Tightly-Secure Signatures from Five-Move Identification Protocols

  title={Tightly-Secure Signatures from Five-Move Identification Protocols},
  author={Eike Kiltz and Julian Loss and Jiaxin Pan},
  journal={IACR Cryptol. ePrint Arch.},
We carry out a concrete security analysis of signature schemes obtained from five-move identification protocols via the Fiat-Shamir transform. Concretely, we obtain tightly-secure signatures based on the computational Diffie-Hellman (CDH), the short-exponent CDH, and the Factoring (FAC) assumptions. All our signature schemes have tight reductions to search problems, which is in stark contrast to all known signature schemes obtained from the classical Fiat-Shamir transform (based on three-move… 
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