RC4D: A New Development of RC4 Encryption Algorithm

Cryptography is one of the essential methods for securing the information. In cryptography, there are many encryption algorithms; some of them strong where the others are broken. RC4 stream cipher one of the most common algorithms that are characterized by its speed in implementation does not need large storage space and has less complexity, but there are weaknesses in its output. Numerous researches work on the RC4 stream cipher to boost the security of it, to be strong enough. However, the biases in the output are still in most of the enhancement. The researchers claim that its swap function is responsible for those biases. They recommended to ignore some initial bytes from the key-stream output, to dispose of this before de facto encryption begins. This paper present new development over the RC4 algorithm (RC4D) via amendment in the first and second parts of the algorithm. In the first part, it increases the use of the key operations to obtain more considerable randomness, while adding one more random variable and use the Xor function in the second part. Thus, the experimental result of the NIST statistical tests and the distant-equalities statistical analysis shows the RC4D more robust than the original RC4.