Improved lightweight node storage solutions in blockchain

Lightweight nodes in blockchain systems face challenges in terms of dependence, verification efficiency, and security due to their limited storage and growing data volume. This article focuses on two types of lightweight nodes: lightweight clients (e.g., Bitcoin wallets) and DHT (Distributed Hash Table) cluster nodes. Lightweight clients rely entirely on full nodes for transaction verification, resulting in dependence and vulnerability. DHT cluster nodes share storage; thereby, each node maintains a fraction of the data and retrieves the remaining data from other nodes. This will introduce processing latency when verifying new transactions. Testing conducted on Bitcoin indicates that nodes maintaining recent blocks can locally verify most new transactions. Based on this, this article proposes a new design, RBS (Recent Block Storage), where each cluster node stores recent blocks and shares older ones. Lightweight clients expand storage for recent blocks. Test results on Bitcoin show this design can reduce remote data retrieval and associated processing delays for lightweight nodes by 90 % with only 8 GB of extra storage per node. This design improves the independence and security of lightweight clients and reduces inter-node data retrieval within DHT clusters. It will facilitate the broader application of blockchain technology across various fields.