Allied Telesis AT-S25 - Manual (Page 120)

Section II: Local and Telnet Mangement
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Port-based VLAN Overview
As explained in the VLAN Overview section earlier in this chapter, a
VLAN consists of a group of ports on one or more Ethernet switches that
form an independent traffic domain. Traffic generated by the end nodes
of a VLAN remains within the VLAN and does not cross over to the end
nodes of other VLANs unless there is an interconnection device, such as
a router or Layer 3 switch.
A port-based VLAN is a group of ports on a Fast Ethernet Switch that
form a logical Ethernet segment. Each port of a port-based VLAN can
belong to only one VLAN at a time.
A port-based VLAN can have as many or as few ports as desired. The
VLAN can consist of all the ports on an Ethernet switch, or just a few
ports. A port-based VLAN also can span switches and consist of ports
from multiple Ethernet switches.
Note
The AT-8316F or AT-8324 Switch is pre-configured with one port-
based VLAN. All ports on the switch are members of this VLAN,
called the Default VLAN.
The parameters that make up a port-based VLAN are described in the
following sections.
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 Each 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.
If a VLAN consists only of ports located on one physical switch in your
network, you would assign it a VID unique from all other VLANs in your
network.
If a VLAN spans multiple switches, then the VID for the VLAN on the
different switches must be the same. In this manner, the switches are
able to recognize and forward frames belonging to the same VLAN even
though the VLAN spans multiple switches.
For example, if you had a port-based VLAN titled Marketing that
spanned three AT-8324 Switches, you would assign the Marketing VLAN
on each switch the same VID.