Modified RC4 Algorithm for Improve Data Protection in Cloud Environment

Abstract

The rapid growth of digital technologies that depending on cloud computing has seriously increased the threats related to information security. This will certainly pose a major threat to the trust of users of the cloud environment. For this reason, the use of algorithms like Rivest Ciphers 4 (RC4) algorithms to encrypt data and then store in the cloud became essential issue. So, because of the simplicity and ease of RC4 algorithm and its suitability to encrypt most data form efficiently, it has been widely used. But, the RC4 algorithm suffers from some weaknesses in both of Key Schedule Algorithm (KSA) and Pseudo-Random Generation Algorithm (PRGA) stages. As, the intruder may be able to follow the traces and thus retrieve the key based on the internal state or the stream of output. There were a lot of modifications in many literature reviews to improve the security and performance of the RC4 algorithm. In this paper, the focus was placed on improving the RC4 algorithm in both of (KSA) and (PRGA) in order to increase the security level. The performance of our improved RC4 algorithm was tested and evaluated by increasing the randomness of the generated key. The experimental results prove that high security level for output based on the security average of ciphertext with various keys and various files size. Thus, get more security level for the personal data that is stored in the cloud.