Linksys WRT51AB Users Manual

Dual-Band Wireless A+B Broadband Router

DTIM Interval This value, between 1 and 16384, indicates the interval of the Delivery Traffic Indication Message (DTIM). A DTIM field is a countdown field infor ming clients of the next window for listening to broadcast and multicast messages. When the Router has buffered broadcast or multicast messages for associated clients, it sends the next DTIM with a DTIM Interval value. Its clients hear the beacons and awak en to receiv e the broadcast and multicast messages. The default value is 1.

RTS Threshold Should you encounter inconsistent data flow, only minor reduction of the default value, 2346, is recommended. If a network packet is smaller than the preset RTS threshold size, the RTS/CTS mechanism will not be enabled. The Router sends Request to Send (RTS) frames to a particular receiving station and negotiates the sending of a data frame. After receiving an RTS, the wireless station responds with a Clear to Send (CTS) frame to acknowledge the right to begin transmission. The RTS Threshold value should remain at its default value of 2346.

Fragmentation Thr eshold This value specifies the maximum size for a packet before data is fragmented into multiple packets. If you experience a high packet error rate, you may slightly increase the Fragmentation Threshold. Setting the Fragmentation Threshold too low may result in poor network performance. Only minor reduction of the default value is recommended. In most cases, it should remain at its default value of 2346.

Transmission Rate The rate of data transmission should be set depending on the speed of your wireless network. You can select from a range of transmission speeds (6, 9, 12, 18, 24, 36, 48, or 54Mbps), or you can select Best to have the Router automatically use the fastest possible data rate and enable the AutoFallback feature. Auto-Fallback will negotiate the best possible connection speed between the Router and a wireless client. The def ault value is Best.

Transmit Power The greater the transmit power used, the larger the area a wireless network co v ers. To minimize the likelihood of ea v esdropping b y unauthorized wireless users, do not use more transmit pow er than necessary to co ver the range needed for your wireless network. Try using the Router at different levels of transmit power, and determine how much transmit power is needed to reach the wireless client, such as a PC, or access point that is farthest from the Router. Then select the appropriate level of transmit power (Full, Half, Quarter, Eighth, or Min) from the drop-down menu. The default value is Full.

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The Advanced Wireless screen allows you to customize data transmission settings and access the 802.1x Configuration screen. In most cases, the advanced wireless settings on this screen should remain at their default values.

5GHz, 802.11a

Beacon Interval The Beacon Interval value indicates the frequency interval of

the beacon. Enter a value between 20 and 1000. A beacon is a packet broadcast by the Router to synchronize the wireless network. The default value is 100.

Advanced Wireless

Figure 6-19

Dual-Band Wireless A+B Broadband Router

802.1x Configuration

The 802.1x Configuration screen allows you to alter the 802.1x settings for your wireless network(s). Based on the Extensible Authentication Protocol (EAP), the 802.1x standard specifies an authentication framework for a wireless client to access a network, so network security is enhanced.

To access a network with 802.1x enabled, wireless clients, such as PCs, must use 802.1x client software or Windows XP, which supports 802.1x.

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2.4GHz, 802.11b

Beacon Interval The Beacon Interval value indicates the frequency interval of

the beacon. Enter a value between 20 and 1000. A beacon is a packet broadcast by the Router to synchronize the wireless network. The default value is 100.

Fragmentation Thr eshold This value specifies the maximum size for a packet before data is fragmented into multiple packets. If you experience a high packet error rate, you may slightly increase the Fragmentation Threshold. Setting the Fragmentation Threshold too low may result in poor network performance. Only minor reduction of this value is recommended. In most cases, it should remain at its default value of 2346.

Preamble Type The preamble defines the length of the CRC block for communication between the Router and a roaming wireless network adapter. Select the appropriate preamble type for your wireless network. (High network traffic areas should use the shorter preamble type.) The default is Long Preamble.

Transmission Rate The rate of data transmission should be set depending on the speed of your wireless network. You can select from a range of transmission speeds (1, 2, 5.5, or 11Mbps), or you can select Best to have the Router automatically use the fastest possible data rate and enable the Auto-Fallback feature. Auto-Fallback will negotiate the best possible connection speed between the Router and a wireless client. The default setting is Best.

T o appl y an y of the settings y ou change on this page, click the Apply button. To cancel any changes you’ve entered on this page, click the Cancel button. To get more information about the features, click the Help button.

802.1x Configuration

802.1x Configuration Click the 802.1x Configuration button to customize

the Router’s 802.1x feature (see Figure 6-20).

Figure 6-20

Note: If your wireless network does not have a RADIUS server, the

802.1x feature is not applicable to your network. (802.1x is an advanced data security measure and not essential for router operation.)

Note: For more details about 802.1x, refer to “Appendix C: Configuring Wireless Security.”

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RADIUS Server

The Router’s 802.1x feature works with a RADIUS server . It may also work with other types of authentication servers, depending on the specifics of each authentication server.

RADIUS Server IP Address Enter the IP Address of the RADIUS server in the field provided.

RADIUS Server Port Enter the Port Number of the RADIUS server in the field provided. The default is 1812.

Shared Secret Enter the Shared Secret Key used by the Router and RADIUS server during the authentication process.

5GHz, 802.11a

Disable/EAP-MD5/EAP-TLS/TTLS Select EAP-MD5 to enable use of

802.1x with MD5 authentication for the 5GHz, 802.11a network connection between a wireless client and a RADIUS server (the Router acts as an authenticator). Select EAP-TLS/TTLS to enable use of 802.1x with TLS or TTLS authentication for the 5GHz, 802.11a network connection between a wireless client and a RADIUS server (the Router acts as an authenticator). To disable 802.1x authentication for your 5GHz, 802.11a network, keep the default setting, Disable.

WEP Settings If you are using 802.1x with MD5 authentication, then you must click the WEP Settings button and set up a static key for WEP encryption. This static key must be set on the Router’s 5GHz, 802.11a WEP Settings screen and on all 5GHz, 802.11a wireless clients.

Dynamic WEP K ey Length When 5GHz, 802.11a wireless clients are using certif icate-based authentication (EAP-TLS or EAP-TTLS), dynamic WEP keys are automatically generated. Select the length of the Dynamic Key (64 or 128-bit) from the drop-down menu.

Key Renewal Timeout If you are using dynamic WEP keys (available only for EAP-TLS or EAP-TTLS authentication), enter the number of seconds that will elapse before the Dynamic Key automatically changes. The default is 300 seconds.

Port Inactivity T imeout After the wireless client has been authenticated , the Router monitors activity on the port being used. In the Port Inactivity Timeout f ield, enter the number of seconds the port can be inactive before the client automatically forced to reauthenticate. The default is 600seconds.

Port Connectivity Timeout After the Router requests the identity of a wireless client, the client must respond with an identity message within a certain length of time. In the Port Connectivity Timeout field, enter the number of seconds the client has to respond within before the connection is terminated. The default is 300 seconds.

2.4GHz, 802.11b

Disable/EAP-MD5/EAP-TLS/TTLS Select EAP-MD5 to enable use of

802.1x with MD5 authentication for the 2.4GHz, 802.11b network connection between a wireless client and a RADIUS server (the Router acts as an authenticator). Select EAP-TLS/TTLS to enable use of 802.1x with TLS or TTLS authentication for the 2.4GHz, 802.11b network connection between a wireless client and a RADIUS server (the Router acts as an authenticator). To disable 802.1x authentication for your 2.4GHz, 802.11b network, keep the default setting, Disable

WEP Settings If you are using 802.1x with MD5 authentication, then you must click the WEP Settings button and set up a static key for WEP encryption. This static key must be set on the Router’s 2.4GHz, 802.11b WEP Settings screen and on all 2.4GHz, 802.11b wireless clients.

Note: Using MD5 authentication is less secure than using certificatebased authentication (TLS or TTLS), because keys are not changed automatically.

Important: The Router’s 802.1x feature works with Windows XP. It may also work with other Windows operating systems, depending on the specifics of your PC’s operating system and the 802.1x client software being used.

