NETGEAR CG814WG User manual

NETGEAR, Inc.
4500 Great America Parkway
Santa Clara, CA 95054 USA
Phone 1-888-NETGEAR
202-10074-01
February 2005
Reference Manual for the
Wireless Cable Modem
Gateway CG814WG

ii
© 2005 by NETGEAR, Inc. All rights reserved.
Trademarks
NETGEAR is a trademark of Netgear, Inc.
Microsoft, Windows, and Windows NT are registered trademarks of Microsoft Corporation.
Other brand and product names are registered trademarks or trademarks of their respective holders.
Statement of Conditions
In the interest of improving internal design, operational function, and/or reliability, NETGEAR reserves the right to
make changes to the products described in this document without notice.
NETGEAR does not assume any liability that may occur due to the use or application of the product(s) or circuit
layout(s) described herein.
FCC Warning Statement
This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions:
(1) this device may not cause harmful interference, and
(2) this device must accept any interference received, including interference that may cause undesired operation.
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 residential
installation.
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. However, there is no guarantee that
interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or
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:
• Reorient or relocate the receiving antenna.
• Increase the separation between the equipment and receiver.
• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.
• Consult the dealer or an experienced radio/TV technician for help.
CAUTION: Any changes or modifications not expressly approved by the party responsible for compliance could void
the user’s authority to operate the equipment.
Prohibition of Co-location
This device and its antenna(s) must not be co-located or operating in conjunction with any other antenna or transmitter.
Safety Information
To maintain compliance with FCC’s RF exposure guidelines, this equipment should be installed and operated with
minimum distance of 20 cm between the radiator and your body. Use the supplied antenna.

iii
Declaration of Conformity for R&TTE directive 1999/5/EC
Essential requirements – Article 3. Protection requirements for health and safety – Article 3.1a. Testing for electric
safety according to EN 60950-1 has been conducted. These are considered relevant and sufficient. Protection
requirements for electromagnetic compatibility – Article 3.1b. Testing for electromagnetic compatibility according to
EN 301 489-1 and EN 301 489-17 has been conducted. These are considered relevant and sufficient. Effective use of the
radio spectrum – Article 3.2. Testing for radio test suites according to EN 300 328- 2 has been conducted. These are
considered relevant and sufficient.
Bestätigung des Herstellers/Importeurs
Es wird hiermit bestätigt, daß das CG814WG Wireless Cable Modem Gateway gemäß der im BMPT-AmtsblVfg 243/
1991 und Vfg 46/1992 aufgeführten Bestimmungen entstört ist. Das vorschriftsmäßige Betreiben einiger Geräte (z.B.
Testsender) kann jedoch gewissen Beschränkungen unterliegen. Lesen Sie dazu bitte die Anmerkungen in der
Betriebsanleitung.
Das Bundesamt für Zulassungen in der Telekommunikation wurde davon unterrichtet, daß dieses Gerät auf den Markt
gebracht wurde und es ist berechtigt, die Serie auf die Erfüllung der Vorschriften hin zu überprüfen.
Certificate of the Manufacturer/Importer
It is hereby certified that the CG814WG Wireless Cable Modem Gateway has been suppressed in accordance with the
conditions set out in the BMPT-AmtsblVfg 243/1991 and Vfg 46/1992. The operation of some equipment (for example,
test transmitters) in accordance with the regulations may, however, be subject to certain restrictions. Please refer to the
notes in the operating instructions.
Federal Office for Telecommunications Approvals has been notified of the placing of this equipment on the market
and has been granted the right to test the series for compliance with the regulations.
Technical Support
Thank you for choosing Netgear product(s). Please register online and take advantage of the technical support resources
such as Netgear online knowledge base. Technical support is available 24 hours a day, seven days a week; please call
your Cable Internet Service Provider.
Product and Publication Details
Model Number: CG814WG
Publication Date: February 2005
Product Family: gateway
Product Name: CG814WG Wireless Cable Modem Gateway
Home or Business Product: Home
Language: English
Publication Part Number: 202-10074-01

