Tagged Questions
2
votes
2answers
290 views
How to get the keyword from a keyword cipher?
I was given a ciphertext and now I am trying to break it via looking for the keyword.
This is a keyword cipher. So:
PlainEnglish: ABCDEFGHIJKLMNOPQRSTUVWXYZ
If ...
6
votes
1answer
366 views
How to deduce enigma settings given a partial plaintext?
Assuming some large block of text is encrypted with an enigma machine and I only know a small subset of letters before and after encryption, how do I go about figuring out the enigma settings from ...
5
votes
2answers
843 views
How to attack a classical cipher using known partial plaintext?
I have a ciphertext generated by a classical cipher. I do not know what was cipher used to generate it. I do however have the beginning of the plaintext.
What are the cryptanalysis approaches for ...
3
votes
1answer
228 views
What is the best method to determine the language used in a monoalphabetic substitution cipher?
Working on a cipher (which I assume to be a mono-alphabetic substitution cipher due to the letter frequency) I struggle with the fact that I don't know which language the plain text is written in. ...
7
votes
1answer
3k views
How does the index of coincidence work in the Kasiki test?
I'm starting to learn about cryptanalysis and I am having a bit of difficulty understanding the Kasiski test's index of coincidence. I have a book (Cryptography Theory And Practice by Douglas Stinson) ...