# Information Security Applications in Smart Cities: A Bibliometric Analysis of Emerging Research
## 5 Discussion
### Addressing the Research Questions  
The literature review developed had three research questions as its core, as presented in the methodological section. Based on literary findings, directions on these questions will now be presented. RQ1--What are the patterns of information security applications found in research on smart cities? This question can be addressed with the six clusters presented in Table 2, separating each cluster according to the main application domain areas, as follows:  
1. Smart Grids and Power Supply: this cluster covers works that mention applications that can cover information and cybersecurity on smart grids as a component of smart city systems to ensure efficient, safe, and sustainable power supply for citizens [226]. Smart grids cover topics such as bulk generation, transmission, distribution, customers, markets, service providers, and operations [78]. 2. Authentication as a security mechanism: this cluster covers applications regarding the control access policies and strategies for data protection in smart city systems, especially considering the large data volumes that are inherent to these systems [291]. Authentication mechanisms are projected to ensure privacy, trust, and reliability in the information and communication flows [51] to protect against invasion by attackers masquerading as legitimate users of the system [85]. 3. Cyberattack prevention/detection in smart cities: this cluster focuses on strategies to prevent or detect cyberattacks or vulnerabilities that may facilitate these attacks in the smart cities context, observing the best practices and methods to be applied in protecting involved systems [280]. The lack of these strategies can cause, for instance, theft of a user's sensitive data, utility fraud, and grid instability [1]. In other words, this can be considered a cluster containing works presenting core concepts and tools that are transversal to all other clusters. 4. Security platforms for smart cities: this cluster involves not only technological platforms but the whole organizational and business instances needed to promote security to smart cities-related services and systems [60]. The main idea is to deliver quality of life for the users of these services and systems, which are any citizen in a smart city area [302]. Quick and efficient managerial decision-making is the main concept to ensure security platforms operate successfully in preventing risks from becoming events negatively affecting smart city services delivery for citizens [302]. These platforms are a means for aggregating concepts of the other five clusters, as can be understood by the diagram in Figure 6 in the answer for RQ2, synthesizing the relationships between all clusters of applications. 5. Evaluation of threats to cybersecurity: this cluster deals with ways to evaluate threats to the smart cities systems, facilitating, for example, the design and management of security platforms and ensuring the necessary indicators and related analysis to promote the detection and prevention of cyberattacks [311; 319]. It covers from devices to threat evaluation techniques, which can be used in support of security measures planning [6; 54]. 6. Cybersecurity and society: this is the most comprehensive cluster, involving all the elements needed to promote cybersecurity for society, considering smart cities as cyberphysical systems [328]. It covers legal and ethical concepts, passing by managerial strategies and reaching the technical level with the frameworks of techniques/tools to ensure cybersecurity for people [333]. Figure 6: Relationships between the concepts involved in the applications clusters. RQ2--What are the most demanding areas for information security in smart cities studies? To answer this question, Figure 6 was created seeking to highlight the dynamics between the previously observed clusters. It should be noted that the diagram in the figure does not present a composition of works/authors found in the literature as in Figure 3, but the conceptual alignment and flow between the clusters.