iv

Contents i
Contents
Chapter 1 .................................................................................................................................. 
About This Manual...............................................................................................................1-1
Audience, Conventions, Publication Date ......................................................................1-1
Chapter 2 .................................................................................................................................. 
Introduction ..........................................................................................................................2-1
About the CG814WG ......................................................................................................2-1
Key Features ..................................................................................................................2-1
Built-in Cable Modem ...............................................................................................2-1
A Powerful, True Firewall .........................................................................................2-2
Content Filtering .......................................................................................................2-2
802.11b and 802.11g Standards-based Wireless Networking ..................................2-2
Configurable Auto Uplink™ Ethernet Connection ....................................................2-3
USB Port ..................................................................................................................2-3
Protocol Support ......................................................................................................2-3
Easy Installation and Management ..........................................................................2-3
What’s in the Box? ..........................................................................................................2-5
The Gateway’s Front Panel ......................................................................................2-5
The Gateway’s Rear Panel ......................................................................................2-7
Chapter 3 
Connecting the Gateway to the Internet ............................................................................3-1
What You Will Need Before You Begin ...........................................................................3-1
Hardware Requirements ..........................................................................................3-1
LAN Configuration Requirements ............................................................................3-1
Internet Configuration Requirements .......................................................................3-2
Connecting the CG814WG Gateway ..............................................................................3-2
Chapter 4 
Wireless Configuration........................................................................................................4-1
Considerations For A Wireless Network .........................................................................4-1
Implement Appropriate Security ...............................................................................4-1

ii Contents
Observe Placement and Range Guidelines .............................................................4-2
Configuring Wireless Settings ........................................................................................4-3
Wireless Network Settings .......................................................................................4-3
Wireless Access Point ..............................................................................................4-4
Restricting Wireless Access by MAC Address .........................................................4-4
Configuring Wired Equivalent Privacy (WEP) ..........................................................4-6
Chapter 5 
Protecting Your Network .....................................................................................................5-1
Protecting Access to Your CG814WG Gateway .............................................................5-1
Blocking Keywords, Sites, and Services ........................................................................5-2
Blocking Keywords and Domains .............................................................................5-3
Using MAC Filtering ........................................................................................................5-4
Using Port Blocking ........................................................................................................5-6
Port Forwarding ..............................................................................................................5-7
Using Port Triggering ....................................................................................................5-10
Setting Up A Default DMZ Host ....................................................................................5-12
Respond to Ping on Internet WAN Port .................................................................5-12
Enabling or Disabling Content Filtering Services .........................................................5-12
Chapter 6 
Managing Your Network ......................................................................................................6-1
Network Status Information ............................................................................................6-1
Viewing Gateway Status ..........................................................................................6-1
Connection Status ....................................................................................................6-3
Current System Time .........................................................................................6-3
Configuring LAN IP Settings ...........................................................................................6-4
LAN IP Setup ..................................................................................................................6-4
Using the Gateway as a DHCP Server ....................................................................6-5
DHCP Client Lease Info ....................................................................................6-6
Viewing and Emailing Logged Information .....................................................................6-7
Enabling Logs Event E-mail Notification ..................................................................6-7
Erasing Configuration .....................................................................................................6-8
Running Diagnostic Utilities ............................................................................................6-8
Enabling Remote Management Access .......................................................................6-10
Enabling Remote Management Access After a Reset ................................................. 6-11

