ZyXEL Communications G220F Users manual

ZyXEL G-220F

802.11g Wireless USB Adapter

User's Guide

Version 1.00

October 2004

ZyXEL G-220F User’s Guide

Copyright

Copyright ©2004 by ZyXEL Communications Corporation

The contents of this publication may not be reproduced in any part or as a whole, transcribed, stored in a
retrieval system, translated into any language, or transmitted in any form or by any means, electronic,
mechanical, magnetic, optical, chemical, photocopying, manual, or otherwise, without the prior written
permission of ZyXEL Communications Corporation.

Published by ZyXEL Communications Corporation. All rights reserved.

Disclaimer

ZyXEL does not assume any liability arising out of the application or use of any products, or software
described herein. Neither does it convey any license under its patent rights nor the patents' rights of others.
ZyXEL further reserves the right to make changes in any products described herein without notice. This
publication is subject to change without notice.

Trademarks

Trademarks mentioned in this publication are used for identification purposes only and may be properties
of their respective owners.

Copyright ii

ZyXEL G-220F User’s Guide

ZyXEL Limited Warranty

ZyXEL warrants to the original end user (purchaser) that this product is free from any defects in materials
or workmanship for a period of up to two (2) years from the date of purchase. During the warranty period
and upon proof of purchase, should the product have indications of failure due to faulty workmanship
and/or materials, ZyXEL will, at its discretion, repair or replace the defective products or components
without charge for either parts or labor and to whatever extent it shall deem necessary to restore the product
or components to proper operating condition. Any replacement will consist of a new or re-manufactured
functionally equivalent product of equal value, and will be solely at the discretion of ZyXEL. This warranty
shall not apply if the product is modified, misused, tampered with, damaged by an act of God, or subjected
to abnormal working conditions.

NOTE

Repair or replacement, as provided under this warranty, is the exclusive remedy of the purchaser. This
warranty is in lieu of all other warranties, express or implied, including any implied warranty of
merchantability or fitness for a particular use or purpose. ZyXEL shall in no event be held liable for
indirect or consequential damages of any kind of character to the purchaser.

To obtain the services of this warranty, contact ZyXEL's Service Center for your Return Material
Authorization (RMA) number. Products must be returned Postage Prepaid. It is recommended that the unit
be insured when shipped. Any returned products without proof of purchase or those with an out-dated
warranty will be repaired or replaced (at the discretion of ZyXEL) and the customer will be billed for parts
and labor. All repaired or replaced products will be shipped by ZyXEL to the corresponding return address,
Postage Paid. This warranty gives you specific legal rights, and you may also have other rights that vary
from country to country.

Online Registration

Register online at www.zyxel.com

for free future product updates and information.

ZyXEL Limited Warranty iii

ZyXEL G-220F User’s Guide

Information for Canadian Users

The Industry Canada label identifies certified equipment. This certification means that the equipment meets
certain telecommunications network protective operation and safety requirements. The Industry Canada
does not guarantee that the equipment will operate to a user's satisfaction.

Before installing this equipment, users should ensure that it is permissible to be connected to the facilities
of the local telecommunications company. The equipment must also be installed using an acceptable
method of connection. In some cases, the company's inside wiring associated with a single line individual
service may be extended by means of a certified connector assembly. The customer should be aware that
compliance with the above conditions may not prevent degradation of service in some situations.

Repairs to certified equipment should be made by an authorized Canadian maintenance facility designated
by the supplier. Any repairs or alterations made by the user to this equipment, or equipment malfunctions,
may give the telecommunications company cause to request the user to disconnect the equipment.

For their own protection, users should ensure that the electrical ground connections of the power utility,
telephone lines, and internal metallic water pipe system, if present, are connected together. This precaution
may be particularly important in rural areas.

Caution

Users should not attempt to make such connections themselves, but should contact the appropriate
electrical inspection authority, or electrician, as appropriate.

Note

This digital apparatus does not exceed the Class B limits for radio noise emissions from digital apparatus
set out in the radio interference regulations of Industry.

iv Information for Canadian Users

ZyXEL G-220F User’s Guide

Federal Communications Commission

(FCC) Interference Statement

The device complies with Part 15 of FCC rules. Operation is subject to the following two conditions:

• This device may not cause harmful interference.

• This device must accept any interference received, including interference that may cause undesired

operations.

This equipment has been tested and found to comply with the limits for a Class B digital device pursuant to
Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful
interference in a commercial environment. This equipment generates, uses, and can radiate radio frequency
energy, and if not installed and used in accordance with the instructions, may cause harmful interference to
radio communications.

