Design And Implement Of QoS Moniroing System In Cognitive Networks

With the rapid development of computer networks, network topology and network, applications become more complex, and heterogeneous network integrates continuously, network behavior presents complex and difficult to predict. One of the major challenges for current communication networks is how to monitor and manage increasingly complex network; on the other hand, users have increasingly demanding on the network, but the current quality of service (QoS) provided by the network has been unable to meet the needs of users. To address these issues, in 2005, W. Thomas et al in Virginia Polytechnic Institute proposed the concept of cognitive networks. Cognitive network is a network which has a cognitive process that perceives of the current network status information, and then makes plannings,decisions and takes actions based on the information.For cognitive network, the premise for the QoS of business is to get the network real-time QoS information QoS accurately. As a result, the study of cognitive network QoS monitoring is important. Cognitive network QoS monitoring includes network status, network resources and user behavior and other aspects. This paper analyzes and compares three mainstream technology on the current network monitoring used by SNMP. NetFlow and probe, and pointes out that each technique focusing on network QoS monitoring is different. If using only one technology, it can not meet the demand for cognitive network QoS monitoring. Therefore, from the perspective of three techniques complementing each other, this article puts forward a cognitive structure of the network QoS monitoring. Based on the structure the paper designs and implements a cognitive network QoS monitoring system, which has the topology discovery, QoS parameter measurement, performance monitoring and traffic monitoring and other functions. Tested in the laboratory environment, the system can capture and present the network QoS information from multiple perspectives, which verifys the feasibility of the structure. Finally, the next step for further work is discussed.