To install a new modem and router using an Ethernet cable, you need the following items.

  • Modem
  • Router
  • Two Ethernet cables
  • Coaxial cable
  • Modem and router power cords

Before installing your new modem, you need to disconnect your old modem from your cable wall outlet and computer first.


  1. Connect one end of the coaxial cable to the cable wall outlet.
  2. Connect the other end to the modem.


  1. Connect the modem power cord into an electrical outlet.
  2. Connect the other end to the modem.

    Note: Most modems are always on and don't have a power switch. If there is a power switch on the modem, turn it on.


  1. Connect one end of one Ethernet cable into the back of the modem.
  2. Connect the other end into the Wide Area Network (WAN) port on the router.


  1. Connect the router power cord into an electrical outlet.
  2. Connect the other end to the router.


  1. Connect the second Ethernet cable into port 1 on the router.
  2. Connect the other end into the back of the computer.


Check the modem and router lights to confirm they have power, and connect to the network and your computer. To learn more about which lights should be on for your specific devices, refer to the user guides

Equipment check

Before you get started, check that you have all the proper equipment. If you purchased or leased your modem through CenturyLink, then you have a kit that includes:

  • your CenturyLink modem and its AC power adapter
  • a green telephone cord
  • a yellow Ethernet cable
  • a couple of DSL filters
  • and the installation guide

You also need your computer turned on and ready to go.

Note: Even if you received your modem kit early, your service probably isn't active yet. It's best to wait until after 8:00 pm on your scheduled service day. If you try to activate your modem sooner, you may run into problems.

Connecting your modem

Step 1: Find a good place for your modem

Where you decide to place your modem can affect its performance. As with most electronic equipment, pick a place that has good air circulation and that won't get too hot. If electronic components get excessively hot, they don't typically work as well and may break.

If you're using a wireless modem, ideally, place it in a high, central location that allows for better range of coverage. Also, you can get the the best speed and performance from your modem by not placing it near:

  • cordless phones
  • computer monitors (minimum 3 ft. away)
  • wireless video cameras
  • windows (minimum of 3 ft. away)
  • Bluetooth devices
  • microwaves (minimum of 10 ft. away)
  • reflective surfaces (e.g. windows, mirrors, water)
  • large amounts of water (e.g. fish tank, water cooler)
  • reinforced concrete
  • metal partitions, fixtures, ceilings
  • sprinklers, and pipes

Step 2: Power up your modem

Once you have found the perfect place for your modem, it's time to give it some power. Start by connecting the power cord to the modem and plugging it in.

You might notice that there is no power switch on the modem. Although some modems have a power switch, some don't.

  • If your modem doesn't have a power switch, then it is automatically turned ON when you plug it in.
  • If your modem has a power switch, make sure it is in the ON position.

Give the modem 1 to 2 minutes to boot up. When it's ready, you'll see the POWER indicator light up ON the front of the modem. This is a good time to make sure your computer is ON and ready to go.

Modem? Router? Which is it? 

It can be both! Although modems and routers are different, for ease and convenience, most CenturyLink modems have a built-in router. Additionally, depending on the model, your device may be wireless capable.

Step 4: Connecting cords and cables

Now, let's move on to connecting the cords and cables.Your kit comes with a green phone cord and a yellow Ethernet cable. Let's work with the phone cord first. 

Plug one end of the green phone cord into the green port in the back of the modem, labeled either DSL or LINE.Plug the other end into the phone jack in your wall. When you hear it click, you know you've inserted it correctly.

A couple of important things to avoid:

  • This is the only phone line where you don't want to use a filter.
  • It's important not to connect the green phone cord to the modem port labeled PHONE.

IMPORTANT: The modem has a built in filter, so there's no need to use a filter on the line that connects your modem to the wall jack. In fact, if you do, you'll have problems.

Ok, now on to the yellow Ethernet cable. The Ethernet cable may look like a phone cord, but if you examine it closely, you'll see it's slightly bigger. To keep things simple during the setup, even if your modem and computer are wireless capable, we recommend that you use the Ethernet cable to connect your computer to the modem.

If your modem has multiple yellow Ethernet ports, you can safely use any them. The additional ports allow you to connect additional computers or peripheral equipment like a printer.

Plug the other end of the yellow Ethernet cable into the Ethernet port on your computer. The location varies by computer model. Examine your computer for a port. It looks sort of like a phone jack except it's slightly bigger.

If you've correctly connected the Ethernet cable, then the lights around the Ethernet port on your computer will light up.

What does a PC Ethernet port look like? 

If you are using a PC, the port might show a symbol that looks like 3 or 5 squares branching off a single line.

What does a Mac Ethernet port look like? 

If you are using a Mac, the port symbol looks like 3 dots between 2 brackets.

Step 5: Double check your modem

At this point, before starting your service activation, it's a good idea to double check your modem.

  • Your modem is plugged in and has power.
  • The green phone cord is connected from the jack (no filter) to the modem (DSL or LINE port).
  • The yellow Ethernet cord is connected to the modem and computer.
  • The lights on the front of your modem show the following:
    • POWER light is solid green.
    • DSL light is solid green.
    • Internet or INT light icon (either be solid or flashing).
    • Ethernet port number light is green.

If the lights aren't lit up properly, then double check all of your connections and give it a couple of minutes. If after a few minutes the lights still aren't correct, then it's probably best to contact CenturyLink Tech Support.

Ever wonder what the color and behavior of the lights on your modem mean? Learn more about your modem.

Modem and service activation

Once you've set up your modem, you won't be able to surf the Internet until you go through the activation steps. This process authorizes your modem to access your CenturyLink High-Speed Internet service. It's a fairly easy, step-by-step process that usually takes about 15 minutes to complete.

To get started, go to your computer and open a web browser, such as Internet Explorer or Firefox.

When you open the browser, you'll immediately see the welcome screen. You'll know that you're in the right place when you see the CenturyLink logo and a message that reads "welcome. let's get started."

Click the green Next button to begin!

If you don't see this screen, then you might want to try manually navigating to "" by typing it into the address bar of your browser.

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