Pipelet: Practical Streamlined Blockchain Protocol

Fueled by the increasing popularity of proof-of-stake blockchains, there has been increasing interest and progress in permissioned consensus protocols, which could provide a simpler alternative to existing protocols, such as Paxos and PBFT. In particular, the recently proposed Streamlet protocol provides a surprisingly simple and streamlined consensus protocol, which crystallizes years of research in simplifying and improving classic consensus protocols. While the simplicity of Streamlet is a major accomplishment, the protocol lacks certain practical features, such as working without synchronized clocks and supporting a stable block proposer, which limits its applicability. In this paper, we strive to approach the simplicity of Streamlet and the performance of PaLa, by introducing Pipelet, a streamlined version of the PaLa protocol. We formally prove the consistency and liveness of the Pipelet protocol in a partially synchronous communication model.