Cryptology

The word cryptology stems from the Greek kryptos, “hidden,” and logos, “word.” Cryptology is the science of secure communications. Cryptology comprises cryptography and cryptanalysis, the former deals with methods to ensure the security, secrecy, or authenticity; the latter is concerned with methods of breaking secret messages or forging signals that will be accepted as authentic. In this chapter we will be concentrating mainly on those aspects of cryptography that rely on mathematical, in particular algebraic, techniques and tools.