# Mobile Network Operators' Assessment Based on Drive-Test Campaign in Urban Area for iPerf Scenario
## 5 Discussion  
### Synthesis of Results  
The basic QoS measures used in the assessment of mobile networks are throughput and latency [1]. In the iPerf scenario, we mainly analyzed throughput for TCP and UDP, and additionally jitter for UDP. These parameters are strongly correlated with lost or received datagram rates (i.e., LDR or RDR). Considering the specificity of both analyzed protocols, UDP is usually used for network stress testing and the assessment of the maximum throughput or capacity [26; 31; 32]. In the context of iPerf tests, it is worth emphasizing that throughputs obtained for TCP and UDP should not be directly compared. This is due to the main advantages and considerations of each protocol, as are shown in Table 4[43].  
In the iPerf scenario, we had no way to evaluate latency. Therefore, we use the global assessment presented by Systemics-PAB in terms of the four implemented measurement scenarios mentioned in Section 2.1. Based on them, three QoS metrics, so-called main KPIs for Internet access, i.e., average DL and UL throughput and latency, were determined, which are depicted in Figure 20[33]. With regard to the comparison of four Polish MNOs, the obtained results coincide with the conclusions received by Systemics-PAB: throughput for Plus is the highest and lowest for DL and UL, respectively, and Orange and T-Mobile have practical the same KPI values.  
\begin{table}
\begin{tabular}{l c c c} \hline \hline
**Property** & **UDP** & **HTTP/TCP** & **FTP/TCP** \\ \hline Focus on unidirectional traffic without & & Yes & No & No \\ dependencies on return channel & & Yes & No & No \\ Uplink throughput is measured on receiving side, & & Yes & No & No \\ i.e., as the true network throughput & & Yes & Yes & No \\ Sustainable capacity required as result & & Yes & Yes & No \\ Intermediate throughput is measured on IP-level & & Yes & Yes & No \\ Applicable for the Network Performance Score & No & Yes & No \\ \hline \hline \end{tabular}
\end{table}
Table 4: Main considerations and advantages of UDP and TCP [43].  
Figure 20: Main KPIs for Internet access for four Polish MNOs based on drive test campaign (based on [33]).  
When analyzing PCCs averaged for all MNOs (see Figures 4a and 5a), we noticed some discrepancy associated with the RSRQ-5G metric in relation to the PCC for individual MNOs. Well, the RSRQ-5G-associated correlations are usually much lower for all than for the selected MNO. This could indicate that the analyzed data set (in the XY plane, where RSRQ-5G is one of the parameters) for each MNO is clustered and the complete data set for all MNOs is characterized by high dispersion. Therefore, we hypothesized that RSRQ-5G can be used to classify/identify MNOs based on measurements. Considering that RSRQ-5G is strongly correlated with SINR-5G (i.e., \(0.64<PCC<0.79\)) for all analyzed cases (i.e., all MNOs, TCP and UDP, and UL and DL), we present the measurement data and regression lines in Figures 21-24 for TCP and UDP, respectively.  
Based on the obtained regression curves (see Figures 22 and 24), we can notice that the lines do not overlap, thus allowing for the identification or classification of MNOs based on averaged measurement data, as well as the assessment of their QoS (i.e., KPIs). For the selected SINR-5G, we can rank MNOs, i.e., Play, T-Mobile, Orange, and Plus, by the increasing RSRQ-5G. In this way, the obtained assessment of MNOs based on the reference signal quality coincides with the assessment of MNOs in terms of KPIs analyzed by Systemics-PAB (see Figure 20).