DAGGraph: Blockchain Suitable for Mobile Ad Hoc Networks

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.

Keywords

• blockchain; mobile ad hoc networks; clustering algorithm; consensus mechanism