Performance Analysis of Encrypted Data Files by Improved RC4 (IRC4) and Original RC4

In Cryptography, RC4 is one of the best known stream cipher from the last two decades in steam cipher family and it’s already achieved the trust of many organizations after its code become public. Many Eminent researchers like Roos and et al. established that RC4 contains weakness and biasness in its internal stages. Most of the researcher feels that in KSA part of RC4 components contain most bias values related to the keys. If the KSA part generates strong output as for input of PRGA then resultant stream become more random. Already we proved and published that Improved RC4 (IRC4) gives better result compare to original RC4 in the generation of stream keys for encryption of any plaintext file. In this paper we generate two types of output stream files from the algorithm of IRC4 and original RC4 and implemented the both types of stream files to make encrypted files using same plaintext files and generates corresponding cipher text files. The two set of encrypted type files are testing through NIST Statistical package and from where we find out that IRC4 returns better result related to randomness of the cipher texts files, from where we can conclude that IRC4 algorithm generates more random stream and indirectly increase the security.