## 3 State of the Art
### Financial Viability of Selected IoT Communication Technologies
For example, tasks such as hardware and software installation, training and support, device maintenance, disposal, and project management were included. Once the categories and tasks were identified, the next step was to assign cost values to each of them. The costs of a row are always summarized in a yellow field in the right column, and the cost of all lines in a section is displayed in an orange box (c.f. Figure 3). Visually, the calculator is kept in unobtrusive gray, while the headings are highlighted in light blue. In addition, the color of individual fields varies depending on their meaning, ranging from to be filled in, via calculated automatically, to the sum above everything (c.f. Figure 4). To make the tool even more user-friendly, symbols were used to represent the different types of costs. For example, a dollar sign (\(\epsilon\)) was used to indicate procurement costs, a wrench symbol was used to indicate maintenance costs, and a recycle symbol was used to indicate disposal costs (c.f. Figure 5). Figure 3: Design of the “Artifact” cost calculator; Own illustration. In addition to assigning costs to each task, the tool also included units of measurement. This helped users understand the scale of the costs associated with each task. Once all the costs were assigned and the tool was complete, it was tested and validated to ensure its accuracy and usability. The tool was tested using different scenarios to determine its effectiveness in estimating the TCO of IoT devices. Feedback was collected from users to identify any areas of improvement, and the tool was updated accordingly. Due to the different cost structures between IoT devices and gateways, it was necessary to construct separate calculators for each. As such, separate calculations are necessary to accurately estimate the total cost of ownership for each type of device (c.f. Figure 5). Additionally, external project costs may also differ between IoT devices and gateways. For instance, the installation of gateways may require more specialized expertise and equipment, resulting in higher costs. Overall, the \"Pragmatic Computational Tool\" provides a practical and user-friendly way to estimate the life cycle costs of IoT devices. It is easy to use, with well-explained colors, symbols, and units, making it an effective tool for decision-makers in the IoT industry. Figure 4: Color scheme of the “Artifact” cost calculator; Own illustration. Figure 5: Interface of the Artifact for the life cycle cost calculator for LoRaWAN; Own illustration. Validating and Discussing the Scientific Artifact \"Pragmatic Computational Tool\" for Calculating the Life Cycle Costs of IoT Devices in a Smart City Environment  
The evaluation and assessment of an artifact within the framework of design science research necessitate a systematic process, encompassing the establishment of clear evaluation goals, the design of the evaluation methodology, the collection and analysis of relevant data, the interpretation of results, and the reflection on findings to inform iterative improvements [13,14]. The validation of the scientific artifact \"Pragmatic Computational Tool\" for calculating the life cycle costs of IoT devices was conducted using several use cases from different domains, including smart cities, environmental monitoring, energy management, citizen science, and traffic management. The objective of the validation was to assess the accuracy and usability of the tool in various real-world scenarios and to identify any limitations or areas for improvement [31]. The assessment of the \"Pragmatic Computational Tool\" for calculating the life cycle costs of IoT devices was conducted using a validation process that involved several use cases from different domains. Out of the fifteen entities contacted, nine participated in the assessment, representing a diverse range of organizations employing either LoRaWAN or NB-IoT communication technologies in their smart city environments.