Contents iii
Chapter 7 
Troubleshooting...................................................................................................................7-1
Basic Functions ..............................................................................................................7-1
Power LED Not On ...................................................................................................7-2
Test LED Stays On ...................................................................................................7-2
Local Link LEDs Not On ...........................................................................................7-2
Cable Link LED Not On ............................................................................................7-3
Troubleshooting the Web Configuration Interface ..........................................................7-3
Troubleshooting the ISP Connection ..............................................................................7-4
Troubleshooting a TCP/IP Network Using a Ping Utility .................................................7-4
Testing the LAN Path to Your Gateway ....................................................................7-4
Testing the Path from Your PC to a Remote Device ................................................7-5
Appendix A 
Technical Specifications .................................................................................................... A-1
Appendix B 
Networks, Routing, and Firewall Basics........................................................................... A-1
Related Publications ...................................................................................................... A-1
Basic Router Concepts .................................................................................................. A-1
What is a Router? ................................................................................................... A-2
Routing Information Protocol ................................................................................... A-2
IP Addresses and the Internet ................................................................................. A-2
Netmask .................................................................................................................. A-4
Subnet Addressing .................................................................................................. A-5
Private IP Addresses ............................................................................................... A-7
Single IP Address Operation Using NAT ................................................................. A-8
MAC Addresses and Address Resolution Protocol ................................................. A-9
Related Documents ................................................................................................. A-9
Domain Name Server ............................................................................................ A-10
IP Configuration by DHCP .................................................................................... A-10
Internet Security and Firewalls .................................................................................... A-10
What is a Firewall? .................................................................................................A-11
Stateful Packet Inspection ......................................................................................A-11
Denial of Service Attack .........................................................................................A-11
Wireless Networking Overview .................................................................................... A-12
Infrastructure Mode ............................................................................................... A-12

iv Contents
Ad Hoc Mode (Peer-to-Peer Workgroup) .............................................................. A-12
Network Name: Extended Service Set Identification (ESSID) .............................. A-13
Authentication and WEP .............................................................................................. A-13
802.11b Authentication .......................................................................................... A-13
Open System Authentication ................................................................................. A-14
Shared Key Authentication .................................................................................... A-15
Overview of WEP Parameters .............................................................................. A-16
Key Size ................................................................................................................ A-16
WEP Configuration Options .................................................................................. A-17
Wireless Channels ....................................................................................................... A-18
Ethernet Cabling .......................................................................................................... A-20
Uplink Switches and Crossover Cables ................................................................ A-20
Cable Quality ......................................................................................................... A-21
Appendix C 
Preparing Your Network ..................................................................................................... A-1
Preparing Your Computers for TCP/IP Networking ....................................................... A-1
Configuring Windows 95, 98, and Me for TCP/IP Networking ....................................... A-2
Install or Verify Windows Networking Components ................................................. A-2
Enabling DHCP in Windows 95B, 98, and Me ........................................................ A-4
Selecting Windows’ Internet Access Method .......................................................... A-6
Verifying TCP/IP Properties .................................................................................... A-6
Configuring Windows NT4, 2000 or XP for IP Networking ............................................ A-7
Install or Verify Windows Networking Components ................................................. A-7
DHCP Configuration of TCP/IP in Windows XP, 2000, or NT4 ............................... A-8
DHCP Configuration of TCP/IP in Windows XP ..................................................... A-8
DHCP Configuration of TCP/IP in Windows 2000 .................................................A-11
DHCP Configuration of TCP/IP in Windows NT4 .................................................. A-14
Verifying TCP/IP Properties for Windows XP, 2000, and NT4 .............................. A-16
Configuring the Macintosh for TCP/IP Networking ...................................................... A-17
MacOS 8.6 or 9.x .................................................................................................. A-17
MacOS X ............................................................................................................... A-18
Verifying TCP/IP Properties for Macintosh Computers ......................................... A-18
Verifying the Readiness of Your Internet Account ....................................................... A-19
Are Login Protocols Used? ................................................................................... A-19
What Is Your Configuration Information? .............................................................. A-19

Contents v
Obtaining ISP Configuration Information for Windows Computers ....................... A-20
Obtaining ISP Configuration Information for Macintosh Computers ..................... A-21
Restarting the Network ................................................................................................ A-22
Glossary...............................................................................................................................1-1

vi Contents

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
About This Manual 1-1
Chapter 1
About This Manual
Congratulations on your purchase of the CG814WG Wireless Cable Modem Gateway. The
CG814WG provides connection for multiple personal computers to the Internet. It connects
directly to your cable line using an embedded DOCSIS 2.0 cable modem.
Audience, Conventions, Publication Date
This reference manual assumes that the reader has basic-to-intermediate computer and Internet
skills. However, basic computer network, Internet, firewall, and networking technology tutorial
information is provided in the Appendices.
This guide uses the following typographical conventions:
This guide uses the following formats to highlight special messages:
This manual is written f according to these specifications.:
Table 1. Typographical conventions
italics Emphasis, books, CDs, URL names
bold times roman User input
courier font Screen text, file and server names, extensions, commands, IP addresses
Note: This format is used to highlight information of importance or special interest.
Table 1-1. Firmware Version and Manual Publication Date
Firmware Version 2.95r09
Manual Publication Date April 2004

