## 1 Introduction
Currently, the Arrowhead Framework is unique with its concept and tools for integration of applications between secure localized clouds. The Arrowhead Framework abstracts IoT devices as services in order to enable interoperability between a lot of IoT devices and applications. Further, the Arrowhead Framework provides an improved local cloud compared to global clouds, since it \"glues\" together IoT equipment, realtime data, baseline for data and service security, flexibility to change, and scalability [14]. Using a local cloud, it is easy to decide whether to keep the data originating from the automation solution within the local cloud on the inside of the organization or company or to securely transfer and keep it in another local cloud or global cloud solution. Thus, to sum up the cloud platforms, there are an increasing number of multi-usable cloud service platforms. However, most of these do not have an efficient way, in terms of effort and costs, to integrate and subsequently operate a large number of IoT-devices from various manufacturers for many years. As service-oriented business processes start to appear, [PERSON] [15] posits that, for architecture and infrastructure where standardized processes for accessing data are included, the platform on which the data are stored is unimportant. The key is to apply a standard set of transformations to the various sources of data and thereafter facilitate solutions to access the data via open standards service requests, and thus access data regardless of the solution manufacturer. A problem concerning data sources is that many IoT devices, for instance, do not comply with standards and therefore require a means to be securely and efficiently integrated. Usually, the most significant benefits from using the SOA concept are the reuse of technology and agility to change [16]. Here, the reuse of business processes is more significant than the reuse of technology, as SOA determines the same business activities and puts them in a group as a service. Hence, SOA will decrease the application duplication by reducing process replication. In addition, the use of microservices enables, by using small independent inter-connected services instead of complex monoliths, a number of sustainable benefits which have been found in general IT and cloud contexts: increased re-use of code, lowered complexity; considerably faster agile development and testing cycles due to less dependencies code-wise; continuous automatized and integrated development, testing, deployment, operations and maintenance (i.e., DevOps or DevSecOps), and less support required as a consequence of fewer bugs [17; 18]. The use of platforms and cloud computing renders many interesting technological and economic advantages. However, some end users, such as manufacturing and process industries, hesitate to move their IT/OT infrastructures partly or completely to the cloud. [PERSON] and [PERSON] [19] posit that one of the large concerns is cloud security and the threat of non-transparency and cyberattacks. The non-transparency often originates from the fact that many of the large cloud service providers do not allow their customers to inspect what is in the data centers. [PERSON] et al. (2018) add that it is still not obvious how the technical security issues and the trust issues can be resolved. These issues must be figured out, together with, for instance, the legal requirements imposed by the EU (General Data Protection Regulation, GDPR, and Schrems II), the USA and all countries with non-homogeneous data laws, and by any organization or company that wishes to use cloud services where sensitive information is stored, processed or communicated in between countries. Pertaining to improvements from using IoT or cloud service platforms, related to automation solution development and operation, [PERSON] et al. (2018) present results which indicate that even inexperienced developers are able to craft solutions in the cloud in a significantly shorter time. Further, [PERSON] et al.