计算机科学与探索 ›› 2024, Vol. 18 ›› Issue (1): 252-264.DOI: 10.3778/j.issn.1673-9418.2211070

• 网络·安全 • 上一篇    下一篇

DAGGraph: 适合移动自组网的区块链

张文韬,黄建华,顾彬,宁宇豪,宫在为   

  1. 华东理工大学 信息科学与工程学院,上海 200237
  • 出版日期:2024-01-01 发布日期:2024-01-01

DAGGraph: Blockchain Suitable for Mobile Ad Hoc Networks

ZHANG Wentao, HUANG Jianhua, GU Bin, NING Yuhao, GONG Zaiwei   

  1. School of Information Science and Engineering, East China University of Science and Technology, Shanghai 200237, China
  • Online:2024-01-01 Published:2024-01-01

摘要: 针对区块链与移动自组网结合所面临的挑战,采用有向无环图(DAG)结构适配移动性引发的网络分裂,提出一种基于DAG的系统模型DAGGraph。首先,对分簇算法进行优化,提出了簇内节点密度数量限制算法,从而有效解决了簇内节点数量不受控增加带来的吞吐量减小和能耗增加问题;其次,针对移动自组网节点快速移动引起的网络拆分与合并问题,提出了基于簇首间数据同步的区块恢复算法,通过DAG结构保留所有节点产生的合法区块,在网络合并时由原簇首交换产生的区块分支,实现了对区块分支的同步和恢复;最后,提出了一种简化的区块上链算法,在内部节点可信的前提下简化了区块的上链流程,减小了移动环境下区块传播产生的误差,缩短了区块的确认时间,提高了系统吞吐量。安全性分析表明,系统可以抵御针对区块链的常见攻击,并可以抵御针对移动自组网的拒绝服务攻击。仿真实验结果表明,DAGGraph的时延和吞吐量性能在大部分情况下优于已有的物联网区块链解决方案。

关键词: 区块链, 移动自组网, 分簇算法, 共识机制

Abstract: Aiming at the challenges faced by the combination of blockchain and mobile ad hoc networks, a system model DAGGraph based on DAG (directed acyclic graph) is proposed, which adopts the DAG structure to adapt to the network split caused by mobility. Firstly, the clustering algorithm is optimized, and an algorithm for limiting the density of nodes in the cluster is proposed, which effectively solves the problem of throughput reduction and energy consumption increase caused by the uncontrolled increase of the number of nodes in the cluster. Secondly, for network splitting and merging caused by the rapid movement of the nodes, a block recovery algorithm based on data synchronization between cluster heads is proposed. The legal blocks generated by all nodes are preserved through DAG. When the network is merged, the original cluster heads exchange their generated block branches, realizing the recovery of the block branches. Finally, a simplified block appending algorithm is proposed, which simplifies the block appending process on the premise that the internal nodes are trusted, reduces the error caused by block propagation in the mobile environment, shortens the block confirmation time, and improves the system throughput. Security analysis shows that DAGGraph can resist common attacks against blockchain, and resist denial-of-service attacks against mobile ad hoc networks. Simulation results show that the latency and throughput of DAGGraph are better than existing IoT blockchain solutions in most cases.

Key words: blockchain, mobile ad hoc networks, clustering algorithm, consensus mechanism