Analysis of quality-of-service in a wide-area interactive distance learning system

Interactive distance learning (IDL) is an evolving paradigm of instruction and learning that attempts to overcome both distance and time constraints f ound in traditional classroom learning. The electronic classrooms at two si tes of the University of Oslo and two further sites in Norway overcome sepa rations in space by exchanging digital audio, video, and whiteboard informa tion via the Norwegian academic ATM-based network "Supernett II". The elect ronic classrooms are used since 1993 for teaching graduate level courses. T his paper presents measurements and analysis results of transport, applicat ion, and user level Quality-of-Service (QoS) of the electronic classrooms. We describe our general experiences with this system for synchronous IDL. T he lessons learned represent the motivation for the ongoing extension to su pport asynchronous IDL by a multimedia database system (MMDBS) to manage al l data used and generated in the electronic classrooms.