Description of the Work
Analysis of the delay in the SURFnet network
SURFnet is a high-grade computer network specially reserved for higher education and research in the Netherlands. Some of the available services are conferencing (Internet using a video, audio and/or data connection) and streaming technology (offers its users the possibility of watching or listening to a video or audio file while it is being downloaded) . This kind of services has very concrete requirements of QoS that need to be guaranteed. One of them is the delay.
The goal of this M.Sc. project is to find the best delay figure (or groups of figures) for evaluating the “health” of a network. Our approach is to perform passive measurements at TCP/IP level, because we do not want to inject traffic in the network. We used the data from the M2C repository to extract the delay, since it was not possible to do the required measurements in real-time.
We focus on the round trip delay as our main metric to quantify latency. We investigate three groups of RTT figures; these figures have been proposed in literature and show RTT, its variability and its relationship with the number of hops. We compare these figures using the same data, to get an idea of the advantages and drawbacks of each of them.
Our results show that we are able to infer the performance of the network based on passive measurements of the delay and that all figures complement each other.
Keywords: Delay, passive measurements, round trip time, packets monitoring, TCP/IP, Internet, network’s measurements, SURFnet, health’s figures.
