A Comprehensive Survey of Lightning Network Technology and Research

Bitcoin is the first decentralized digital currency built upon blockchain technology and has facilitated financial innovation and technological advancement. However, the growth in its popularity has uncovered the limitations of the blockchain technology, leading to issues such as transaction congestion, high transaction fees, and delayed confirmations. This has motivated the exploration of the Lightning Network, a payment channel network designed to enhance Bitcoin's scalability and transaction efficiency. Serving as a layer-2 protocol, the Lightning Network supports off-chain transactions, significantly reducing fees and enabling swift and cost-effective micro payments. This paper comprehensively examines the technology, open source implementations, and relevant research of the Bitcoin Lightning Network, covering key categories such as “network analysis,” “network security,” “payment routing,” “rebalancing,” and “network design and applications.” With the Lightning Network's increasing importance in the blockchain and financial domains, this survey provides a valuable resource for researchers seeking to explore this technology in greater depth.