多项选择题Which two statements are correct regarding units in JUNOS?()
A.Units in JUNOS are always required for any interface configured with logical addresses such as IP and IPv6.
B.Units in JUNOS are only required when you are configuring sub-interfaces for inter-VLAN routing.
C.Unit numbers must match the DLCI or VCI numbers configured on the interface.
D.Unit 0 is the only value allowed on interfaces running HDLC, PPP, or for Ethernet interfaces not doing VLAN-tagging.