A Novel Scheme to Improve the Scalability of Bitcoin Combining IPFS With Block Compression

Abstract

As of the end of September 2021, the size of the Bitcoin blockchain has reached 366.9GB and continues to increase at an average annual growth rate of 17.6%. The large-scale demand for storage space constrains new nodes from joining the network, which seriously hinders the development of blockchain technology. In this paper, to explore the data characteristics of the Bitcoin blockchain, we performed a comprehensive statistical experiment on the current 680,000 blocks. The analysis results indicated that in nearly 95% of blocks, the number of spent transaction output (STXO) accounts for more than 67% of the total transaction outputs. Inspired by this feature, we proposed a novel storage scheme to reduce the size of blocks by deleting the transaction data with the STXO ratio over 67% first and compressing fixed-length fields of those transactions. Then, the newly generated block files were deposited to the InterPlanetary File System (IPFS) private network to improve the scalability of the Bitcoin blockchain. The experiments and evalutions showed that the proposed scheme achieved a compression ratio of 96.9% and saved 330GB of storage space for the Bitcoin full nodes while guaranteeing the normal operation of the Bitcoin network.