Allied Telesis AT-S79 - Manual (Page 106)

Chapter 10: Virtual LANs
106 Section I: Using the Menus Interface
Port VLAN
Identifier
When an untagged packet is received on a port in a tagged VLAN, it is
assigned to one of the VLANs of which that port is a member. The
deciding factor in this process is the Port VLAN Identifier (PVID). Both
tagged and untagged ports in a tagged VLAN must have a PVID assigned
to them. The default value of the PVID for each port is 1. The switch
associates a received untagged packet to the Group ID that matches the
PVID assigned to the port. As a result, the packet is only forwarded to
those ports that are members of that VLAN.
General Rules for
Creating a
Tagged VLAN
The following list contains a summary of the rules to observe when you
create a tagged VLAN:
ˆ Each tagged VLAN must be assigned a unique VID. If a particular
VLAN spans multiple switches, each part of the VLAN on the different
switches must be assigned the same VID.
ˆ A tagged port can be a member of multiple VLANs.
ˆ The AT-GS950/16 and AT-GS950/24 switches can support up to 48
tagged VLANS.