If this equipment does cause harmful interference to radio/television reception, which can be determined by
turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of
the following measures:

1. Reorient or relocate the receiving antenna.

2. Increase the separation between the equipment and the receiver.

3. Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.

4. Consult the dealer or an experienced radio/TV technician for help.

Notice 1

Changes or modifications not expressly approved by the party responsible for compliance could void the
user's authority to operate the equipment.

This product has been designed for the WLAN 2.4 GHz network throughout the EC region and
Switzerland, with restrictions in France.

Caution

1. The equipment complies with FCC RF radiation exposure limits set forth for an uncontrolled
environment, under 47 CFR 2.1093 paragraph (d)(2).

2. This Transmitter must not be co-located or operating in conjunction with any other antenna or
transmitter.

Certifications

Refer to the product page at www.zyxel.com

FCC Statement v

.

ZyXEL G-220F User’s Guide

Customer Support

When contacting your Customer Support Representative, please have the following information ready:

 Product model and serial number.

 Warranty Information.

 Date you received your product.
 Brief description of the problem and the steps you took to solve it.

LOCATION

WORLDWIDE

AMERICA

SUPPORT E-MAIL TELEPHONE1 WEB SITE METHOD

SALES E-MAIL FAX1 FTP SITE

[e-mail] [phone] www.zyxel.com

ZyXEL Communications

[e-mail]

[e-mail] [phone]

[e-mail]

[e-mail] [phone] www.zyxel.de GERMANY

[e-mail]

[e-mail] [phone] SPAIN

[e-mail]

[e-mail] [phone] www.zyxel.dk DENMARK

[e-mail]

[e-mail] [phone] www.zyxel.no NORWAY

[e-mail]

[phone] ftp.europe.zyxel.com

[phone]

[phone] ftp.us.zyxel.com

[phone]

[phone] FRANCE [e-mail]

[phone]

[phone]

[phone]

[phone]

www.europe.zyxel.com
ftp.zyxel.com

www.us.zyxel.com NORTH

www.zyxel.fr ZyXEL France

www.zyxel.es

REGULAR MAIL

ZyXEL Communications Corp.
6 Innovation Road II
Science Park
Hsinchu 300
Taiwan

ZyXEL Communications Inc.
1130 N. Miller St.
Anaheim
CA 92806-2001
U.S.A.

ZyXEL Deutschland GmbH.
Adenauerstr. 20/A2 D-52146
Wuerselen
Germany

1 rue des Vergers
Bat. 1 / C
69760 Limonest
France

Alejandro Villegas 33
1º, 28043 Madrid
Spain

ZyXEL Communications A/S
Columbusvej 5
2860 Soeborg
Denmark

ZyXEL Communications A/S
Nils Hansens vei 13
0667 Oslo
Norway

1

“+” is the (prefix) number you enter to make an international telephone call.

Customer Support vii

ZyXEL G-220F User’s Guide

SUPPORT E-MAIL TELEPHONE1 WEB SITE METHOD

LOCATION

FINLAND [e-mail] [phone] www.zyxel.fi ZyXEL Communications Oy

SALES E-MAIL FAX1 FTP SITE

[e-mail] [phone] www.zyxel.se SWEDEN

[e-mail]

[phone]

REGULAR MAIL

ZyXEL Communications A/S
Sjöporten 4, 41764 Göteborg
Sweden

Malminkaari 10
00700 Helsinki
Finland

viii Customer Support

ZyXEL G-220F User’s Guide

Table of Contents

Copyright.........................................................................................................................................ii

ZyXEL Limited Warranty ...............................................................................................................iii

Information for Canadian Users...................................................................................................iv

Federal Communications Commission (FCC) Interference Statement.....................................v

Customer Support ........................................................................................................................vii

List of Figures............................................................................................................................... xi

List of Tables................................................................................................................................ xii

Preface......................................................................................................................................... xiii

Chapter 1 Getting Started .......................................................................................................... 1-1

1.1 About Your ZyXEL G-220F ............................................................................................ 1-1

1.2 ZyXEL G-220F Hardware and Utility Installation ........................................................... 1-1

1.3 Configuration Methods................................................................................................... 1-1

1.4 Windows XP Users Only................................................................................................ 1-2

1.5 Accessing the ZyXEL Utility ........................................................................................... 1-2

1.6 ZyXEL G-220F Modes ................................................................................................... 1-3

1.6.1 Change ZyXEL G-220F Modes .............................................................................. 1-3

Chapter 2 Wireless LAN Network ............................................................................................. 2-1

