ALTOCUMULUS: Enabling Efficient Erasure Coding in IPFS

Erasure coding (EC) is a well-known redundancy technique used to prevent data loss in distributed systems. They typically reduce storage overhead significantly compared to replication. However, they are more complex to use than replication in terms of both deployment and data repair in the event of node failure, particularly in the context of decentralized distributed systems. In this paper, we introduce ALTOCUMULUS, an erasure-coded storage system that efficiently and effectively integrates Reed-Solomon codes on top of the InterPlanetary File System (IPFS). ALTOCUMULUS implements efficient parallel data writing and dynamic data retrieval that adapts its chunk selection according to nodes' performance at runtime. It also provides optimized data repair by enabling nodes to perform repair tasks evenly in parallel. Evaluation results show that ALTOCUMULUS significantly improves write performance compared to replication and alternative EC implementations in IPFS, reaching 89.7% and 92.9%, respectively. In addition, ALTOCUMULUS achieves comparable performance to replication for reads and data repair, while outperforming it in heterogeneous environments and when repairing large datasets.