A Multi-path Routing Algorithm For Blockchain Payment Channel Networks

As a disruptive and innovative technology,blockchain solves the problem of trust in permissionless networks and has broad application prospects in digital finance,Internet of Things,supply chain management and many other fields.In the research of blockchain technology,payment channel network is considered as one of the most promising methods to solve the scalability problem of blockchain.As the most widely used payment channel network,Lightning Network has attracted a large number of users and achieved great development in recent years.However,the development characteristics and security of this new thing need to be analyzed.The existing analysis works of Lightning Network are all based on outdated and limited data,which is not enough to reflect the development characteristics of Lightning Network.In addition,the transaction success rate of existing routing algorithms in payment channel networks is unsatisfactory,and the transaction fee is seldom considered.To address the above problems,this paper makes a systematic and comprehensive analysis of Lightning Network,including the network topology,development trend and charging strategy based on the latest data of Lightning Network.We propose a multipath routing algorithm in payment channel networks based on genetic algorithm to minimize transaction fee.Our experiment shows the effectiveness of the proposed algorithm in improving transaction success rate and reducing transaction fee.In this paper,we build an analysis framework of Lightning Network based on the latest channel data up to January 2022.We analyze the basic attributes,connected components and typical feature distributions based on the current topology of Lightning Network.Statistics show that Lightning Network conforms to the structural characteristics of scale-free network,and a few central nodes occupy most resources of the network.We analyze the development of Lightning Network in each period based on the channel data since it was released four years ago.The analysis shows that the overall scale of Lightning Network is increasing,and its change is closely related to the improvement of payment channel network technology and the popular application of bitcoin transaction.We analyze the charging strategy of nodes in Lightning Network,and makes a comparative analysis on the on-chain and off-chain Bitcoin transactions based on the simulated transaction experiment.At present,the transaction fee in Lightning Network is very low,which is far lower than the transaction cost on chain.This paper proposes a multipath routing protocol applicable to blockchain payment channel networks,which allows users to forward transactions through multiple paths.The algorithm aims at minimizing the transaction fee and can be applied to different payment channel networks.The routing protocol is based on a genetic algorithm for multipath problems.The algorithm designs genetic operators such as selection,crossover and mutation to determine the optimal number of paths,routing nodes and transaction amount allocation,so as to obtain a low-cost solution with high success rate.We construct a simulated large-scale payment channel network based on the real Lightning Network structure to evaluate the proposed multipath routing algorithm.Through detailed experimental analysis,it is proved that the proposed algorithm can reduce the transaction fee by 33.56%on average and increase the transaction success rate by 5 percentage points compared with the single path algorithm in the lightning network topology.The proposed multipath routing algorithm is more suitable for the payment channel network with high proportion fee,especially for large payment in unbalanced channel conditions.