A framework approach to accommodation of multimedia communications for training systems

In a virtual training classroom that supports classroom interactions with real-time audio and video (A/V), we adopted the peer-to-peer model for A/V streaming. Using the Jini network technology, we integrated the peer-to-peer subsystem into the client-server centric Web-based training systems. Not only does the lookup service of the Jini network provide a mechanism for objects to discover remote services, Jini also provides the proxy and remote events, two patterns to accomplish remote control. When an object needs to control many activities associated with a remote object, the proxy pattern is more appropriate. By holding a proxy of the remote object, the controlling object can freely invoke any remote function. On the other hand, if an object needs to react to one event associated with each of the related objects, the remote event mechanism is a handier means. We also implemented an application-level simplified multipoint A/V streaming, which is useful for the companies whose networks do not support multicast over the Internet.