Practical Group Signatures without Random Oracles
نویسندگان
چکیده
We provide a construction for a group signature scheme that is provably secure in a universally com-posable framework, within the standard model with trusted parameters. Our proposed scheme is fairlysimple and its efficiency falls within small factors of the most efficient group signature schemes withprovable security in any model (including random oracles). Security of our constructions require newcryptographic assumptions, namely the Strong LRSW, EDH, and Strong SXDH assumptions. Evidencefor any assumption we introduce is provided by proving hardness in the generic group model.Our second contribution is the first definition of security for group signatures based on the simulata-bility of real protocol executions in an ideal setting that captures the basic properties of unforgeability,anonymity, unlinkability, and exculpability for group signature schemes.
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عنوان ژورنال:
- IACR Cryptology ePrint Archive
دوره 2005 شماره
صفحات -
تاریخ انتشار 2005