Traffic measurements

Traffic measurements are performed to assess delay and loss in a packet-switched network, and to find the load and throughput of network elements. This is done by having several measurement points and observing possibly time stamped packets as they pass by. Time stamping is conducted by using GPS synchronized clocks that have accuracy better than 100 ns. By comparing measurements from different points in the network the time delay and possible loss of packets are found. These measurements are so-called passive measurements and are done at high speed without disturbance to the traffic. Another type of measurements is active or intrusive measurements. In these measurements, probe packets are injected into the network. These packets will inevitably load the network and disturb the traffic. The measurements form the basis for characterizing the traffic offered to the network and for making models. Traffic from video and audio is of particular interest. The metrics used here are different from those used to characterize the perceived QoS of audio and video.

Relations to external projects and activities:
The SCAMPI project at UNINETT, EuroNGI, WP.JRA.5.1

Project coordinator: Peder J. Emstad
Professors: Peder J. Emstad, Øivind Kure
Scientists: Jon Kåre Hellan, Olav Kvittem, Arne Øslebø
PhD students: Anne Nevin, Astrid Undheim