Cryptology ePrint Archive: Report 2020/149

Vector Commitment Techniques and Applications to Verifiable Decentralized Storage

Matteo Campanelli and Dario Fiore and Nicola Greco and Dimitris Kolonelos and Luca Nizzardo

Abstract: Vector commitments with subvector openings (SVC) [Lai-Malavolta and Boneh-Bunz-Fisch, CRYPTO'19] allow one to open a committed vector at a set of positions with an opening of size independent of both the vector's length and the number of opened positions.

We propose a new SVC construction in groups of unknown order that, similarly to that of Boneh et al. has constant-size public parameters, commitments and openings, but in addition enjoys new features. First, our SVC has incremental aggregation: one can merge openings in a succinct way an unbounded number of times. Thanks to incremental aggregation we obtain: faster generation of openings via preprocessing, and a method to generate openings in a distributed way. Second, we propose efficient arguments of knowledge of subvector openings for our SVC, which immediately yields a keyless proof of storage with compact proofs.

Finally, we introduce and contruct Verifiable Decentralized Storage (VDS), a cryptographic primitive that allows to check the integrity of a file stored by a network of nodes in a distributed and decentralized way.

Category / Keywords: public-key cryptography / distributed cryptography, public-key cryptography, implementation, vector commitments

Date: received 10 Feb 2020

Contact author: matteo campanelli at gmail com,dario fiore@imdea org

Available format(s): PDF | BibTeX Citation

Version: 20200213:132208 (All versions of this report)

Short URL: ia.cr/2020/149


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