2.1 Overview ........................................................................................................................ 2-1

2.1.1 IEEE 802.11g 11 Mbps Wireless LAN.................................................................... 2-1

2.1.2 SSID........................................................................................................................ 2-1

2.1.3 Channel...................................................................................................................2-1

2.1.4 Transmission Rate (Tx Rate).................................................................................. 2-2

2.1.5 Wireless Network Application ................................................................................. 2-2

2.1.6 Roaming.................................................................................................................. 2-4

2.2 Wireless LAN Security ................................................................................................... 2-5

2.2.1 Data Encryption with WEP...................................................................................... 2-5

2.3 Fragmentation Threshold............................................................................................... 2-5

2.4 RTS/CTS Threshold....................................................................................................... 2-5

2.5 Authentication Type ....................................................................................................... 2-6

2.6 Preamble Type...............................................................................................................2-7

Chapter 3 Wireless Station Mode Configuration..................................................................... 3-1

3.1 Introduction .................................................................................................................... 3-1

Table of Contents ix

ZyXEL G-220F User’s Guide

3.2 The Link Info Screen ...................................................................................................... 3-1

3.2.1 Trend Chart ............................................................................................................. 3-3

3.3 The Site Survey Screen .................................................................................................3-3

3.3.1 Connecting to a WLAN Network ............................................................................. 3-5

3.3.2 Security Settings ..................................................................................................... 3-5

3.4 The Profile Screen..........................................................................................................3-7

3.4.1 Adding a New Profile............................................................................................... 3-9

3.5 The Adapter Screen ..................................................................................................... 3-16

Chapter 4 Access Point Mode Configuration ..........................................................................4-1

4.1 Introduction..................................................................................................................... 4-1

4.1.1 Additional Setup Requirements ..............................................................................4-1

4.2 The Link Info Screen ...................................................................................................... 4-1

4.3 The Configuration Screen ..............................................................................................4-3

4.4 The MAC Filter Screen................................................................................................... 4-5

Chapter 5 Maintenance ..............................................................................................................5-1

5.1 The About Screen ..........................................................................................................5-1

5.2 Uninstalling the ZyXEL Utility .........................................................................................5-1

5.3 Upgrading the ZyXEL Utility ...........................................................................................5-3

Chapter 6 Troubleshooting........................................................................................................ 6-1

6.1 Problems Starting the ZyXEL Utility Program ................................................................6-1

6.2 Problem Connecting to an Access Point........................................................................ 6-1

6.3 Problem with the Link Status.......................................................................................... 6-2

6.4 Problems Communicating With Other Computers .........................................................6-2

Appendix A Product Specifications.............................................................................................A

Appendix B Setting up Your Computer’s IP Address................................................................C

Appendix C Access Point Mode Setup Example....................................................................... O

Appendix D Disable Windows XP Wireless LAN Configuration Tool.......................................R

Appendix E Management with Wireless Zero Configuration ....................................................Y

Appendix F Types of EAP Authentication................................................................................OO

Appendix G Index .......................................................................................................................QQ

x Table of Contents

ZyXEL G-220F User’s Guide

List of Figures

Figure 1-1 ZyXEL Utility: System Tray Icon.................................................................................. 1-2

Figure 1-2 ZyXEL Utility................................................................................................................ 1-3

Figure 2-1 IBSS Example ............................................................................................................. 2-2

Figure 2-2 BSS Example .............................................................................................................. 2-3

Figure 2-3 Infrastructure Network Example.................................................................................. 2-3

Figure 2-4 ZyXEL G-220F as an Access Point Example.............................................................. 2-4

Figure 2-5 Roaming Example....................................................................................................... 2-4

Figure 2-6 RTS Threshold ............................................................................................................ 2-6

Figure 3-1 Station Mode: Link Info................................................................................................ 3-1

Figure 3-2 Station Mode: Link Info: Trend Chart .......................................................................... 3-3

Figure 3-3 Station Mode: Site Survey........................................................................................... 3-4

Figure 3-4 Station Mode: Site Survey: Security Settings ............................................................. 3-6

Figure 3-5 Station Mode: Profile ................................................................................................... 3-8

Figure 3-6 Station Mode: Profile: Add New Profile ..................................................................... 3-10

Figure 3-7 Station Mode: Profile: Select a Channel ................................................................... 3-12

Figure 3-8 Station Mode: Profile: Wireless Settings ................................................................... 3-13

Figure 3-9 Station Mode: Profile: Security Settings .................................................................... 3-14

