Outlier Detection in Network Traffic Monitoring

Network traffic monitoring becomes, year by year, an increasingly more important branch of network infrastructure maintenance. There exist many dedicated tools for on-line network traffic monitoring that can defend the typical (and known) types of attacks by blocking some parts of the traffic immediately. However, there may occur some yet unknown risks in network traffic whose statistical description should be reflected as slow-intime changing characteristics. Such non-rapidly changing variable values probably should not be detectable by on–line tools. Still, it is possible to detect these changes with the data mining method. In the paper the popular anomaly detection methods with the application of the moving window procedure are presented as one of the approaches for anomaly (outlier) detection in network traffic monitoring. The paper presents results obtained on the real outer traffic data, collected in the Institute.