A generic scheme and sample implementation architecture for graceful service adaptation in multimedia database systems

Today's limitations of general purpose distributed computing environments require for multimedia database system capabilities for the graceful adaptation of Quality of Service (QoS). This requirement is particularly acute for presentational applications where possibly hundreds of multimedia presentations must be performed simultaneously. The QoS adaptations must be coordinated with each other to provide for an optimal global resource utilization and the maximal viewer acceptance. To meet this goal, we propose the distributed playout load control scheme PYLOT which may be customized by content providers and viewers. Furthermore, we describe a generic implementation framework to deploy PYLOT and demonstrate this framework based on the AMOS multimedia database management system.