This document describes an optional extension to version 2 of the OSPF routing protocol [RFC1247] to support the transport of External Attributes associated with external routes which AS border routers have originated into OSPF between and among border routers using OSPF's reliable flooding mechanism. External Attributes are data associated with routes received and readvertised via some exterior gateway protocols, data which has meaning to, and must be distributed among, border routers running those protocols to allow external routes to be evaluated and readvertised by such routers, but which has no direct influence on routes computed by OSPF. The technique described uses a new, distinct OSPF link state advertisement (LSA) format (Type 8) to propagate external attribute information in a form which is opaque to the OSPF protocol itself but which is meaningful for border routers running appropriate exterior gateway protocols.