Power over Ethernet (PoE) has become the colloquial term used to describe any technology that allows an Ethernet device to transmit and receive data, as well as receive power over the same cabling. The benefits of using the same cable for both data and power are numerous. It allows power to be delivered to small devices without having an electrician wire new circuits or a transformer to convert AC to DC — also referred to as a wall wart. It can also reduce the weight and cost of deployments, and when using standardized technology, it ensures a high level of safety.
However, when it comes to how power over Ethernet works from a user’s standpoint, the general term “PoE” could actually represent any number of different, incompatible technologies, which has led to considerable market confusion. To help overcome this turmoil, the Ethernet Alliance, an industry forum that aims to advance and promote IEEE Ethernet standards, is launching a certification program that will enable manufacturers to complete certification requirements to earn a branded logo. The goal is to provide a simple and easy way for users to identify what PoE products will work with each other and promote interoperability in the marketplace.
The Ethernet Alliance PoE Certification Program, which will launch this autumn, will initially focus on IEEE 802.3af and IEEE 802.3at products, since so many are currently deployed and will continue to be used in the future. The PoE Certification Program will eliminate confusion and interoperability concerns for end users simply by verifying that Power Sourcing Equipment (PSE) and Powered Devices (PDs) will work properly together. All products that successfully pass the specified requirements will receive a certified PoE logo.
An article in Machine Design gives more detail and delves into the history of PoE.