Darwin: Customizable resource management for value-added network services

The Internet is rapidly changing from a set of wires and switches that carr y pockets into a sophisticated infrastructure that delivers a set of comple x value-added services to end users. Services can range from bit transport all the way up to distributed value-added services like video teleconferenc ing virtual private networking, data mining, and distributed interactive si mulations. Before such services can be supported in a general and dynamic m anner, we have to develop appropriate resource management mechanisms. These resource management mechanisms must make it possible to identify and alloc ate resources that meet service or application requirements, support both i solation and controlled dynamic shoring of resources across services and ap plications sharing physical resources, and be customizable so services and applications can toiler resource usage to optimize their performance. The D arwin project has developed a set of customizable resource management mecha nisms that support valve-added services. In this article we present and mot ivate these mechanisms, describe their implementation in a prototype system , and describe the results of a series of proof-of-concept experiments.