A Group-Oriented Undeniable Signature Scheme for Unlikely Signers and Verifiers
نویسندگان
چکیده
Lee and Hwang proposed group-oriented undeniable signature schemes with a trusted center to guard against Langford’s attack. Unfortunately, there are some security weaknesses in Lee-Hwang’s schemes. Their schemes assume that the signers and verifier should honestly perform steps; otherwise their schemes will fail. To remove this impractical assumption and the corresponding problems, our improvement is proposed.
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