Active Multimedia Communication Systems

To maintain continuous, adaptive multimedia communication with guaranteed minimum quality of service in a combined wired and wireless environment poses a major challenge. We describe an active network architecture for multimedia communications. We introduce the novel concept of QoS-Message, which is specified by a flexible, high-level Petri net called the G-Net. Extensive research has been done at the University of Pittsburgh and elsewhere to study the property of G-Net and its application in the design of complex, reliable real-time systems. We adopt the G-Net for QoS-message specification. An active net- work architecture is describe so that based upon the feedback from the network, the optimizing transforma- tion of G-Nets enables the continuous adaptation of QoS-messages when the network environment changes dynamically. The approach guarantees continuous communication over a combined wired and wireless en- vironment. A prototype active multimedia communication system is being developed at the University of Pittsburgh. This research provides a basis for QoS-message specification, dynamic QoS-message construc- tion, a channel model and an active network architecture for adaptive multimedia communication.