Reference Guide

VLAN | 1015
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VLAN
VLANs are supported on platforms: c e s
This chapter contains the following configuration topics:
• Create a VLAN
• Assign Interfaces to VLANs
• Enable Routing between VLANs
• Use a Native VLAN on Trunk Ports
• Change the Default VLAN ID
• Set the Null VLAN as the Default VLAN
• Enable VLAN Interface Counters
Virtual LAN Overview
A Local Area Network (LAN) is a collection of devices in the same broadcast domain. As a network
increases in size, segmenting a single broadcast domain into multiple domains improves scalability,
manageability, and security. However, doing so using physically with separate switches and routers is both
static and expensive.
Virtual LANs (VLANs) are a cost-effective method of segmenting and organizing a network. A single
switch can be divided into multiple broadcast domains so that devices can be grouped and isolated; each
logical segment is virtual LAN. Applying VLANs reduces broadcast traffic, introduces flexibility in the
placement of devices on the network, and increases network security by allowing separate policies to be
applied to each group.
VLANs can logically organize users
into groups increasing performance
Users on VLANs are not constrained
to a physical location
On a LAN users are bound to a physical location
and performance is reduced with a large number of users