Abstract

Internet connectivity takes a strategic importance for a growing number of companies. Therefore, for reliability and performance reasons, many Internet service providers and corporate networks connect to at least two providers, a practice called multihoming. However, the current multihoming mechanism contributes to the explosive growth of the Internet routing tables. This growth has major implications for routers on storage requirements, protocol overhead and stability, and forwarding performance. As a consequence, the traditional way to be multihomed in IPv4 is prevented in the next generation IPv6 Internet. Many approaches for IPv6 multihoming were proposed, with little consideration for traffic engineering aspects. The aim of the thesis is to bridge this gap.

The thesis investigates the way to best provide traffic engineering for IPv6 multihomed sites. It first demonstrates that Host-Centric multihoming, the foreseen approach for IPv6 multihoming, is the most promising in terms of fault-tolerance and traffic engineering capabilities. Compared to traditional multihoming approaches, our simulation results show that Host-Centric IPv6 multihomed sites are able to obtain lower delays by leveraging the path diversity that underlies the Internet. Unfortunately, no traffic engineering mechanism is available for this multihoming approach. Therefore, this thesis next presents a technique to effectively use the multiple interdomain paths that exist between multihomed sites. The proposed mechanism allows the multihomed sites to control how their flows are distributed over the links with their providers. The mechanism is able to take into account complex and very dynamic routing policies. Finally, the thesis proposes the use of synthetic coordinates as a scalable and efficient way to help hosts in selecting the interdomain paths with the lowest delays. Experimental results with real measurements show that this mechanism allows sites to avoid all paths with really bad delays, and to most often select the lowest delay path.