Netgear Cmd31t Docsis 3 0 Cable Modem Installation Guide

							Installation Guide
Note:The MAC address and serial 
number can also be found in the product 
label on the bottom of the unit.
Part 1: Unpack the Shipping Carton
Verify that all items are present.
MAC address:
Serial number:
Ethernet cable
Power adapter
CMD31T Cable Modem
Part 2: Install the Cable Modem
1.   Complete the connections as shown in the connections diagram.
a.  Connect the coaxial cable to the NETGEAR CMD31T Cable Modem.
b.  Use the Ethernet cable to connect your laptop or computer to the 
NETGEAR CMD31T Cable Modem.
c.  Connect the power adapter.
2.   Power on your computer.
Note:It takes at least 15 minutes for your NETGEAR CMD31T Cable Modem to 
come online on the network.
c.
a.
b.
3.   Wait until the cable modem status shows online. After the modem registers 
with your cable Internet service provider, the following LEDs should be lit:
•    
 Power LED: Solid green
•    
 Online LED: Solid green
If the Power LED is not solid green, check your power adaptor connections.
Part 3: Contact Your Cable Operator
1.   Call your cable operator and tell the customer service person that you are 
installing a new cable modem
 that you have bought from a retail store.
Note:The contact information listed may change. The contact number can also 
be found in your monthly broadband billing statement.
2.   When asked, provide the cable modem’s serial number and MAC address 
listed on the front page of this installation guide.
3.   Wait for the customer service operator to confirm that your device is active.
•    If you do not have Internet connection with the new NETGEAR cable 
modem, then you should ask the customer service agent to verify whether 
he or she can see your cable modem
 online.
•    If not, the customer service agent should help you with instructions to verify 
why the cable modem
 does not connect with your high-speed Internet 
service.
•    If the customer service agent can confirm that your cable modem is visible as 
online to the agent, then you should reboot your computer or laptop or home 
gateway that is connected to your cable modem
. Try checking your online 
status again. 
You are now able to enjoy your Internet service with the NETGEAR CMD31T 
Cable Modem.
Cable Service Provider Contact Information
Cablevision: www.cablevision.comComcast: 1-800-COMCAST (1-800-266-2278)
Charter: 1-888-438-2427 Time Warner Cable: 1-800-892-2253
CMD31T Cable Modem
Visit http://www.netgear.com/CMD31T for information about connecting your device 
with your cable operator. 
						

							January 2013
LEDs
Power 
•Solid green: Power is on.
•Off: Power is off.
Online 
(Cable Link) 
•Green blinking: The cable modem is online and processing 
traffic.
•Off: The cable modem is off line.
US (Upstream)•1/2 solid amber: Upstream Channel 1 is in use.
•1/2 solid green: Upstream Channels 1 and 2 are in use.
•3/4 solid amber: Upstream Channels 1, 2, and 3 are in use.
•3/4 solid green: Upstream Channels 1, 2, 3, and 4 are in use.
•Off: No upstream channel is in use.
DS (Downstream)•1/2 solid amber: Downstream Channel 1 is in use.
•1/2 solid green: Downstream Channels 1 and 2 are in use.
•3/4 solid amber: Downstream Channels 1, 2, and 3 are in use.
•3/4 solid green: Downstream Channels 1, 2, 3, and 4 are in use.
•Off: No downstream channel is in use.
Ethernet •Solid green: A 1 Gbps device is connected and detected on the 
Ethernet port.
•Solid Amber: A 100 Mbps device is connected and detected on 
the Ethernet port.
•Solid Red: A 10 Mbps device is connected and detected on the 
Ethernet port.
•Blinking: There is data traffic on the Ethernet port.
•Off: No device is detected on the Ethernet port.
Troubleshooting
No LEDs are lit 
on the cable 
modemThe cable modem has no power. Make sure that:
• The power adapter is correctly connected to the cable modem.
• The power adapter is correctly connected to a functioning power 
outlet. If it is to a power strip, make sure that the power strip is 
turned on.
• You are using the correct power adapter.
Online LED 
does not light 
upThere is a hardware connection problem, or you do not have cable 
service. Do the following:
• Make sure that the cable connector is securely plugged in at the 
cable modem.
• Turn the power to the cable modem off and on.
• You might not have active cable service yet. Contact your provider to 
verify activation.
Ethernet LED 
does not light 
up even though 
a device is 
attachedThere is a hardware connection problem. Do the following:
• Make sure that the cable connector is securely plugged in to the 
cable modem and the computer.
• If you are not using the cable included with the cable modem, check 
that the Ethernet cable is a straight-through patch cable.
You cannot 
connect to the 
InternetIt can take up to 15 minutes to establish a connection the first time you 
power on your cable modem. Always leave your cable modem plugged 
in to AC power and connected to the cable system. Do the following:
• Check your cable connections. Connectors should be finger tight.
• Make sure that you have powered up in the following sequence:
-  Turn on your cable modem first, and wait until the LEDs stop 
flashing.
-  If your computer is connected to the cable modem, turn on the 
computer.
• If you have a home network, check the TCP/IP configuration.
-  For Windows, the network properties should be set to obtain an IP 
address automatically.
-  For Macintosh computers, the TCP/IP (or Network) control panel 
should be set to Using DHCP Server.
Support
Thank you for purchasing this NETGEAR products.
After installing your device, locate the serial number on the label of your product and 
use it to register your product at 
https://my.netgear.com. 
You must register your product before you can use NETGEAR telephone support. 
NETGEAR recommends registering your product through the NETGEAR website.
For product updates and web support, visit
http://support.netgear.com.
NETGEAR recommends that you use only the official NETGEAR support 
resources.
You can get the user manual online at
 http://downloadcenter.netgear.com or through a link in the product’s user interface.
Trademarks
NETGEAR, the NETGEAR logo, and Connect with Innovation are trademarks and/or registered 
trademarks of NETGEAR, Inc. and/or its subsidiaries in the United States and/or other countries. 
Information is subject to change without notice. © NETGEAR, Inc. All rights reserved.
Compliance
For the current EU Declarations of Conformity, visit: 
http://support.netgear.com/app/answers/detail/a_id/11621/. 
Intended for indoor use only in all EU member states, EFTA states, and Switzerland.