Media scaling in distributed multimedia object services

Abstract

Real-time support for multimedia streams in currently installed workstation environments has been based on resource management systems that provide mechanisms for streams with guaranteed or statistical quality of service (QoS) by admission control and resource reservation. In contrast, media scaling is a technique that dynamically adapts the load of media streams to the current availability of resources. Scaling can keep media streams meaningful to the user which would break during overload situations. Instead of interrupting the service for a stream when an overload situation is encountered, the quality of the stream is gracefully degraded when the resource load situation reaches a critical state. Since media scaling is a technique that dynamically takes actual resource load into account it can easily adapt to changing situations and has the potential to keep the system in a range of optimal load. In this article we show how media scaling can be integrated in a general system support for multimedia in order to simplify the implementation of scalable applications and support their concurrent utilization of scarce resources.