TMD-Tradeoff and State Entropy Loss Considerations of Streamcipher MICKEY

  • Jin Hong
  • Woo-Hwan Kim
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3797)


We give three weaknesses of a recently proposed streamcipher MICKEY. A small class of weak keys is found and we show time-memory-data tradeoff is applicable. We also show that the state update function reduces entropy of the internal state as it is iterated, resulting in keystreams that start out differently but become merged together towards the end.


MICKEY stream cipher time memory data tradeoff internal state entropy weak key 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2005

Authors and Affiliations

  • Jin Hong
    • 1
  • Woo-Hwan Kim
    • 1
  1. 1.National Security Research InstituteDaejeonKorea

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