Editing RC4 (section)

===Klein's attack===
In 2005, Andreas Klein presented an analysis of the RC4 stream cipher, showing more correlations between the RC4 keystream and the key.<ref>A. Klein, Attacks on the RC4 stream cipher, Designs, Codes and Cryptography (2008) 48:269–286.</ref> [[Erik Tews]], [[Ralf-Philipp Weinmann]], and [[Andrei Pychkine]] used this analysis to create aircrack-ptw, a tool that cracks 104-bit RC4 used in 128-bit WEP in under a minute.<ref>Erik Tews, Ralf-Philipp Weinmann, Andrei Pyshkin. [//eprint.iacr.org/2007/120 Breaking 104-bit WEP in under a minute].</ref> Whereas the Fluhrer, Mantin, and Shamir attack used around 10&nbsp;million messages, aircrack-ptw can break 104-bit keys in 40,000 frames with 50% probability, or in 85,000 frames with 95% probability.