mdubard/basiccrypto

Contains two files: one that does a textbook RSA decoding, and one that decodes a phrase encoded using an unknown Vigenere cipher.

Basic Cryptology

TextbookRSA.java uses force to identify the message, that is, the number that fits the designated gcd. For more information on RSA, refer to http://searchsecurity.techtarget.com/definition/RSA.

Vigenere.java is given an encrypted phrase. It then identifies the phrase used to encode the original message by going through all possibilities, and stopping on the phrase that matches common frequency levels of letters used in the English language. (For example, a "decoded" message with many q's and z's would most likely be wrong.) For more information on the Vigenere Cipher, refer to http://www.counton.org/explorer/codebreaking/vigenere-cipher.php.