Continuous-media courseware server: a study of client interactions

Considerable research has gone into investigating networking and operating system mechanisms to support the transfer and playout of stored continuous media, but there is very little information available about how users actually interact with such systems. Developing a user workload characterization can help in the design and evaluation of efficient CM resource allocation and access mechanisms. The authors developed an interactive Web-based, multimedia, client-server application, known as the Multimedia Asynchronous Networked Individualized Courseware, or MANIC, which streams synchronized CM (currently audio) and HTML documents to remote users. This article presents empirical and analytic characterizations of observed user session-level behavior (for example, the length of individual sessions) and interactive behavior (for example, the time between starting, stopping, and pausing the audio within a session). The data come from a full-semester senior-level course given by the University of Massachusetts to more than 200 students who used MANIC to listen to the stored audio lectures and to view the lecture notes.