# Privacy and Security in Cognitive Cities: A Systematic Review
## 3 Results
### Security and Privacy Challenges  
In the literature about cognitive cities, privacy and information security are mainly regarded as important challenges that need to be addressed. For organizational purposes, we classified the challenges discussed in each article into technical, societal, or regulatory. Table 6 summarizes the main focus over privacy and security on each article. Technical challenges mainly refer to: \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Article**} & \multicolumn{4}{c}{**Main Focus**} \\ \cline{2-5}  & **Technical** & **Social** & **Regulatory** \\ \hline [PERSON] and [PERSON] [57] (2019) & ✓ & & & \\ [PERSON] and [PERSON] [54] (2011) & ✓ & & & \\ [PERSON] and [PERSON] [49] (2016) & ✓ & ✓ & & \\ [PERSON] et al. [47] (2018) & ✓ & & & \\ [PERSON] et al. [58] (2019) & ✓ & ✓ & & \\ [PERSON] et al. [51] (2015) & ✓ & ✓ & & \\ [PERSON] et al. [53] (2015) & ✓ & & & \\ [PERSON] et al. [56] (2016) & ✓ & ✓ & & \\ [PERSON] and Solanas [5] (2018) & ✓ & & & \\ [PERSON] and [PERSON] [6] (2019) & ✓ & & & \\ [PERSON] and [PERSON] [46] (2019) & ✓ & & & \\ [PERSON] and [PERSON] [50] (2018) & ✓ & & & \\ [PERSON] [48] (2015) & & & ✓ & ✓ \\ [PERSON] et al. [41] (2011) & & & ✓ & \\ [PERSON] and Uffer [52] (2016) & & & & ✓ \\ [PERSON] et al. [55] (2013) & ✓ & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Articles and their main focus. \begin{table}
\begin{tabular}{c c c c c} \hline \hline
**Stage** & **R1–R3** & **R1–R4** & **R2–R3** & **R2–R4** \\ \hline First search & \(0.65\pm 0.35\) & \(0.88\pm 0.12\) & \(1.00\pm 0\) & \(0.65\pm 0.35\) \\ Backward search & \(1.00\pm 0\) & \(1.00\pm 0\) & \(0.66\pm 0.34\) & \(1.00\pm 0\) \\ Forward search & \(1.00\pm 0\) & \(1.00\pm 0\) & \(1.00\pm 0\) & \(1.00\pm 0\) \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Inter-rater reliability: \(\kappa\) values in every stage for each pair of reviewers sharing publications (95% confidence interval). \begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Reference** & **QA1** & **QA2** & **QA3** & **QA4** & **Result** \\ \hline [PERSON] and [PERSON] [5] (2018) & 1 & 1 & 1 & 1 & 1 \\ [PERSON] [48] (2015) & 1 & 1 & 1 & 1 & 1 \\ [PERSON] et al. [60] (2015) & 0 & 0 & 0 & 0 & 0 \\ [PERSON] et al. [55] (2013) & 1 & 1 & 1 & 1 & 1 \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Selected articles and quality assessment result. * Preserving citizen's privacy from disclosure attacks [6; 47; 50; 51; 53; 56], and privacy preservation for ML algorithms [57]. * IoT-related privacy issues: privacy requirements partially covered [47], and that deleted online information can be recovered by experts [47]. * Data integrity and quality issues: the use of truthful information for analytics and governing policies [46; 48; 49], protections from false data injection for ML algorithms [6; 50; 57], the difficulties of data quality testing caused by the variety and volume of data and data sources [48], and data quality and bias concerns resulting from removing context from data [49]. * IoT-related security issues: unattended components, low computing and energy resources make IoT devices vulnerable to attacks [47; 57], and security problems of IoT-supporting technologies [47]. * The need for measuring and verifying the security of alternative systems architectures [54]. * Data misuse caused by the lack of transparency and accountability of UC [49]. * Balance issues: coexistence of cognition with security and privacy [55], and the conflicting goal of enhancing accessibility to resources, security, and empowerment of citizens at the same time [46]. * And willingness to share also seen as a technical challenge [56; 58]. Societal challenges are mainly oriented to:
* The willingness of citizens to actively share their information [4; 51; 56; 57; 58; 49].