Linksys BEFCMUH4 User manual

Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Linksys BEFCMUH4
Cable Gateway with 4-Port
Switch/USB and 802.11b
Wireless-Ready
Quick Guide
COPYRIGHT & TRADEMARKS
Copyright 2002 RCA, All Rights Reserved. Microsoft,
Windows, and the Windows logo are registered trademarks
of Microsoft Corporation. All other trademarks and brand
names are the property of their respective proprietors.
FCC STATEMENT
The Linksys BEFCMUH4 has been tested and complies with
the specifications for a Class B digital device, pursuant to
Part 15 of the FCC Rules. These limits are designed to
provide reasonable protection against harmful interface in a
residential installation. This equipment generates, uses, and
can radio frequency energy and, if not installed and used
according to 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 is found by turning the equipment
off and on, the user is encouraged to try to correct the
interference by one or more of the following measure:
• Reorient or relocate the receiving antenna
• Increase the separation between the equipment of devices
• Connect the equipment to an outlet other than the receiver
• Consult a dealer or an experienced radio/TV technician for
assistance
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Table of Contents
CHAPTER 1: INTRODUCTION.............................................................................. 2
OVERVIEW ................................................................................................................. 2
SOFTWARE FEATURES ................................................................................................ 2
MINIMUM REQUIREMENTS......................................................................................... 4
PACKAGE CONTENTS.................................................................................................. 4
CHAPTER 2: USING THE LINKSYS BEFCMUH4 ............................................. 6
THE LINKSYS BEFCMUH4’S REAR PANEL ............................................................... 6
THE LINKSYS BEFCMUH4’S FRONT PANEL ............................................................. 7
CHAPTER 3: CONNECT THE GATEWAY ........................................................... 9
OVERVIEW ................................................................................................................. 9
CONNECTING YOUR HARDWARE TOGETHER AND BOOTING UP................................. 9
CHAPTER 4: CONFIGURE YOUR PCS ...............................................................11
OVERVIEW ............................................................................................................... 11
CONFIGURING WINDOWS 95, 98, AND MILLENNIUM PCS........................................ 11
CONFIGURING WINDOWS 2000 PCS........................................................................ 13
CONFIGURING WINDOWS XP PCS........................................................................... 14
CHAPTER 5: CONFIGURE THE GATEWAY..................................................... 15
CONFIGURING THE LINKSYS BEFCMUH4 .............................................................. 15
APPENDIX A: TROUBLESHOOTING ................................................................ 18
COMMON PROBLEMS AND SOLUTIONS ..................................................................... 18
FREQUENTLY ASKED QUESTIONS............................................................................. 29
APPENDIX B: GLOSSARY .................................................................................... 32
APPENDIX C: INSTALLING THE TCP/IP PROTOCOL ................................. 40
APPENDIX D: FINDING THE MAC ADDRESS AND IP ADDRESS FOR
YOUR ETHERNET ADAPTER ............................................................................. 43
APPENDIX E: SPECFICATIONS.......................................................................... 46
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Chapter 1: Introduction
Overview
Thank you for purchasing the Linksys BEFCMUH4 Cable Gateway. The
Linksys BEFCMUH4 provides the ideal solution for connecting your wireless
network to a high-speed broadband Internet connection and a 10/100 Fast
Ethernet backbone. Configurable as a DHCP server for your existing network,
the Linksys BEFCMUH4 acts as the only externally recognized Internet
gateway on your local area network (LAN) and serve as an Internet NAT
firewall against unwanted outside intruders. The Linksys BEFCMUH4 can also
be configured to filter internal users’ access to the Internet.
A typical gateway relies on a hub or a switch to share its Internet connection,
but the Linksys BEFCMUH4 channels this connection through the blazing, full
duplex of its built-in 10/100 4-Port Switch. This cutting-edge combination of
wireless router and switch technology eliminates the need to buy an additional
hub or switch and extends the range of your wireless network. Now your entire
wireless network can enjoy blazing broadband Internet connections supported
by its robust switched backbone. With the dual-function speed and power of
the Linksys BEFCMUH4, your network will take off at speeds faster than you
ever imagined possible.
