Design And Implement Of Environment Information Cognitive Protocol In Wireless LAN

Wireless LAN is widely used in military communications, personalcommunications and other fields for its mobility, flexibility, easy networking, low costand other merits. But in dense WLAN environment, WLAN network performancedrops considerably due to the lack of multi-AP and multi-user cooperative mechanism,in order to solve this problem, then the Cognitive WLAN come into being.Cognization is the key technology of Cognitive WLAN. firstly, This paperanalyzes the current WLAN relevant measurement and management agreement such as802.11K/802.11V, jointly considers WLAN’s common node and the AP measurementinformation and designs WLAN cooperative cognization protocol, this protocol enableWLAN’s common node to get available bandwidth of each reachable AP. In order toadapt to the change of the network environment much better, this paper put forward anadaptive algorithm. the algorithm can adjust wireless terminal measuring period andmeasurement information interaction time according to internet business and wirelesschannel changes.The simulation proves that: comparing non-using the algorithm,usethe algorithm with the protocol we design can reduce network blocking probability.Finally, we implement this protocol based on Linux OS in our WLAN. In order to get abetter demonstration, we write the GUI interface program with QT.