Motorola MB8611 User manual

DOCSIS 3.1 cable modem
with 2.5 Gbps LAN port
Model MB8611
Quick Start
Guide

2
Packaged with your MB8611 modem
Power Adapter
Coax Wrench
Ethernet Cable
Velcro®Cable
Organizer
Para una Guía de Inicio Rápido en español, por favor vaya a
www.motorolanetwork.com/MB8611ir

3
Let’s get started
1Call your cable service provider to order cable Internet
service if you don’t already have it. Mention that your
MB8611 supports DOCSIS 3.1, the fastest cable modem
service standard. Your MB8611 also supports all speeds of
any DOCSIS 3.0 services.
Or, if you already have cable service, you should have
your account number handy in case you need it during
the activation process. You can generally find the
account number on the landing page when you log in to
your cable service provider account. You can also find it
on a recent cable bill.
2 Now connect your MB8611 as shown on the next panel.
Connecting to a coax cable
See the connection photo on the next panel. Connect
your MB8611 to a “live” coax cable. Sometimes a cable will
already be available. Sometimes there’s a coax wall jack
available, and you connect to the jack with a coax cable.
Your MB8611 can also share a coax cable attached to a TV
by using a coax splitter. Please note that a badly chosen
splitter may reduce a cable modem's speed or prevent
connection to the network. If you need to use a splitter,
use a two-way splitter whose top frequency is 1,000 MHz
or higher.

4
RESET button
ETHERNET (LAN)
You can connect a WiFi router,
computer, HDTV, game station,
or other Ethernet-capable
device. To connect your router,
see
If you want to connect a
router
, below.
COAX
Connect a “live” coax
cable to the modem’s COAX
connector as discussed
above. (Use the wrench to
tighten the nut finger-tight: Do
not overtighten.)
ON/OFF button
POWER
Connect the supplied power
adapter between the power
jack and an electrical outlet.

5
Prepare to activate
Power up your cable modem. To do this, the On/Off button
needs to be On (Push the button in until it clicks). Wait for
the online connection light ( for 3.0, or for 3.1) to stop
flashing and remain solidly lit. This may take up to 15
minutes.
Activate with your service provider
Some service providers allow you to activate by calling them.
Others, like Comcast Xfinity and Cox, prefer that you activate
by opening the Web browser of a computer that’s plugged
into the MB8611’s Ethernet port.
If you have a computer, plug it into the MB8611’s Ethernet
port. Once you've opened the computer’s browser, go to
your service provider’s web page. This should bring you
directly to the service provider's activation page. Follow the
onscreen instructions.
If you don’t have a computer, you can normally activate by
calling your service provider.
Another option is to first connect a WiFi router to the MB8611
as described on page 7 of this Quick Start. Then use the
browser of your smartphone, tablet, or other WiFi device to
go to your service provider’s web page, where you should
see an activation page’s onscreen instructions.

6
For Comcast XFINITY Users Only:
If the activation page does not appear, please go to
www.xfinity.com/activate for more information and to
activate your modem.
Here is a list of phone numbers for some major cable service
providers. (Note that this list is subject to change.)
Comcast Xfinity
1 [phone]
Cox
1 [phone]
Bright House (Spectrum)
1 [phone]
Sparklight (Cable One)
1 [phone]
Charter Spectrum
1 [phone]
MediaCom
RCN
1 (844) 987
-3260
1 [phone]
Altice Suddenlink
1 [phone]
Time Warner (Spectrum)
WOW!
1 (855) 707
-7328
1 [phone]
Once your MB8611 is activated either online or by phone, your
service provider will provision your MB8611 service. Typically
this takes less than 5 minutes, but in some cases this may
take 30 minutes or longer to complete.
Once you have activated, you should have Internet access for
whatever’s plugged into your cable modem.
Congratulations!
If your cable modem is NOT working, see Troubleshooting
Tips below.
Note: You can connect this device to a WiFi router,
computer, Internet capable TV, game station, or other
Ethernet-capable device.
This product does not include
a router, WiFi, or telephone capability.