Note: Many authentication methods work within the 802.1x framework. The Router supports MD5 and certificate-based (TLS or TTLS) authentication methods. Using MD5 authentication is less secure than using certif icate-based authentication (TLS or TTLS), because keys are not changed automatically.

Dual-Band Wireless A+B Broadband Router

The Filters screen allows you to block specific internal users from accessing the Internet. You can set up filters by using MAC addresses, IP addresses, or network port numbers (or a range of ports).

Filtered Private Port Range To f ilter users by network port number, select Both, TCP, or UDP, depending on which protocols you want to filter. Then

enter the port numbers you want to filter into the port number f ields. Users connected to the Router will no longer be able to access any port number listed there. To disable a filter, select Disable.

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Dynamic WEP Key Length When 2.4GHz, 802.11b wireless clients are using certif icate-based authentication (EAP-TLS or EAP-TTLS), dynamic WEP keys are automatically generated. Select the length of the Dynamic Key (64 or 128-bit) from the drop-down menu.

Filters

Figure 6-21

Dual-Band Wireless A+B Broadband Router

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If you want to enter more than ten MAC addresses, select MAC Addresses 110, 11-20, 21-30, 31-40, or 41-50 from the drop-down menu to enter addition-

al MAC addresses, up to a maximum of 50. Then click the Applybutton to sav e the MAC addresses.

To disable Private MAC Filtering, select Disable.

Block WAN Request By enabling the Block WAN Request feature, you can prevent your network from being “pinged,” or detected, by other Internet users. The Block WAN Request feature also reinforces your network security by hiding network ports. Both functions of the Block WAN Request feature make it more difficult for outside users to work their way into your network. The default is Enable.

IPSec Pass-Through The Router supports IPSec Pass-Through. Internet Protocol Security (IPSec) is a suite of protocols used to implement secure exchange of packets at the IP layer, and it is one of the methods used to enable Virtual Private Networking (VPN) tunnels. IPSec is more secure than PPTP. The default is Enable.

PPTP Pass-Through The Router supports PPTP Pass-Through. Point-to-Point Tunneling Protocol (PPTP) is one of the methods used to enable VPN tunnels. PPTP is less secure than IPSec. The default is Enable.

Remote Management This feature allows you to manage the Router from a remote location, via the Internet. To enable this feature, select Enable, and use the specified port (default is 8080) on your PC to remotely manage the Router. The default is Disable.

MTU MTU is the Maximum Transmission Unit. It specif ies the largest packet size permitted for network transmission. To use this feature, select Enable, and enter the value desired. You should leave this value in the 572 to 1492 range. The default is Disable.

Private IP Filter To set up a filter using IP addresses, select Enable. Then select Only Allow Internet

Access for the IP Addresses on the List or Only Deny Internet Access for the IP Addresses on the List.

Click the Edit IP Filter List button. Enter the appropriate IP addresses into the IP address fields (see Figure 6-22). Each IP address should be entered in this format: xxx.xxx.xxx.xxx (the x’s represent the actual digits of the IP address).

If you want to enter more than ten IP addresses, select IP Addresses 1-10, 11-20, 21-30, 31-40, or 41-50 from the drop-down menu to enter additional IP addresses, up to a maximum of 50. Then click the Applybutton to save the IP addresses.

To disable Private IP Filtering, select Disable.

Private MAC Filter To set up a f ilter using MAC addresses, select Enable. Then select Only Allow Internet

Access for the MAC Addresses on the List or Only Deny Internet Access for the IP Addresses on the List.

Click the Edit MAC Filter List button. Enter the appropriate MAC addresses into the MAC address fields (see Figure 6-23). Each MAC address should be entered in this format: xx:xx:xx:xx:xx:xx (the x’s represent the actual characters of the MAC address).

Figure 6-22

Figure 6-23

Dual-Band Wireless A+B Broadband Router

TCP Protocol Click this checkbox if you want to forward the data transmissions that use the TCP protocol.

UDP Protocol Click this checkbox if you want to forward the data transmissions that use the UDP protocol.

IP Address For each application, enter the IP Address of the PC running the specific application.

Enable Click the Enable checkbox to enable port forwarding for the relevant application.

The following table shows the typical port forwarding settings for common Internet applications.

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FTP

Applications External Port TCP Protocol UDP Protocol

Telnet 23

SMTP 25

DNS 53

TFTP 69

Finger 79

HTTP 80

POP3 110

NNTP 119

SNMP 161

The Port Forwarding screen sets up public services on your network, such as web servers, ftp servers, e-mail servers, or other specialized Internet applications. (Specialized Internet applications are any applications that use Internet access to perform functions such as videoconferencing or online gaming. Some Internet applications may not require any forwarding.)

Customized Applications In the f ield provided, enter the name you wish to give each application.

External Port For each application, enter the number of the External Ports (the port numbers seen by users on the Internet) in the appropriate f ields. (To find out the por t range, check your application’s documentation.) If there is only one External Port, enter its number in both External Port fields.

Port Forwarding

Figure 6-24

Note: Any PC whose port is being forwarded should have its DHCP client function disabled and a new static IP address assigned to it because its IP address may change when using the DHCP function.

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2. If you selected the Gateway mode, click the Apply button. If you selected

the Router mode, proceed to step 3.

3. For Dynamic Routing, the default is Enable. The Dynamic Routing feature

enables the Router to automatically adjust to physical changes in the network’s layout and exchange routing tables with the other router(s). The Router determines the network packets’ route based on the fewest number of hops between the source and the destination. Select Disable to disable the Dynamic Routing feature for data transmissions.

4. To set up a static route between the Router and another network, select a number from the Static Routing drop-down list. (A static route is a predetermined pathway that network information must travel to reach a specific host or network.)

5. Enter the following data:

• Destination LAN IP - The Destination LAN IP is the address of the

remote network or host to which you want to assign a static route.

• Subnet Mask - The Subnet Mask determines which portion of a

Destination LAN IP address is the network portion, and which portion is the host portion.

• Default Gateway - This is the IP address of the gateway device that

allows for contact between the Router and the remote network or host.

6. To cancel your changes, click the Cancel button. To save your changes,

click the Apply button. To get more information about the features, click the Help button.

To delete a static route entry:

1. From the Static Routing drop-down list, select the entry number of the stat-

ic route.

2. Click the Delete This Entry button.

3. To cancel a deletion, click the Cancel button. To save a deletion, click the

Apply button. To get more information about the features, click the Help button.

On the Routing screen, you can set the routing mode of the Router. Gateway mode is recommended for most users.

To set up routing:

1. Choose the cor rect working mode. Select Gateway if the Router is hosting

your network’s connection to the Internet (recommended for most users). Select Router if the Router exists on a network with other routers.

Routing

Figure 6-25

Note: The Routing screen and available features will var y depending on which mode you select.

Note: If you have more than one router on your network, you should select Router for the working mode.

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The DMZ Host screen lets you enable the DMZ hosting feature, which allows one local user to be exposed to the Internet for use of a special-purpose service such as Internet gaming or videoconferencing. Whereas port forwarding can only forward a maximum of ten port ranges, DMZ hosting forwards all the ports to one PC simultaneously. It is recommended to use Port Forwarding whenever possible because it is more secure.

To expose one PC to the Internet:

1. Click the Enable radio button.

2. Enter the computer’s IP address in the DMZ Host IP Address f ield.

3. T o cancel y our changes, click the Cancelbutton.T o sa ve y our ne w settings,

click the Apply button. To get more information about the features, click the Help button.

Note: Any PC whose ports are being forwarded should have its DHCP client function disabled and a new static IP address assigned to it because its IP address may change when using the DHCP client function.

DMZ Host

Figure 6-27

Show Routing Table Click the Show Routing Table button to view all of the valid dynamic and static route entries in use (see Figure 6-26). The Destination LAN IP address, Subnet Mask, Gateway, and Interface information are displayed for each entry. Click the Refresh button to display the most up-to-date data.

Figure 6-26

Dual-Band Wireless A+B Broadband Router

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If you do not know your adapter’s MAC address, follow these instructions:

1. Click the Start button, and select Run.

2. Enter command in the f ield provided, and press the OK button.

3. At the command prompt, enter ipconfig /all. Then press the Enter key.

4. Write down your adapter’s physical address; it is the adapter’s MAC address.

On the MAC Address Clone screen, you can clone the MAC address of your PC’s network adapter onto the Router.

