# A Systematic Mapping Study on the Modernization of Legacy Systems to Microservice Architecture
## 5 Discussion of Results  
This section will present a comprehensive examination of the results of our investigation. The evidence gathered suggests that the modernization process is of crucial importance for both public and private organizations because it enables them to transition their legacy systems to MSA, an architectural style that enables them to address new business requirements. As previously stated in Section 4.4, the modernization of legacy systems with the implementation of a new architectural style is an industry-wide necessity that hasbeen addressed through collaborative initiatives between academic and industrial partners. Our SMS encompasses 43 studies, selected from a total of 1037 studies through a systematic process comprising several phases. Each study reported an initiative that was targeted at supporting the modernization process, thereby contributing to a more comprehensive analysis for identifying the genuine activities and steps associated with this process type. Next, we address the relevant topics of each RQ established for our investigation. Initiatives. As identified in RQ1 (Figure 2), the initiative type named \"Approach\" was the most common in our SMS. At the same time, the findings of our investigation indicated a lack of clarity regarding the terminology employed to define these initiatives. By analyzing the initiatives, their level of maturity, and their adoption by the industry, it can be surmised that this confusion of concepts presents a significant obstacle for industry professionals to adopt such initiatives in their daily activities, largely due to a lack of comprehension of the activities involved. Although a significant number of studies have been industrial or with industry participation (see Figure 4), this number can be considered below expectations, as the subject of our investigation is directly related to the interest of the software industry. In this sense, the proposed process (see Section 4.6) can serve as a guideline framework for the creation of alternative software modernization processes, since it encompasses a comprehensive set of activities and steps that can be universally applied to any software system. Application domains. Our analysis revealed that 33 of the 43 studies selected for review in our SMS provide concrete evidence and were classified in one of the nine identified domains (see Figure 3). Although these studies were classified as belonging to the Information Systems area, the evidence showed that researchers and practitioners were engaged in efforts to promote initiatives in a range of domains. It can thus be inferred that despite belonging to different domains, the systems in question exhibited common execution problems, including a lack of scalability, high response times, and an inability to meet new market demands. In essence, the systems identified in these studies exhibit a set of common features across nearly all application domains, facilitating information exchange between users and systems to meet user needs. Based on this scenario, it can be posited that the modernization of such systems with the implementation of a more contemporary architectural style enables the mitigation of adverse failures or QoS degradation, thereby preventing any adverse impact on users. The potential consequences of this scenario can be significantly exacerbated, contingent on the criticality of the application in question. To illustrate such adversities, one may consider the scenario in which a lottery system receives a considerable number of requests from its users on the last day of operation. This scenario could result in an overload of processing power, which, in turn, could lead to a significant slowdown or even a disruption of the service/system. Evaluation vs. maturity. The act of conducting some type of evaluation may be used as an indicator of the maturity of the initiatives identified in our investigation.