Cryptology ePrint Archive: Report 2009/527

An Efficient Adaptive-Deniable-Concurrent Non-malleable Commitment Scheme

Seiko Arita

Abstract: It is known that composable secure commitments, that is, concurrent non-malleable commitments exist in the plain model, based only on standard assumptions such as the existence of claw-free permutations or even one-way functions. Since being based on the plain model, the deniability of them is trivially satisfied, and especially the latter scheme satisfies also adaptivity, hence it is adaptive-deniable-concurrent non-malleable. However, those schemes cannot be said to be practically efficient. We show a practically efficient (string) adaptive-deniable-concurrent commitment scheme is possible under a global setup model, called global CRS-KR model.

Category / Keywords: cryptographic protocols

Date: received 2 Nov 2009, last revised 9 Mar 2010

Contact author: arita at iisec ac jp

Available formats: PDF | BibTeX Citation

Note: Some typos are corrected.

Version: 20100309:103950 (All versions of this report)

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