DAG-based consensus has attracted significant interest due to its high throughput in asynchronous network settings. However, existing protocols such as DAG-rider (Keidar et al., PODC 2021) and ``Narwhal and Tusk'' (Danezis et al., Eurosys 2022) face two undesired practical issues: (1) high transaction latency and (2) high cost to verify transaction outcomes. To address (1), this work introduces a novel commit rule based on the Unspent Transaction Output (UTXO) Data Model, which allows a node to predict the transaction results before triggering the commitment. We propose a new consensus algorithm named ``Board and Clerk'', which reduces the transaction latency by half for roughly 50% of transactions. As the tolerance for faults escalates, more transactions can partake in this latency reduction. In addition, we also propose the Hyper-Block Model with two flexible proposing strategies to tackle (2): blocking and non-blocking. Using our proposed strategies, each node first predicts the transaction results if its proposal is committed and packs this result as a commitment in its proposal. The hyper-block packs the signature of the proposal and the outputs of the consensus layer together in order to prove the transaction results.
翻译:基于有向无环图(DAG)的共识协议因其在异步网络环境下具有高吞吐量而备受关注。然而,现有协议如DAG-rider(Keidar等人,PODC 2021)和"Narwhal and Tusk"(Danezis等人,Eurosys 2022)面临两个实际应用中的缺陷:(1)交易延迟较高,(2)验证交易结果成本过高。针对问题(1),本文提出一种基于未花费交易输出(UTXO)数据模型的新型提交规则,允许节点在触发提交操作前预判交易结果。我们设计了名为"Board and Clerk"的新共识算法,可使约50%交易的延迟降低一半。随着容错能力的提升,更多交易能够享受这种延迟优化。针对问题(2),我们进一步提出超块模型(Hyper-Block Model)及两种灵活的提案策略:阻塞式与非阻塞式。通过所提策略,每个节点首先预判其提案被提交后的交易结果,并将该结果作为承诺打包至提案中。超块通过整合提案签名与共识层输出,实现对交易结果的可验证证明。