Mechanisms for inter-domain QoS routing in Differentiated Service networks

In order to provide various services with different quality requirements, the current Internet is expected to turn into a QoS based Internet under the Differentiated Service (DiffServ) architecture. A variety of works have been done in the field of constraint based routing to provide QoS guaranteed or assured services by developing novel routing protocols and algorithms. However, most of these efforts focus on intra-domain routing rather than inter-domain routing. In this paper, we discuss issues of finding routes with QoS requirements among multiple domains, called inter-domain QoS routing. We first investigate the needs and problems faced when introducing inter-domain QoS routing into the Internet. Then, we present a model for inter-domain QoS routing and describe its building blocks. Finally, we present five mechanisms for operating inter-domain QoS routing in DiffServ networks.