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American Fibertek SMH10p-PoE User Manual

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6.18.2 802.1Q VLAN

Virtual Local Area Network (VLAN) can be implemented on the switch to logically

create different broadcast domain.

When the 802.1Q VLAN function is enabled, all ports on the switch belong to default

VLAN of VID 1, which means they logically are regarded as members of the same

broadcast domain. The valid VLAN ID is in the range of number between 1 and 4094.

The amount of VLAN groups is up to 256 including default VLAN that cannot be

deleted.

Each member port of 802.1Q is on either an Access Link (VLAN-tagged) or a Trunk

Link (no VLAN-tagged). All frames on an Access Link carry no VLAN identification.

Conversely, all frames on a Trunk Link are VLAN-tagged. Besides, there is the third

mode—Hybrid. A Hybrid Link can carry both VLAN-tagged frames and untagged

frames. A single port is supposed to belong to one VLAN group, except it is on a

Trunk/Hybrid Link.

The technique of 802.1Q tagging inserts a 4-byte tag, including VLAN ID of the

destination port—PVID, in the frame. With the combination of Access/Trunk/Hybrid

Links, the communication across switches also can make the packet sent through

tagged and untagged ports.