Point To Point Wireless Bridge, The Design And Realization

This thesis concentrates on our research of designing and implementation ofPoint-to-Point Wireless Bridge (PPWBR), including the study of transmitting andreceiving Ethernet packets or wireless packets on the platform of Linux OS. Inaddition, the implementation of PPWBR protocol is also part of our research. PPWBRhas the ability of packet forwarding, filtering and of eliminating potential loops. Ourresearch mainly emphasizes on the implementation of MAC addresses filtering and ofSpanning Tree Protocol, referred to IEEE802.1d. This thesis puts forward a novelwireless access mechanism based on TDD (Time Division Duplex). This thesis covers software system design of PPWBR, which includs Ethernetpacket processing, wireless packet processing and PPWBR protocol processing. InEthernet module, we study the Network Interface (NI)'s driver, network protocolstacks in Linux kernel, and the promiscuous mode of NI. In wireless module, wepropose a wireless access mechanism named Rotation Access (RA). Furthermore, wedefine a specific wireless frame format in this module. In the last module (protocolprocessing), we make some discussion on the socket API and multi-Threadprogramming. After that, we implement the MAC address filtering and STP inaccording to IEEE802.1d in Linux user space with these programming methods. This thesis covers only software part of PPWBR with no reference to hardware. With the research mentioned in this thesis, we have achieved the goal of MACaddress filtering and supporting IEEE802.1d/STP in PPWBR system.