Our findings show a large variation in the throughput behaviour of the IEEE 802.11b WLAN system for the different categories of signals. Models describing TCPdownT against SNR for different signal categories were statistically generated and validated. The study was carried out in small offices, open corridors and free space environments using an infrastructure based IEEE 802.11b WLAN while transmitting different quality of service (QoS) traffic all corresponding to different wireless multimedia tags. This paper presents our study on the dependence of TCP downstream throughput (TCPdownT) on signal to noise ratio (SNR) for multiple users in an IEEE 802.11b Wireless Local Area Network (WLAN) system. Simulation results show that the starvation problem is resolved with our approach, and the target throughput is met. To address this problem, based on our model, we formulate a bandwidth allocation problem to optimize the network throughput and fairness under some predefined requirements by systematically tuning the AP and stations contention windows. Simulation evaluation shows that our model predicts network performance accurately over a wide range of network sizes and indicates the existence of a throughput starvation problem. Given any number of hidden nodes, only four constraints are needed to describe the interaction between stations and the AP with the consideration of both uplink and downlink traffic. Unlike existing models, our model can accommodate different numbers of hidden nodes without increasing the model complexity. Motivated by observations from real world wireless local area network (WLAN) deployments, we develop in this paper a novel analytical model to characterize the saturation throughput of an IEEE 802.11-based access point (AP) and stations under the influence of hidden terminals.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |