Netgear Router WGT624 V3 User Manual

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2.If not already selected, select Built-in Ethernet in the Configure list.
3.If not already selected, Select Using DHCP in the TCP/IP tab.
4.Click Save.
Verifying TCP/IP Properties for Macintosh Computers
After your Macintosh is configured and has rebooted, you can check the TCP/IP configuration by 
returning to the TCP/IP Control Panel. From the Apple menu, select Control Panels, then TCP/IP.
The panel is updated to show your settings, which should match the values below if you are using 
the default TCP/IP settings that NETGEAR recommends:
• The IP Address is between 192.168.1.2 and 192.168.1.254
• The Subnet mask is 255.255.255.0
• The Router address is 192.168.1.1
If you do not see these values, you may need to restart your Macintosh or you may need to switch 
the “Configure” setting to a different option, then back again to “Using DHCP Server”. 
						

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Verifying the Readiness of Your Internet Account
For broadband access to the Internet, you need to contract with an Internet service provider (ISP) 
for a single-user Internet access account using a cable modem or DSL modem. This modem must 
be a separate physical box (not a card) and must provide an Ethernet port intended for connection 
to a Network Interface Card (NIC) in a computer. Your firewall does not support a USB-connected 
broadband modem.
For a single-user Internet account, your ISP supplies TCP/IP configuration information for one 
computer. With a typical account, much of the configuration information is dynamically assigned 
when your PC is first booted up while connected to the ISP, and you will not need to know that 
dynamic information. 
In order to share the Internet connection among several computers, your firewall takes the place of 
the single PC, and you need to configure it with the TCP/IP information that the single PC would 
normally use. When the firewall’s Internet port is connected to the broadband modem, the firewall 
appears to be a single PC to the ISP. The firewall then allows the PCs on the local network to 
masquerade as the single PC to access the Internet through the broadband modem. The method 
used by the firewall to accomplish this is called Network Address Translation (NAT) or IP 
masquerading.
Are Login Protocols Used?
Some ISPs require a special login protocol, in which you must enter a login name and password in 
order to access the Internet. If you normally log in to your Internet account by running a program 
such as WinPOET or EnterNet, then your account uses PPP over Ethernet (PPPoE). 
When you configure your router, you will need to enter your login name and password in the 
router’s configuration menus. After your network and firewall are configured, the firewall will 
perform the login task when needed, and you will no longer need to run the login program from 
your PC. It is not necessary to uninstall the login program.
What Is Your Configuration Information?
More and more, ISPs are dynamically assigning configuration information. However, if your ISP 
does not dynamically assign configuration information but instead used fixed configurations, your 
ISP should have given you the following basic information for your account:  
						

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• An IP address and subnet mask
• A gateway IP address, which is the address of the ISP’s router
• One or more domain name server (DNS) IP addresses
• Host name and domain suffix
For example, your account’s full server names may look like this:
mail.xxx.yyy.com 
In this example, the domain suffix is 
xxx.yyy.com.
If any of these items are dynamically supplied by the ISP, your firewall automatically acquires 
them.
If an ISP technician configured your PC during the installation of the broadband modem, or if you 
configured it using instructions provided by your ISP, you need to copy the configuration 
information from your PC’s Network TCP/IP Properties window or Macintosh TCP/IP Control 
Panel before reconfiguring your PC for use with the firewall. These procedures are described next.
Obtaining ISP Configuration Information for Windows Computers
As mentioned above, you may need to collect configuration information from your PC so that you 
can use this information when you configure the WGT624 v3 wireless router. Following this 
procedure is only necessary when your ISP does not dynamically supply the account information. 
To get the information you need to configure the firewall for Internet access:
1.On the Windows taskbar, click the Start button, point to Settings, and then click Control Panel.
2.Double-click the Network icon.
The Network window opens, which displays a list of installed components.
3.Select TCP/IP, and then click Properties.
The TCP/IP Properties dialog box opens.
4.Select the IP Address tab.
If an IP address and subnet mask are shown, write down the information. If an address is 
present, your account uses a fixed (static) IP address. If no address is present, your account 
uses a dynamically-assigned IP address. Click “Obtain an IP address automatically”.
5.Select the Gateway tab. 
						

