Block Cryptosystem Using Two Dimensional Hybrid Cellular Automata

INTRODUCTION

Since the development of computers there has been strong demand for means to protect information and to provide various security services. The main aspects of information security are privacy, data integnty, authentication, and non-repudiation.

Cryptography is the science, or some would say the art, of secret codes. In its broadest sense cryptography addresses a number of practical problems

confidentiality, keeping messages secret;origin

authentication, verlfying a message’ssource;

integrity, assuring that a message has not been modified; and

key management, distributing the secret “keys” for cryptographic algorithms.

This survey focuses on encryption algorithms, the low-level, step-by-step transformations on messages that address these problems, as well as applications that involve encryption.

Encryption has long been used by militaries and governments to facilitate secret communication. Encryption is now used in protecting information within many kinds of civilian systems, such as computers, networks (e.g. the Internet e-commerce), mobile telephones, wireless microphones, wireless intercom systems, Bluetooth devices and bank automatic teller machines. Encryption is also used in digital rights management to prevent unauthorized use or reproduction of copyrighted material and in software also to protect against reverse engineering .

Standards and cryptographic software and hardware to perform encryption are widely available, but successfully using encryption to ensure security may be a challenging problem. A single slip-up in system design or execution can allow successful attacks.

PROBLEM STATEMENT

 With the ever-increasing growth of data communication, the need for security and privacy has become a strong necessity. In these conditions, the necessity of new powerful encryption techniques becomes a crucial issue.

 File compression can significantly reduce the size of a file (or group of files). Smaller files take up...