Papers and notes

• Pseudo-random number generators:
  • “Practical random number generation” - an article on very simple yet effective QRN PRNG, suitable for most practical applications
  • Yasmarang - a pseudorandom number generator
  • Sapparot - a pseudorandom number generator
  • “Sapparot-2. Fast Pseudo-Random Number Generator” (pdf, 115k) and two attacks against it: first by Greg Rose and second by Francois Grieu.
• Zcipher Algorithm - a toy block cipher for fun and experiments
• “On Single Cycle Functions” (pdf, 97k) - a note about few invertible single cycle funcions. See also: “T-functions Testbed”
• “How to prevent biometrics from being lousy” - a note on how to convert biometrics to be an effective two-factors authentication on its own
• “Using hard mathematical problems to prevent spam” - a note about simple spam prevention idea

Codebreaking and puzzle solutions (used to be spoilers):
»  Solution to the GCHQ Challenge
»  GCHQ Commemoration Week Challenge Solution
»  Depuzzle DSD