Cisco Comcast Xfinity DPC3939 User manual

 Wireless Gateway 2
Model Numbers: DPC3939, TC8706C
Quick Start Guide
Wireless Gateway 2
Wi‑Fi
Devices

2
About the Wireless Gateway 2 (Model Numbers: DPC3939, TC8706C)
The Wireless Gateway 2 is an all-in-one product that connects XFINITY Internet,
XFINITY Voice, and home networking. It provides wired and Wi-Fi connectivity, so
there’s no need for a separate router.
•Dual-Band Wi-Fi 2.4 & 5 GHz
•Parental Controls
•Firewall
•Port Forwarding & Blocking
•Wi-Fi Protected Setup (WPS)
Learn how Wi‑Fi and
5 GHz
works in your home.
Check out p. 6.
This Quick Start Guide will help you:
Step Find Your Default Wireless Network Info
Step Connect Your Wi-Fi Devices
Step Log In and Secure the Admin Tool
Step . Find Your Default Wireless Network Info
A LifttheWirelessGateway
toviewthebottompanel
On the bottom panel label, find
the two Network Names (SSIDs)
and the one Network Key
(Password). The case-sensitive
password is the same for both
Network Names (SSIDs).
B Writedownyour
information
In the lines below, write
down your wireless network
information for future reference.
Wireless “Network Name (SSID 1)” for 2.4 GHz Wi-Fi Band (Example: HOME-XXXX-2.4)
Wireless “Network Name (SSID 2)” for 5 GHz Wi-Fi Band (Example: HOME-XXXX-5)
Wireless “Network Key (Password)” Same for both bands (case-sensitive)
Wireless
Network Names
(SSIDs)
Wireless
Network Key
(Password)
Gateway’s
Bottom Panel
Note: The default Network Names (SSIDs) and Network Key (Password) are unique to your Wireless Gateway. If
you’d like to change them, see p. 5. We recommend changing the Network Key (Password).

3
Step 2. Connect Your Wi-Fi Devices
Now that you have your wireless network information, you’re ready to connect your
Wi-Fi devices (laptops, tablets, mobile devices) to the Wireless Gateway 2.
Follow the steps below for each Wi-Fi device you want to connect to your home
network.
For the best experience from the Wireless Gateway 2, connect to both 2.4 and
5 GHz networks, if your Wi-Fi device supports both networks (p. 6). If it does not,
only connect to the 2.4 GHz network.
A GototheWi-Fi SettingsonyourWi-Fidevice andensure
Wi-Fiisturnedon
Directions to access the Wi-Fi settings for popular operating systems are below. If
your operating system is not listed, refer to the manufacturer’s guides.
Windows
On your Windows®Desktop,
click the Wireless Network icon.
Android
From the Apps screen, tap the
Settings icon. Tap Wireless &
Networks, then Wi-Fi Settings.
Apple Mac OS X
On your Mac®Desktop, click
the Wi-Fiicon.
Apple iOS
(iPad, iPhone, iPod Touch…)
From the Home Screen, tap the
Settings icon. Tap the Wi-Fi icon.
B SelecttheGHzNetworkName
(SSID)onyourWi-Fidevice 
Under the Wi-Fi settings, the list of available
networks should appear. Select your home
network (such as Home-XXXX-2.4) from
Step1.
C EntertheNetworkKey(Password)on
yourWi-Fidevice 
When prompted, enter the case-sensitive
Network Key (Password) from Step 1. Tap the
confirmation button—usually labeled Join,
Connect, or OK.

4
D CheckifyourWi-Fidevice is
connectedtoyourGHznetwork
If your Wi-Fi device is connected, you should
see a check mark (or other indication) next to
the Network Name (SSID) you had selected.
E TestyourInternetconnectiononyourWi-Fidevice 
Open a web browser (Internet Explorer or Safari), and try to access a site, such as
www.xfinity.com.
F ConnectyourWi-Fidevice to
theGHzband
If your device supports 5 GHz, you should
see Home-XXXX-5. To connect to 5 GHz,
repeat Steps 2A-2E. If you don’t see your
5 GHz network or you don’t have a 5 GHz
Wi-Fi capable device, skip this step.
Note: For help with the above steps or to learn about Wi-Fi and 5 GHz, see p. 5-7.
Step 3. Log In and Secure the Admin Tool
You can manage your network and security settings using the Wireless Gateway 2’s
Admin Tool. To ensure better security for your Wireless Gateway 2 and home network,
we recommend changing the default password to a password of your own.
A Open a web browser from a connected wired or Wi-Fi device . Go to
http://10.0.0.1 and the Login page appears.
B Enter admin for Username.1Enter password
for Password.
C Click LOGIN and the At a Glance page
appears.
D Click CHANGE PASSWORD for Increased
Security (recommended).
1. Enter “password” in the Current Password
field.
2. Create a new password of your choice.2
3. Re-enter your new password.
4. Click “Save”.
5. Your settings should now be saved.
1The username “admin”cannot be changed.
2The password must be at least 8 characters
and may include letters or numbers or a
combination of both (no symbols). For better
security, try using at least 1 number and a mix
of upper and lower case letters.