Figure 3-10 Station Mode: Profile: Confirm New Settings .......................................................... 3-15

Figure 3-11 Station Mode: Profile: Activate the Profile ............................................................... 3-16

Figure 3-12 Station Mode: Adapter............................................................................................. 3-17

Figure 4-1 Access Point Mode: Link Info...................................................................................... 4-2

Figure 4-2 Access Point Mode: Configuration .............................................................................. 4-3

Figure 4-3 Access Point Mode: MAC Filter .................................................................................. 4-6

Figure 5-1 About ........................................................................................................................... 5-1

Figure 5-2 Confirm Uninstall......................................................................................................... 5-2

Figure 5-3 Uninstalling the ZyXEL Utility ...................................................................................... 5-2

List of Figures xi

ZyXEL G-220F User’s Guide

List of Tables

Table 1-1 ZyXEL Utility: System Tray Icon....................................................................................1-2

Table 2-1 IEEE 802.11G ...............................................................................................................2-1

Table 3-1 Station Mode: Link Info .................................................................................................3-2

Table 3-2 Station Mode: Link Info: Trend Chart ............................................................................3-3

Table 3-3 Station Mode: Site Survey ............................................................................................3-4

Table 3-4 Station Mode: Site Survey: Security Settings ............................................................... 3-6

Table 3-5 Station Mode: Profile..................................................................................................... 3-8

Table 3-6 Station Mode: Profile: Add New Profile ....................................................................... 3-10

Table 3-7 Station Mode: Profile: Select a Channel..................................................................... 3-12

Table 3-8 Station Mode: Adapter.................................................................................................3-17

Table 4-1 Access Point Mode: Link Info........................................................................................ 4-2

Table 4-2 Access Point Mode: Configuration................................................................................ 4-4

Table 4-3 Access Point Mode: MAC Filter .................................................................................... 4-6

Table 5-1 About............................................................................................................................. 5-1

Table 6-1 Troubleshooting Starting ZyXEL Utility Program........................................................... 6-1

Table 6-2 Troubleshooting Access Point Connection Problem ..................................................... 6-1

Table 6-3 Troubleshooting Link Quality ........................................................................................6-2

Table 6-4 Troubleshooting Communication Problem.................................................................... 6-2

xii List of Tables

ZyXEL G-220F User’s Guide

Preface

Congratulations on the purchase of your new ZyXEL G-220F!

About This User's Guide

This manual provides information about the ZyXEL Wireless LAN Utility.

Syntax Conventions

• “Type” or “Enter” means for you to type one or more characters. "Select" or "Choose" means for
you to use one of the predefined choices.

• Mouse action sequences are denoted using a comma. For example, “click the Apple icon, Control
Panels and then Modem” means first click the Apple icon, then point your mouse pointer to
Control Panels and then click Modem.

• Window and command choices are in Bold Times New Roman font. Predefined field choices are
in Bold Arial font.

• The ZyXEL G-220F 802.11g Wireless USB Adapter is referred to as the ZyXEL G-220F in this
guide.

• The ZyXEL Wireless LAN Utility may be referred to as the ZyXEL WLAN Utility or, simply, as
the ZyXEL Utility in this guide.

Related Documentation

 Support Disk

Refer to the included CD for support documents and device drivers.

 Quick Installation Guide

Our Quick Installation Guide is designed to help you get your ZyXEL G-220F up and running
right away. It contains a detailed easy-to-follow connection diagram and information on installing
your ZyXEL G-220F.

 ZyXEL Glossary and Web Site

Please refer to www.zyxel.com
documentation.

User Guide Feedback

Help us help you. E-mail all User’s Guide-related comments, questions or suggestions for improvement to
[e-mail] or send regular mail to The Technical Writing Team, ZyXEL Communications
Corp., 6 Innovation Road II, Science-Based Industrial Park, Hsinchu, 300, Taiwan. Thank you.

for an online glossary of networking terms and additional support

Preface xiii

ZyXEL G-220F User’s Guide

Graphics Icons Key

Wireless Access Point

Server

Telephone

Computer

Modem

Switch

Notebook computer

Wireless Signal

Router

xiv Preface

ZyXEL G-220F User’s Guide

Chapter 1

Getting Started

This chapter introduces the ZyXEL G-220F and prepares you to use the ZyXEL Utility.

1.1 About Your ZyXEL G-220F

The ZyXEL G-220F is an IEEE 802.11g compliant wireless LAN adapter. With the ZyXEL G-220F, you
can enjoy the wireless mobility within the coverage area.

