Structure-preserving signatures are used pervasively in group signatures, group encryptions, blind signatures, proxy signatures and many other anonymous credential applications. Our work directly leads to improvements in these schemes. Moreover, the improvements are usually of a higher multiplicative factor order, as these constructions use Groth-Sahai NIZK proofs for zero-knowledge verification of pairing-product equations.
We also give our construction under the more general and standard $\D_k$-MDDH (Matrix-DDH) assumption. The signature size in our scheme is $3k+2$ elements in one group, and one element in the other. The number of pairing product equations required for verification is only $2k$, whereas the earlier schemes required at least $2k+1$ equations.Category / Keywords: QA-NIZK, SXDH, MDDH, group signatures, blind signatures, Cramer-Shoup encryption Original Publication (in the same form): IACR-PKC-2017 Date: received 10 Jan 2017, last revised 11 Jan 2017 Contact author: csjutla at us ibm com, arnabr@gmail com Available format(s): PDF | BibTeX Citation Version: 20170113:181323 (All versions of this report) Short URL: ia.cr/2017/025 Discussion forum: Show discussion | Start new discussion