A Framework for QoS Guarantees for Multimedia Applications within an Endsystem

We describe a framework for providing quality-of-service guarantees within the endsystem for networked multimedia applications. Our framework integrates four components namely, QoS speciication, QoS mapping, QoS enforcement, and a protocol implementation model. The framework allows QoS speciications to be at a high level so that an application can easily specify its requirements using a small number of parameters. The second component of the framework is QoS mapping. The mapping operations derive resource requirements for each end-to-end session from the QoS parameters speciied by the application. Important resources considered are the cpu and the network connection. The third component of the framework is QoS enforcement. An important enforcement issue is providing processing guarantees for protocol code. An eecient real-time signal facility (RTSig) has been implemented to achieve this. The last component is an application level protocol implementation model. Protocol code structured according to this model can take advantage of the QoS support facilities in our framework. We also review related work in these areas and show how they t into the general framework.