This attribute specifies whether this Ospf instance allows to exporting of
any routes learned from internal Bgp peers (IBGP) to Ospf. If the value
of this attribute is true, and if an export policy is specified to distribute,
then Ospf allows any IBGP routes to be distributed to Ospf. If the value
of this attribute is false, Ospf does not allow IBGP routes to be
distributed to Ospf, even if an export policy is specified to distribute.