From the point of view of the JUNOS software, interface properties belong to the following groups:
Physical interface properties, which are properties of the media type that apply to the interface device itself. You configure physical interface properties at the [edit interfaces interface-name] hierarchy level.
Logical interface properties, which include the protocol family and other properties that vary by PIC and encapsulation type, including the IP address of the interface, whether the interface supports multicast traffic, DLCIs, VCIs and VPIs, and traffic shaping. You configure logical interface properties at the [edit interfaces interface-name unit logical-unit-number] hierarchy level.
Family interface ...