Nova: A robustness-oriented Byzantine Fault Tolerance protocol

With the increased complexity, malicious faults have become an important reasons that affect the reliability of the distributed system, especially the web-scale infrastructures, i.e. Amazon S3, Google AppEngine etc. Most such systems assume benign fault model which can't depict the malicious actions. The goal of Byzantine Fault Tolerance protocol (BFT for short) is to mask the malicious behaviors and it has been proved that some new proposed BFTs are suitable to support practical applications. But these BFTs still lack in robustness, a simple fault injection may cause significantly decrease in throughput or run in low throughput without violating the BFT safety property. We propose a new robustness-oriented BFT named Nova. Experiments show Nova has comparable throughput as PBFT in normal case and behave stably under the malicious attack. Compared with other BFTs, Nova can support practical applications more effectively.