-1
votes
1answer
101 views

Chosen Plaintext Attacks

Assuming the ability to launch Chosen Plaintext Attacks (CPA), how many oracle calls an attacker needs to break the affine cipher? and how
-5
votes
1answer
97 views

My Hand Cipher, Can some one tell if it secure [closed]

In easy steps how it works, Convert txt to numbers . mod 1-26. Generate random numbers (By my other cipher) equal to plain txt. Write random numbers under txt numbers. txt= LOI - txt number= 12 15 ...
2
votes
2answers
291 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
3answers
2k views

Encryption/ciphers/codes in Chinese

I am quite curious as to how you can perform simple encryption for the Chinese language. Saw a similar question related to encryption/Chinese here: About cryptography in a character language, ...
2
votes
2answers
254 views

How can one break a monoalphbetic substitution chipher at pseudorandom text?

Does anybody know how to break monoalphbetic substitution cipher, if it is applied to some pseudorandom text (for example to some surrogate key filed in a database)? Let us assume that we have only ...
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. ...
-4
votes
1answer
213 views
10
votes
4answers
473 views

About Cryptography in a Character Language

Suppose I had a message in Chinese (or another non-phonetic language) and I wanted to encipher it. Some of the simplest encryptions in English are substitution ciphers, but such ciphers don't seem ...