# Emerging Industrial Internet of Things Open-Source Platforms and Applications in Diverse Sectors
## 2 Background
### Emerging Trends in IIoT Architectures  
In recent years, the IIoT has seen a significant transformation, with a strong emphasis on creating and applying practical designs known as service-oriented architectures. These architectural solutions aim to construct and deploy IoT infrastructures in industrial settings in a highly effective manner, with the potential to enhance efficiency, productivity,and safety across several industries. Various recommendations and frameworks have emerged, elaborating on the principles of service-oriented architectures in the IIoT field. Two notable instances of these are the IIRA and stratified IoT architectures. These frameworks provide structured guidelines and implementation of IIoT systems. An essential aspect of this phenomenon is the widespread utilization of open-source software and hardware, together with platforms, to fully leverage the potential of IIoT systems.  
To improve readers' understanding of this emerging trend, we recognize the following recent publications that extensively examine the complexity of IIoT designs. The initial study focused on the creation of a system that gathers and oversees data from PEM hydrogen producers utilizing the IIoT [14]. This research conducted a comprehensive analysis of data collection and monitoring systems specifically developed for PEM hydrogen generators, which have a vital function in various industrial operations. Users can retrieve this up-to-the-minute data via a web-based interface made possible through an IIoT framework [14]. The impetus for this study stemmed from the necessity of monitoring the production of hydrogen in a photovoltaic (PV)-powered microgrid, in line with the notion of \"green hydrogen\" generated from renewable energy sources. The paper's contributions encompass real-time monitoring, configuration adaptability, online remote access, the effective implementation of IIoT technologies, and validation through empirical findings. This work satisfies a research need in the field of hydrogen generation by developing and monitoring DAQ systems. It specifically focuses on an IIoT-based approach, which adds value to the existing literature on this issue [14].  
The second work discusses the difficulties and technology involved in IIoT designs (SOA2). This work provides significant insights into the primary challenges and emerging technologies in IIoT architectures. It provides a thorough and inclusive evaluation of the topic. The introduction provides an overview of the shift from the IoT to the IIoT, highlighting the IIoT's significance in improving operational efficiency and integrating Information Technology (IT) and Operational Technology (OT). Furthermore, it emphasizes the importance of Industry 4.0 and Cyber-Physical Systems (CPSs) within the framework of the fourth industrial revolution. The process of converting industrial processes into a digital form poses novel difficulties for the complete integration of IIoT systems. In order to tackle these difficulties, the study examines and contrasts three extensively acknowledged IIoT reference architectures: RAMI 4.0 [15] and IIRA [16]. Reference architectures serve as a guide for building IIoT systems, facilitating the incorporation of sensors into enterprise management functionalities [17].