The following lists the main features of your ZyXEL G-220F.

• Your ZyXEL G-220F can communicate with other IEEE 802.11b/g compliant wireless devices.

• Automatic rate selection.

• Offers 64-bit, 128-bit and 256-bit WEP (Wired Equivalent Privacy) data encryption for network

security.

• Proprietary SoftAP feature turns your ZyXEL G-220F into an access point (AP).

• Low CPU utilization allowing more computer system resources for other programs.

• A built-in antenna

• Plug-and-play installation for Windows ME, Windows 2000 and Windows XP.

• Driver and utility support for Windows 98 Second Edition, Windows ME, Windows 2000 and

Windows XP.

1.2 ZyXEL G-220F Hardware and Utility Installation

Follow the instructions in the Quick Installation Guide to install the ZyXEL Utility and make hardware
connections.

1.3 Configuration Methods

To configure your ZyXEL G-220F, use one of the following applications:

 Wireless Zero Configuration (WZC) (recommended for Windows XP)

 Odyssey Client Manager (recommended if you want to configure WPA or WPA-PSK with Windows

98 Second Edition, Windows ME or Windows 2000)

 ZyXEL Utility (required when you want to use the ZyXEL G-220F as an access point)

Getting Started 1-1

ZyXEL G-220F User’s Guide

DO NOT use the Windows XP configuration tool or the Odyssey Client Manager

and the ZyXEL Utility at the same time.

The bundled Odyssey Client Manager only works for your ZyXEL G-220F. Do NOT

use the Odyssey Client Manager to configure non-ZyXEL WLAN adapters.

Refer to the Odyssey Client Manager documentation for more information.

1.4 Windows XP Users Only

You must disable WZC if you want to use the ZyXEL utility. Refer to the appendices on how to deactivate
WZC or how to use WZC to manage the ZyXEL G-220F.

1.5 Accessing the ZyXEL Utility

After you install and start the ZyXEL Utility, an icon for the ZyXEL Utility appears in the system tray.

When the ZyXEL Utility system tray icon displays, the ZyXEL G-220F is installed

properly.

Figure 1-1 ZyXEL Utility: System Tray Icon

The color of the ZyXEL Utility system tray icon indicates the status of the ZyXEL G-220F. Refer to the
following table for details.

Table 1-1 ZyXEL Utility: System Tray Icon

COLOR DESCRIPTION

Red The ZyXEL G-220F is operating in wireless station mode but is not connected to a wireless

network.

Green The ZyXEL G-220F is operating in wireless station mode and connected to a wireless

network.

Pale Blue The ZyXEL G-220F is operating in access point mode.

Double-click on the ZyXEL Wireless LAN Utility icon in the system tray to open the ZyXEL Utility. The
ZyXEL Utility screens are similar in all Microsoft Windows versions. Screens for Windows XP are shown.

1-2 Getting Started

ZyXEL G-220F User’s Guide

Click the icon (located in the top right corner) to display the on-line help

window.

1.6 ZyXEL G-220F Modes

You can set your ZyXEL G-220F to operate in either wireless station or access point (AP) modes.

In wireless station mode, your ZyXEL G-220F must connect to a peer wireless station or an AP to take part
in your wireless network.

In access point mode, your ZyXEL G-220F functions as an access point. This allows you to set up your
wireless network without using a dedicated AP device. Up to 16 wireless stations can associate to the
ZyXEL G-220F to form a wireless network. Refer to Section 4.1 for more information.

1.6.1 Change ZyXEL G-220F Modes

To change between the modes, select either the Station Mode or AP Mode option in the any ZyXEL
Utility screens.

Figure 1-2 ZyXEL Utility

Getting Started 1-3

ZyXEL G-220F User’s Guide

Wait for about five seconds for the ZyXEL Utility to complete the mode change.

The current mode is indicated by the color of the radio button.

When you use the Windows XP configuration tool and the ZyXEL Utility to

configure the ZyXEL G-220F at the same time, the ZyXEL G-220F automatically

operates in wireless station mode and doesn’t allow any configuration change.

1-4 Getting Started

ZyXEL G-220F User’s Guide

Chapter 2

Wireless LAN Network

This chapter provides background information on wireless LAN network.

2.1 Overview

This section describes the wireless LAN network terms and applications.

