BEAST: A fast block cipher for arbitrary blocksizes

  • Stefan Lucks
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT)


This paper describes BEAST, a new blockcipher for arbitrary size blocks. It is a Luby-Rackoff cipher and fast when the blocks are large. BEAST is assembled from cryptographic hash functions and stream ciphers. It is provably secure if these building blocks are secure.

For smartcard applications, a variant BEAST-RK is proposed, where the bulk operations can be done by the smartcard’s host without knowing the key. Only fast key-dependent operations remain to be done by the smartcard.


Block-cipher Luby-Rackoff pseudorandom permutation provably secure smartcard remote key 


  1. R. Anderson (1993) The Classification of Hash Functions, in Fourth IMA conference on cryptography and coding, 83–93.Google Scholar
  2. R. Anderson, E. Biham (1996) Two Practical and Provably Secure Block Ciphers: BEAR and LION, in Fast Software Encryption (ed. D. Gollmann ), Springer LNCS 1039, 113–120.CrossRefGoogle Scholar
  3. M. Blaze (1996) High-Bandwidth Encryption with Low-Bandwidth Smartcards, in Fast Software Encryption (ed. D. Gollmann ), Springer LNCS 1039, 33–40.CrossRefGoogle Scholar
  4. M. Luby, C. Rackoff (1988) How to construct pseudorandom permutations from pseudorandom functions, SIAM J. Computing, Vol. 17, No. 2, 373–386.zbMATHMathSciNetCrossRefGoogle Scholar
  5. S. Lucks (1996) Faster Luby-Rackoff Ciphers, in Fast Software Encryption (ed. D. Goll-mann ), Springer LNCS 1039, 189–203.CrossRefGoogle Scholar
  6. U. Maurer (1992) A Simplified and Generalized Treatment of Luby-Rackoff Pseudorandom Permutation Generators, in EuroCrypt ’82 (ed. R. Rueppel ), Springer LNCS 658, 239–255.Google Scholar
  7. P. Rogaway, D. Coppersmith (1993) A Software-Optimized Encryption Algorithm, in Fast Software Encryption (ed. R. Anderson ), Springer LNCS 809, 56–63.Google Scholar
  8. M. Roe (1994) Performance of Block Ciphers and Hash Functions–One Year Later, in Fast Software Encryption (ed. B. Preneel ), Springer LNCS 1008, 359–362.Google Scholar
  9. B. Schneier (1995) Applied Cryptography Wiley.Google Scholar

Copyright information

© IFIP International Federation for Information Processing 1996

Authors and Affiliations

  • Stefan Lucks
    • 1
  1. 1.Institut für Numerische und Angewandte MathematikGeorg—August—Universität GöttingenGeorg—August—Universität GöttingenGöttingenGermany

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