Enhancing Ethereum PoA Clique Network with DAG-based BFT Consensus

Proof-of-Authority (PoA) is one of the popular blockchain consensus protocols, particularly for permissioned blockchains. However, PoA (as in Clique) still faces performance scalability issues. Its leader-based design restricts throughput and results in resource inefficiency, as it permits only one block to be accepted in each round, discarding all other concurrently proposed blocks in the same round. In this paper, we introduce DaPoA, an effort to enhance the Ethereum PoA Clique network to improve its performance scalability. The main idea of DaPoA is that it follows a parallel leader architecture that allows multiple sealers to propose their blocks in each round, which are then accepted in the same round. To achieve this, DaPoA employs a state-of-the-art directed acyclic graph (DAG)-based Byzantine Fault Tolerant (BFT) consensus algorithm, which enables parallel block proposals for high scalability with leader-less design. We have implemented and evaluated DaPoA on top of the Ethereum PoA Clique to demonstrate its performance scalability. In our setting of eight nodes, DaPoA achieves a 2.47 x higher throughput and 5.76x lower latency compared to Clique.