In addition to functionalities, business process management (BPM) involves several key indicators such as openness, security, flexibility, and scalability. Optimizing system performance is becoming a great challenge for an ever-increasing large-scale distributed application system in the digital economy on the Internet of Things (IoT) era. In a centralized BPM, many indicators, such as security and openness, or cost and flexibility, are conflicting with each other. For example, inviting new partners across enterprises, domains, and regions to form a service workflow exposes new risks and needs additional security mechanisms for scrutiny; enhancing the flexibility of business workflow compositions increases the cost of security assurance. Blockchain technology (BCT) has thrown the light on the development of vital solutions to various BPM problems. BCT has to be integrated with other BPM system components that often involve IoT devices to implement specified functionalities related to the application. Currently, the potentials of using BCT have been explored although still at an early stage. In this paper, the states of the art are presented to identify emerging research topics, challenges, and promising applications in integrating BCT into the development of BPM.

Internet of Things (IoT) refers to networks with billions of physical devices for collecting, sharing and utilizing data in the virtual world. Most of IoT applications centralize security assurance in creating, authenticating, transferring, or delating system components. However, the centralization exposes its limitations to meet security needs of a rapidly-growing number of things world-widely. How to scale up the applications with assured security becomes a critical challenge. Blockchain Technology (BCT) is a promising solution to provide security and protect privacy in a large scale; especially, smart contracts offer opportunities to improve the reliability of IoT applications. Smart contracts establish trusts for both of data and executed processes. Recently, many literature surveys and positioning articles have been published on the integration of BCT with IoT, but they are limited to superficial discussions of technical potentials, and very few of them have a thorough exploration of the challenges in developing BCT for IoT at technical levels. This paper uses the system design approach to scrutinize the state of the art of study on BCT-based applications and clarify critical research areas of enabling BCT for security assurance: (i) the relations of BCT and IoT are modelled and discussed; (ii) the needs of eliminating threats in IoTbased applications are defined as functional requirements (FRs), existing works on enabling technologies of BCT are defined as the physical solutions (PSs); (iii) the mappings between FRs and PSs are established to identify the limitations and the critical areas for the applications of BCT in large-scale distributed environment.

Innovating business processes involves cutting-edge technologies where the Internet of Things (IoT) and Blockchain are technological breakthroughs. IoT is envisioned as a global network infrastructure consisting of numerous connected devices over the Internet. Many attempts have been made to improve and adapt business workflows for best utilizing IoT services. One possible solution is to digitize and automate internal processes using IoT services, in which Blockchain smart contract is a viable solution to establish the trust of process executions without intermediaries. Modern business processes are composed of disparate services; many of them tend to be delivered based on IoT. Interoperating with such services poses major challenges: 1) time for finality settlement of transactions is unpredictable and usually experiencing delay; 2) several implementations of permissioned Blockchain pose a major concern of trust regarding nodes that perform consensus; and 3) trust of process executions and IoT information is the major factor to the success of modern business processes, which require the composition of distributed IoT services. Traditional business processes are mostly managed by a single entity, which induces the problem of trust of process executions. In this paper, a smart contract for establishing the trust of process executions that fits into the IoT environment is presented. A consensus approach with selected validators extended from Practical Byzantine Fault Tolerance (PBFT) is introduced to address time and prejudice challenges.