ReWeave: Traffic Engineering with Robust Path Weaving for Localized Link Failure Recover

Abstract: Link failures occur frequently in Internet Service Provider (ISP) networks and pose significant challenges for Traffic Engineering (TE). Existing TE schemes either reroute traffic over vulnerable static paths, leading to performance degradation, or precompute backup routes for a broad range of failure scenarios, which introduces high overhead and limits scalability. Hence, an effective failure recovery mechanism is required to offer sufficient path diversity under constrained overhead, thereby ensuring robust and performant network operation. This paper presents ReWeave, a scalable and efficient link-level TE scheme that enables localized rerouting by equipping each link with a compact set of adjacent-only backup paths. Upon detecting a failure, only the routers at both ends of the failed link reroute traffic dynamically using SRv6-based detours, without controller intervention or full-path recomputation. Evaluation results on large-scale backbone networks demonstrate that ReWeave outperforms existing TE schemes in link failure scenarios. Compared to HARP, the state-of-the-art failure recovery scheme based on centralized control and dynamic traffic reallocation, our approach reduces the average maximum link utilization by 10.5%~20.1%, and lowers the worst-case utilization by 29.5%~40.9%. When compared with Flexile, a protection-based scheme that precomputes routes for multi-failure scenarios, ReWeave achieves a similarly low packet loss rate in 90% of failure cases, while maintaining a response speed comparable to the fastest router-based local rerouting schemes.