RC4 is one of the most widely used stream cipher due to its simplicity, speed and efficiency. In this paper we have presented a chronological survey of RC4 stream cipher demonstrating its weaknesses followed by the various RC4 enhancements from the literature. From the recently observed cryptanalytic attempts on RC4 it is established that innovative research efforts are required to develop secure RC4 algorithm, which can remove the weaknesses of RC4, such as biased bytes, key collisions, and

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... recovery attacks specifically on WEP and WPA. These flaws in RC4 are offering open challenge for developers. Hence our chronological survey corroborates the fact that even though researchers are working on RC4 stream cipher since last two decades, it still offers a plethora of research issues related to statistical weaknesses in either state or keystream.