# User QoS-Based Optimized Handover Algorithm for Wireless Networks
## 4 Experimental Results
### Performance Analysis
In Scenario 1, considering the time when the UE is connected to a specific AP, the experimental results show that using the built-in handover algorithm of Mininet-WiFi stabilized the connection with a specific AP, resulting in 17 handovers (see Figure 6a). However, using DoTHa's handover algorithm generated a large number of handover situations, resulting in 248 handovers (see Figure 6b). This result shows that this method can cause connection instability problems. The handover algorithms using OHA and OHAQR also provided a stable connection with a specific AP, resulting in 13 and 15 handovers, respectively (see Figure 6c,d). Throughput is the rate at which a UE successfully sends or receives messages. Note that \"actual throughput\" refers to the amount of messages transmitted per second during the entire experiment period, including the time of disconnection or inability to transmit. The \"average throughput\" refers to the amount of messages transmitted per second during the entire experiment period, excluding the time of disconnection or inability to transmit. In Scenario 1, the experimental results considering the actual throughput and the average throughput of the UE show that the actual throughput and the average throughput using the built-in handover algorithm of Mininet-WiFi were 81 Mbps and 127 Mbps, respectively (see Figure 7a). The actual throughput and the average throughput of the handover algorithm using DoTHa were 106 Mbps and 134 Mbps, respectively (see Figure 7b). The actual throughput and the average throughputs of the handover algorithms using OHA and OHAQR were 106 Mbps, 131 Mbps, 123 Mbps, and 135 Mbps, respectively (see Figure 7c,d). The results show that when the UE was connected to the AP, the average throughput of various handover algorithms could maintain more than 100 Mbps, but the actual throughput of the built-in handover algorithm of Mininet-WiFi was only 81 Mbps. Figure 5: The relationship between the current RSSI and time of the UE using different handover algorithms: (**a**) Mininet-WiFi; (**b**) DoTHa; (**c**) OHA; (**d**) OHAQR. Figure 6: The relationship between the currently connected AP and time of the UE using different handover algorithms: (**a**) Mininet-WiFi; (**b**) DoTHa; (**c**) OHA; (**d**) OHAQR. Figure 7: The relationship between the actual throughput and time of the UE using different handover algorithms: (**a**) Mininet-WiFi; (**b**) DoTHa; (**c**) OHA; (**d**) OHAQR. The experimental results on the average packet loss rate show that the average packet loss rate of the built-in handover algorithm using Mininet-WiFi was 8%, which was the worst among the four handover methods. The average packet loss rates of handover algorithms using DoTHa, OHA, and OHAQR were 5%, 7%, and 5%, respectively. In Scenario 2 and Scenario 3, four handover algorithms were also used, and experiments were conducted on the number of handovers, average throughput, average packet loss rate, and actual throughput. The experimental results of the four handover algorithms in the three scenarios are summarized in Table 3.  
In Scenario 1, the Avg. TP of the four algorithms was higher than 127 Mbps, and the PLR was lower than 8%. However, the number of handovers of the DoTHa algorithm was 248, which shows that its ping-pong effect was serious, and it was not suitable for this scenario. The proposed OHA algorithm was excellent in terms of the number of handovers and only handed over 13 times, which was 23.53% better than the Mininet-WiFi algorithm. The OHAQR algorithm required 15 handovers to ensure QoS requirements, but its Act. TP was 123 Mbps, Avg. TP was 135 Mbps, and PLR was 5%. The OHAQR algorithm had excellent performance and showed improvements over the Mininet-WiFi algorithm of 11.76%, 51.85%, 6.3%, and 37.5% in the number of handovers, Act. TP, Avg. TP, and PLR, respectively. In Scenario 2, the Avg. TP of the four algorithms was higher than 125 Mbps, and the PLR was lower than 10%.