Distributed common data environment using blockchain and Interplanetary File System for secure BIM-based collaborative design

Existing platforms for collaborative BIM design have a centralized system architecture, which suffers cybersecurity risks of design data manipulation and denial of access, leading to a loss of data traceability, a decline in design productivity, and project delays. Blockchain is a promising technology to solve such risks by providing decentralized and immutable data storage. However, integrating blockchain with BIM faces a problem that blockchain is inherently unsuitable for storing large-sized design files like BIM models, hindering blockchain from protecting BIM data integrity. Therefore, this paper proposes a distributed common data environment (DCDE) framework for BIM-based design leveraging two distributed technologies: blockchain and Interplanetary File System (IPFS). The DCDE framework guarantees irreversible design changes storage using blockchain while secures design file storage using IPFS. A blockchain transaction data model and a smart contract are also developed within the framework to support DCDE functionalities. Lastly, framework applicability and performance are tested in an illustrative design example. Results show that: (1) DCDE is a feasible solution for secure design collaboration, and (2) DCDE latency (in millisecond-level), TPS (60 transactions per second), and storage cost (12.5 KB per day) are within an acceptable range.