Design and Analysis of Stream Cipher for Network Security

This paper mainly analysis and describe the design issue of stream ciphers in Network security as the streams are widely used to protecting the privacy of digital information. A variety of attacks against stream cipher exist;(algebraic and so on). These attacks have been very successful against a variety of stream ciphers. So in this paper efforts have been done to design and analyze stream ciphers. The main contribution is to design new stream ciphers through analysis of the algebraic immunity of Boolean functions and S-Boxes. In this paper, the cryptographic properties of non-linear transformation have been used for designing of stream ciphers Many LFSR (Linear feedback Shift Register) based stream ciphers use non-linear Boolean function to destroy the linearity of the LFSR(s) output. Many of these designs have been broken by algebraic attacks. Here we analyze a popular and cryptographically significant class of non-linear Boolean functions for their resistance to algebraic attacks.