Enhancements to OSPF Graceful Restart for Heterogeneous Environments
Y. Yang
Reliability is a fundamental concern for the network. As a solution to improve network stability, the non-stop forwarding paradigm depends on protocol recovery based on graceful restart techniques. One of the proposed graceful restart techniques for [OSPF], a widely deployed IGP, is described in [OSPF-GR]. This technique has a limitation of not being backward compatible, in the sense that if a neighbor does not support the helper mode described in [OSPF-GR], the graceful-restart procedure will fail (i.e., revert to normal restart). For large multi-vendor networks, this scenario is fairly common. In this draft, we describe techniques that can achieve OSPF graceful restart even if a neighboring router does not support the helper-mode of [OSPF-GR].