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If an IP address appears under Installed Gateways, write down the address. This is the ISP’s 
gateway address. Select the address and then click Remove to remove the gateway address.
6.Select the DNS Configuration tab.
If any DNS server addresses are shown, write down the addresses. If any information appears 
in the Host or Domain information box, write it down. Click Disable DNS.
7.Click OK to save your changes and close the TCP/IP Properties dialog box.
You are returned to the Network window.
8.Click OK.
9.Reboot your PC at the prompt. You may also be prompted to insert your Windows CD.
Obtaining ISP Configuration Information for Macintosh 
Computers
As mentioned above, you may need to collect configuration information from your Macintosh so 
that you can use this information when you configure the WGT624 v3 wireless router. Following 
this procedure is only necessary when your ISP does not dynamically supply the account 
information. 
To get the information you need to configure the firewall for Internet access:
1.From the Apple menu, select Control Panels, then TCP/IP.
The TCP/IP Control Panel opens, which displays a list of configuration settings. If the 
“Configure” setting is “Using DHCP Server”, your account uses a dynamically-assigned IP 
address. In this case, close the Control Panel and skip the rest of this section.
2.If an IP address and subnet mask are shown, write down the information. 
3.If an IP address appears under Router address, write down the address. This is the ISP’s 
gateway address.
4.If any Name Server addresses are shown, write down the addresses. These are your ISP’s DNS 
addresses.
5.If any information appears in the Search domains information box, write it down.
6.Change the “Configure” setting to “Using DHCP Server”.
7.Close the TCP/IP Control Panel. 
						

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Restarting the Network
Once you’ve set up your computers to work with the firewall, you must reset the network for the 
devices to be able to communicate correctly. Restart any computer that is connected to the firewall.
After configuring all of your computers for TCP/IP networking and restarting them, and 
connecting them to the local network of your WGT624 v3 wireless router, you are ready to access 
and configure the firewall. 
						

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Appendix D
Wireless Networking Basics
This chapter provides an overview of Wireless networking.
Wireless Networking Overview
The WGT624 v3 wireless router conforms to the Institute of Electrical and Electronics Engineers 
(IEEE) 802.11b and 802.11g standards for wireless LANs (WLANs). On an 802.11b or g wireless 
link, data is encoded using direct-sequence spread-spectrum (DSSS) technology and is transmitted 
in the unlicensed radio spectrum at 2.5GHz. The maximum data rate for the 802.11b wireless link 
is 11 Mbps, but it will automatically back down from 11 Mbps to 5.5, 2, and 1 Mbps when the 
radio signal is weak or when interference is detected. The 802.11g auto rate sensing rates are 1, 2, 
5.5, 6, 9, 12, 18, 24, 36, 48, and 54 Mbps. 
The 802.11 standard is also called Wireless Ethernet or Wi-Fi by the Wireless Ethernet 
Compatibility Alliance (WECA, see http://www.wi-fi.net), an industry standard group promoting 
interoperability among 802.11 devices. The 802.11 standard offers two methods for configuring a 
wireless network - ad hoc and infrastructure.
Infrastructure Mode
With a wireless Access Point, you can operate the wireless LAN in the infrastructure mode. This 
mode provides wireless connectivity to multiple wireless network devices within a fixed range or 
area of coverage, interacting with wireless nodes via an antenna. 
In the infrastructure mode, the wireless access point converts airwave data into wired Ethernet 
data, acting as a bridge between the wired LAN and wireless clients. Connecting multiple Access 
Points via a wired Ethernet backbone can further extend the wireless network coverage. As a 
mobile computing device moves out of the range of one access point, it moves into the range of 
another. As a result, wireless clients can freely roam from one Access Point domain to another and 
still maintain seamless network connection. 
						