5
The Wireless Gateway 2 enables you to personalize your home network. Features that
can be customized using the Admin Tool include:
• ParentalControls: Create rules for different network devices.
• Firewall: Manage network security settings.
• WirelessNetworkInfo:
The default NetworkNames(SSIDs)
can be changed. You may find it helpful
to keep the -2.4 and -5 in the Network
Names (SSIDs) to distinguish between
the two network bands.
The default NetworkKey(Password),
which is the same for both 2.4 and
5 GHz network bands, can be changed. You can change each band separately
or use the same password for both. Keep in mind that they are case-sensitive.
Note: To edit your wireless network info in the Admin Tool, go to Gateway > Connection > Wi-Fi.
For more information about the Wireless Gateway 2, visit
http://customer.comcast.com/userguides and download the User Guide.
Wi-Fi Connectivity Tips
If you’re having trouble connecting a Wi-Fi device to your 2.4 and 5 GHz Wi-Fi
networks (or if neither network appears in the available networks list), simple actions
may help.
Try the following tips in order. After trying a tip, see if you can connect to your network
by repeating Steps 2A-2F (p. 3-4). If you can’t connect, try the next tip.
Tip Move the Wi-Fi device next to the Wireless Gateway 2.
Tip On the Wi-Fi device, turn the Wi-Fi setting off and then on.
Tip Restart the Wi-Fi device by powering off and then on.
If none of the above tips resolve your connection issue, reset the Wireless Gateway 2.
Caution: Resetting the Gateway will disrupt XFINITY Voice and Internet services for
at least five minutes. Therefore, during the reset, you’ll be unable to make or
receive any calls, including calls to 911 or emergency services.
Following are two ways to reset the Wireless Gateway 2.
• Use a thin object to press the Reset button on the back panel.
Hold for 2-5 seconds, and then release.
Caution: Holding the Reset button for 15 seconds or more will
restore default factory settings. Any changes you’ve
made to the Wireless Gateway 2 (such as passwords,
parental controls, or firewall settings) will be lost.
Or
• UnplugtheWirelessGateway2andremovethebatteryfromthe
bottom panel (if you have one). Replace the battery, then replug.
If you change your default
wireless network settings, write
down the information to replace
the default wireless network
settings on p. 2. You’ll need the
new information to connect
Wi‑Fi devices to your network
in the future.

6
Wireless Gateway 2 Placement
Where you put the Wireless Gateway 2 in your home can affect your connectivity,
range (operating distance), and performance of connected Wi-Fi devices . For
optimal results from the Wireless Gateway 2, follow these guidelines to identify your
home’s ideal location.
• Place the Wireless Gateway 2 in an upright, elevated location (closest to the center
of where you’ll typically use your Wi-Fi devices).
• Minimize the number of walls and ceilings between the Wireless Gateway 2 and
your Wi-Fi devices.
• Place the Wireless Gateway 2 away from electronics that may cause interference
(such as microwaves and cordless phone bases).
5 GHz in Your Home
Most Wi-Fi networks primarily operate in the 2.4 GHz frequency band only, but the
increasingly popular 5 GHz networks offer significant advantages. With dual-band
Wi-Fi devices , you’ll experience the benefits of both 2.4 and 5 GHz networks.
Why use 5 GHz?
• Higher speed capability than 2.4 GHz
• Less wireless interference in the 5 GHz band
• Large data, such as video or game files, download faster than with 2.4 GHz
because 5 GHz can support higher speeds
• Compatible with many newer 5 GHz Wi-Fi consumer electronic devices, such as:
Tablets Mobile Phones
Laptops Game Systems
HD TVs
About Wi-Fi and the Wireless Gateway 2
• Not all Wi-Fi devices support 5 GHz,
especially older ones. If your device is
5 GHz capable, you should see the 5 GHz
Network Name (SSID) in the list of available
networks (p. 3-4). If you don’t, and you’re
unsure if your Wi-Fi device supports 5 GHz,
check the manufacturer’s documentation.
• Although the Wireless Gateway 2 simultaneously broadcasts both 2.4 and 5 GHz,
Wi-Fi devices can connect to only one Wi-Fi network at a time.

7
• 5 GHz Wi-Fi signals may not travel as far as 2.4 GHz. In areas of your home that
are furthest away from the Wireless Gateway 2, only the 2.4 GHz network may
be available. We recommend connecting to both 2.4 and 5 GHz networks during
initial set-up of all your Wi-Fi devices .
If you’re connected to the Wireless Gateway 2’s 5 GHz network and move out
of the 5 GHz range (move to a different room), your Wi-Fi device may
disconnect and automatically reconnect to your 2.4 GHz (if you’ve connected to it
previously).
Note: When you’re back in the 5 GHz range, go to Wi-Fi settings (p. 3-4) to reconnect to the Wireless
Gateway 2’s 5 GHz network in order to experience its benefits.
• The Wi-Fi bars on your Wi-Fi device indicate signal strength.
• Some Wi-Fi devices support Wi-Fi Protected Setup (WPS).
WPS lets you set up secure Wi-Fi networks without manually
entering your Wi-Fi network information. Pressing the WPS button
on the Wireless Gateway 2 initiates WPS for both 2.4 and 5 GHz Wi-Fi bands. You
can then connect to either band using WPS.
Learn about the Wireless Gateway 2 at http://customer.comcast.com/userguides.
For questions about your XFINITY services, call 1-800-XFINITY.
Windows is a registered trademark of Microsoft Corporation in the United States and other countries. Mac OS®and
OS X®are registered trademarks of Apple Inc. IOS is a trademark or registered trademark of Cisco in the U.S. and
other countries and is used under license. Android is a trademark of Google Inc. All trademarks are the property of
their respective owners. © 2013 Comcast. All rights reserved.

ENG WG2XB3 QSG 07.13