| Popis: |
Traffic engineering in computer and communication networks has become a very complex process. An important part of this activity is to make predictions about network traffic. Therefore, research advances in network traffic forecasting are continually emerging in the literature. Although its importance, the quality control of network traffic forecasts is commonly neglected. In this paper we analyze the performance of CUSUM, Shewhart, and EWMA control charts applied to the residuals of an ARMA(2,2) forecasting model processing real WAN and LAN traffic samples. Numerical results and graphical analysis indicate that CUSUM performs worst for all traffic samples. Shewhart chart performs better than CUSUM, but worse than EWMA since it reports false alarms for processes under control. Differently than CUSUM and Shewhart, EWMA (λ=0.1) control chart shows the best performance for all traffic patterns, showing no false alarms. |
