Consortium decentralized systems, also known as consortium systems, enable consensus and availability among limited untrusted participants. Given the growing necessity for inter-organizational data sharing, consortium systems have gained significant prominence in cross-enterprise collaboration. File systems, which play a fundamental role in data sharing, face new challenges within consortium systems. The consortium system involves characteristics of both decentralized and centralized systems. The first requirement is decentralization. The system’s functionality, availability, and security must not depend on any individual node. The second requirement is characteristic-awareness, which necessitates optimal data placement across nodes based on policy constraints, performance requirements, and security considerations. The third requirement is high performance and flexible access control. Neither centralized nor existing decentralized file systems can satisfy all three requirements.

This paper presents DeFS, a novel decentralized file system designed for consortium systems. DeFS implements a two-layer architecture that incorporates public nodes into the consortium system, thereby enhancing decentralization. Additionally, we propose a Multi-Ring Distributed Hash Table (MR-DHT) protocol to facilitate characteristic-aware data block distribution. To optimize data routing efficiency, we introduce the Location Cache (L-Cache) mechanism. We have implemented a DeFS prototype and conducted comprehensive performance evaluations across three distinct network configurations, with the largest one having over 1,500 nodes. Results show that DeFS successfully achieves characteristic-aware data placement while delivering \emph{\textbf{10.32X}} lower latency compared to IPFS on average.