Abstract
In today’s Internet protocol routing architecture, traffic delivery is in general based on single path selection paradigms, which is not sufficient enough in providing path-diversity. This lack of path diversity hinders the support for resilience, traffic engineering and high quality of services provisioning across the Internet and is important for both intra-domain and inter-domain networks. With the increasing importance of the Internet for delivering personal and business applications, the slow re-convergence after network failure of existing routing protocols becomes a significant problem, especially for real time multimedia services where service disruption cannot be generally tolerated. From a user perspective the work in this thesis aims to minimize this disruption. A novel multi-plane based fast network failure recovery scheme is proposed to enable controlled fast egress router switching for handling network failures. The single failure scenario is first considered and both intra-domain and inter-domain failures can be protected. Fast reroute can be achieved by immediately rerouting affected customer traffic from the default path onto a backup path when link failure occurs, thus avoiding slow interior gateway protocol re-convergence. An intelligent Internet protocol crank-back operation gives further enhancement of network protection capability against failures. Furthermore, multiple failure scenarios are also examined using similar local switch and crank-back techniques. Interior gateway protocol link weight setting plays an important role in influencing the protection coverage performance in intra-domain link failures. Therefore we present an interior gateway protocol link weight optimization scheme for backup path provisioning, which works on top of multiple routing planes. The scheme aims to optimize the path diversity among multiple routing planes. Due to the large search space of possible intra-domain link weights, in this thesis we adopt a global search method based on a genetic algorithm to optimize the interior gateway protocol link weights. Taking traffic information into consideration, we also combine the two separated research topics of fast reroute and traffic engineering. We choose bandwidth guarantees as our quality of services metric, and consider how our multi-plane techniques can be used for achieving both fast reroute and bandwidth resource optimization. Considering the limited inter-domain bandwidth capacity, we also adopt the multi-plane technology to achieve load balancing through traffic splitting. Large volumes of customer traffic can be intelligently split into sub-flows and spread among different routing planes to follow specific routing paths on each plane for our engineering objectives and service requirements to balance traffic load effectively.