This read-write enumerated integer sets the logical type of the IP interface, broadcast, non-broadcast multi-access, or point-to-point, which defaults based on the underlying physical media, for example Ethernet and Token-Ring default to broadcast. An admin changes this when the physical medium doesn't match its default logical behavior, since it affects how routing protocols like OSPF treat the interface. For example, configuring a leased-line interface as ptp(3) tells OSPF to treat it as a point-to-point link rather than requiring DR/BDR election as on a broadcast segment.