Paper 2019/197
Non-interactive Cryptographic Timestamping based on Verifiable Delay Functions
Esteban Landerreche, Marc Stevens, and Christian Schaffner
Abstract
We present the first treatment of non-interactive publicly-verifiable timestamping schemes in the Universal Composability framework. Similar to a simple construction by Mahmoody et al., we use non-parallelizable computational work that relates to elapsed time to avoid previous impossibility results on non-interactive timestamping. We extend these ideas to the UC-framework and show how to model verifiable delay functions (VDF) related to a global clock, and non-interactive timestamping, in the UC-framework. Furthermore, we present new constructions that are substantial improvements over Mahmoody et al.’s construction, such that any forged timestamps by the adversary are now limited to within a certain time-window that depends only on its ratio to compute VDFs more quickly and the time-window of corruption. Finally, we discuss natural applications for our construction in decentralized protocols.
Metadata
- Available format(s)
-
PDF
- Publication info
- Preprint. MINOR revision.
- Keywords
- non-interactive cryptographic timestampinguniversal composabilityverifiable delay functionstime-lock cryptography
- Contact author(s)
- esteban @ cwi nl
- History
- 2019-02-27: revised
- 2019-02-27: received
- See all versions
- Short URL
- https://ia.cr/2019/197
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2019/197,
author = {Esteban Landerreche and Marc Stevens and Christian Schaffner},
title = {Non-interactive Cryptographic Timestamping based on Verifiable Delay Functions},
howpublished = {Cryptology {ePrint} Archive, Paper 2019/197},
year = {2019},
url = {https://eprint.iacr.org/2019/197}
}