Allied Telesis AT-S41 - Manual (Page 92)

AT-S41 User’s Guide
92
Tagged and Untagged VLAN Overview
As explained in the VLAN Overview section, a VLAN consists of a group
of ports on one or more Ethernet switches that form a logical Ethernet
segment and an independent broadcast 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 a connection
device, such as a router or Layer 3 switch.
A VLAN can consist of all the ports on an Ethernet switch, or just a few
ports. A VLAN can also span switches and consist of ports from multiple
Ethernet switches.
The parts that make up a VLAN are:
❑ VLAN name
❑ VLAN Identifier
❑ Untagged ports
❑ Tagged ports
❑ Port VLAN Identifier
VLAN Name Every VLAN in your network should be given 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. You will be
required to specify a name when you create a VLAN.
VLAN Identifier Each VLAN in a network must be assigned a number. This number is
called the VLAN identifier (VID). This number will uniquely identify each
VLAN in your network. You assign the VID number when you create the
VLAN.
If a VLAN consists of ports located on only one physical AT-8326GB stack,
you must assign it a VID unique from all other VLANs in your network.
In instances where a VLAN spans multiple AT-8326GB stacks, the VID for
the VLAN must be the same must on each stack. This enables the stacks
to recognize and forward frames belonging to the same VLAN even
though the VLAN spans multiple devices.
For example, if you had a VLAN titled Marketing that spanned three AT-
8326GB stacks, you would assign the Marketing VLAN on each stack the
same VID.