A MAC address is a 12-digit code assigned to a unique piece of hardware for identification, like a social security number. Some ISPs require that you register the MAC address of your PC’s network adapter, which was connected to your cable or DSL modem during installation. To avoid calling your ISP and changing the MAC address that is registered with the ISP, follow these instructions:

1. Click the Enable radio button.

2. Enter your adapter’s MAC address in the User Defined Internet MAC Address field.

3. T o cancel your changes, click the Cancelbutton.To save your new settings, click the Apply button. To get more infor mation about the features, click the Help button.

To disable MAC address cloning, click the Disable radio button.

MAC Address Clone

Figure 6-28

Dual-Band Wireless A+B Broadband Router

For W indo ws 2000:

A. Click Start, Settings, and Control Panel. Double-click Network and

Dial-Up Connections.

B. Right-click the Local Area Connection that is associated with the Ethernet

adapter you are using, and select the Properties option.

C. In the Components checked are used by this connection box, highlight

Internet Protocol (TCP/IP), and click the Properties button. Select Use the following IP address option.

D. Enter a unique IP address that is not used by any other computer on the

network connected to the Router. You can only use an IP address in the ranges 192.168.1.2 to 192.168.1.99 and 192.168.1.151 to 192.168.1.254.

E. Enter the Subnet Mask, 255.255.255.0. F. Enter the Default Gateway, 192.168.1.1 (Router’s default IP address). G. Toward the bottom of the window, select Use the following DNS server

addresses, and enter the Preferred DNS server and Alternative DNS server (provided b y y our ISP). Contact y our ISP or go on its w ebsite to find

the information.

H. Click the OK button in the Internet Protocol (TCP/IP) Properties window,

and click the OK button in the Local Area Connection Properties window.

I. Restar t the computer if asked.

For Windows NT 4.0:

A. Click Start, Settings, and Control Panel. Double-click the Network icon. B. Click the Protocol tab, and double-click TCP/IP Protocol. C. When the window appears, make sure you have selected the correct

Adapter for your Ethernet adapter.

D. Select Specify an IP address, and enter a unique IP address that is not

used by any other computer on the network connected to the Router. You can only use an IP address in the ranges 192.168.1.2 to 192.168.1.99 and

192.168.1.151 to 192.168.1.254.

E. Enter the Subnet Mask, 255.255.255.0. F. Enter the Default Gateway, 192.168.1.1 (Router’s default IP address). G. Click the DNS tab, and enter the Host and Domain names (e.g., John for

Host and home for Domain). Under DNS Service Search Order, click the Add button. Enter the DNS IP address in the DNS Server field, and click the Add button. Repeat this action for all DNS IP addresses given by your ISP.

H. Click the OK button in the TCP/IP Protocol Properties window, and click

the Close button in the Network window.

I. Restar t the computer if asked.

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Appendix A:Troubleshooting

This appendix consists of two parts: “Common Problems and Solutions” and “Frequently Asked Questions.” Pro vided are possib le solutions to problems that may occur during the installation and operation of the Router . Read the descriptions below to help solve y our problems. If y ou can’ t find an answer here, check the Linksys website at www.linksys.com.

1. I need to set a static IP address on a PC.

The Router, by default, assigns an IP address range of 192.168.1.100 to

192.168.1.150 using the DHCP server on the Router. To set a static IP address,

you can only use the ranges 192.168.1.2 to 192.168.1.99 and 192.168.1.151 to

192.168.1.254. Each PC or network device that uses TCP/IP must have a

unique address to identify itself in a network. If the IP address is not unique to a network, Windows will generate an IP conflict error message. You can assign a static IP address to a PC by performing the following steps:

For Windows 98 and Me:

A. Click Start, Settings, and Control Panel. Double-click Network. B. In The following network components are installed box, select the TCP/IP->

associated with your Ethernet adapter. If you only have one Ethernet adapter installed, y ou will onl y see one TCP/IP line with no association to an Ethernet adapter. Highlight it and click the Proper ties button.

