A public key cryptosystem and a signature scheme based on discrete logarithms

  title={A public key cryptosystem and a signature scheme based on discrete logarithms},
  author={Taher El Gamal},
  journal={IEEE Trans. Inf. Theory},
  • Taher El Gamal
  • Published 1984
  • Computer Science, Mathematics
  • IEEE Trans. Inf. Theory
-A new signature scheme is proposed, together with an imple- mentation of the Diffie-Hellman key distribution scheme that achieves a public key cryptosystem. The security of both systems relies on the difficulty of computing discrete logarithms over finite fields. 

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Discrete Logarithms in Finite Fields and Their Cryptographic Significance

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  • Computer Science, Mathematics
  • 1984
This paper surveys and analyzes known algorithms in this area, with special attention devoted to algorithms for the fields GF(2n), finding that in order to be safe from attacks using these algorithms, the value of n for which GF( 2n) is used in a cryptosystem has to be very large and carefully chosen.

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A subexponential-time algorithm for computing discrete logarithms over GF(p2)

  • Taher El Gamal
  • Computer Science, Mathematics
    IEEE Trans. Inf. Theory
  • 1985
An algorithm for computing discrete logarithms over GF(p*), where p is a prime, in subexponential time is described, which uses quadratic fields as the appropriate algebraic structure.

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  • L. Adleman
  • Computer Science, Mathematics
    20th Annual Symposium on Foundations of Computer Science (sfcs 1979)
  • 1979
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  • C. Schnorr
  • Mathematics, Computer Science
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