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
1-2 About This Manual

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
Introduction 2-1
Chapter 2
Introduction
This chapter describes the features of the NETGEAR CG814WG Wireless Cable Modem
Gateway.
About the CG814WG
The NETGEAR CG814WG Wireless Cable Modem Gateway connects directly to the wide area
network (WAN) using its built-in cable modem. It has multiple options to connect to your local
area network (LAN), including a 4-port 10/100 Mbps Ethernet switch, a USB port and an 802.11b
wireless Access Point.
The CG814WG Gateway is a complete security solution that protects your network from attacks
and intrusions. Unlike simple Internet sharing routers that rely on Network Address Translation
(NAT) for security, the CG814WG uses Stateful Packet Inspection for Denial of Service (DoS)
attack protection and intrusion detection. The CG814WG provides highly reliable Internet access
for up to 253 users.
Key Features
The CG814WG offers the following features.
Built-in Cable Modem
The CG814W Gateway connects directly the WAN using an integrated cable modem. The modem
is DOCSIS 2.0, guaranteeing that it will work with your local cable service provider.

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
2-2 Introduction
A Powerful, True Firewall
Unlike simple Internet sharing NAT routers, the CG814WG is a true firewall, using stateful packet
inspection to defend against hacker attacks. Its firewall features include:
• Denial of Service (DoS) protection
Automatically detects and thwarts Denial of Service (DoS) attacks such as Ping of Death,
SYN Flood, LAND Attack and IP Spoofing.
• Configurable Port Forwarding, Port Blocking, Port Triggering and DMZ provide enough
flexibility for most applications.
• Blocks access from your LAN to Internet locations or services that you specify as off-limits.
• Logs security incidents
The CG814WG will log security events such as blocked incoming traffic, port scans, attacks,
and administrator logins. You can configure the gateway to email the log to you whenever a
significant event occurs.
Content Filtering
With its content filtering feature, the CG814WG prevents objectionable content from reaching
your PCs. The gateway allows you to control access to Internet content by screening for keywords
within Web addresses.
Dual login allows an adult to configure content filtering, while still allowing a child to configure
other features of the Gateway.
802.11b and 802.11g Standards-based Wireless Networking
The CG814WG Gateway includes an 802.11g- and 802.11b-compliant wireless access point,
providing continuous, high-speed 54 Mbps access between your wireless and Ethernet devices.
The access point provides:
• 802.11g Standards-based wireless networking at up to 54Mbps
• 64-bit and 128-bit WEP encryption security
• WEP keys can be generated manually or by passphrase
• Wireless access can be restricted by MAC address.

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
Introduction 2-3
Configurable Auto Uplink™ Ethernet Connection
With its internal 4-port 10/100 switch, the CG814WG can connect to either a 10 Mbps standard
Ethernet network or a 100 Mbps Fast Ethernet network. Both the local LAN and the Internet WAN
interfaces are autosensing and capable of full-duplex or half-duplex operation.
The gateway incorporates Auto UplinkTM technology. Each LOCAL Ethernet port will
automatically sense whether the Ethernet cable plugged into the port should have a ‘normal’
connection such as to a PC or an ‘uplink’ connection such as to a switch or hub. That port will then
configure itself to the correct configuration. This feature also eliminates the need to worry about
crossover cables, as Auto Uplink will accommodate either type of cable to make the right
connection.
USB Port
A USB connection for your computer eliminates the need for installing an Ethernet card.
Protocol Support
The CG814WG supports the Transmission Control Protocol/Internet Protocol (TCP/IP).
Appendix B, "Networks, Routing, and Firewall Basics" provides further information on TCP/IP.
• IP Address Sharing by NAT
The CG814WG allows several networked PCs to share an Internet account using only a single
IP address, which may be statically or dynamically assigned by your Internet service provider
(ISP). This technique, known as Network Address Translation (NAT), allows the use of an
inexpensive single-user ISP account.
• Automatic Configuration of Attached PCs by DHCP
The CG814WG dynamically assigns network configuration information, including
IP, gateway, and domain name server (DNS) addresses, to attached PCs on the LAN using the
Dynamic Host Configuration Protocol (DHCP). This feature greatly simplifies configuration
of PCs on your local network.
Easy Installation and Management
You can install, configure, and operate the CG814WG within minutes after connecting it to the
network. The following features simplify installation and management tasks:

