Adaptive packet marking for providing differentiated services in the Internet

This paper examines the use of adaptable priority marking for providing soft bandwidth guarantees to individual connections or connection groups over the Internet. In contrast to other proposals for service differentiation which focus on providing firm performance guarantees, the proposed scheme does not require resource reservation for individual connections and can be supported with minimal changes to the network infrastructure. It uses modest support from the network in the form of priority handling for appropriately marked packets and relies on intelligent transmission control mechanisms at the edges of the network to achieve the desired throughput levels. The paper describes the control mechanisms and evaluates their behaviour in various network environments. These mechanisms are shown to have several salient features which make them suitable for deployment in an evolving Internet.