The main total traffic rates for the 4, 8, and 16 sellectchem hop cases are 65.1, 48.8, and 48.8KBps, respectively, which are decided based on the number of hops to the destination and the ratio of capacity explained in [22]. The main traffic is sent from the source during 60�C360 seconds in a 420-second long simulation. The amount of background traffic varies from 0 to 24 packets per second. The results of our protocol shown in Figure 4 are the average of 30 runs, which is the same number of runs performed in [15].Figure 4Throughput comparison between AP-based proposals, MPRTP, and CMT unlimited rBuf from [15].From Figure 4, it can be clearly seen that in comparison to CMT, MPRTP, and AP-based methods (with b = 0.1 and ��max = 0.1) can achieve much higher throughput and are less susceptible to the interference from background traffic.
Even though now the implementations of both AP and MPRTP methods do not fully use feedback packets to gather the statistical information, a single feedback packet per decision interval �� (=5s in this study) can hardly affect the higher bandwidth shown here. Therefore, we can claim here that the AP-based method and MPRTP are viable alternatives to CMT, which can provide better bandwidth improvement when an application can tolerate or handle packet loss. Among UDP-based proposals, MPRTP could achieve higher bandwidth due to its accurate rule-based bandwidth prediction in cases of low interference and background traffic load. However, when congestion occurs and more packet loss is observed, the bandwidth difference becomes smaller.
Since MPRTP relies heavily on the information accuracy, the smaller difference is most likely due to the lower accuracy of rule-based bandwidth prediction of MPRTP. A similar behavior can be observed between AP+Com, which estimates delay compensation using packet loss, and AP?Com, which does not use delay compensation. With the delay compensation process added in AP+Com, the performance of the AP-based method is slightly better than in AP?Com because the compensated delay reflects the actual network conditions better and enhances the accuracy of AP in estimating delay after adjusting the traffic rate. However, the performance difference becomes smaller in the same manner to MPRTP when the load is high.
It is important to emphasize that while using much less information, that is, only delay information without delivered packet count nor lost packet count in comparison to AP+Com and MPRTP, AP?Com can achieve comparable throughput to other protocols. This is a piece of evidence of the adaptability of the AP-based methods, which uses delay fluctuations, and further supportive results will be shown in the next subsection.4.3. Mobile Scenario In this section, we evaluate the average delay of the AP-based proposals with b = 0.1 and ��max AV-951 = 0.1 in mobile scenarios.