Empowering Light Nodes in Blockchains with Block Summarization

Blockchains have revolutionized the storage of data in an immutable, transparent and non-centralized way. However, public blockchain systems like the Bitcoin system face a problem of scalability, primarily due to the significant and growing size of its blockchain. This paper introduces a method, termed block summarization, which reduces blockchain storage overhead for systems having transferable transactions. The proposed method allows resource-restricted light nodes to store a form of the blockchain such that it can validate the transactions independently which ultimately reduce dependency on full nodes. This way, we can achieve a middle ground between Simplified Payment Verification (SPV) nodes which can only verify the membership of a transaction in the blockchain, and full nodes with pruning enabled which can only support pruning provided they have an infrastructure of full nodes. We implemented our algorithm for a custom blockchain using Bitcoin blocks and were able to achieve a compression ratio of 0.54.