A methodology of effective measurement for link traffic

Precise and real time measurement of link traffic is the fundamental procedure of traffic engineering, network behavior monitoring and capacity planning. The methodology of measuring links traffic by polling every device for large-scale network will impact performance of routers and bring up heavier traffic into the network. Further more, this methodology cannot meet the requirement of time scale since there are so many SNMP supported devices in network under management. How to decide the minimal set of devices to be interrogated with the premises of traffic of every link being confirmed is the key to resolve this problem. In the paper, traffic measurement mechanism is introduced and a sufficient condition is proposed for measuring each link on the network. The sufficient condition can include the condition of weak vertex cover proposed by Yuri Breitbart. A policy of traffic measurement is designed based on the sufficient condition. An example is used to explain the process of the policy. The methodology can decrease the number of nodes to be monitored and reduce the traffic caused by measurement. The policy has been used to network management system of long-distance education project supported by NEPC.