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A Known-Plaintext Attack on Two-Key Triple Encryption

Part of the Lecture Notes in Computer Science book series (LNCS,volume 473)


A chosen-plaintext attack on two-key triple encryption noted by Merkle and Hellman is extended to a known-plaintext attack. The known-plaintext attack has lower memory requirements than the chosen-plaintext attack, but has a greater running time. The new attack is a significant improvement over a known-plaintext brute-force attack, but is still not seen as a serious threat to two-key triple encryption.

Key Words

  • triple encryption
  • cryptanalysis
  • DES


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  3. “Data Encryption Standard”, National Bureau of Standards (U.S.), Federal Information Processing Standards Publication (FIPS PUB) 46, National Technical Information Service, Springfield VA, 1977.

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  4. Internal study, BNR, Ottawa, 1989.

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© 1991 Springer-Verlag Berlin Heidelberg

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van Oorschot, P.C., Wiener, M.J. (1991). A Known-Plaintext Attack on Two-Key Triple Encryption. In: Damgård, I.B. (eds) Advances in Cryptology — EUROCRYPT ’90. EUROCRYPT 1990. Lecture Notes in Computer Science, vol 473. Springer, Berlin, Heidelberg.

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