C. In the TCP/IP properties window, select the IP address tab, and select

Specify an IP address. Enter a unique IP address that is not used by any other computer on the network connected to the Router. You can only use an IP address in the ranges 192.168.1.2 to 192.168.1.99 and 192.168.1.151 to 192.168.1.254. Make sure that each IP address is unique for each PC or network device.

D. Click the Gatewa y tab, and in the Ne w Gateway prompt, enter 192.168.1.1,

which is the default IP address of the Router. Click the Addbutton to accept the entry.

E. Click the DNS tab, and make sure the DNS Enabled option is selected.

Enter the Host and Domain names (e.g., John for Host and home for Domain). Enter the DNS entry provided by your ISP. If your ISP has not provided the DNS IP address, contact your ISP to get that information or go to its website for the information.

F. Click the OK button in the TCP/IP properties window, and click Close or

the OK button for the Network window.

G. Restart the computer when asked.

Common Problems and Solutions

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B. Open a command prompt.

• For Windows 98 and Me, please click Start and Run. In the Open field, type in command. Press the Enter key or click the OK button.

• For Windows NT, 2000, and XP, please click Start and Run. In the Open field, type cmd. Press the Enter key or click the OK button.

C. In the command prompt, type ping 192.168.1.1 and press the Enter key.

• If you get a reply, the computer is communicating with the Router.

• If you do NOT get a reply, please check the cable, and make sure Obtain an IP address automatically is selected in the TCP/IP settings for your Ethernet adapter.

D. In the command prompt, type ping followed by your Internet or WAN IP

address and press the Enter key. The Internet or WAN IP Address can be found on the Status screen of the Router’s web-based utility. For example, if your Internet or WAN IP address is 1.2.3.4, you would enter ping 1.2.3.4 and press the Enter key.

• If you get a reply, the computer is connected to the Router.

• If you do NOT get a reply, try the ping command from a different computer to verify that your original computer is not the cause of the problem.

E. In the command prompt, type ping www.yahoo.com and press the Enter

key.

• If you get a reply, the computer is connected to the Internet. If you cannot open a webpage, try the ping command from a different computer to verify that your original computer is not the cause of the problem.

• If you do NOT get a reply, there may be a problem with the connection. Try the ping command from a different computer to verify that y our original computer is not the cause of the problem.

3. I am not getting an IP address on the Inter net with my Internet connection.

A. Refer to “Problem #2, I want to test my Internet connection” to verify that

you have connectivity.

B. If you need to register the MAC address of your Ethernet adapter with your

ISP, please see “Appendix D: Finding the MAC address and IP Address for Your Ethernet Adapter.” If you need to clone the MAC address of your Ethernet adapter onto the Router, see the MAC Address Clone section of “Chapter 6: The Router’s Web-based Utility” for details.

C. Make sure you are using the right Internet connection settings. Contact your

ISP to see if your Internet connection type is DHCP, Static IP Address, or PPPoE (commonly used by DSL consumers). Please refer to the Setup section of “Chapter 6: The Router’s Web-based Utility” for details on Internet connection settings.

For W indo ws XP:

The following instructions assume you are running Windows XP with the default interface. If you are using the Classic interface (where the icons and menus look like previous Windows versions), please follow the instructions for Windows 2000.

A. Click Start and Control Panel. B. Click the Network and Internet Connections icon and then the Network

Connections icon.

C. Right-click the Local Area Connection that is associated with the Ethernet

adapter you are using, and select the Properties option.

D. In the This connection uses the following items box, highlight Internet

Protocol (TCP/IP). Click the Properties button.

E. Enter a unique IP address that is not used by any other computer on the net-

work connected to the Router. You can only use an IP address in the ranges

192.168.1.2 to 192.168.1.99 and 192.168.1.151 to 192.168.1.254.

F. Enter the Subnet Mask, 255.255.255.0. G. Enter the Default Gateway, 192.168.1.1 (Router’s default IP address). H. Toward the bottom of the window, select Use the following DNS server

addresses, and enter the Preferred DNS server and Alternative DNS server (provided b y y our ISP). Contact y our ISP or go on its w ebsite to find

the information.

