A More Compact Representation of XTR Cryptosystem

  title={A More Compact Representation of XTR Cryptosystem},
  author={Masaaki Shirase and Dong-Guk Han and Y. Hibino and Howon Kim and Tsuyoshi Takagi},
  journal={IEICE Trans. Fundam. Electron. Commun. Comput. Sci.},
XTR is one of the most efficient public-key cryptosystems that allow us to compress the communication bandwidth of their ciphertext. The compact representation can be achieved by deploying a subgroup Fq2 of extension field Fq6, so that the compression ratio of XTR cryptosystem is 1/3. On the other hand, Dijk et al. proposed an efficient public-key cryptosystem using a torus over Fq30 whose compression ratio is 4/15. It is an open problem to construct an efficient public-key cryptosystem whose… 

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