Performance Engineering of a Lightweight Fault Tolerance Framework

It is well-known that the Paxos algorithm can be used to build provably correct practical fault tolerant systems. In this thesis, a lightweight consensus framework - Paxos-Based Fault Tolerance (PFT) framework and its practical implementation is presented. It also includes how the system tolerates faults under practical conditions where the replicas might not be strictly homogeneous due to the asynchrony of their deployment environment. A comprehensive performance evaluation study is performed on the PFT framework. The approaches that can optimize the fault tolerance mechanisms under various practical scenarios are also discusse

Mysticeti: Low-Latency DAG Consensus with Fast Commit Path

We introduce Mysticeti-C a byzantine consensus protocol with low-latency and high resource efficiency. It leverages a DAG based on Threshold Clocks and incorporates innovations in pipelining and multiple leaders to reduce latency in the steady state and under crash failures. Mysticeti-FPC incorporates a fast commit path that has even lower latency. We prove the safety and liveness of the protocols in a byzantine context. We evaluate Mysticeti and compare it with state-of-the-art consensus and fast path protocols to demonstrate its low latency and resource efficiency, as well as more graceful degradation under crash failures. Mysticeti is the first byzantine protocol to achieve WAN latency of 0.5s for consensus commit, at a throughput of over 50k TPS that matches the state-of-the-art