MWPoW+: A Strong Consensus Protocol for Intra-Shard Consensus in Blockchain Sharding

Blockchain sharding splits a blockchain into several shards where consensus is reached at the shard level rather than over entire blockchain. It improves transaction throughput and reduces computational resources required of individual nodes. But derivation trustworthy within becomes an issue as longest chain based mechanisms used in conventional blockchains can no longer be used. Instead, vote-based mechanism must employed. However, existing Byzantine fault tolerance protocols do not offer sufficient security guarantees for sharded blockchains. First, when to support only one block allowed time (binary consensus), these are susceptible progress-hindering attacks (i.e., unable reach consensus). Second, stronger type multiple concurrent blocks (strong their adversary nodes low. This article proposes new protocol address all issues. We call MWPoW +, its basic framework on Multiple Winners Proof Work (MWPoW) but includes issues mentioned previously. MWPoW+ strong consensus, asynchronous synchronous communication. prove that it tolerate up f < n /2 n-node system if using binary does suffer from attacks.