2.1.1 IEEE 802.11g 11 Mbps Wireless LAN

IEEE 802.11g is fully compatible with the IEEE 802.11b standard. This means an IEEE 802.11b radio card
can interface directly with an IEEE 802.11g wireless device (and vice versa) at 11 Mbps or lower
depending on range. IEEE 802.11g has several intermediate rate steps between the maximum and minimum
data rates. The IEEE 802.11g data rate and modulation are as follows:

Table 2-1 IEEE 802.11G

DATA RATE (MBPS) MODULATION

1 DBPSK (Differential Binary Phase Shift Keyed)

2

DQPSK (Differential Quadrature Phase Shift Keying

)

5.5 / 11 CCK (Complementary Code Keying)

6/9/12/18/24/36/48/54 OFDM (Orthogonal Frequency Division Multiplexing)

The ZyXEL G-220F may be prone to RF (Radio Frequency) interference from other

2.4 GHz devices such as microwave ovens, wireless phones, Bluetooth enabled
devices, and other wireless LANs.

2.1.2 SSID

The SSID (Service Set Identity) is a unique name shared among all wireless devices in a wireless network.
Wireless devices must have the same SSID to communicate with each other.

2.1.3 Channel

A radio frequency used by a wireless device is called a channel.

Wireless LAN Network 2-1

ZyXEL G-220F User’s Guide

2.1.4 Transmission Rate (Tx Rate)

The ZyXEL G-220F provides various transmission (data) rate options for you to select. Options include

Fully Auto, 1 Mbps, 2 Mbps, 5.5 Mbps, 11 Mbps, 6 Mbps, 9 Mbps, 12 Mbps, 18 Mbps, 24 Mbps, 36
Mbps, 48 Mbps, and 54 Mbps. In most networking scenarios, the factory default Fully Auto setting

proves the most efficient. This setting allows your ZyXEL G-220F to operate at the maximum transmission
(data) rate. When the communication quality drops below a certain level, the ZyXEL G-220F automatically
switches to a lower transmission (data) rate. Transmission at lower data speeds is usually more reliable.
However, when the communication quality improves again, the ZyXEL G-220F gradually increases the
transmission (data) rate again until it reaches the highest available transmission rate.

You can select any of the above options. If you wish to balance speed versus reliability, select 54 Mbps in
a networking environment where you are certain that all wireless devices can communicate at the highest
transmission (data) rate. 1 Mbps or 2 Mbps are used often in networking environments where the range of
the wireless connection is more important than speed.

With USB1.1, the ZyXEL G-220F can only transmit at up to 11Mbps.

2.1.5 Wireless Network Application

Wireless LAN works in either of the two modes: ad-hoc and infrastructure.

To connect to a wired network within a coverage area using Access Points (APs), set the ZyXEL G-220F
operation mode to Infrastructure (BSS). An AP acts as a bridge between the wireless stations and the
wired network. In case you do not wish to connect to a wired network, but prefer to set up a small
independent wireless workgroup without an AP, use the Ad-hoc (IBSS) (Independent Basic Service Set)
mode.

Ad-Hoc (IBSS)

Ad-hoc mode does not require an AP or a wired network. Two or more wireless stations communicate
directly to each other. An ad-hoc network may sometimes be referred to as an Independent Basic Service
Set (IBSS).

Figure 2-1 IBSS Example

2-2 Wireless LAN Network

ZyXEL G-220F User’s Guide

Figure 2-2 BSS Example

A series of overlapping BSS and a network medium, such as an Ethernet forms an Extended Service Set
(ESS) or infrastructure network. All communication is done through the AP, which relays data packets to
other wireless stations or devices connected to the wired network. Wireless stations can then access
resource, such as the printer, on the wired network.

Figure 2-3 Infrastructure Network Example

Access Point Mode

The following figure depicts a network example in which you set the ZyXEL G-220F in access point mode.

Wireless LAN Network 2-3

ZyXEL G-220F User’s Guide

Figure 2-4 ZyXEL G-220F as an Access Point Example

In the example, the ZyXEL G-220F is installed on computer A and set to operate in access point mode.
Computer A shares Internet connection to the wireless LAN, so wireless stations B and C can access the
Internet.

2.1.6 Roaming

In an infrastructure network, wireless stations are able to switch from one BSS to another as they move
between the coverage areas. During this period, the wireless stations maintain uninterrupted connection to
the network. This is roaming. As the wireless station moves from place to place, it is responsible for
choosing the most appropriate AP depending on the signal strength, network utilization or other factors.

The following figure depicts a roaming example. When wireless station B moves to position X, the ZyXEL
G-220F in wireless station B automatically switches the channel to the one used by access point 2 in order
to stay connected to the network.

Figure 2-5 Roaming Example

2-4 Wireless LAN Network

ZyXEL G-220F User’s Guide

2.2 Wireless LAN Security

Wireless LAN security is vital to your network to protect wireless communications.

