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XMX: A firmware-oriented block cipher based on modular multiplications

Part of the Lecture Notes in Computer Science book series (LNCS,volume 1267)


This paper presents xmx, a new symmetric block cipher optimized for public-key libraries and microcontrollers with arithmetic co-processors, xmx has no S-boxes and uses only modular multiplications and xors. The complete scheme can be described by a couple of compact formulae that offer several interesting time-space trade-offs (number of rounds/key-size for constant security).

In practice, xmx appears to be tiny and fast:136 code bytes and a 121 kilo-bits/second throughput on a Siemens SLE44CR80s smart-card (5 MHz oscillator).


  • Smart Card
  • Diffusion Means
  • Block Cipher
  • Modular Multiplication
  • Data Encryption Standard

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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© 1997 Springer-Verlag

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M’RaÏhi, D., Naccache, D., Stern, J., Vaudenay, S. (1997). XMX: A firmware-oriented block cipher based on modular multiplications. In: Biham, E. (eds) Fast Software Encryption. FSE 1997. Lecture Notes in Computer Science, vol 1267. Springer, Berlin, Heidelberg.

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-63247-4

  • Online ISBN: 978-3-540-69243-0

  • eBook Packages: Springer Book Archive