Distributed, networked multimedia information systems will be a critical component of technology-based information infrastructures in the future. We present an infrastructure for supporting multimedia applications. We discuss various characteristics of multimedia data and the effect of the network on the required quality of presentation for multimedia data. We present a suite of synchronization protocols to support the quality of presentation. The crux of these protocols is the scheduling of multimedia information for synchronized delivery, over broadband networks with limited resources, and is identified as an NP-hard problem. We introduce two parameters which can be used to measure the performance of end-to-end synchronization protocols in a network supporting distributed multimedia applications. We propose and implement several heuristic scheduling algorithms, and compare their performance. We deduce the appropriateness of these algorithms in different types of distributed multimedia environments.

As demand for networked multimedia applications is increasing rapidly, it is important to provide these services in mobile communication environments. In this paper, we identify system requirements for base stations in order to support multimedia services. These requirements include supporting concurrent connections for multiple users, allocation of resources dynamically to satisfy diverse resource requirements for multimedia applications, and reallocation of resources during handoff incurred by user movement or newly generated calls. These requirements can be used to design an interface between land-based and mobile environments to handle one of the most challenging issues in multimedia communication: enforcing interstream and intrastream synchronizations. We propose two quality of presentation (QOP) parameters for evaluating the quality of mobile multimedia connections, and analyze the validity of these requirements.>

In this paper we present a distributed architecture for the existing and the emerging Internet for providing synchronized virtual channels (SVCs) to support presentation of multimedia information. The SVC architecture (SVCA) provides both intra-stream and inter-stream synchronization using resources available over the Internet and implementing distributed transmission scheduling mechanisms. We also propose a set of quality of presentation (QOP) parameters that quantify the quality of multimedia presentation from the user's point of view. Based on these parameters, we evaluate the proposed architecture and provides trade-offs between the QOP parameters and the required network resources to maintain this quality. Subsequently, these trade-offs are used to generate an optimal schedule for transmission of multimedia information over the SVCA. We also present protocol mechanisms to realize the SVCA.>

Proposes a communication model for pre-orchestrated multimedia information. The model is used to determine the optimal number of channels needed to transmit the multimedia information. Subsequently, the authors consider a channel-deficient system and prove that scheduling transmission of multimedia data in this system is an NP-hard problem. Accordingly, they propose a heuristic algorithm with complexity O(nlog nm), where n represents the number of data units to be communicated over m channels.>