Configure the wireless LAN security using the Configuration or the Profile Security Settings screen. If
you do not enable any wireless security on your ZyXEL G-220F, the ZyXEL G-220F’s wireless
communications are accessible to any wireless networking device that is in the coverage area.

2.2.1 Data Encryption with WEP

WEP (Wired Equivalent Privacy) encryption scrambles all data packets transmitted between the ZyXEL G­220F and the AP or other wireless stations to keep network communications private. Both the wireless
stations and the access points must use the same WEP key for data encryption and decryption.

There are two ways to create WEP keys in your ZyXEL G-220F.

• Automatic WEP key generation based on a “password phrase” called a passphrase. The passphrase
is case sensitive. You must use the same passphrase for all WLAN adapters with this feature in the
same WLAN.
For WLAN adapters without the passphrase feature, you can still take advantage of this feature by
writing down the four automatically generated WEP keys from the Security Settings screen of the
ZyXEL Utility and entering them manually as the WEP keys in the other WLAN adapter(s).

• Enter the WEP keys manually.

Your ZyXEL G-220F allows you to configure up to four 64-bit, 128-bit or 256-bit WEP keys and only one
key is used as the default key at any one time.

2.3 Fragmentation Threshold

A Fragmentation Threshold is the maximum data fragment size (between 256 and 2432 bytes) that can be sent in the wireless network before the ZyXEL G-220F will fragment the packet into smaller data frames.

A large Fragmentation Threshold is recommended for networks not prone to interference while you
should set a smaller threshold for busy networks or networks that are prone to interference.

If the Fragmentation Threshold value is smaller than the RTS/CTS Threshold value (see previously) you set then the RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data frames will be fragmented before they reach RTS/CTS Threshold size.

2.4 RTS/CTS Threshold

A hidden node occurs when two stations are within range of the same access point, but are not within range
of each other. The following figure illustrates a hidden node. Both stations are within range of the access
point (AP) or wireless gateway, but out-of-range of each other, so they cannot “hear” each other, that is
they do not know if the channel is currently being used. Therefore, they are considered hidden from each
other.

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ZyXEL G-220F User’s Guide

Figure 2-6 RTS Threshold

When station A sends data to the AP, it might not know that the station B is already using the channel. If
these two stations send data at the same time, collisions may occur when both sets of data arrive at the AP
at the same time, resulting in a loss of messages for both stations.

RTS/CTS Threshold is designed to prevent collisions due to hidden nodes. An RTS/CTS Threshold
defines the biggest size data frame you can send before an RTS (Request To Send)/CTS (Clear to Send)
handshake is invoked.

When a data frame exceeds the RTS/CTS Threshold value you set (between 0 to 2432 bytes), the station
that wants to transmit this frame must first send an RTS (Request To Send) message to the AP for
permission to send it. The AP then responds with a CTS (Clear to Send) message to all other stations within
its range to notify them to defer their transmission. It also reserves and confirms with the requesting station
the time frame for the requested transmission.

Stations can send frames smaller than the specified RTS/CTS Threshold directly to the AP without the
RTS (Request To Send)/CTS (Clear to Send) handshake.

You should only configure RTS/CTS Threshold if the possibility of hidden nodes exists on your network
and the “cost” of resending large frames is more than the extra network overhead involved in the RTS
(Request To Send)/CTS (Clear to Send) handshake.

If the RTS/CTS Threshold value is greater than the Fragmentation Threshold value (see next), then the
RTS (Request To Send)/CTS (Clear to Send) handshake will never occur as data frames will be fragmented
before they reach RTS/CTS Threshold size.

Enabling the RTS Threshold causes redundant network overhead that could

negatively affect the throughput performance.

2.5 Authentication Type

The IEEE 802.11b standard describes a simple authentication method between the wireless stations and
AP. Three authentication modes are defined: Auto, Open System and Shared Key.

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ZyXEL G-220F User’s Guide

Open System mode is implemented for ease-of-use and when security is not an issue. The wireless station
and the AP do not share a secret key. Thus the wireless stations can associate with any AP and listen to any
data transmitted plaintext.

Shared Key mode involves a shared secret key to authenticate the wireless station to the AP. This requires
you to enable the WEP encryption and specify a WEP key on both the wireless station and the AP.

Auto authentication mode allows the ZyXEL G-220F to switch between the open and shared key
authentication modes automatically. Use the auto mode if you do not know the authentication mode of the
other wireless stations.

