# Low-Cost Digitalization Solution through Scalable IIoT Prototypes
## 3 Materials and Methods
### Software  
The second part of the solution is the software. Software solutions can be divided into firmware and cloud application software. Various possibilities exist on the market for both elements of the software part of the solution. The selected software must enable a quick improve-control cycle so that the actions aimed at the process improvement can be tested quickly, and the corresponding data collected and visualized. A similar set of requirements to the ones used for the hardware part also apply to the software part of the solution. * Cost effectiveness--While most of the firmware solutions are open-source or available with the purchase of the hardware part, some are acquired separately. The cloud application software and device management is the element that needs to be purchased separately, and the possibilities are numerous. * Implementation simplicity--Having in mind various elements of the solution and differing levels of developer's expertise, the solution benefits greatly if the technologies used are the ones that are popular in the developer community. * Scalability--The firmware should provide a modular structure so that it is easy to expand and to add new functionalities. Both the firmware and cloud application software should provide this, and the technology used for development can provide greater flexibility. * Development speed--Technologies that are already tested and integrated with the hardware part of the solution would provide an easier and quicker setup phase. The popularity and simplicity of the chosen technology are considered when the solution is selected. * Security--The development of both software elements should provide the necessary security elements. The cloud application is more vulnerable than the firmware ele  
Figure 1: Industry 4.0 adoption process with the specific machine digitization flow. ment. Also worth noting is that most cloud IoT platforms take particular measures in ensuring the safety and security of customers' data. Several solutions are considered with regard to the requirements set in Section 1 and the two previous subsections, as well as the state of the art (Section 2):  
The first solution concept considered is the industry automation standard; a ready-made industrial-grade IIoT solution with a high level of robustness, safety, and reliability. It offers wireless connections and proprietary software that easily connect and interface the machine with an already existing connection. These solutions are not as easily obtained, and often require specific training with regard to software. These solutions are provided by Siemens, ABB, Bosch, etc. The drawback of this solution is that they are expensive and the implementation is not as quick as the other solutions. With the involvement of the big automation companies, the fear of a vendor \"lock-in\" is a well-known phenomenon [59; 60] that is perceived to be even more critical in the case of SMEs. This is an even bigger issue when the high cost of implementation is considered. The second solution concept is a low-end prototyping solution. These solutions are very cheap and the devices are readily available in the market. A typical example is Arduino boards, microcontroller-based boards that offer very high customization possibilities. Having in mind the lack of processing power and the limited connectivity abilities of these boards, they would need to be paired with a more powerful board such as Raspberry Pi. However, the solutions need to be heavily adapted for them to scale up to the fully matured solution. The industrial setting demands a certain level of safety features that these boards do not provide as-is. The authors have chosen the conceptual solution that provides industrial-grade equipment and can be used for a relatively inexpensive development of the prototype. The real value of these solutions lies in the possibility to use the same equipment in the final implementation after digitalization to the scope of the entire factory.