A study of the impact of traffic type and node mobility on the performance of an IEEE 802.16 WiMAX

Abstract

Mobile WiMAX is becoming an attractive solution for providing high-speed internet access in a cost-effective way to people living in both sparsely populated rural areas and densely populated urban areas. This popularity is a result of the flexibility, low-cost and user mobility offered by the technology. While WiMAX handoff and quality of service (QoS) provisioning have been explored by many network researchers, the effect of traffic type and node mobility on WiMAX has not been fully investigated yet.

This thesis reports on an empirical study of the impact of traffic type, node mobility and handoff on the performance of a typical mobile WiMAX IEEE 802.16 network. It analyses WiMAX performance for small, medium and large network scenarios under FTP, HTTP, VoIP and Video conferencing traffic with varied node mobility (0~90km/h) through extensive simulation experiments. It is observed that both FTP and HTTP are satisfactorily transmitted regardless of the volume of traffic on the network. Packet delay of less than one second is maintained regardless of increased node speeds. Packet loss ratios for VoIP and Video conferencing are irregularly high and increase when the traffic volume of the network also increases. Another observation is that average throughput of Video conferencing and m-VoIP is decreased and packet loss ratio is irregularly increased causing loss of connection. When handoff is allowed, delays in all traffic types are slightly increased, average throughput is fairly increased and packet loss ratio is also fairly decreased. As expected, both FTP and HTTP traffic are transmitted well over WiMAX because they can tolerate a certain amount of delay. However, both m-VoIP and Video conferencing packets were not moderately transmitted over the network due to high packet loss. Finally, the impact of handoff on system performance is also investigated.