Internet Traffic Characterization – An Analysis of Traffic Oscillations

Internet traffic has been changing a lot since few years in particular with the arrival of new P2P applications for exchanging audio files or movies and nowadays the knowledge we have on it is quite limited. Especially, new applications and new traffic are creating a lot of troubles and performance issues. Based on some traffic traces captured in the framework of the METROPOLIS network monitoring project, this paper exhibits the highly oscillating nature of Internet traffic, thus explaining why it is almost impossible nowadays to guarantee a stable QoS in the Internet, and also that such oscillations provoke a huge decrease of the global network QoS and performance. This paper then demonstrates that traffic oscillations can be characterized by the Hurst (LRD) parameter. In particular, this demonstration relies on a comparative study of Internet traffic depending on the transport protocol used to generate it. It is then shown that using TFRC – a congestion control mechanism whose purpose deals with providing smooth sending rates for stream oriented applications – instead of TCP, makes traffic oscillations and LRD almost disappear. This result, i.e. limiting as much as possible the oscillations of traffic sources in the Internet, then gives research directions for future Internet protocols and architectures.