Test your internet at the Network Interface Device

If your internet speed test is slower than you expected, this is a great way to see where the problem is at. The Network Interface is also know as the NID or DMARC.

What is the Network Interface Device (NID)?

  • The NID links the telephone network to the wiring inside your home. It's where our outside wiring meets your inside wiring.
  • NIDs are usually 6" by 9" gray boxes attached to the outside wall of your home. (If you don't see it outside, look in your basement or attic.)

Locate your Network Interface Device (NID)

To test your Internet at the Network Interface, you will need a couple of things:

  1. Use a flat head screw driver to open the "CUSTOMER ACCESS" portion of the telephone network interface (NID).
  1. Locate the test jack that has a wire running to the house, unplug the cord that is connected to the test jack.
  1. Plug one end of the phone cord into the test jack. Plug the other end into the DSL / LINE port on the modem.
  1. Plug the modem into the power. You may need an extension cord for power.
  1. Wait for the DSL light to turn solid green This may take up to 5 minutes. Conect a device to the modem and run another test. If you have any questions, chat with tech support to review your findings.

What's next?

We do all we can to make CenturyLink services perform as you expect, but occasional problems are unavoidable. Start with our Service Troubleshooter for a fast, convenient way to identify and fix common issues. 

If your results aren't what you were expecting or you need more assistance, call or chat with our support team. We're here to help.

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