🚀 go-pugleaf

In article <66926@cup.portal.com> Christopher_C_Lapp@cup.portal.com writes:

   How about a cryptosystem that used the teachings of various
   religious figures in the Bible as its key?As a spy, I would write a
   passionate letter detailing my sins and moral turpitude to my spy
   partner, and he/she would assign a "long beep" to the aspects of my
   sins that were in accordance with the bible, and a "short beep" to
   those that weren't.  T output would be a Morse-code of biblical
   proportions! By using the bible as t key, we could have
   uncrackable, undetectable, and public key encryption.  Any
   comments?  Chris Lapp

Not really uncrackable as the Bible is publicly available.
Read "The Key to Rebecca", by Ken Follett, for a good story
revolving around spies breaking a book code.

One advantage of the Bible is that, at least until recent times, carrying
one wouldn't draw suspicion to the spy.  (Carrying a Hagelin machine
would be pretty incriminating).  As a modern day alternative, I've
often thought the No Such Agency could do the following:

   - write encryption/decryption code that runs in an embedded
     micro of the kind found in calculators.

   - go to favorite defense contractor that also makes calculators
     (e.g. TI), and say "we want you to make a new model of simple,
     consumer calculator, priced so lots of people will buy them
     (here's some $$$ to make it profitable), and by the way, when
     the user types this undocumented 20-keystroke sequence, it should
     run this code that we'll supply (from previous step).

   - The calculator goes on the market and becomes popular, so
     the spy can carry one without drawing suspicion.  The special
     key sequence is made long enough and weird enough that no one
     will ever enter it by accident.  Of course, hitting clear
     in this mode reverts it to a normal calculator, in case 
     someone walks in on the spy (see Follett's "Eye of the Needle").