*Article* **SASLedger: A Secured, Accelerated Scalable Storage Solution for Distributed Ledger Systems**

**Haoli Sun 1,\*, Bingfeng Pi 1, Jun Sun 2, Takeshi Miyamae 3 and Masanobu Morinaga 3**


**Abstract:** Blockchain technology provides a "tamper-proof distributed ledger" for its users. Typically, to ensure the integrity and immutability of the transaction data, each node in a blockchain network retains a full copy of the ledger; however, this characteristic imposes an increasing storage burden upon each node with the accumulation of data. In this paper, an off-chain solution is introduced to relieve the storage burden of blockchain nodes while ensuring the integrity of the off-chain data. In our solution, an off-chain remote DB server stores the fully replicated data while the nodes only store the commitments of the data to verify whether the off-chain data are tampered with. To minimize the influence on performance, the nodes will store data locally at first and transfer it to the remote DB server when otherwise idle. Our solution also supports accessing all historical data for newly joined nodes through a snapshot mechanism. The solution is implemented based on the Hyperledger Fabric (HLF). Experiments show that our solution reduces the block data for blockchain nodes by 93.3% compared to the original HLF and that our advanced solution enhances the TPS by 9.6% compared to our primary solution.

**Keywords:** blockchain; scalability; storage; data integrity; performance
