Introduction to Cryptography

Overview of the field of the Cryptology

Cryptology can be basically introduced as a study of codes and as an art of learning to write and solve them. Basically it can be divided in to two parts, and they are Cryptography and Cryptoanalysis.

The filed of cryptography is the art of writing codes. It converts plain texts in to cypher texts.

The other is Crypto analysis.  In this area you learn to break the code to convert the cypher text to plain text.

Few basic facts about Cryptography

Ancient cryptography : The earliest signs of cryptography could be seen in the Egyptian time where letter based encryption schemes were used.

Symmetric ciphers : All the encryption schemes from ancient times until 1976 were symmetric   ciphers.

Asymmetricciphers:In1976public-key(orasymmetric)cryptographywasopenly proposedbyDiffie,HellmanandMerkle.