Dell PowerConnect 5212 User Manual download pdf

PowerConnect Application Note #8 January 2004

www.dell.com/networking 1

VLAN-Based Network Segmentation

This Application Note relates to the following Dell PowerConnect™ products:

• PowerConnect 33xx

• PowerConnect 52xx

Abstract

This Application Note explains the benefits of using virtual local area networks (VLANs) to segment a

switched network. This document describes VLAN fundamentals and provides configuration instructions

for setting up multiple VLANs on Dell PowerConnect switches.

Applicable Network Scenarios

VLANs are useful in situations where the need exists to separate the logical topology of network

segments from the physical topology. For example, VLANs can be used to restrict a broadcast domain to

a given workgroup, enhancing both security and performance.

The following diagram shows a switched network using Dell PowerConnect 33xx and 52xx switches in a

default VLAN configuration. Client A from the accounting workgroup requires access to a central server,

while Clients B and C from the marketing workgroup should not have access to the accounting server.

Note that all switch interfaces are members of VLAN 1.This is the default configuration for all Dell

PowerConnect switches. Since all switch interfaces are members of VLAN 1 by default, all nodes

attached to both switches are members of the same broadcast domain. This configuration provides no

data privacy

PowerConnect 3324

Accounting server

1/5

VLAN 1

PowerConnect 5224

Client B

Marketing

1/15

VLAN 1

1/e1

VLAN 1

1/1

VLAN 1

Client A

Accounting

1/e10

VLAN 1

Client C

Accounting

1/e20

VLAN 1

and it can degrade application performance. Security may be compromised because Clients B and C can

see network traffic from the accounting workgroup. Performance suffers because all nodes attached to

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