Software Features
DOCSIS Features
 Cable Modem (CM) is 1.0 and non 1.1 upgradeable
 Concatenation, Fragmentation, Payload Header suppression, IGMP
and BPI and BPI Plus are supported features for DOCSIS 1.1
 4/16/32/64/128/256/512/1024 QAM Downstream Receiver
 2/4/8/16/32/64/128/256 QAM Advanced TDMA Upstream Transmitter
 Both IP and LLC filters are supported
 Sixteen (16) destination address filters and 256 multicast/unicast DA
filters
 Sixteen (16) independent upstream queues for multiple QoS support
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
USB Features
 OS (Win2K, XP, WinME) supported for USB interface
Wireless Features
 Supports at least one beacon/DTIM interval of within the range
20-1000κμs
 Supports reception of fragmented packets
 Supports reception of RTS and generation of CTS
Firewall Features
 Stateful Packet Inspection against both Denial of Service and
Distributed Denial of Service attacks and will protect against the
following:
 Reassembly attacks
 SYN Attack (SYN Flood)
 ICMP Flood
 Ping of Death Attack
 Tear Drop Attack
 IP Spoofing Attack
 LAND Attack
 Jolt
 Winnuke Attack (Netbios out-of-bound)
 OverDrop
 BONK, BOINK
 Blind Spoofing
 Echo/Chargen
 Storm
 Smurf Attack
 Mime Flood
 De-Militarized Zone (DMZ) which allows a computer on the LAN to
expose all of its ports to the WAN that are not otherwise filtered
 Logged Events which all security incidents will be logged
 Keyword blocking is based on keywords in a URL and can be
specified by the user
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NAT Requirements
The implementation of NAT must allow for specific port redirection. Listed
below are applications supported.
 FTP
 IRC
 H.323
 Quake
 Blizzard games
 Chat ALG
 Real Audio/Video
 CUSEEME
 Netmeeting
 MS Games but not with game zone
 DIABOLO II
 Activision Games
 PCAnywhere
 SSL
 NNTP
 Port Forwarding, incoming traffic that is not part of an existing
connection will be dropped unless the user specifies forwarding of the
server to a host on the LAN
Virtual Private Network (VPN) Feature
 Having the ability to enable or disable PPTP and IPSec pass through
Minimum Requirements
One RJ-45 Broadband Internet connection, with a Cable Modem





One PC with an installed 10Mbps, 100Mbps, or 10/100 Mbps Ethernet
card (optional)
TCP/IP network protocol for each PC
UTP network cable with RJ-45 connector
Microsoft Internet Explorer 4.0 or later, or Netscape Navigator 4.0 or later.
(5.0 and 4.7, respectively, are strongly recommended.)
Windows 95, 98, Millennium, NT 4.0, 2000 or XP
Package Contents
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
 {1} Cable Modem
 {1} AC Power adapter
 {1} CAT.5 Ethernet cable {RJ-45}
 {1} USB cable
 {1} User’s Manual
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
the Gateway’s data and restore the factory defaults. This should be done only
if you are experiencing heavy routing problems, and only after you have
exhausted all of the other troubleshooting options. By resetting the Gateway,
you run the risk of creating conflicts between your PCs’ actual IP Addresses
and what the Gateway thinks their IP Addresses should be. You may be forced
to reboot the entire system(s).
If your Gateway locks up, simply power it down for 5 seconds by removing the
power cable from the Gateway’s Power Port. Leaving the power off for too
long could result in the loss of network connections.
The Linksys BEFCMUH4’s Front Panel
Power Green. The power LED illuminates when the device is powered
on.
Diag Red. The Diag LED illuminates when the device goes through its
self-diagnosis mode during boot-up and restart. It will turn off
upon successful completion of the diagnosis.
The LAN indicators
USB Green. The USB LED illuminates when the USB port is properly
connected to your PC.
WLAN Green. The WLAN LED illuminates when the Wireless PC card
slide-in.
Link/Act Green. Steady on when link is up and blinking when data is
following through this LAN port.
Full/Col Green. Steady on when it operates at full duplex mode. Off at
half duplex mode. Blinking when collision is occurred on this
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
port.
10/100 Green. Steady on when a successful 100Mbps connection is
made through the corresponding port.
The WAN indicators
Cable Green. Steady on when cable is registered and ready to transfer
data. Blinking when no downstream RF carrier present.
Receive Green. Blinking when user data going through the cable modem
to PC present.
Send Green. Blinking when user data going through the cable modem
from PC present.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Chapter 3: Connect the Gateway
Overview
Unlike a simple hub or switch, the Gateway’s setup consists of more than
simply plugging hardware together. You will have to configure your networked
PCs to accept the IP addresses that the Gateway assigns them (if applicable),
and you will also have to configure the Gateway with setting(s) provided by
your Internet Service Provider (ISP).
The installation technician from your ISP should have left the setup
information with you after installing your broadband connection. If not, you can
call your ISP to request the data.
Once you have the setup information you need for your specific type of
Internet connection, you can begin installation and setup of the Gateway.
Connecting Your Hardware Together and Booting Up
1. Before you begin, make sure that all of you hardware is powered off,
including the Gateway, PCs, hubs, and switches.
2. Connect one end of an Ethernet cable to one of the LAN ports (labeled 1, 2,
3, or 4) on the back of the Gateway and the other end to a standard port on
a network device, e.g., a PC, print server, hub, or switch. Repeat the above
step to connect more PCs or network devices to the Gateway.
