无线网络中区块链共识算法的开销分析

Overhead Analysis of Blockchain Consensus Algorithm in Wireless Networks

选取工作量证明(PoW)和实用拜占庭容错(PBFT)作为公/私链代表,对比分析了两者在无线网络中的系统资源消耗,为区块链类型的选择提供合理评估.首先,建立公平统一的网络模型和区块链标准流程;然后,考虑无线网络传输失败导致的区块丢失,推导分析了相应的PoW分叉和PBFT视图更换概率;最后,分析了无线网络规模对PoW和PBFT的通信开销和算力开销的影响.仿真结果表明,PBFT的算力开销远小于Po W,但PBFT的通信开销受节点规模的影响较大,可扩展性较差;PoW的通信开销受节点规模的影响相对平缓,可扩展性相对较好.

In order to provide a reasonable evaluation for the choice of blockchain type,proof of work(PoW)and practical Byzantine fault tolerance(PBFT)are treated as the benchmark of typical public and private chains for blockchain selection evaluation,and the overhead of blockchain in wireless networks is studied.Firstly,a fair network system and standard blockchain procedure have been provided,and then,considering the impact of block loss generated by transmission failure,the forking probability in PoW and view change probability in PBFT have been analyzed.Moreover,how network scale affects the communication and computation overhead in PoW and PBFT has been also investigated.Finally,the experimental results show that the computational overhead of PBFT is much smaller than that of PoW,the communication overhead of PBFT is greatly affected by the scale of the node,and thus the scalability of PBFT is poor.In contrast,the overhead of PoW communication is affected by the network scale linearly,and the scalability is much better compared with PBFT.