Allied Telesis AT-S63 - Manual (Page 380)

Chapter 23: Protected Ports VLANs
380 Section V: Virtual LANs
7. Select Protected as the Type.
8. Select the ports for the protected ports VLAN by clicking the ports in
the switch image. (Designating group membership of the ports is
performed later in the procedure.)
Clicking repeatedly on a port toggles the port through the following
possible settings:
9. Click Apply.
Note
Any untagged ports you assign to the new VLAN are automatically
removed from their current untagged VLAN assignment.
Untagged port
Tagged port
Port is not a member of the VLAN