SUMMARYDeployment of IPv6 technology in research and commercial networks has accelerated in the last few years. Inevitably, as more advanced services take advantage of the new technology, IPv6 traffi c gradually increases. Today, there is limited experience in the deployment of Quality of Service (QoS) for IPv6 traffi c in backbone networks that support the Differentiated Services framework. As available software and hardware are designed to handle IPv4 packets, there is a need to accurately measure and validate performance of QoS mechanisms in an IPv6 environment. This paper discusses tests and technical challenges in the deployment of IPv6 QoS in core networks, namely the production dual stack gigabit-speed Greek Research and Education Network (GRNET) and the IPv6-only 6NET European test network, using both hardware and software platforms. In either case, we succeeded in delivering advanced transport services to IPv6 traffi c and provided different performance guarantees to portions of traffi c. The deployed QoS schema was common to IPv6 and IPv4; in most cases both v4 and v6 traffi c exhibited comparable performance per class, while imposing no signifi cantly different overhead on network elements. A major conclusion of our tests is that the IPv6 QoS mechanisms are effi ciently supported with state-of-the-art router cards at gigabit speeds.

SUMMARYDiffServ is the basis of contemporary QoS-enabled networks. Setting up DiffServ QoS requires extensive engineering effort in dimensioning and provisioning, especially for adjacent networks under different administrations linked in a 'federated' hierarchy. The bandwidth broker is an entity that is responsible for the management of the resources and the QoS service operation in an automated way. In this paper, we present, test and compare two different architectures of bandwidth brokers: a centralized one and a distributed one. We also deal with the inter-domain operation of the bandwidth broker in order to perform end-to-end provisioning. The paper presents the relevant aspects for inter-domain operation of a bandwidth broker and focuses on pathfi nding issues. We discuss two models for inter-domain routing through bandwidth brokers, analyzing their advantages and comparing them. Copyright

This paper describes a Quality of Service (QoS) service on an IPv6 domain that aims to service aggregates of real-time traffic with minimum delay, jitter, and packet loss. It contains results from the tests that were performed in order to configure and evaluate the QoS mechanisms. As an actual example of real-time traffic, we have used the OpenH323 project, an open source H.323 implementation that has been ported to IPv6. The QoS mechanisms in IPv6 networks is still a field that has not been researched adequately, and we therefore present the results from the experiments in our IPv6 network that took advantage of the QoS mechanisms. This QoS service uses the Modular QoS CLI (MQC) mechanism and especially the Low Latency Queue feature (LLQ) in order to treat packets from real-time applications.