I. Click the OK button in the Internet Protocol (TCP/IP) Properties window.

Click the OK button in the Local Area Connection Properties window.

2. I want to test my Internet connection.

A. Check your TCP/IP settings.

For Windows 98, Me, 2000, and XP: Refer to “Chapter 4: Configure the PCs” for details. Make sure Obtain IP

address automatically is selected in the settings.

For Windows NT 4.0:

• Click Start, Settings, and Control Panel. Double-click the Network

icon.

• Click the Protocol tab, and double-click on TCP/IP Protocol.

• When the window appears, make sure you have selected the correct

Adapter for your Ethernet adapter and set it for Obtain an IP address from a DHCP server.

• Click the OK button in the TCP/IP Protocol Properties window, and click the Close button in the Network window.

• Restart the computer if asked.

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of the web interface. If you assigned a static IP address to an y computer or network device on the network, you need to change its IP address accordingly to

192.168.2.Y (Y being any number from 1 to 254). Note that each IP address must be unique within the network.

Your VPN may require port 500/UDP packets to be passed to the computer that is connecting to the IPSec server. Refer to “Problem #7, I need to set up online game hosting or use other Internet applications” for details.

Check the Linksys website for more information at www.linksys.com.

6. I need to set up a server behind my Router.

To use a server like a web, ftp, or mail server, you need to know the respective port numbers they are using. For example, port 80 (HTTP) is used for web; port 21 (FTP) is used for FTP, and port 25 (SMTP outgoing) and port 110 (POP3 incoming) are used for the mail server. You can get more information by viewing the documentation provided with the ser ver you installed. Follow these steps to set up port forwarding through the Router’s web-based utility. We will be setting up web, ftp, and mail servers.

A. Access the Router’s web-based utility by going to http://192.168.1.1 or the

IP address of the Router. Go to the Advanced => Port Forwarding tab. B. Enter any name you want to use for the Customized Application. C. Enter the External Port range of the service you are using. For example,

if you have a web server, you would enter the range 80 to 80. D. Check the protocol you will be using, TCP and/or UDP. E. Enter the IP address of the PC or network device that you want the port

server to go to. For example, if the web server’s Ethernet adapter IP address

is 192.168.1.100, you would enter 100 in the field provided. Check

“Appendix D: Finding the MAC Address and IP Address for Your Ethernet

Adapter” for details on getting an IP address. F. Check the Enableoption for the port services you want to use. Consider the

example below:

Customized External Port TCP UDP IP Address Enable Application Web server 80 to 80 X X 192.168.1.100 X FTP server 21 to 21 X 192.168.1.101 X SMTP (outgoing) 25 to 25 X X 192.168.1.102 X POP3 (incoming) 110 to 110 X X 192.168.1.102 X

When you have completed the configuration, click the Apply button.

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D. Make sure you have the right cable. Check to see if the Internet column has

a solidly lit Link/Act LED.

E. Make sure the cable connecting from your cable or DSL modem is con-

nected to the Router’s Internet port. Verify that the Status page of the Router’s web-based utility shows a valid IP address from your ISP.

F. Turn off the computer, Router, and cable/DSL modem. Wait 30 seconds,

and then turn on the Router, cable/DSL modem, and computer. Check the Status tab of the Router’s web-based utility to see if you get an IP address.

4. I am not able to access the Setup page of the Router’s web-based utility.

A. Refer to “Problem #2, I want to test my Internet connection” to verify that

your computer is properly connected to the Router.

B. Refer to “Appendix D: Finding the MAC Address and IP address for Your

Ethernet Adapter” to verify that your computer has an IP Address, Subnet Mask, Gateway, and DNS.

C. Set a static IP address on your system; refer to “Problem #1: I need to set a

static IP address.”

D. Refer to “Problem #10: I need to remove the proxy settings or the dial-up

pop-up window (for PPPoE users).”

5. I can’t get my Virtual Private Network (VPN) working through the Router.

Access the Router’s web interface by going to http://192.168.1.1 or the IP address of the Router, and go to the Advanced => Filters tab. Make sure you

have IPsec pass-through and/or PPTP pass-through enabled.

