Areo: ~rabsef's big break - Pontifex on

The Solitaire or Pontifex algorithm is a cryptographic algorithm designed by cryptographer Bruce Schneier based on coordinating two decks of cards so that they can be used to communicate between two field agents. Given a standard deck of 52 playing cards and two distinguishable jokers, a message may be encrypted as a keystream, or sequence of values combined with the message to encrypt or decrypt it. The algorithm features prominently in Neal Stephenson's novel Cryptonomicon [...]

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