These notes should help for an in-depth understanding of the paper [1] by Klein and [2] by Tews, Weinmann and Pyshkin. 1 Notation n 256; S array containing the numbers {0, ..., n− 1} in some order. Each number is present only once. S is also called a permutation; Si RC4 internal permutation S after the i-th RC4 round. 1 ≤ i ≤ n corresponds to the key setup algorithm, while i > n is the key stre...

This paper develops a new algorithm to improve the security of RC4. Given that RC4 cipher is widely used in the wireless communication and has some weaknesses in the security of RC4 cipher, our idea is based on the combination of the RC4 and the poly alphabetic cipher Vigenère to give a new and more secure algorithm which we called VRC4. In this technique the plain text is encrypted using the c...

RC4 is a stream cipher designed by Ron Rivest in 1987, and is widely used in various applications. WPA is one of these applications, where TKIP is used for a key generation procedure to avoid weak IV generated by WEP. In FSE 2014, two different attacks against WPA were proposed by Sen Gupta et al. and Paterson et al. Both focused correlations between the keystream bytes and the first 3 bytes of...

RC4 was used as an encryption algorithm in WEP(Wired Equivalent Privacy) protocol that is a standardized for 802.11 wireless network. A few attacks followed, indicating certain weakness in the design. In this paper, we proposed a new variant of RC4 stream cipher. The new version of the cipher does not only appear to be more secure, but its keystream also has large period, large complexity and g...

RC4+ stream cipher was proposed by Maitra et. al. at Indocrypt 2008. It was claimed by the authors that this new stream cipher is designed to overcome all the weaknesses reported on the alleged RC4 stream cipher. In the design specifications of RC4+, the authors make use of an 8-bit design parameter called pad which is fixed to the value 0xAA. The first Distinguishing Attack on RC4+ based on th...

RC4 is the most widely used stream cipher around. So, it is important that it runs cost effectively, with minimum encryption time. In other words, it should give higher throughput. In this paper, a mechanism is proposed to improve the throughput of RC4 algorithm in multicore processors using multithreading. The proposed mechanism does not parallelize RC4, instead it introduces a way that multit...

The paper presents a new statistical bias in the distribution of the first two output bytes of the RC4 keystream generator. The number of outputs required to reliably distinguish RC4 outputs from random strings using this bias is only 2 bytes. Most importantly, the bias does not disappear even if the initial 256 bytes are dropped. This paper also proposes a new pseudorandom bit generator, named...

Cryptography is the technique which is utilized for secure communication over the network. By using Cryptography technique readable information is converted into an unreadable form. Cryptography is used to protect data from unauthorized access. Universality of security in modern internet based application is an explicit motivation to contribute in the area of Information Security. Multimedia da...