The Role Multimedia of Multicasting in Managing Interactive Distance Learning Systems

This paper discusses the important role ofmulticasting in designing, implementing, and managinginteractive multimedia distance learning systems. Thisis achieved in the context of IRI, an Interactive Remote Instruction system for distance learningbuilt at Old Dominion University. IRI is anInternet-based system which integrates continuousmultimedia, shared applications and a variety ofmulti-user collaborative utilities. In this paper, weconcentrate on the process architecture and dynamicmulticast group handling as they pertain to managingmultimedia resources, and show how they supportrobustness and short response time to user actions. IRIuses raw IP multicasting for audio and video streams andreliable multicasting for resource management and datasharing. The system is scalable (uses multicast for inter-process communication) andexpandable(partitioned into a setofautonomousbutcooperating components).