XML-Driven Framework for Policy-Based QoS Management of IMS Networks

Policy Based Network Management (PBNM) simplifies the administration and management of communication networks. However due to the wide variety of policy representation forms, interoperability between different entities of PBNM systems becomes a concern. The Common Open Policy Service (COPS), which was standardized for policy control between a Policy Decision Function (PDF) and Policy Enforcement Point (PEP) had considerable shortfalls in efficiency and flexibility - its successor the Diameter protocol exhibits interoperability shortfalls. An XML-based policy provisioning solution presents great modeling capabilities that may overcome these shortfalls. The IP multimedia subsystem has adopted PBMN as the mechanism for resource and admission control. This paper reviews an XML- driven architecture for policy control of DiffServ networks, and explores the incorporation of the proposed architecture into the IMS framework to perform policy control and enforcement. Proof of concept results of the XML-based policy control architecture are presented alongside design requirements for using it as an alternative to diameter for IMS policy control.