Cisco Systems Cisco Systems AT&T Labs This document specifies the extensions to OSPF that enable a router to use link-local signaling to signal the metric that receiving OSPF neighbor(s) should use for a link to the signaling router. The signaling of this reverse metric, to be used on the link to the signaling router, allows a router to influence the amount of traffic flowing towards itself and in certain use cases enables routers to maintain symmetric metrics on both sides of a link between them.