%% You should probably cite rfc9929 instead of this I-D. @techreport{ietf-lsr-igp-ureach-prefix-announce-11, number = {draft-ietf-lsr-igp-ureach-prefix-announce-11}, type = {Internet-Draft}, institution = {Internet Engineering Task Force}, publisher = {Internet Engineering Task Force}, note = {Work in Progress}, url = {https://datatracker.ietf.org/doc/draft-ietf-lsr-igp-ureach-prefix-announce/11/}, author = {Peter Psenak and Clarence Filsfils and Daniel Voyer and Shraddha Hegde and Gyan Mishra}, title = {{IGP Unreachable Prefix Announcement}}, pagetotal = 17, year = 2025, month = sep, day = 25, abstract = {Summarization is often used in multi-area or multi-domain networks to improve network efficiency and scalability. With summarization in place, there is a need to signal loss of reachability to an individual prefix covered by the summary. This enables fast convergence by steering traffic, when aplicable, away from the node which owns the prefix and is no longer reachable. This document specifies protocol mechanisms in IS-IS and OSPF, together with two new flags, to advertise such prefix reachability loss. The term OSPF in this document is used to refer to both OSPFv2 and OSPFv3.}, }