Nova-BFT: A Replicated State Machine Protocol Supporting Multiple Fault Models

Cloud computing has greatly simplified the ways that the clients can access the resources, and the pain is the increasing complexity of the supporting system development and deployment. The Byzantine faults caused by software bugs, management misbehaviors have become a major source that affects the reliability of the system. The cost in communication, security and the robustness issue under attack result in that the Byzantine fault tolerance technology can’t be used directly in the practical systems which satisfy the benign fault model in most period of their lifecycle. How to satisfy the requirements of multiple fault-model has become an important problem in system design. To deal with the situation, we design Nova-BFT, a replicated state machine protocol which can support multiple fault models effectively. Nova-BFT fulfills performance robustness under attack by sacrificing some peak throughput in the fault-free scenario, and adaptively supports the benign fault model by adjusting configuration parameters. Experiments show that Nova-BFT prototype has a 4-5 kop/s throughput in the Byzantine fault model assumption and it can also fulfill the benign fault model requirements of most practical systems.