An Optimized Clustering and Selective Probing Framework to Support Internet Quality-of-Service Routing

The advent of multimedia applications has triggered widespread interest in quality-of-service (QoS) support. An Internet-based QoS framework, Differentiated Services (DiffServ), has been proposed. The framework focuses mainly on packet scheduling. As such, it decouples routing from QoS provisioning. This typically results in inefficient routes, thereby limiting the ability of the network to support QoS requirements and to manage resources efficiently. This article proposes a scalable, clustering, and selective probing framework to assist in identifying and selecting routing paths that are very likely to meet the QoS requirements of the underlying application. The proposed approach can be seamlessly integrated into the DiffServ framework to extend its ability to support QoS requirements. A description of the basic components of the framework is provided. Scalability is achieved using a clustering algorithm, referred to as d-median, to reduce signaling and routers overhead. A thorough study to evaluate the performance of d-median is conducted. The results of the study show that, for power-law graphs such as the Internet, the d-median clustering-based approach outperforms existing clustering methods.