Long-Memory Dependence Statistical Models for DDoS Attacks Detection

DDoS attacks detection method based on modelling the variability with the use of conditional average and variance in examined time series is proposed in this article. Variability predictions of the analyzed network traffic are realized by estimated statistical models with long-memory dependence ARFIMA, Adaptive ARFIMA, FIGARCH and Adaptive FIGARCH. We propose simple parameter estimation models with the use of maximum likelihood function. Selection of sparingly parameterized form of the models is realized by means of information criteria representing a compromise between brevity of representation and the extent of the prediction error. In the described method we propose using statistical relations between the forecasted and analyzed network traffic in order to detect abnormal behavior possibly being a result of a network attack. Performed experiments confirmed effectiveness of the analyzed method and cogency of the statistical models.