After executing the displayinterface Ethernet 1/0/1 command on the switch SWA, the output information is as follows:

After executing the displayinterface Ethernet 1/0/1 command on the switch SWA, the output information is as follows:

[SWA]display interface Ethernet 1/0/1

Ethernet1/0/1 current state: UP

PVID: 10

Mdi type: auto

Link delay is 0(sec)

Port link-type: trunk

VLAN passing: 1 (default vlan), 10

VLAN permitted: 1 (default vlan), 2-4094

Trunk port encapsulation: IEEE 802.1q

Port priority: 0

It can be judged from the above output
A . Port Ethemet1/OM is a trunk port, which only allows data from VLAN 1 and VLAN 10 to pass through
B . Data frames without VLAN tags will be tagged with VLAN1 when they enter port Ethernet1/0/1
C . Data reconnaissance with VLAN1 tag will not be stripped when it leaves port Ethemet1/0/1
D . Port Ethemet1/0/1 is a trunk port, allowing data frames of any VLAN to pass through