Improve Data Encryption Standard using 256Bit key Length

Abstract

Network security is becoming more crucial as the volume of data being exchanged on the internet. A more practical way to protect information is to alter it so that only an authorized receiver can understand it. Security of data and telecommunication can be done by a technique called cryptography. In this thesis Data Encryption Standard algorithm has been improved. Improved algorithm uses input data 512bit and key of 256bit length to encrypt the data. It uses S-boxes similar to those of Data Encryption Standard [DES] in a new structure that simultaneously allows a more rapid avalanche. The aim is to develop stronger encryption system that results in minimum execution time and maximum security. security analysis is applied on proposed algorithm using National Institute of Standards and Technology [NIST] statistical test tool with cryptool ,the results show that reasonable strength.