## 2 Related Work  
When designing the exchange of messages between systems, it is important to be able to model integration flows in a unified manner. Modeling of software and IT systems architecture is commonly done using UML [7]. The language itself does not provide mechanisms for modeling messaging patterns. However, stereotypes as extensibility mechanisms of the UML can be applied to provide new semantics for patterns [13]. Stereotypes are grouped into logically consistent sets called profiles. Generally, constructing UML profiles is a simple and flexible way to provide semantically new modeling elements for use in various fields. The Internet of Things allows for acquiring real-time data from multiple spatially distributed devices. In that field, [PERSON] and [PERSON] [14] showed a UML profile that supports the transformation of interfaces in the IoT environment to representational state transfer (REST) type ones. In addition, [PERSON] et al. [15] introduced a profile with concepts related to real-time databases and integrated with the Object Constraint Language (OCL) to enforce the variation points consistency. The STS4 IoT UML profile was introduced by [PERSON] et al. [16]. The profile simplifies the definition of IoT applications and their integration into other information systems, such as stream data warehouses. Moreover, digital twin bridges the physical and virtual spaces. [PERSON] et al. [17] proposed a profile that uses Systems Modeling Language (SysML) stereotypes to represent the system design of a digital twin in a unified manner. The profile includes system design digital models for the following layers: virtual space, system services, relationships, and digital twin data. SysML itself is defined as an extension of a subset of the Unified Modeling Language using a profile mechanism. Furthermore, OPC unified architecture (UA) is a platform-independent standard for message-based communication between clients and servers on various types of networks used to facilitate information exchange. OPC UA has been adopted in various domains, such as power grids, building automation, and smart devices, to support the interoperability of involved systems. These domains also use the Unified Modeling Language as the standard notation for data or system modeling. The use of various notations in the same domain causes compatibility issues. [PERSON] et al. [18] addressed this issue by presenting an approach for transforming OPC UA to UML to improve their compatibility and integration. In the approach, the authors rigorously analyzed the semantics of OPC UA elements and established a mapping between OPC UA and UML modeling means. The converse approach was proposed by [PERSON] et al. [19]. They proposed an automatic transformation from UML class diagrams to OPC UA information models by extending UML to guarantee the transformation preserves all relevant information. Analyzing the current literature on the subject, it can be seen that UML profiles are used in many areas. However, there is no up-to-date profile for modeling integration flows. The design of integration flows requires more than just stereotypes. A recent review by [PERSON] and [PERSON] [20] showed the evolution of software development methods. They emphasized that in parallel significant advancements occurred in the field of the software architecture description and pointed out the _1+5_ architectural views model [12]. Indeed, recently published research papers show a trend of applying a broader architectural perspective to the design of diverse IT systems. The communication aspect gains importance also in blockchain applications. For example, [PERSON] et al. [21] present the deployment view of their solution and use UML deployment diagrams. Although they have not formally constructed a new profile, they have proposed specific stereotypes for IoT, Software Guard Extensions (SGX), and blockchain nodes, services, and protocols, e.g.