3. Connect the cable from your ISP to the Cable port on the Gateway’s back
panel.
4. Connect the power-supply cable to the Power port on the rear of the
Gateway, then plug the supplied AC power cable into a power outlet and
power on the Linksys BEFCMUH4.
• The Power LED on the front panel will light up green as soon as the
power adapter is connected properly.
• The Diag LED will light up red for a few seconds when the Gateway
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
goes through its self-diagnostic test. The LED will turn off when the
self-test is complete.
5. Power on the network devices that connected to the Linksys BEFCMUH4.
The Hardware Installation is complete. Continue to the next page to
configure your PCs with Linksys BEFCMUH4.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Chapter 4: Configure Your PCs
Overview
The instructions in this chapter will help you configure each of your computer
to be able to communicate with the Gateway.
To do this, you need to configure your PC’s network settings to obtain an IP (or
TCP/IP) address automatically (called DHCP). Computers use IP addresses to
communicate with each other across a network or the Internet.
Find out which operating system your computer is running, such as Windows
95, 98, Millennium, NT 4.0, 2000, or XP. You will need to know which operating
system your computer is running. You can find out by clicking the Start button
and then going to the Settings option. Then click Control Panel, and then
double-click the System icon. If your Start menu doesn’t have a Settings
option, you’re running Windows XP. Click the Cancel button when done.
You may need to do this for each computer you are connecting to the
Gateway.
Important: These instructions apply only to Windows 95, 98, Millennium, 2000,
or XP machines. For TCP/IP setup under Windows NT, see your Windows
manual. By default Windows 98, 2000, Me, and XP has TCP/IP installed and
set to obtain an IP address automatically.
The next few pages tell you, step by step, how to configure your network
settings based on the type of Windows operating system you are using. Make
sure that an Ethernet card or adapter has been successfully installed in each
PC you will configure. Once you’ve configured your computers, continue to
“Chapter 5: Configure the Gateway”
Configuring Windows 95, 98, and Millennium PCs
1. Go to the Network screen by click the Start button. Click Settings and then
Control Panel. From there, double-click the Network icon.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
2. On the Configuration tab, select the TCP/IP line for the applicable Ethernet
adapter. Do not choose a TCP/IP entry whose name mentions DUN,
PPPoE, VPN, or AOL. If the work TCP/IP appears by itself, select that line.
(If there is no TCP/IP line listed, refer to “Appendix C: Installing the TCP/IP
Protocol.) Click the Properties button.
3. Click the IP Address tab. Select Obtain an IP address automatically.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
4. Now click the Gateway tab to ensure that the Installed Gateway field is left
blank. Click the OK button.
5. Click the OK button again. Windows may ask you for the original Windows
installation disk or additional files. Supply them by pointing to the correct
file location, e.g., D:\win98, D:\win9x, c:\windows\options\cabs, etc. (if “D”
is the letter of your CD-ROM drive).
6. Windows may ask you to restart your PC. Click the Yes button. If Windows
does not ask you to restart, restart your computer anyway.
Go to “Chapter 5: Configure the Gateway.”
Configuring Windows 2000 PCs
1. Go to the Network screen by clicking the Start button. Click Settings and
then Control Panel. From there, double-click the Network and Dial-up
Connections icon.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
2. Select the Local Area Connection icon for the applicable Ethernet
adapter (usually it is the first Local Area Connection listed). Double-click
the Local Area Connection. Click the Properties button.
3. Select Internet Protocol (TCP/IP), and click the Properties button.
4. Select Obtain an IP address automatically. Once the new window
appears, click the OK button. Click the OK button again to complete the
PC configuration.
5. Restart your computer.
Go to “Chapter 5: Configure the Gateway.”
Configuring Windows XP PCs
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.
1. Go to the Network screen by clicking the Start button and then Control
Panel. From there, double-click the Network Internet Connections icon
and then the Network Connections icon.
2. Select the Local Area Connection icon for the applicable Ethernet
adapter (usually it is the first Local Area Connection listed). Double-click
the Local Area Connection. Click the Properties button.
3. Select Internet Protocol (TCP/IP), and click the Properties button.
4. Select Obtain an IP address automatically. Once the new window
appears, click the OK button. Click the OK button again (or the Close
button if any settings were changed) to complete the PC configuration.
5. Restart your computer.
Go to “Chapter 5: Configure the Gateway.”
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Chapter 5: Configure the Gateway
Configuring the Linksys BEFCMUH4
This chapter will show you how to configure the Gateway to function in your
network and gain access to the Internet through your Internet Service Provider
(ISP). Your ISP may require the use of a Host Name and Domain Name. You
will need the setup information from your ISP. If you do not have this
information, please contact your ISP before proceeding.
