IoT Passport: A Blockchain-Based Trust Framework for Collaborative Internet-of-Things.

Internet-of-Things (IoT) is a rapidly-growing transformative expansion of the Internet with increasing influence on our daily life. Since the number of "things" is expected to soon surpass human population, control and automation of IoT devices has received considerable attention from academia and industry. Cross-platform collaboration is highly desirable for better user experience due to fragmentation of user needs and vendor products with time. Centralized approaches have been used to build federated trust among platforms and devices, but limit diversity and scalability. We propose a decentralized trust framework, called IoT Passport, for cross-platform collaborations using blockchain technology. IoT Passport is motivated by the familiar use of passports for international travel but with greater dynamism. It enables platforms to establish arbitrary trust relations with each other containing specific rules for intended collaborations, enforced by a combination of smart contracts. Each interaction among devices is signed by the participants and recorded on the blockchain. The records are utilized as attributes for authorization and as proofs of incentive plans. This approach incorporates the preferences of participating platforms and end users, and opens new avenues for collaborative edge computing as well as research on blockchain-based access control mechanism for IoT environments.