7
If you want to connect a router
Most users will connect a WiFi router to the MB8611. This
connection may be made initially, before activating the
cable modem, or it may be done after the cable modem
has been activated. A wireless router lets multiple devices
(computers, smartphones, tablets, video devices, game
stations…) share your cable modem’s Internet connection,
either wirelessly or through a direct Ethernet connection.
The MB8611 has a 2.5 Gbps Ethernet LAN port for
connecting a router. This is unusually fast and flexible, and
it supports router WAN port speeds from 100 Mbps to 2.5
Gbps.
1. The cable modem and the router should both be
powered off.
2. Plug one end of the cable modem’s Ethernet cable into
the Ethernet jack of your modem and plug the other
end of the cable into the router’s WAN port. (You may
need to disconnect the cable from your computer
first.)
3. Power-up the cable modem. Wait for the ONLINE light
( or ) to be solidly lit.
4. Power-up the router. Wait for the router to complete
its power-up sequence.
5. The Ethernet port light on your modem should be
lit to show the Ethernet connection to your router.
Note the color will be white for 100BT, green for 1 Gig
Ethernet, and blue for 2.5Gig Ethernet.
6. Follow your router’s instructions for setting up the
router and connected devices.
If you haven’t already activated your Internet service, do
that now. (See Prepare to activate on page 5.) Using a
computer or other device connected to the router, try
connecting to the Internet. If it works, Congratulations!
Installation is complete.

8
MB8611 Lights
LIGHT
COLOR
DESCRIPTION
Power
Green
ON:
Cable modem power on
OFF:
Cable modem power off
Downstream
Green or
Blue
Green
Blinking:
Scanning for DS channel
Green
ON:
Connected on
1 downstream channel
Blue
Blinking:
Negotiating
bonded channel(s)
†
Blue ON:
Bonded with 2 or more
channels
Upstream
Green or
Blue
Green
Blinking:
Ranging in progress
Green
ON:
Connected
on 1 channel
Blue
Blinking:
Negotiating bonded
channel(s)
†
Blue ON:
Bonded with 2 or more channels
OFF:
Upstream not connected
Online
Green
or
Blue
Blinking:
Trying to go online
Green:
Online with DOCSIS 3.0
Blue:
OFF:
Online with DOCSIS 3.1
Offline
LAN
White,
Green
or
Blue
Blinking:
Ethernet data is flowing
White:
Ethernet link at 100BT
Green:
Ethernet link at 1GE
Blue:
Ethernet link at 2.5GE
Rear Panel
Ethernet
LAN port(s)
Green or
Amber
Blinking:
Ethernet data is flowing
Green:
Connected at 2.5GE
Amber:
Connected at 100Mbps
,
or 1GE
OFF:
No connection
†If a blue Upstream or Downstream light blinks continuously, this indicates
partial service (at least one designated channel has not completed
bonding). You should still get high Internet speeds, but your service
provider may want to know so they can adjust their network.

9
Troubleshooting Tips
What if I can’t make an Internet connection right after
installation?
•First turn your cable modem off for at least 8 seconds, then
on, to see if that fixes the problem.
•Check the connections you’ve made to your cable modem –
power, Ethernet, and coax. Are those connections good?
•Check that the modem’s power cube is plugged into a live
outlet, and that the Ethernet cable is connected securely.
•Make sure that your coax cable is live. You can check that by
using it with a TV.
•Check that you provided the correct setup information to
your cable service provider.
•Contact your cable service provider to make sure they’ve
turned on your Internet service.
What if my cable modem has been working, and then stops
working?
•First turn your cable modem off for at least 8 seconds, then
on, to see if that fixes the problem.
•If the modem’s lights don’t come on, check that the modem
is getting power from its power cube and that the modem’s
power button is on.
•Check your cable modem cables.
•Check with your service provider. Sometimes there’s a
service outage or some other service issue.
What if I’m getting Internet service but my speed is
disappointing?
•Be sure you know what speed you’re paying for.
•Check the speed with a computer plugged into the modem.
Use one of the tools found when you search the phrase:
broadband speed test.

10
•No matter who your service provider is, check Comcast
XFINITY’s Internet Minimum System Recommendations here:
https://www.xfinity.com/support/internet/requirements-
to-run-xfinity-internet-service/
•If you get good speed when a computer is plugged into the
modem, you may have a router problem.
•Some video streaming services get bottlenecked, especially
at busy times like after dinner. See whether you have the
speed problem at less busy times.
•Try connecting your cable modem nearer to where the
coaxial cable comes into your home. This lets you see
whether your home’s cabling is a problem.
•If you’re using a splitter with your cable modem, try the cable
modem without the splitter to see if that helps. If it does, you
may need to get a better splitter, one with a top frequency of
at least 1000 MHz.
•To take full advantage of the 2.5GE Ethernet port on your
MB8611, make sure the computer or router you connect to
also supports 2.5GE. Your MB8611’s 2.5GE port will also
connect to lower speed 1000BT or 1GE Ethernet ports. See
www.motorolanetwork.com/31
What if I'm told that my cable modem isn't approved for
my cable modem service?
That’s probably not true. Leading cable service providers
have a list of certified cable modems, and you can check the
list for your service provider. You can also find information
about certifications at www.motorolanetwork.com/services
Do you have any other questions? We have lots more
information at www.motorolanetwork.com/mentor