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
2-4 Introduction
• Browser-based management
Browser-based configuration allows you to easily configure your gateway from almost any
type of personal computer, such as Windows, Macintosh, or Linux. A user-friendly Setup
Wizard is provided and online help documentation is built into the browser-based Web
Management Interface.
• Diagnostic functions
The gateway incorporates built-in diagnostic functions such as Ping, DNS lookup, and remote
reboot. These functions allow you to test Internet connectivity and reboot the gateway. You
can use these diagnostic functions directly from the CG814WG when your are connect on the
LAN or when you are connected over the Internet via the remote management function.
• Visual monitoring
The gateway’s front panel LEDs provide an easy way to monitor its status and activity.

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
Introduction 2-5
What’s in the Box?
The product package should contain the following items:
• CG814WG Wireless Cable Modem Gateway
• AC power adapter
• Category 5 (CAT5) Ethernet cable
• USB cable
•Resource CD, including:
— This manual
— Application Notes, Tools, and other helpful information
If any of the parts are incorrect, missing, or damaged, contact your NETGEAR dealer. Keep the
carton, including the original packing materials, in case you need to return the product for repair.
The Gateway’s Front Panel
The front panel of the CG814WG (Figure 2-1) contains status LEDs.
Figure 2-1: CG814WG Front Panel
You can use some of the LEDs to verify connections. Table 2-1 lists and describes each LED on
the front panel of the CG814WG Gateway. These LEDs are green when lit.

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
2-6 Introduction
Table 2-1. LED Descriptions
Label Activity Description
Power On
Off
Power is supplied to the gateway.
Power is not supplied to the gateway.
Test On
Off
A system failure has occurred. Reboot the gateway.
Normal operation.
Cable Link On (Green)
Off
Configuration of the cable interface by your cable service provider
is complete.
Configuration of the cable interface is still in progress.
Upload
Traffic
Off
Blink
Data is being transmitted to the cable interface.
The cable interface is idle.
Download
Traffic
Off
Blink
Data is being received from the cable interface.
The cable interface is idle.
Wireless On
Blink
Indicates that the wireless Access Point is operating normally.
Data is being transmitted or received on the wireless interface.
Local
(Local Area
Network)
On (Green)
Blink (Green)
On (Yellow)
Blink (Yellow)
Off
The Local port has detected link with a 100 Mbps device.
Data is being transmitted or received at 100 Mbps.
The Local port has detected link with a 10 Mbps device.
Data is being transmitted or received at 10 Mbps.
No link is detected on this port.
USB On (Green)
Blink (Green)
Off
The Local port has detected link with a USB device.
Data is being transmitted or received through USB.
No link is detected on the USB port.

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
Introduction 2-7
The Gateway’s Rear Panel
The rear panel of the CG814WG (Figure 2-2) contains the connections identified below.
Figure 2-2: CG814WG Rear Panel
Viewed from left to right, the rear panel contains the following elements:
• 802.11 Wireless antenna
• AC power adapter input
• Factory Default Reset push button
• USB port for connecting the gateway to a local computer
• Four Ethernet RJ-45 ports for connecting the gateway to local computers
• Coaxial F-type connector for connecting the gateway to your cable service provider

Reference Manual for the Model CG814WG Wireless Cable Modem Gateway
2-8 Introduction