WIRELESS MESH NETWORKS

Wireless Mesh Networks

Wireless mesh networks

Chapter I

Introduction

The WMN as shown in Fig. 1 comprises the mesh routers, mesh clients and the mesh backbone infrastructure. The mesh clients are mobile and dynamic while the mesh router has static or minimal mobility. These mesh routers form the backbone infrastructure of the WMN, while the mesh clients form two level of nodes operation: at the peripherals and on the access points (AP). (Kuhlman et al., 2007, 56-77)

The WMN is similar in operation to the Mobile ad hoc network (MANET) and it employs a multihop routing mechanism from source node to destination node. However, unlike the MANET, WMN uses multiple interfaces and multiple radio frequencies. Furthermore, it uses high speed back-haul network and gateways to optimize network performance and integration with other wireless networks. The mesh routers can also be gateway nodes to the exterior internet cloud or to other networking technologies. These mesh routers operate as bridging points in inter- network and integration with other wireless devices. The AP is a node interface for hosting and retransmission; it provides integration between the mesh client and the mesh backbone infrastructure in WMN. The WMN is self-configuring, self-organizing and self-healing. These qualities make the WMN an excellent wireless access technology for multimedia and community broadband (IEEE 802.16) (Kuhlman et al., 2007, 56-77)

Chapter II

Literature review

WMN is an IEEE 802.11s standard (Kuhlman et al., 2007, 56-77)with extensive work being done by workgroups on achieving a standard for its different challenges and protocols. The modifications and adaptations of the ad hoc networks are mostly on the security and routing protocol of WMN. This has led to the adoption of wireless local access network (WLAN, IEEE 802.11i) security and WI-FI protected access (WPA) (Kuhlman et al., 2007, 56-77)for WMN. However, improvements by the standardization forums have seen enhancement in the authentication, encryption and integrity of WMN security. Moreover, as most wireless networks are now mostly seen as access- networks to internet or internet service providers (ISP), the Internet Protocol (IP) are easily configurable in achieving a better comprehensive security in the WMN architecture. The WMN unlike the ad hoc networks has commercial qualities, such as it is easily scalable, mobile and dynamic; but these characteristics also create security lapses in the WMN routing operations and MAC layer of the WMN protocol. In 2004, IEEE 802.11i formed a task group (TG) (Lashkari et al., Lashkari AH, Danesh MMS, Samadi, 45-88) to prepare and improve the standardization of the WMN. TG was to ratify and prepare the standard amendment to meet the targeted requirement for WMN (IEEE 802.11s). The use of WMN as gateway access to community broadband internet has created an increasing requirement for secure wireless communication operations. In response to the high commercial demand for multimedia and broadband network operation, due to its low cost and easy operation, highly sensitive application created a necessity for an effective and comprehensive security mechanism in WMN. (Lashkari et al., Lashkari AH, Danesh MMS, Samadi, 45-88)

WMN operates as access underlying ...