### Recurring Contingent Payment for Proofs of Retrievability

Aydin Abadi, Steven J. Murdoch, and Thomas Zacharias

##### Abstract

Fair exchange protocols let two mutually distrusted parties exchange digital data in a way that neither can cheat. At CCS 2017, Campanelli et al. proposed two blockchain-based protocols for the fair exchange of digital coins and a certain service, i.e., “proofs of retrievability” (PoR), that take place between a buyer and seller. In this work, we identify two serious issues of these schemes; namely, (1) a malicious client can waste the seller’s resources, and (2) real-time leakage of information to non-participants in the exchange. To rectify the issues, we propose “recurring contingent PoR payment” (RC-PoR-P). It lets the fair exchange reoccur while ensuring that the seller’s resources are not wasted, and the parties’ privacy is preserved. We implemented the RC- PoR-P. Our cost analysis indicates that the RC-PoR-P is efficient. The RC-PoR-P is the first of its kind that offers all the above features.

Available format(s)
Category
Cryptographic protocols
Publication info
Preprint. MINOR revision.
Keywords
Proofs of RetrievabilityFair ExchangeBlockchainSmart contract
Contact author(s)
aydin abadi @ ucl ac uk
s murdoch @ ucl ac uk
thomas zacharias @ ed ac uk
History
Short URL
https://ia.cr/2021/1145

CC BY

BibTeX

@misc{cryptoeprint:2021/1145,
author = {Aydin Abadi and Steven J.  Murdoch and Thomas Zacharias},
title = {Recurring Contingent Payment for Proofs of Retrievability},
howpublished = {Cryptology ePrint Archive, Paper 2021/1145},
year = {2021},
note = {\url{https://eprint.iacr.org/2021/1145}},
url = {https://eprint.iacr.org/2021/1145}
}

Note: In order to protect the privacy of readers, eprint.iacr.org does not use cookies or embedded third party content.