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Ad Hoc Mode (Peer-to-Peer Workgroup)
In an ad hoc network, computers are brought together as needed; thus, there is no structure or fixed 
points to the network - each node can generally communicate with any other node. There is no 
Access Point involved in this configuration. This mode enables you to quickly set up a small 
wireless workgroup and allows workgroup members to exchange data or share printers as 
supported by Microsoft networking in the various Windows operating systems. Some vendors also 
refer to ad hoc networking as peer-to-peer group networking.
In this configuration, network packets are directly sent and received by the intended transmitting 
and receiving stations. As long as the stations are within range of one another, this is the easiest 
and least expensive way to set up a wireless network. 
Network Name: Extended Service Set Identification (ESSID)
The Extended Service Set Identification (ESSID) is one of two types of Service Set Identification 
(SSID). In an ad hoc wireless network with no access points, the Basic Service Set Identification 
(BSSID) is used. In an infrastructure wireless network that includes an access point, the ESSID is 
used, but may still be referred to as SSID.
An SSID is a thirty-two character (maximum) alphanumeric key identifying the name of the 
wireless local area network. Some vendors refer to the SSID as network name. For the wireless 
devices in a network to communicate with each other, all devices must be configured with the 
same SSID.
The ESSID is usually broadcast in the air from an access point. The wireless station sometimes can 
be configured with the ESSID ANY. This means the wireless station will try to associate with 
whichever access point has the stronger radio frequency (RF) signal, providing that both the access 
point and wireless station use Open System authentication.
Authentication and WEP Data Encryption
The absence of a physical connection between nodes makes the wireless links vulnerable to 
eavesdropping and information theft. To provide a certain level of security, the IEEE 802.11 
standard has defined these two types of authentication methods:
•Open System. With Open System authentication, a wireless computer can join any network 
and receive any messages that are not encrypted.  
						

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•Shared Key. With Shared Key authentication, only those PCs that possess the correct 
authentication key can join the network. By default, IEEE 802.11 wireless devices operate in 
an Open System network. 
Wired Equivalent Privacy (WEP) data encryption is used when the wireless devices are configured 
to operate in Shared Key authentication mode. 
802.11 Authentication
The 802.11 standard defines several services that govern how two 802.11 devices communicate. 
The following events must occur before an 802.11 Station can communicate with an Ethernet 
network through an access point, such as the one built in to the WGT624 v3:
1.Turn on the wireless station.
2.The station listens for messages from any access points that are in range.
3.The station finds a message from an access point that has a matching SSID.
4.The station sends an authentication request to the access point.
5.The access point authenticates the station.
6.The station sends an association request to the access point.
7.The access point associates with the station.
8.The station can now communicate with the Ethernet network through the access point.
An access point must authenticate a station before the station can associate with the access point or 
communicate with the network. The IEEE 802.11 standard defines two types of authentication: 
Open System and Shared Key.
• Open System Authentication allows any device to join the network, assuming that the device 
SSID matches the access point SSID. Alternatively, the device can use the “ANY” SSID 
option to associate with any available Access Point within range, regardless of its SSID. 
• Shared Key Authentication requires that the station and the access point have the same WEP 
Key to authenticate. These two authentication procedures are described below.
Open System Authentication
The following steps occur when two devices use Open System Authentication:
1.The station sends an authentication request to the access point. 
						

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2.The access point authenticates the station.
3.The station associates with the access point and joins the network.
This process is illustrated below.
Figure 7-4:  Open system authentication
Shared Key Authentication
The following steps occur when two devices use Shared Key Authentication:
1.The station sends an authentication request to the access point.
2.The access point sends challenge text to the station.
3.The station uses its configured 64-bit or 128-bit default key to encrypt the challenge text, and 
sends the encrypted text to the access point.
4.The access point decrypts the encrypted text using its configured WEP Key that corresponds 
to the station’s default key. The access point compares the decrypted text with the original 
challenge text. If the decrypted text matches the original challenge text, then the access point 
and the station share the same WEP Key and the access point authenticates the station. 
5.The station connects to the network.
If the decrypted text does not match the original challenge text (the access point and station do not 
share the same WEP Key), then the access point will refuse to authenticate the station and the 
station will be unable to communicate with either the 802.11 network or Ethernet network.
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