Virtual Lans - Intel 470F - NetStructure Switch User Manual

C H A P T E
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470T Ch2.p65
R 2 Intel® NetStructure

Virtual LANs

A Virtual LAN is a logical network grouping that allows you to isolate
network traffic so members of the VLAN receive traffic only from other
members. Creating a VLAN is the virtual equivalent of physically moving a
group of devices to a separate switch (creating a Layer 2 broadcast domain).
The advantage of VLANs is that you can reduce broadcast traffic for the
entire switch, and increase security, without changing the wiring of your
network.
The 470 switches support two types of VLANs:
• Port-based
• Tag-based (IEEE 802.1Q)
Port-based VLANs
This is the simplest and most common form of VLAN. In a port-based
VLAN, the system administrator assigns the switch's ports to a specific
VLAN. For example, the system administrator can designate ports 1, 2, and
3 as part of the engineering VLAN and ports 5, 6, 7, and 8 as part of the
marketing VLAN. The advantage of port-based VLANs is that they are easy
to configure and all changes happen at the switch so they are transparent to
the users. The 470 switches support a maximum of four port-based VLANs.
A port can belong to only one VLAN at a time.
If a user changes location, the system administrator reassigns the port to the
new VLAN. Another advantage is if a switch (or hub) is connected to a port
that is part of a VLAN, all devices connected to the switch are also part of
the VLAN. You cannot exclude an individual device on that switch from
becoming part of the VLAN.
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