Wireless Networks

Description

You are to perform a study on data throughput in 802.11 WLAN systems. The study will be partially simulation and partially theoretical analysis. You are required to use a network simulator OMNeT++ to build an 802.11a/g WLAN to examine the throughput performance and explain the simulation results with aid of a theoretical throughput model. 802.11 standards are often characterised by channel bit rates, for example 802.11b is usually described as supporting a bit rate of 11Mbps. WLAN users will notice that actual data throughput, as perceived by the clients on a WLAN only approaches half of this value and is sometimes even less. Users will sometimes put this lower actual bit rate down to underperforming systems, but this is usually not the case. The lower throughput rate is primarily due to the MAC and physical layer overheads in the 802.11 architecture and is therefore intentional. Communication between a wireless client and an access point is governed by a strict set of protocols that introduces fixed delays in the communication channel. Indeed the delays do not change significantly despite faster underlying channel bit rates. You are to examine one of 802.11g or 802.11a standards. You can choose which one you prefer to work with, however you must state clearly in your report which standard you are focussing on. You do NOT have to put a wireless security protocol in place if the network simulator does not provide this functionality.