# A Novel Approach to Multi-Provider Network Slice Selector for 5G and Future Communication Systems
## 6 Experimental Evaluation
### Results and Discussion  
To understand the results measured by each approach, we observed the behavior of the criteria in the flows of networks. To this end, we used the boxplot statistical resource to evaluate the main QoS criteria, such as the symmetry of the data, its dispersion, and the possible presence of outliers. In addition, we used the histograms feature to verify the distribution of the other criteria considered. Note that Figure 7 presents several outliers for the jitter and loss criteria. This is characterized by their stochastic, dynamic, and nonlinear behavior and the variation in traffic rates considered in Table 2.  
After this preliminary analysis of the behavior of the criteria adopted as input parameters of the implemented framework, we evaluated the four approaches concerning their capability of classifying the best slice, considering the weights or preferences defined a priori by the _Decision Maker_, and also the traffic requirements of the UEs. Tables 5-8 detail the results for each method used in the NSSF service. \begin{table}
\begin{tabular}{c c} \hline
**Test** & **Weights**\({}^{1}\) \\ \hline
1 & [0.3 0.2 0.1 0.09 0.03 0.03 0.25] \\
2 & [0.3 0.4 0.15 0.05 0.05 0.02 0.03] \\
3 & [0.1 0.05 0.15 0.3 0.3 0.08 0.02] \\
4 & [0.136, 0.144, 0.144, 0.144, 0.144, 0.144, 0.144] \\
5 & [0.144, 0.236, 0.04, 0.334, 0.165, 0.078, 0.003] \\ \hline \end{tabular} \({}^{1}\)[“Latency”, “Jitter”, “Loss”, “Bandwidth”, “Transfer”, “Distance”, “Reliability”].  
\end{table} 
Table 4: Weights Setup. \begin{table}
\begin{tabular}{c c c c} \hline
**Test** & **Slice 1 (\%)** & **Slice 2 (\%)** & **Slice 3 (\%)** \\ \hline
1 & 68.4 & 4.4 & 27.2 \\
2 & 17.2 & 68.0 & 14.8 \\
3 & 78.4 & 21.6 & 0.0 \\
4 & 93.2 & 6.4 & 0.4 \\
5 & 100.0 & 0.0 & 0.0 \\ \hline \end{tabular}
\end{table} 
Table 5: VIKOR Method Results. Considering the results generated using the VIKOR method, as detailed in Table 5 and illustrated in Figure 12, Slice 1 (Remote Driving) was selected as the best in four of the five tests performed. For the variation of weights of Test 3, Slice 1 was selected in 78.4% of the iterations and in Test 4 it was selected 93.2% of the time. This behavior emphasizes the sensitivity of the Latency and Reliability criteria since these two parameters are critical for the Remote Driving service. The results from the COPRAS method are described in Table 6 and shown in Figure 13. Slice 3 (ITS) was selected as the best in four of the five tests performed, followed by Slice 1 \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test** & **Slice 1 (\%)** & **Slice 2 (\%)** & **Slice 3 (\%)** \\ \hline
1 & 6.0 & 33.6 & 60.4 \\
2 & 14.0 & 25.6 & 60.4 \\
3 & 0.0 & 1.6 & 98.4 \\
4 & 1.2 & 10.4 & 88.4 \\
5 & 100.0 & 0.0 & 0.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: COPRAS Method Results. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Test** & **Slice 1 (\%)** & **Slice 2 (\%)** & **Slice 3 (\%)** \\ \hline
1 & 10.8 & 64.8 & 24.4 \\
2 & 47.2 & 9.2 & 43.6 \\
3 & 0.0 & 0.8 & 99.2 \\
4 & 4.8 & 18.4 & 76.8 \\
5 & 100.0 & 0.0 & 0.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 7: TOPSIS Method Results. Figure 12: VIKOR Method. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Test** & **Slice 1 (\%)** & **Slice 2 (\%)** & **Slice 3 (\%)** \\ \hline
1 & 14.4 & 52.4 & 33.2 \\
2 & 19.2 & 24.0 & 56.8 \\
3 & 0.0 & 0.4 & 99.6 \\
4 & 9.2 & 20.0 & 70.8 \\
5 & 0.8 & 1.2 & 98.0 \\ \hline \hline \end{tabular}
\end{table} 
Table 8: PrometheII Method Results. (Remote Driving) in Test 5. Note that for Test 3, Slice 3 was chosen in 98.4% of the iterations. In the VIKOR method, Slice 1 had a higher selection ratio, followed by Slice 2. This behavior also occurs in Test 3 from the TOPSIS and Promethee II method. Slice 3 was selected at rates of 99.2% and 99.6%, respectively. This characteristic demonstrates the greater flexibility in the classification of alternatives for these methods as a function of the weights adopted.