User-centric quality of service provisioning

Current Internet traffic includes a combination of peer to peer, web, and real time traffic which leads to unfair treatment for users or, when policed, an uneven distribution of resources to applications. This paper presents a novel extension to the Assured Forwarding per-hop-behaviour for a Diffserv-based network, enabling a more user-centric approach when provisioning for Quality of Service over IP networks. The proposed architecture, Congestion Aware Packet Scheduler (CAPS), is based on monitoring application-level performance metrics and adjusting resource allocation in order to optimise the end user resulting application performance while dynamically adapting to variable traffic conditions . The CAPS algorithm is validated through extensive simulations of a large Internet topology coupled with realistic traffic models. The results show that, irrespective of the combination of user traffic, the CAPS algorithm successfully manages the allocation of bandwidth across applications to provide the optimal aggregate-QoS, offering an improvement over alternative network configurations.