Defending against the nothing-at-stake problem in multi-threaded blockchains
Abstract
In blockchain systems, the scarcity of a resource is used as a Sybil protection mechanism. In Proof-of-Work blockchains, that resource is computing power. In the event of a fork, the scarcity of this resource theoretically prevents miners from producing blocks on both branches of a fork. In Proof-of-Stake blockchains, because that resource is token stake, the computational cost of creating a block is negligible. In the event of a fork, and if no specific measures have been taken, rational block producers should extend both branches of the fork. In blockchains with sequential block production, a punishment mechanism known as slashing is often cited as a protection against the nothing-at-stake problem. However, in the context of a blockchain with parallel block production, it seems that slashing is not sufficient against the numerous divergence opportunities. In this paper, we propose a novel protection against the nothing-at-stake problem that takes the most out of BFT and Nakamoto-based consensus. By combining those approaches, we wish to scale up blockchains by allowing parallel block production without reconciliation.
Keywords
Cite
@article{arxiv.2302.10009,
title = {Defending against the nothing-at-stake problem in multi-threaded blockchains},
author = {Leonard Lys and Sebastien Forestier and Damir Vodenicarevic and Adrien Laversanne-Finot},
journal= {arXiv preprint arXiv:2302.10009},
year = {2023}
}