Link weight optimization for enhancing IP resilience using multi-plane routing

Abstract

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. This is especially true for real time multimedia services where service disruption cannot be generally tolerated. In order to ensure fast network failure recovery, IP Fast Reroute (FRR) can be adopted to immediately reroute affected customer traffic from the default path onto a backup path when link failure occurs, thus avoiding slow Interior Gateway Protocol (IGP) re-convergence. We notice that IGP link weight setting plays an important role in influencing the protection coverage performance in intra-domain link failures. Therefore in this paper we present an IGP link weight optimization scheme for backup path provisioning, which works on top of a multi-plane enabled routing platform. 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 paper we adopted a global search method based on a Genetic Algorithm to optimize the IGP link weights. Evaluation results show that in most cases a set of optimal link weights can be found which ensures that there are no more critical shared links among all the diverse paths on each routing plane. As a result, backup paths can be always available in case of single link failures.