Abstract: In recent years,blockchain has developed rapidly,and low transaction frequency has become an obstacle to the further development of blockchain.Lightning network,as one of the best solutions to the problem of blockchain transaction frequency,has the advantages of short confirmation time and low cost.However,there are also problems such as low channel capacity,high routing cost and channel congestion.Most of the existing optimization schemes use third-party custody to extend the transaction waiting time,but they cannot solve the channel congestion problem from the root.To solve these problems,this paper proposes a new lightning network optimization scheme.First,set up super nodes in the lightning network,and give super node tokens for mutual channel construction.Users can convert bitcoin into tokens through Ethereum Request for Comment protocol to enter the lightning network.Secondly,the concept of escape value is proposed.The user node chooses to join a super node by calculating the escape value.Finally,the improved landmark algorithm prunes the network channels,improves the network scalability,and solves the channel congestion problem.Simulation results show that this scheme has a good effect on network congestion and long path optimization time when the transaction volume in the lightning network is large.

Key words: Blockchain, Lightning network, Landmark, Off chain transaction, Super node, Privacy protection.