Packet Dispersion in IEEE 802.11 Wireless Networks

Packet dispersion techniques have been commonly used to estimate bandwidth in wired networks. However, current packet dispersion techniques were developed for wired network environments and can provide inaccurate results in wireless networks due to wireless capacity variability over short time scales. This paper develops an analytical model to investigate packet dispersion behavior in wireless networks. The packet dispersion model is validated using both an extended ns-2 simulator that includes 802.11 MAC layer rate adaptation and wireless 802.11b testbed measurements. Utilizing the model, this study shows that packet dispersion measures effective capacity and achievable throughput of wireless networks instead of the maximum capacity as in wired networks. Additionally, mean and variance of packet dispersion in IEEE 802.11 wireless networks is analyzed while considering the impact of channel conditions such as packet size, link rate, bit error rate and RTS/CTS