Centralized policy provisioning for inter-domain IMS QOS

The IP Multimedia Subsystem (IMS) has been standardized to offer multimedia services over an Internet Protocol (IP) based infrastructure. These services require different Quality-of-Service (QoS) classes, hence the importance of providing QoS services through seamless interconnection networks is fueling an increasing interest in the Next Generation Network (NGN). A critical issue regarding deployment of a QoS service is the ability to provide the network and also the service across administrative domains. Flexible Inter-Domain QoS provisioning requires tight coordination between the session and transport levels and can not be considered as a transport level task only. Even if operators in different domains utilize IP QoS agreements, they may be incompatibly configured. In this paper we identify the limitations in the current IMS policy control architecture, and propose a centralized policy framework for Inter-Domain QoS based on the IMS architecture.