AbstractsComputer Science


by Madhusanka Liyanage

Institution: University of Nice Sophia Antipolis
Department: Polytech Nice Sophia
Degree: Master's Degree
Year: 2011
Keywords: Transmission control protocol , Wireless networks, Link delay, Network coding, Scheduling policies, Media access layer, Acknowledgments, Round robin, Shortest remaining processing time, Run2C
Posted: 01/01/2017
Record ID: 2150649
Full text PDF: http://www.ee.oulu.fi/~lliyanag/Other/Madhusanka_Thesis_Ubinet.pdf


The focus of this research study is on behavior of traditional TCP over wireless links and possible improvements with scheduling and network coding. TCP was originally designed for wired networks, where random bit error rate is negligible, and congestion is the main cause of packet loss. This assumption does not always hold when end to end path includes wireless links. Then, TCP assumes that higher packet losses and unusual delays in wireless links result from congestion in the network and performance of TCP is degraded. This research study was focused on the possible improvements and alterations which can be implemented in order to get rid of the above behavior of TCP by means of scheduling and network coding at the MAC layer. In first part of the research study, we investigate the impact of MAC layer retransmission on TCP Throughput Performance over Wireless LANs. In second section, we used the network coding approaches to identify the possible improvements for link delay at the MAC layer. Different scenarios have been considered and performances are checked by simulations. Then, the simulation results are verified analytically. The third part was dedicated to analyze the performance of the intra session and inter session coding schemes for the round robin scheduling policy.