Word of the Day: Power over Ethernet (PoE)

Word of the Day Daily updates on the latest technology terms |April 2, 2018

Power over Ethernet (PoE) Power over Ethernet (PoE) is a technology for wired Ethernet local area networks (LANs) that allows the electrical current necessary for the operation of each device to be carried by the data cables rather than by power cords. Doing so minimizes the number of wires that must be strung in order to install the network. PoE was originally developed in 2003 to support devices like Wi-Fi access points (APs). PoE made AP installations easier and more flexible, especially on ceilings. For PoE to work, the electrical current must go into the data cable at the power-supply end, and come out at the device end, in such a way that the current is kept separate from the data signal so that neither interferes with the other. The current enters the cable by means of a component called an injector. If the device at the other end of the cable is PoE compatible, then that device will function properly without modification. If the device is not PoE compatible, then a component called a picker (or tap) must be installed to remove the current from the cable. This "picked-off" current is routed to the power jack. Equipment built to the 2003 standard initially delivered enough power for most APs, but could not provide enough power for other types of mounted technology, such as video surveillance cameras. Over the years, the Institute of Electrical and Electronics Engineers (IEEE) and several vendors have attempted to address the power issue, but there have always been problems with interoperability. The IEEE will be solving the problem by releasing a new standard that supplies power through all four wire pairs in a Cat5 cable.    IEEE 802.3bt, also known as Next Generation PoE, can supply enough power to support LED lighting, kiosks, terminals and a variety of other devices, including security-card readers. It also defines a way to supply two different power levels simultaneously. Now that an industry standard is finally in place once again, it's expected that PoE usage will continue to grow and play an important role in the Internet of Things (IoT). Quote of the Day "There are several different PoE standards and each standard provides a different maximum per-port watt output. Therefore, it's important to know how much power your end devices actually require." - Andrew Froehlich   Trending Terms Ethernet NBASE-T Ethernet VoIP phone IEEE Standards Association optoisolator 802.3   Learning Center Demands of the edge drive IEEE 802.3bt standard The new IEEE 802.3bt standard targets enhanced efficiency for Power over Ethernet to support the growing demands of network edge devices, such as point-of-sale terminals. Seven criteria to consider before evaluating campus LAN switches Establishing what capabilities you will need before you begin researching specific campus LAN switches can save you time and money. Arista Networks' ultralow-latency switches offer high performance Arista Networks offers ultralow-latency switches for a variety of vertical markets, including finance, government, and media and entertainment. A look at Dell switches that can support networks of all sizes Smaller networks and campus environments can benefit from a variety of Dell switches that offer improvements in performance and port density. Dell's new multigig campus switches built for wired, wireless LAN Dell has introduced two multigigabit campus switches that can run the network operating system of Dell or its partners. The N series switches go on sale in the spring. Writing for Business There are a number of methods you can use to capture VoIP calls ___ a LAN. A. off B. off of Answer   Stay In Touch For feedback about any of our definitions or to suggest a new definition, please contact me at: mrouse@techtarget.com   Visit the Word of the Day Archives and catch up on what you've missed!   FOLLOW US About This E-Newsletter This e-newsletter is published by the TechTarget network. To unsubscribe from Whatis.com, click here. Please note, this will not affect any other subscriptions you have signed up for. TechTarget, Whatis, 275 Grove Street, Newton, MA 02466. Contact: webmaster@techtarget.com Copyright 2018 TechTarget. All rights reserved.