Cryptology ePrint Archive: Report 1999/008

Verifiable Encryption and Applications to Group Signatures and Signature Sharing

Jan Camenisch and Ivan Damgaard

Abstract: We generalize and improve the security and efficiency of the verifiable encryption scheme of Asokan et al., such that it can rely on more general assumptions, and can be proven secure without assuming random oracles. We show a new application of verifiable encryption to group signatures with separability, these schemes do not need special purpose keys but can work with a wide range of signature, identification, and encryption schemes already in use. Finally, we extend our basic primitive to verifiable threshold and group encryption. By encrypting digital signatures this way, one gets new solutions to the verifiable signature sharing problem.

Category / Keywords: public-key encryption, zero-knowledge protocols, verifiable signature sharing, group signatures

Publication Info: Appeared in the THEORY OF CRYPTOGRAPHY LIBRARY and has been included in the ePrint Archive.

Date: received March 23, 1999

Contact author: camenisch at brics dk

Available format(s): Postscript (PS) | Compressed Postscript (PS.GZ) | BibTeX Citation

Short URL: ia.cr/1999/008

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