Performance analysis of IEEE 802.11e over WMNs

Wireless mesh networks (WMN) are delivering wireless services for a large variety of applications in personal, local, campus, and metropolitan areas. Unlike WLANs, WMN are self-configuring systems where each Access Point (AP) can relay messages on behalf of others, thus increasing the range and available bandwidth. IEEE 802.11 has a drawback that it does not provide differentiation for better service for real-time multimedia traffic as compared to best-effort traffic applications. Further, it supports only single hop networks. These drawbacks motivate us to overcome these we implement an IEEE 802.11e amendment to IEEE 802.11 that defines a set of Quality of Service (QoS) enhancements for wireless LAN applications through modifications to the Media Access Control (MAC) layer. Basic NS2 environment does not provide 802.11e EDCA and HCCA standards but here we implement 802.11e EDCA for wireless network simulations in the network simulator tool (NS2) and to do performance analysis for multi hop WMNs. Our simulations show improved performance throughput in applications and also reduced degradation with increase in number of nodes to be serviced in the network.