Carnegie Mellon University

UC Phone - Frequently Asked Questions

Unlike traditional copper-wire phones, most VoIP phones use Power over Ethernet (PoE). The power to any PoE devices comes from the network switch connected to the phone cable. If you unplug the phone cable, the VoIP phone does not work.

If an electrical power outage occurs, there is no VoIP phone service. When power is restored and the network stabilizes, VoIP phone service resumes automatically. To request a voice and data outlet, submit an Outlet Estimate Form.

Yes, you can move your VoIP phone to a new office. If you're moving within the same building, no additional action is necessary other than plugging the phone into an Ethernet outlet with a PoE and data connection. Email Computing Services if you need help determining the type of outlet you have, or if you are moving to another building and want to verify that the new location is network-capable.
  •  Verify that the ethernet cable is plugged in to an outlet equipped with PoE and Voice Data.
  • Try another ethernet outlet and cable.
  • Unplug, then plug in again, the ethernet cable.
  • Disconnect any other equipment (e.g., answering machine)

 Verify that your phone and/or Cisco jabber status is not set to DO NOT DISTURB.

  •  Verify that the ethernet cable is plugged in completely.
  • Try another ethernet cable.
  • Try another ethernet outlet.
Verify that you entered the number "9 before dialing the number, if you are forwarding your calls to an outside number.