Abstract
In 1976 Diffie and Hellman first introduced their well-known key-exchange protocol which is based on exponentiation in the multiplicative group GF(p)* of integers relatively prime to a large primep (see [8]). Since then, this scheme has been extended to numerous other finite groups. Recently, Buchmann and Williams [2] introduced a version of the Diffie-Hellman protocol which uses the infrastructure of a real quadratic field. Theirs is the first such system not to require an underlying group structure, but rather a structure which is “almost” like that of a group. We give here a more detailed description of this scheme as well as state the required algorithms and considerations for their implementation.
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Communicated by Andrew M. Odlyzko
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Scheidler, R., Buchmann, J.A. & Williams, H.C. A key-exchange protocol using real quadratic fields. J. Cryptology 7, 171–199 (1994). https://doi.org/10.1007/BF02318548
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DOI: https://doi.org/10.1007/BF02318548