A Study of Path Protection in Self-Healing Routing

Recent routing failure accidents show that routing systems are not so stable as we estimated because most of accidents caused packet delivery failure in Internet. In order to resolve this problem, many fast reroute solutions are proposed to guarantee reroute path provision after network failures without high packet loss. However, most of these solutions are not deployed in practice, and some key issues still need further consideration, such as the route loop issue and the deployment cost issue. In this paper, we present state machine models to analyze how path protection works in self-healing routing solutions and identify the drawbacks in traditional path protection approaches. We identify several requirements of path protection approaches, and present principles of our path protection approach to protect Internet routing based on our analysis result. Furthermore, we conduct a detailed study to measure our proposed path protection approach in production networks and the study shows that availability and stability of routing systems is improved in real production networks.