### Design and Implementation of Proposed B-R Encryption Algorithm

*IRAQI JOURNAL OF COMPUTERS, COMMUNICATIONS, CONTROL AND SYSTEMS ENGINEERING*

2009, Volume 9, Issue 1, Pages 34-50

2009, Volume 9, Issue 1, Pages 34-50

#### Abstract

Abstract:In this paper, a 128-bit block cipher B-R encryption algorithm is proposed which is an evolutionary improvement of 64-bits Blowfish designed to meet the requirements of the Advanced Encryption Standard. It is compact, speedy, simple and easy to understand. It is a Feistel network, iterating a simple encryption function 16 times and the key can be any length up to 128 bytes. The B-R reduced the memory requirement by using two S-boxes each of which of size 259 bytes instead of four S-boxes each of size 1024 bytes in Blowfish algorithm ,so that the total size of S-box of B-R is 518 bytes while the size of S-box of Blowfish is 4096 bytes, without compromising security. Using several techniques will increase the security of B-R algorithm. Block size and key length were increased and RC6 as complex function was used after the F-function to avoid a symmetric to the output of S-boxes A desirable property of an encryption algorithm is that a small change in either the plaintext or the key should produce a significant change in the ciphertext. This is so called Avalanche Effect. An average of Avalanche Effect of proposal B-R is about 65.42857 % if only one bit in the key is changed while for Blowfish the average of Avalanche Effect is about 28.714286. On the other hand the average of Avalanche Effect is about 60.7143 in RC6 Algorithm.

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