The Internet of Things (IoT) has provided many services in the fields of intelligent transportation, smart cities, medical treatment, and military. With the development of the IoT, it is expected that 50 billion devices will be connected to the IoT by 2020. Security, privacy, and data storage issues have become key issues in IoT systems. The current centralized architecture model in IoT systems is difficult to scale to meet the needs of future IoT systems.

To solve the above problems, blockchain has become a valuable research area. Blockchain is a distributed database system that can record all information about transactions. It can achieve the required security and reliability in an untrusted environment without relying on central participants. Blockchain will enable IoT devices to send data to the blockchain ledger to prevent tampering and counterfeiting. This fits perfectly into the basic functions and architecture of the IoT. However, blockchain technology is still in its infancy, and its integration with the IoT is still particularly challenging.

This Special Issue aims to bring together researchers and industry professionals to report recent research advances on decentralized and trustable technology in blockchain enabled IoT. In light of the current interest in the integration of IoT and blockchain, this Special Issue welcomes research that discusses central key management, data integrity, privacy protection, IoT platform interoperability, energy transactions. We invite academia and industry to contribute to the latest research advances that help solve the challenges associated with IoT and blockchain integration solutions.

Potential topics include but are not limited to the following:

• Theories of blockchain and distributed systems
• Smart contract and distributed ledger for IoT devices and data
• Blockchain schemes for decentralization in IoT
• Blockchain based security frameworks for IoT
• Anonymity and privacy solutions for blockchain based applications
• Blockchain based identity management and access control systems
• Blockchain for lightweight protocol designs
• Emerging applications of blockchain in Cloud, Edge and Fog computing
• Blockchain in energy management/smart grids
• Distributed blockchain architectures for Software-Defined Networking (SDN) and Network Function Virtualization (NFV)
• A lightweight scalable blockchain framework for IoT
• Security, privacy, and trust of blockchain and distributed ledger technology