This read-only Unsigned32 is the cost of using this router link to reach the AS Boundary Router described by the ASBR-Summary-LSA. It is the metric OSPF uses when choosing among internal paths toward that ASBR, so an unexpected rise can redirect traffic bound for external networks. For example, this metric rising unexpectedly could push traffic destined for routes learned through that ASBR onto a costlier internal path.