Can someone verify the premise behind subinterfaces/vlans on an ASA? I'm a little confused. On a router, a subinterface or secondary interface is a logical interface using a hardware interface. No switch required. But now as I understand subinterface, also called vlans, on an ASA a switch is required. It looks like the ASA interface is merely a trunk link and the switch itself provides port capacity for different vlans. Is my understanding correct?
an asa5505 uses switchports, vlan itnerfaces, and switch like commands (such as "switchport access vlan x).
other asa's use subinterfaces - which are then trunked to switches. they use dot1q and are assigned to their vlans using the command "vlan x" in subinterface mode.