| Wireless networks have made rapid development in recent years. Especially, wireless local area networks (WLAN) based on the IEEE 802.11 series protocols have been more and more deployed. With the development of wireless networks, Wireless Mesh Networks, compared with the traditional wireless infrastructure networks, with advantages such as flexible structured, self-organized and self-healing, is attracting interest in both research and market.The purpose of this paper is to realise wireless mesh networks based on IEEE 802.11 protocol. For this purpose, the WMNs routing protocol design guidline is discussed. Four major categorises of routing protocols, on-demand routing protocols, proactive routing protocols, source routing protocol, hop-by-hop routing protocol, are compared. The result shows that hop-by-hop routing protocols are more suitble for WMNs and proactive routing protocol are more suitable than on-demand routing protocols when the wireless link state is stable. Therefore, we use AODV, which is a hop-by-hop on demand routing protocol, as IEEE 802.11 Wireless Mesh networks' routing protocol. In this paper, we disscussed the implementation scheme of the AODV routing protocol and implements the protocol in S3C2410 and S3C2440 embedded system boards which use ARM Linux as their operating system.In this paper, we choose wireless audio and video surveillance system as the application of IEEE 802.11 WMNs. Considering the limited capacity of wireless networks and the relativly poorer processor performance of the mesh nodes, the traditional RTP protocol is not suitable for audio and video data transmission in wireless surveillance systems. This paper proposed a lightweighted streaming protocol WSSP (Wireless Surveillance Streaming Protocol) which can work smoothly in WMNs. WSSP protocol defines a frame segamentation scheme. When the size of an audio and video frame requiring transmitm is greater than the MTU, the frame will be divided into a number of small data segmanents, which can flow on the network transmission efficiency. This paper discussed the implementation of surveillance end points and surveillance clients. The surveillance end points are developped under embedded ARM Linux system while the surveillance clients are developed under Microsoft Windows system. |
