Creative Commons Attribution 4.0 International license
We consider the problem of secret leader election with accountability. Secret leader election protocols counter adaptive adversaries by keeping the identities of elected leaders secret until they choose to reveal themselves, but in existing protocols this means it is impossible to determine who was elected leader if they fail to act. This opens the door to undetectable withholding attacks, where leaders fail to act in order to slow the protocol or bias future elections in their favor. We formally define accountability (in weak and strong variants) for secret leader election protocols. We present three paradigms for adding accountability, using delay-based cryptography, enforced key revelation, or threshold committees, all of which ensure that after some time delay the result of the election becomes public. The paradigm can be chosen to balance trust assumptions, protocol efficiency, and the length of the delay before leaders are revealed. Along the way, we introduce several new cryptographic tools including re-randomizable timed commitments and timed VRFs.
@InProceedings{christ_et_al:LIPIcs.AFT.2024.1,
author = {Christ, Miranda and Choi, Kevin and McKelvie, Walter and Bonneau, Joseph and Malkin, Tal},
title = {{Accountable Secret Leader Election}},
booktitle = {6th Conference on Advances in Financial Technologies (AFT 2024)},
pages = {1:1--1:21},
series = {Leibniz International Proceedings in Informatics (LIPIcs)},
ISBN = {978-3-95977-345-4},
ISSN = {1868-8969},
year = {2024},
volume = {316},
editor = {B\"{o}hme, Rainer and Kiffer, Lucianna},
publisher = {Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
address = {Dagstuhl, Germany},
URL = {https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.AFT.2024.1},
URN = {urn:nbn:de:0030-drops-209378},
doi = {10.4230/LIPIcs.AFT.2024.1},
annote = {Keywords: Consensus Protocols, Single Secret Leader Election, Accountability}
}