Performance Improvement of TCP Communication based on Cooperative Congestion Control in Android Terminals
Ayumi Shimada, Saneyasu Yamaguchi, Masato Oguchi · 2018
As the Internet evolves to include many very high speed and long distance network paths, the performance of TCP have improved. Particularly, modern loss-based TCPs increase the window size aggressively togain better throughput over other competing TCP sessions. Due to such aggressive strategies, a large number of packets may be backlogged and eventually dropped at the entry point to a wireless access network. Our previous work proposed CUBIC-based CWND control middleware for Android terminals to solve the backlog issue. It utilizes the measured Round Trip Time (RTT) in each terminal as an indication of the TCP ACK backlog condition at the WLAN Access Point (AP), and controls the upper limit of its CWND size to suppress excessive transmissions of its own TCP DATA packets. However, the middleware causes the severe fairness dwindling due to the timing difference of the middleware of each node when to start the control. In this study, we propose a new mechanism which takes the fairness of the transmission into account. Our new method starts control with taking cooperativeness into account. Our evaluation demonstrated that our new method gained more cooperativeness and fairness over the previous one by comprehending the situation of all other competing devices in the network.