PoE

Stands for "Power over Ethernet." PoE provides electrical current over an Ethernet connection. It powers electronic devices via Ethernet cabling without the need for batteries or a wall outlet.

Multiple PoE standards exist, but they all provide both data and electrical power over a single cable. One method, known as "Alternative A," uses the same wires within the Ethernet cable to transmit power and data. "Alternative B" uses one set of wires for sending power and another set of wires for transmitting data.

Technically, the PoE standards are defined as a subset of the IEEE 802.3 collection of standards. Examples include:

  • 802.3af (2003) - supports 15.4 watts
  • 802.3at (2009) - a.k.a "PoE+ or POE Plus;" supports 25.5 watts
  • 802.3bt (2018) - Type 3 supports 55 watts; Type 4 supports 90 watts

In order to power a device via Ethernet, a PoE adapter is required. This device, also called an "Ethernet injector," plugs into a standard power outlet and provides power to one or more Ethernet ports. A broad range of PoE devices exist, including:

  1. VoIP phones
  2. Wireless access points
  3. Audio amplifiers
  4. Lighting controllers
  5. Security cameras
Updated May 17, 2017

Definitions by TechTerms.com

The definition of PoE on this page is an original TechTerms.com definition. If you would like to reference this page or cite this definition, you can use the green citation links above.

The goal of TechTerms.com is to explain computer terminology in a way that is easy to understand. We strive for simplicity and accuracy with every definition we publish. If you have feedback about the PoE definition or would like to suggest a new technical term, please contact us.

Want to learn more tech terms? Subscribe to the daily or weekly newsletter and get featured terms and quizzes delivered to your inbox.

Sign up for the free TechTerms Newsletter

How often would you like to receive an email?

You can unsubscribe or change your frequency setting at any time using the links available in each email.

Questions? Please contact us.