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Compression and Information Leakage of Plaintext

Part of the Lecture Notes in Computer Science book series (LNCS,volume 2365)


Cryptosystems like AES and triple-DES are designed to encrypt a sequence of input bytes (the plaintext) into a sequence of output bytes (the ciphertext) in such a way that the output carries no information about that plaintext except its length. In recent years, concerns have been raised about ”side-channel” attacks on various cryptosystems—attacks that make use of some kind of leaked information about the cryptographic operations (e.g., power consumption or timing) to defeat them. In this paper, we describe a somewhat different kind of side-channel provided by data compression algorithms, yielding information about their inputs by the size of their outputs. The existence of some information about a compressor’s input in the size of its output is obvious; here, we discuss ways to use this apparently very small leak of information in surprisingly powerful ways.


  • Compression Ratio
  • Compression Algorithm
  • Side Channel
  • Stream Cipher
  • Information Leakage

These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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© 2002 Springer-Verlag Berlin Heidelberg

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Kelsey, J. (2002). Compression and Information Leakage of Plaintext. In: Daemen, J., Rijmen, V. (eds) Fast Software Encryption. FSE 2002. Lecture Notes in Computer Science, vol 2365. Springer, Berlin, Heidelberg.

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-44009-3

  • Online ISBN: 978-3-540-45661-2

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