QoS experiences in native IPv6 GRNET and 6NET networks

Adoption of IPv6 technology has been accelerated in the last few years but there is limited experience in the deployment of Quality of Service (QoS) for IPv6 traffic in backbone networks. As available software and hardware is designed to handle IPv4 packets, there is a need to accurately measure the performance of QoS mechanisms in an IPv6 environment. This paper discusses tests in the deployment of IPv6 QoS in core networks, namely the production dual stack GRNET and the IPv6-only 6NET networks, using both hardware and software platforms. In either case, we succeeded in delivering advanced transport services to IPv6 traffic and provided different performance guarantees to portions of traffic. The deployed QoS schema was common for IPv6 and IPv4; in most cases both v4 and v6 traffic exhibited comparable performance per class while imposing no significantly different overhead on network elements. A major conclusion of our tests is that the IPv6 QoS mechanisms are efficiently supported with state-of-the-art router cards at gigabit speeds.