As mentioned before, IP is at the center of an hourglass model.
IP can run on different medias, a link, which need not always be physical (e.g.: VPN, tunnel, loopback)
For convenience, we'll separate the medias into two categories:
Local Area Network -- short to middle range (office, building, campus) networks like Ethernet, Token Ring, wireless LAN, ... These networks usually support a form of broadcast transmission.
Wide Area Network -- middle to long range (inter-campus, national, transnational) networks like leased lines, Frame Relay, satellite,
ATM seems to fit in both categories -- no one really knows -- and who cares ?