Blockchain-based payment channel network: challenges and recent advances

The transaction processing speed of blockchains is not superior to that of the traditional financial system. Payment channel is one of the mainstream research directions to improve the performance of blockchain systems, and its functions include reducing transaction confirmation delay and increasing system transaction throughput. Payment channel networks allow a large number of transactions to be executed off-chain, which can reduce costs and facilitate blockchain scaling while keeping assets secure. As the most well-known work on payment channel networks, the Lightning Network is deployed on Bitcoin, and its demonstration of efficient performance and high economic benefits in practical operation has triggered a great deal of attention and research. This thesis systematizes the research work on payment channel networks represented by the Lightning Network, organize and analyze the potential attacks and improvement directions of the Lightning Network. Based on this, this thesis refines the existing research results into security attacks, privacy vulnerabilities and difficult-to-implement system assumptions, conducts detailed research on the key challenges of the lightning network, and compares the existing solutions. Finally, this thesis highlights the development potential of payment channel networks and identifies key issues that need to be addressed in order to advance the research on blockchain payment channel networks.