Pervasive Communication Lab
Modeling and Emulation of Self similar Internet Traffic
Researchers in the past have shown that network traffic whether on the Internet or on Local Area Networks is “self similar” in nature. Network traffic is a self similar phenomenon as it exhibits the same behavior at different degrees of magnification i.e. similar traffic patterns can be observed when the traffic is viewed at different time scales ranging from milliseconds to several days. This behavior results in intermittent periods of heavy traffic on any network that can lead to overflowing of traffic buffers on network devices based on traditional telecom queuing theory. Thus packet data networks require traffic modeling techniques that account for the self similar nature of network traffic. The primary objective of this project was to evaluate the web browsing experience of an end user who shares a fixed bandwidth Internet channel with a certain number of users generating self similar web traffic. The other users are simulated using web traffic simulator that generates calibrated HTTP traffic on the basis of specified traffic parameters such as web page sizes and inter-arrival timings of web requests. Further, the Internet channel is bandwidth limited using a traffic limiting utility in Linux. We developed an emulation test bed as well as the traffic emulator software. Test results showed that an end user can achieve acceptable quality of service for simple tasks such as web browsing and email exchange on a 3 Mbps Internet connection shared by up to 100 users. However, the quality of service is unacceptable for watching video over the Internet via websites such as Youtube.
Software
Traffic Emulator Software download
Build Instructions download