User guide

ExtremeWare 7.2e Installation and User Guide 91
5 Virtual LANs (VLANs)
This chapter covers the following topics:
Overview of Virtual LANs on page 91
Types of VLANs on page 92
VLAN Names on page 96
Configuring VLANs on the Switch on page 97
Displaying VLAN Settings on page 98
MAC-Based VLANs on page 99
on page 101
Setting up Virtual Local Area Networks (VLANs) on the switch eases many time-consuming tasks of
network administration while increasing efficiency in network operations.
Overview of Virtual LANs
The termVLAN is used to refer to a collection of devices that communicate as if they were on the
same physical LAN. Any set of ports (including all ports on the switch) is considered a VLAN. LAN
segments are not restricted by the hardware that physically connects them. The segments are defined by
flexible user groups you create with the command line interface.
Benefits
Implementing VLANs on your networks has the following advantages:
VLANs help to control traffic—With traditional networks, congestion can be caused by broadcast
traffic that is directed to all network devices, regardless of whether they require it. VLANs increase
the efficiency of your network because each VLAN can be set up to contain only those devices that
must communicate with each other.
VLANs provide extra security—Devices within each VLAN can only communicate with member
devices in the same VLAN. If a device in VLAN Marketing must communicate with devices in VLAN
Sales, the traffic must cross a routing device.
VLANs ease the change and movement of devices—With traditional networks, network
administrators spend much of their time dealing with moves and changes. If users move to a
different subnetwork, the addresses of each endstation must be updated manually.