A policy based approach for QoS-on-demand over the Internet

This paper describes a systematic policy-based approach for offering differentiated services over a single provider's network. Emerging work in this area both in standards forums as well as in research publications, is heavily focused on the element management problem, i.e., on the specification of policy rules for managing one or more devices. However, an ISP faces the more challenging task of having to offer and deploy end-to-end services across the Internet. We take a virtual leased line service as exemplar, and describe in detail a process through which a customer's request for connectivity between multiple sites is translated into network level policies, validated, admitted, resolved into role level policies, and activated on network devices. Deliberately, this is a "big picture" paper, where we bring together various functional components (such as bandwidth brokers, directories and policy servers) and algorithms (route computation, consistency checking, admission control) to fashion a network management framework for QoS-on-demand.