most
  scientific fields. The wonder is not that some conflicts have
  occurred between government agencies and open researchers in
  cryptology, but rather that these conflicts (at least those of which
  we are aware) have been so few and so mild.''

9.2. What are the US export regulations?

  In a nutshell, there are two government agencies which control
  export of encryption software. One is the Bureau of Export
  Administration (BXA) in the Department of Commerce, authorized by
  the Export Administration Regulations (EAR). Another is the Office
  of Defense Trade Controls (DTC) in the State Department, authorized
  by the International Traffic in Arms Regulations (ITAR). As a rule
  of thumb, BXA (which works with COCOM) has less stringent
  requirements, but DTC (which takes orders from NSA) wants to see
  everything first and can refuse to transfer jurisdiction to BXA.

  The newsgroup misc.legal.computing carries many interesting
  discussions on the laws surrounding cryptographic export, what
  people think about those laws, and many other complex issues which
  go beyond the scope of technical groups like sci.crypt. Make sure to
  consult your lawyer before doing anything which will get you thrown in
  jail; if you are lucky, your lawyer might know a lawyer who has at
  least heard of the ITAR.

9.3. What is TEMPEST?

  TEMPEST is a standard for electromagnetic shielding for computer
  equipment. It was created in response to the discovery that
  information can be read from computer radiation (e.g., from a CRT) at
  quite a distance and with little effort.

  Needless to say, encryption doesn't do much good if the cleartext
  is available this way.

9.4. What are the Beale Ciphers, and are they a hoax?

  (Thanks to Jim Gillogly for this information and John King for
  corrections.)

  The story in a pamphlet by J. B. Ward (1885) goes: Thomas
  Jefferson Beale and a party of adventurers accumulated a huge mass
  of treasure and buried it in Bedford County, Virginia, leaving
  three ciphers with an innkeeper; the ciphers describe the
  location, contents, and intended beneficiaries of the treasure.
  Ward gives a decryption of the second cipher (contents) called B2;
  it was encrypted as a book cipher using the initial letters of the
  Declaration of Independence (DOI) as key. B1 and B3 are unsolved;
  many documents have been tried as the key to B1.

  Aficionados can join a group that attempts to solve B1 by various
  means with an eye toward splitting the treasure:

  The Beale Cypher Association
  P.O. Box 975
  Beaver Falls, PA 15010

  You can get the ciphers from the rec.puzzles FAQL by including the
  line:

  send index

  in a message to netlib@peregrine.com and following the directions.
  (There are apparently several different versions of the cipher
  floating around. The correct version is based on the 1885 pamphlet,
  says John King <kingj@hpcc01.corp.hp.com>.)

  Some believe the story is a hoax. Kruh [KRU88] gives a long list of
  problems with the story. Gillogly [GIL80] decrypted B1 with the DOI
  and found some unexpected strings, including ABFDEFGHIIJKLMMNOHPP.
  Hammer (president of the Beale Cypher Association) agrees that this
  string couldn't appear by chance, but feels there must be an
  explanation; Gwyn (sci.crypt expert) is unimpressed with this
  string.

9.5. What is the American Cryptogram Association, and how do I get in touch?

  The ACA is an organization devoted to cryptography, with an emphasis
  on cryptanalysis of systems that can be attacked either with
  pencil-and-paper or computers. Its organ ``The Cryptogram'' includes
  articles and challenge ciphers. Among the more than 50 cipher types in
  English and other languages are simple substitution, Playfair,
  Vigenere, bifid, Bazeries, grille, homophonic, and cryptarithm.

  Dues are $20 per year (6 issues) for new members, $15 thereafter; more
  outside North America; less for students under 18 and seniors.  Send
  checks to ACA Treasurer, P.O. Box 198, Vernon Hills, IL 60061-0198.

9.6. Is RSA patented?

  Yes. The patent number is 4,405,829, filed 12/14/77, granted 9/20/83.
  For further discussion of this patent, whether it should have been
  granted, algorithm patents in general, and related legal and moral
  issues, see comp.patents and misc.legal.computing. For information
  about the League for Programming Freedom see [FTPPF]. Note that one of
  the original purposes of comp.patents was to collect questions such as
  ``should RSA be patented?'', which often flooded sci.crypt and other
  technical newsgroups, into a more appropriate forum.

9.7. What about the Voynich manuscript?

  The Voynich manuscript is an elaborately lettered and illustrated
  document, in a script never deciphered. It has been handed down for
  centuries by a line of art collectors and has uncertain origination.
  Much speculation and attention has been focused on its potential
  meaning.

  nelson@reed.edu (Nelson Minar) says there is a mailing list on the
  subject. The address to write to subscribe to the VMS mailing list
  is: <voynich-request@rand.org>

  the ftp archive is: rand.org:/pub/voynich

  There's all sorts of information about the manuscript itself, of
  course. A good bibliography can be found on the ftp site. [KAH67]
  gives a good introduction.