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.

翻译：在区块链系统中，资源的稀缺性被用作女巫攻击保护机制。在工作量证明区块链中，该资源为计算能力；当发生分叉时，这种资源的稀缺性理论上可防止矿工在分叉的两个分支上同时产生区块。而在权益证明区块链中，由于该资源为代币权益，创建区块的计算成本可忽略不计。若未采取特定措施，发生分叉时理性区块生产者应同时扩展分叉的两个分支。在顺序出块的区块链中，常引用名为“罚没”的惩罚机制防范无利害关系问题。然而，在并行出块的区块链场景下，面对众多分叉机会，罚没机制似乎不足以应对。本文提出一种融合拜占庭容错与中本聪共识的新型防护方案，通过结合这两种方法，旨在实现无需协调的并行区块产出，从而提升区块链的扩展性。