2.6 Preamble Type

A preamble is used to synchronize the transmission timing in your wireless network. There are two
preamble modes: Long Preamble and Short Preamble.

Short preamble takes less time to process and minimizes overhead, so it should be used in a good wireless
network environment when all wireless stations support it.

Select Long Preamble if you have a ‘noisy’ network or are unsure of what preamble mode the access point
or the other wireless stations support as all IEEE 802.11b compliant wireless adapters must support long
preamble. However, not all wireless adapters support short preamble. Use long preamble if you are unsure
what preamble mode the wireless adapters support, to ensure interpretability between the ZyXEL G-220F
and the access point/wireless stations and to provide more reliable communication in ‘noisy’ networks.

Select Auto to have the ZyXEL G-220F automatically use short preamble when all access point/wireless
stations support it, otherwise the ZyXEL G-220F uses long preamble.

The ZyXEL G-220F and the access point/wireless stations MUST use the same preamble mode in order to
communicate.

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ZyXEL G-220F User’s Guide

Chapter 3

Wireless Station Mode Configuration

This chapter shows you how to configure your ZyXEL G-220F in wireless station mode.

3.1 Introduction

To set your ZyXEL G-220F in wireless station mode, refer to Section 1.6.1.

3.2 The Link Info Screen

When the ZyXEL Utility starts, the Link Info screen displays, showing the current configuration and
connection status of your ZyXEL G-220F.

Figure 3-1 Station Mode: Link Info

The following table describes the labels in this screen.

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Table 3-1 Station Mode: Link Info

LABEL DESCRIPTION

AP Mode

Station Mode

Wireless Network Status

Profile Name This is the name of the profile you are currently using.

Network Name
(SSID)

AP MAC Address This field displays the MAC address of the wireless device to which the ZyXEL G-220F

Network Type

Transmission Rate This field displays the current transmission rate of the ZyXEL G-220F in megabits per

Security

Channel This field displays the radio channel the ZyXEL G-220F is currently using.

Statistics

Transmit Rate This field displays the current data transmission rate in kilobits per second (Kbps).

Receive Rate This field displays the current data receiving rate in kilobits per second (Kbps).

Authentication This field displays the authentication method of the ZyXEL G-220F.

Wireless Mode This field indicates the wireless standard (802.11b or 802.11g) of the wireless device.

Total Transmit This field displays the total number of data frames transmitted.

Total Receive This field displays the total number of data frames received.

Signal Strength This field displays the signal strength of the ZyXEL G-220F.

Trend Chart Click this button to display the real-time statistics of the data rate in kilobits per second

Signal Strength The status bar shows the strength of the signal.

Link Quality The status bar shows the quality of the signal.

Use the radio button to set the ZyXEL G-220F to operate in wireless station or access
point mode.

Refer to Section 1.6 for more information.

The SSID identifies the Service Set to which a wireless station is associated. This field
displays the name of the wireless device to which the ZyXEL G-220F is associated.

is associated.

This field displays the network type (Infrastructure(BSS) or Ad Hoc) of the wireless
network.

second (Mbps).

This field displays whether WEP data encryption is activated (WEP) or inactive
(Disabled).

This field displays G Only, B Only or Mixed Mode.

(Kbps).

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ZyXEL G-220F User’s Guide

3.2.1 Trend Chart

Click Trend Chart in the Link Info screen to display a screen as shown below. Use this screen to view real-time data traffic statistics.

Figure 3-2 Station Mode: Link Info: Trend Chart

The following table describes the labels in this screen.

Table 3-2 Station Mode: Link Info: Trend Chart

LABEL DESCRIPTION

Transmit This field displays the current data transmission rate in kilobits per second (Kbps).

Receive This field displays the current data receiving rate in kilobits per second (Kbps).

3.3 The Site Survey Screen

Use the Site Survey screen to scan for and connect to a wireless network automatically.

Wireless Station Mode Configuration 3-3

ZyXEL G-220F User’s Guide

Figure 3-3 Station Mode: Site Survey

The following table describes the labels in this screen.

Table 3-3 Station Mode: Site Survey

LABEL DESCRIPTION

Available Network List

Click a column heading to sort the entries.

,

security is activated.

,

or

deactivated.

activated.

deactivated.

denotes that the wireless device is in infrastructure mode and the wireless

denotes that the wireless device is in infrastructure mode but the wireless security is

denotes that the wireless device is in Ad-Hoc mode and the wireless security is

denotes that the wireless device is in Ad-Hoc mode but the wireless security is

3-4 Wireless Station Mode Configuration