Improving bandwidth estimation for Internet links by statistical methods

Network dimensioning is an important issue to provide stable and QoS-rich c ommunication services. A reliable estimation of bandwidths of links between the end-to-end path is a first step towards the network dimensioning. Path char is one of such tools for the bandwidth estimation for every link betwe en two end hosts. However, pathchar still has several problems. If unexpect edly large errors are included or if route alternation is present during th e measurement, the obtained estimation is much far from the correct one. We investigate the method to eliminate those errors in estimating the bandwid th. To increase the reliability on the estimation, the confidence interval for the estimated bandwidth is important. For this purpose, two approaches, parametric and nonparametric approaches, are investigated to add the confi dence intervals. Another important issue is the method for controlling the measurement period to eliminate the measurement overheads. In this paper, w e propose! a measurement method to adaptively control the number of measure ment data sets. Through experimental results, we show that our statistical approaches can provide the robust estimation regardless of the network cond itions.