Attack by algorithm

[Teymour_aldridge]

Does anyone have any good reads about attacks on ciphers algorithmically, rather than heuristically; specifically, zero-knowledge attacks (where no knowledge beyond the type of cipher is known – i.e. no crib, etc)?
I’ve found some interesting things mostly around using simulated annealing and genetic algorithms to solve ciphers (efficient mechanisms to search through very large solution spaces very efficiently) in an old copy of “Numerical Recipes” that I have. Madness has mentioned some stuff around hill-climbing algorithms that I’m currently looking at.

[Madness]

I have written down (almost) everything I know into a “textbook” that explains how to break lots of things.
The current version is 450 pages and about half of that is made of ciphertexts for practice. Harry has the book
and is thinking of letting it out to cipherchallengers after the competition ends. The book does not give
code, but it does spell out some algorithms. Later sections build on the techniques of earlier sections.
I think it might be exactly what you are looking for. I’m not bragging; I just want to disseminate this
information so I can be free of it. I wouldn’t want it to be lost when I slip into dementia. Besides, I need
to free up some wet-RAM for other things, like listening to musics and petting cats.

A very useful place is practicalcryptography.com. They do a lot of classical ciphers and include Python code
for a lot of things. They don’t handle many ciphers like quagmires. Also, I have a better way of doing one or
two ciphers, and we can discuss them when they come up.

You should definitely read this paper:
Thomas Jakobsen, “A fast method for cryptanalysis of substitution ciphers,” Cryptologia 19:3 (1995) 265-274,
DOI: 10.1080/0161-119591883944
(His method can solve a mono substitution in ~100 steps, rather than 1000 generations in the genetic algorithm.)

[Philthy]

@Madness I would be very interested in getting a copy of your textbook, when the current challenge ends.
Thanks.
Philthy

[Author]

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