Chapter 8: Virtual LANs and GVRP
106 Section I: Using the Menus Interface
VLAN Overview
This VLAN overview contains the following sections:
“VLAN Name,” next
“VLAN Identifier” on page 106
“VLAN Port Members” on page 106
“Port VLAN Identifier” on page 106
“Incoming and Outgoing Tagged and Untagged Frames” on page107
“Guidelines for Creating a VLAN” on page 108
VLAN Name To create a port-based VLAN, you must give it a name. The name should
reflect the function of the network devices that are be members of the
VLAN. Examples include Sales, Production, and Engineering.
VLAN Identifier Every VLAN in a network must have a unique number assigned to it. This
number is called the VLAN identifier (VID). This number uniquely identifies
a VLAN in the switch and the network. The factory VID is 1 for all ports.
If a VLAN consists only of ports located on one physical switch in your
network, you assign it a VID different from all other VLANs in your
network.
If a VLAN spans multiple switches, then the VID for the VLAN on the
different switches should be the same. The switches are then able to
recognize and forward frames belonging to the same VLAN even though
the VLAN spans multiple switches.
For example, if you had a VLAN titled Marketing that spanned three
AT-9000/24 Gigabit Ethernet switches, you would assign the Marketing
VLAN on each switch the same VID.

Port VLAN

Identifier

The Port VLAN Identifier (PVID) is the VLAN identifier associated with a
specific port. The PVID provides a VLAN assignment for each untagged
frame received by the switch. (See “Incoming and Outgoing Tagged and
Untagged Frames” on page 107.) The switch internally associates the
untagged frame with the VID that is equal to the PVID. The switch then
forwards this frame to one of the other member ports of that VLAN. The
default PVID value is 1.

VLAN Port

Members

You need to specify which ports on the switch are to be members of a
VLAN. A port can be specified as a member of one or more VLANs up to
255, the maximum number of VLANs supported by the switch. The factory
default VID is 1. Therefore, each port is initially configured to be a member
of VLAN 1, which is known as the default VLAN.