In this paper, using probability transition matrix, at first we revisit the work of Mantin on finding the probability distribution of RC4 permutation after the completion of KSA. After that, we extend the same idea to analyse the probabilities during any iteration of Pseudo Random Generation Algorithm. Next, we study the bias Zr = r (where Zr is the r-th output keystream bit), which is one of t...

Nowadays secured data sharing is a challenging process in cloud computing. This paper is to implement the secured data sharing in the online health communities. These online health communities continue to offer huge variety of medical information useful for medical practioners, system administrator and patients alike. In this paper the doctors and patients gets interact with each other. The pat...

In this paper we construct several tools for manipulating pools of biases in the analysis of RC4. Then, we show that optimized strategies can break WEP based on 4000 packets by assuming that the first bytes of plaintext are known for each packet. We describe similar attacks for WPA. Firstly, we describe a distinguisher for WPA of complexity 243 and advantage 0.5 which uses 240 packets. Then, ba...

RC4 encryption algorithm [3,12,16] was examined based on the text to be encrypted and the chosen key. It is a symmetric key algorithm and uses stream cipher i.e. data is being encrypted bit by bit. The same algorithm is used for both encryption and decryption. The data stream is XORed with the generated key sequence and the key stream is completely independent of the plaintext used. The weaknes...