Failure Inference for shortening traffic Detours

To speed up the recovery from network failures, an extensive list of methods have been proposed. Many failurerecovery methods are proposed based on tunneling or marking, which increase the packet processing burden on routers and consume extra bandwidth. With neither tunneling nor marking, existing methods guarantee recovery from any singlelink failure if a detour for the failed link exists, but they generate long traffic detours that will degrade the network performance, and even increase the operational cost, which is undesirable to network operators. Therefore, in this paper, we propose a Failure Inference approach to shortening Traffic Detours named as FITD, which works in OSPF/IS-IS networks. FITD does not use explicit failure notification, and can infer which link fails based on traffic information. FITD guarantees recovery from any single-link failure if a detour for the failed link exists. In particular, for networks with symmetric link weights, FITD guarantees to generate shortest detours for any single-link failure.