ZyXEL Communications Dimension ES-2008 User Manual page 71

The default VLAN ID for all ports is 1.
This feature is useful for accommodating devices that you want to
participate in the VLAN but that don't support tagging. Only one untagged
VLAN is allowed per port.
Select Enable from the drop-down list box to forward a frame whose VID is
Ingress
Filtering the same as the VID of the port.
Select Disable to forward all frames, regardless of the port's VID.
Acceptable Select All from the drop-down list box to accept all untagged or tagged
Frame Type frames.
Select Tag Only to drop all untagged frames.
VLAN
Dimension ES-2008 Ethernet Switch
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