A unified approach to routing protection in IP networks

Abstract

Routing failures are common on the Internet and routing protocols can not always react fast enough to recover from them, which usually cause packet delivery failures. To address the problem, fast reroute solutions have been proposed to guarantee reroute path availability and to avoid high packet loss after network failures. However, existing solutions are often specific to single type of routing protocol. It is hard to deploy these solutions together to protect Internet routing including both intra- and inter-domain routing protocols because of their individual computational and storage complexity. Moreover, most of them can not provide effective protection for traffic over failed links, especially for the bi-directional traffic. In this paper, we propose a unified fast reroute solution for routing protection under network failures. Our solution leverages identifier based direct forwarding to guarantee the effectiveness of routing protection and supports incremental deployment. In particular, enhanced protection cycle (e-cycle) is proposed to construct rerouting paths and to provide node and link protection for both intra- and inter-domain routing protocols. We evaluate our solution by simulations, and the results show that the solution provides 100% failure coverage for all end-to-end routing paths with approximately two extra Forwarding Information Base (FIB) entries. Furthermore, we report an experimental evaluation of the proposed solution in operational networks. Our results show that the proposed solution effective provides failure recovery and does not introduce processing overhead to packet forwarding.