VPNs that use IPSec with the ESP (Encapsulation Security Payload known as protocol 50) authentication will work fine. At least one IPSec session will w ork through the Router; however, simultaneous IPSec sessions may be possible, depending on the specifics of your VPNs.

VPNs that use IPSec and AH (Authentication Header known as protocol 51) are incompatible with the Router . AH has limitations due to occasional incompatibility with the NAT standard.

Change the IP address for the Router to another subnet to avoid a conflict between the VPN IP address and your local IP address. For example, if your VPN server assigns an IP address 192.168.1.X (X is a number from 1 to 254) and your local LAN IP address is 192.168.1.X (X is the same number used in the VPN IP address), the Router will have difficulties routing information to the right location. If you change the Router’s IP address to 192.168.2.1, that should solve the problem. Change the Router’s IP address through the Setup tab

Dual-Band Wireless A+B Broadband Router

8. I can’t get the Internet game,server,or application to work.

If you are having difficulties getting any Internet game, server, or application to function properly, consider exposing one PC to the Internet using DeMilitarized Zone (DMZ) hosting. This option is available when an application requires too many ports or when you are not sure which port services to use. Make sure you disable all the forwarding entries if you want to successfully use DMZ hosting, since forwarding has priority over DMZ hosting. (In other words, data that enters the Router will be checked first by the forwarding settings. If the port number that the data enters from does not have port forwarding, then the Router will send the data to whichever PC or network device you set for DMZ hosting.) Follow these steps to set DMZ hosting:

A. Access the Router’s web-based utility by going to http://192.168.1.1 or the

IP address of the Router. Go to the Advanced => Port Forwarding tab. B. Disable or remove the entries you have entered for forwarding. Keep this

information in case you want to use it at a later time. C. Click the DMZ Host tab. D. Enter the Ethernet adapter’s IP address of the computer you want exposed

to the Internet. This will bypass the NAT firewall for that computer. Please

refer to “Appendix D: Finding the MAC Address and IP Address for Your

Ethernet Adapter” for details on getting an IP address.

Once completed with the configuration, click the Apply button.

9. I forgot my password,or the password prompt always appears when I am saving settings to the Router.

Reset the Router to factory default by pressing the Reset button for 10 seconds and then releasing it. If you are still getting prompted for a password when saving settings, then perform the following steps:

A. Access the Router’s web-based utility by going to http://192.168.1.1 or the

IP address of the Router. Enter the default password admin, and click the

Password tab.

B. Enter a different password in the Router Password field, and enter the

same password in the second field to confir m the password. C. Click the Apply button.

Instant Wireless®Series

7. I need to set up online game hosting or use other Internet applications.

If you want to play online games or use Internet applications, most will work without doing any port forwarding or DMZ hosting. There may be cases when you want to host an online game or Internet application. This w ould require y ou to set up the Router to deliver incoming packets or data to a specific computer. This also applies to the Internet applications you are using. The best way to get the information on what port services to use is to go to the website of the online game or application you want to use. Follow these steps to set up online game hosting or use a certain Internet application:

A. Access the Router’s web interface by going to http://192.168.1.1 or the IP

address of the Router. Go to the Advanced => Port Forwarding tab. B. Enter any name you want to use for the Customized Application. C. Enter the External Port range of the service you are using. For example,

if you want to host Unreal Tournament (UT), you would enter the range

7777 to 27900. D. Check the protocol you will be using, TCP and/or UDP. E. Enter the IP address of the PC or network device that you want the port

server to go to. For example, if the web server’s Ethernet adapter IP address

is 192.168.1.100, you would enter 100 in the field provided. Check

“Appendix D: Finding the MAC Address and IP Address for Your Ethernet

Adapter” for details on getting an IP address. F. Check the Enableoption for the port services you want to use. Consider the

example below:

Customized External Port TCP UDP IP Address Enable Application UT 7777 to 27900 X X 192.168.1.100 X Halflife 27015 to 27015 X X 192.168.1.105 X PC Anywhere 5631 to 5631 X 192.168.1.102 X VPN IPSEC 500 to 500 X 192.168.1.100 X

When you have completed the configuration, click the Apply button.

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