Recently, Blockchain and Cloud of Things (CoT) enabled by the fusion of cloud computing and internet of things have gained prevalent attention due to their tremendous and highly valuable services in modern technical applications. Blockchain provides groundbreaking solutions for confronting network security, data privacy and decentralization challenges in CoT whereas CoT provides scalability and fault tolerance functionalities for strengthening the adeptness of blockchain functions. As both the blockchain and CoT technologies are interdependent, their fusion termed as BCoT serves as a highly promising empowerer for a vast array of use-cases. Therefore, this paper presents an intensive survey of BCoT. It explains the motivation behind blockchain CoT integration. The paper elucidates the scope of collaborating blockchain with CoT and its potential gains. It reviews BCoT applications in heterogeneous use-case domains. This article presents various merits of blockchain CoT integration. It then identifies and describes the critical research barriers and open problems along with prominent solutions. Lastly, this survey provides significant further directions for promoting research studies in this field.

Blockchain, BCoT integration, Cloud of Things, Commercial applications