The instructions from your ISP will tell you how to set up your PC for Internet
access. Because you are now using the Gateway to share Internet access
among several computers, you will use the setup information to configure the
Gateway instead of your PC. You only need to configure the Gateway once
using the first computer you set up.
1. Open your web browser. (It is all right if you get an error message at this
point. Continue following these directions,) Enter http://192.168.100.1 in
the browser’s Address field. Press the Enter key.
2. An Enter Network Password window, shown in below figure, will appear
(For Windows XP users, the screen may look different). Leave the User
Name field empty, and enter admin in lowercase letters in the Password
field (admin is the default password). Then, click the OK button.
3. The Gateway configuration screen will appear. Press Basic tab and then
select Setup menu. Based on the setup instructions from your ISP, you
may need to provide the following information.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
LAN IP Address: The value for the Gateway’s IP address is shown on the
Setup screen. The default value is 192.168.100.1. Leave these settings
alone.
Host Name and Domain Name: These fields allow you to provide a host
name and domain name for the Gateway. These fields are usually left
blank. If requested by your ISP, complete these two fields.
Static IP Address and IP Mask: If your ISP says that you are connecting
through a static or fixed IP address from your ISP, you should enter the
field of Default Gateway, Primary DNS and/or Secondary DNS also.
Spoofed MAC Address: An essential component of penetration testing
and network wargames is the ability to specify arbitrary MAC addresses.
The Gateway can significantly reduce the ability of intruders to use spoofed
MAC address to compromise or disrupt systems. Spoofed MAC addresses
can also be used locally to redirect traffic from its intended host to the
hacker's machine.
4. The Gateway also provided Security and DHCP settings in Basic tab. You
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
can change the access priviledge and restore factory default of the
Gateway. Also, you can enable/disable the DHCP Server function.
IMPORTANT: If you have previously enabled any Internet-Sharing Proxy
server software on any of your PCs, you must disable it now.
Some examples of Internet-sharing software are Internet LanBridge,
Wingate, ICS, and Sygate. To disable your Internet-sharing software:
• If you are running Netscape Navigator: Click Edit >> Preference >>
Advanced >> Proxies > and click Direct Connection to the Internet.
• If you are running Internet Explorer v5 or better, click Start >> Settings
>> Control Panel >> Internet Options >> Connections >> LAN
Settings. Remove the checks from all three boxes. Click OK to
continue.
Also, you must disable any Internet log-on software (such as Ivasion
Winpoet or Enternet 300) and any firewall software (such as ZoneAlarm
and Watchdog) on all of your PCs.
5. If you have already done so, click the Apply button to save your settings.
Close the web browser.
6. Restart your computers so that they can obtain the Gateway’s new
settings.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Appendix A: Troubleshooting
Common Problems and Solutions
This section provides possible solutions to problems regarding the installation
and operation of the Linksys BEFCMUH4. If your situation is described here,
the problem should be solved by applying the corresponding solution. If you
can’t find an answer here, please contact with your local dealer.
1. I need to set a static IP address on a PC.
The Gateway, by default, assigns an IP address range of 192.168.100.10 to
192.168.100.41 using the DHCP server on the Gateway. To set a static IP
address, you can only use the ranges 192.168.100.2 to 192.168.100.9 and
192.168.100.42 to 192.168.100.254. 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 IP conflict error
message. You can assign a static IP address to a PC by performing the
following steps:
For Windows 95, 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, you will only see one TCP/IP line with no
association to an Ethernet adapter. Highlight it and click the Properties
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 Gateway. You can only
use an IP address in the ranges 192.168.100.2 to 192.168.100.9 and
192.168.100.42 to 192.168.100.254. Make sure that each IP address is
unique for each PC or network device.
D. Click the Gateway tab, and in the New Gateway prompt, enter
192.168.100.1, which is the default IP address of the Gateway. Click the
Add button to accept the entry.
E. Click the DNS tab, and make sure the DNS Enabled option is selected.
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Linksys BEFCMUH4 Cable Gatewayr + 802.11b Wireless-Ready
Enter the Host and Domain names (e.g., Johnson 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.
For Windows 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 Gateway. You can only use an IP address in the
ranges 192.168.100.2 to 192.168.100.9 and 192.168.100.42 to
192.168.100.254.
E. Enter the Subnet Mask, 255.255.255.0.
F. Enter the Default Gateway, 192.168.100.1 (Gateway’s default IP address).
G. Toward the bottom of the window, select Use the following DNS server
address, and enter the Preferred DNS server and Alternative DNS
server (provided by your ISP). Contact your ISP or go on its website 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. Restart the computer if asked.
For Windows NT 4.0:
A. Click Start, Settings, and Control Panel. Double-click 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.
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