3 ms·

Cool! In a similar vein, I've wondered if it's possible to design a reasonably secure zero knowledge proof or challenge/response scheme that's simple enough to

Cool! In a similar vein, I've wondered if it's possible to design a reasonably secure zero knowledge proof or challenge/response scheme that's simple enough to be performed using only mental math and maybe some simple physical tools like playing cards or dice (ideally no pen and paper). This way you could prove that you know some secret without it ever even leaving your brain. If it can be done without any external tools at all, then you could even use it in public settings without any fear of your secret leaking.

mangodrunk 3y ago
Checkout Solitaire by Bruce Schneier [1]. > In Neal Stephenson’s novel Cryptonomicon, the character Enoch Root describes a cryptosystem code-named “Pontifex” to another character named Randy Waterhouse, and later reveals that the steps of the algorithm are intended to be carried out using a deck of playing cards. These two characters go on to exchange several encrypted messages using this system. The system is called “Solitaire” (in the novel, “Pontifex” is a code name intended to temporarily conceal the fact that it employs a deck of cards) and I designed it to allow field agents to communicate securely without having to rely on electronics or having to carry incriminating tools. An agent might be in a situation where he just does not have access to a computer, or may be prosecuted if he has tools for secret communication. But a deck of cards…what harm is that? > Solitaire gets its security from the inherent randomness in a shuffled deck of cards. By manipulating this deck, a communicant can create a string of “random” letters that he then combines with his message. Of course Solitaire can be simulated on a computer, but it is designed to be implemented by hand. [1] https://www.schneier.com/academic/solitaire/ https://www.schneier.com/academic/solitaire/

mangodrunk 3y ago

Checkout Solitaire by Bruce Schneier [1]. > In Neal Stephenson’s novel Cryptonomicon, the character Enoch Root describes a cryptosystem code-named “Pontifex” to another character named Randy Waterhouse, and later reveals that the steps of the algorithm are intended to be carried out using a deck of playing cards. These two characters go on to exchange several encrypted messages using this system. The system is called “Solitaire” (in the novel, “Pontifex” is a code name intended to temporarily conceal the fact that it employs a deck of cards) and I designed it to allow field agents to communicate securely without having to rely on electronics or having to carry incriminating tools. An agent might be in a situation where he just does not have access to a computer, or may be prosecuted if he has tools for secret communication. But a deck of cards…what harm is that? > Solitaire gets its security from the inherent randomness in a shuffled deck of cards. By manipulating this deck, a communicant can create a string of “random” letters that he then combines with his message. Of course Solitaire can be simulated on a computer, but it is designed to be implemented by hand. [1] https://www.schneier.com/academic/solitaire/ https://www.schneier.com/academic/solitaire/