Power over Ethernet

PoE802.3at802.3afIEEE 802.3afIEEE 802.3at802.3btMDI powerPoDLPoE plusPoE+
Power over Ethernet or PoE describes any of several standard or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling.wikipedia
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VoIP phone

IP phoneSIP phoneIP Phones
This allows a single cable to provide both data connection and electric power to devices such as wireless access points, IP cameras, and VoIP phones.

IP camera

IP camerasIP video surveillancenetwork camera
This allows a single cable to provide both data connection and electric power to devices such as wireless access points, IP cameras, and VoIP phones.

2.5GBASE-T and 5GBASE-T

2.5GBASE-T2.5 Gigabit Ethernet5GBASE-T
Additionally, support for 2.5GBASE-T, 5GBASE-T and 10GBASE-T is included.
Unlike the preceding 10GBASE-T standard, equipment manufacturers have indicated their intention to implement 802.3at type Power over Ethernet on certain types of NBASE-T switches.

Phantom power

Phantom poweringphantom-poweredPhantom voltage
This is similar to the phantom power technique commonly used for powering condenser microphones.

Ethernet Alliance

Advocates of PoE, like the Ethernet Alliance, point out that quoted losses are for worst case scenarios in terms of cable quality, length and power consumption by powered devices.

Category 5 cable

CAT5Cat 5Cat 5e
For 10BASE-T and 100BASE-TX, only two of the four signal pairs in typical Cat 5 cable are used. The standards require category 5 cable or better for high power levels but allow using category 3 cable if less power is required.
Through the use of power over Ethernet (PoE), power can be carried over the cable in addition to Ethernet data.

Network switch

switchesswitchEthernet switch
Power is supplied as a common-mode signal over two or more of the differential pairs of wires found in the Ethernet cables and comes from a power supply within a PoE-enabled networking device such as an Ethernet switch or can be injected into a cable run with a midspan power supply.
A modern switch may implement power over Ethernet (PoE), which avoids the need for attached devices, such as a VoIP phone or wireless access point, to have a separate power supply.

IEEE 802.3

802.3802.3 working groupIEEE 802.3-2008
Three of them have been standardized by IEEE 802.3 since 2003.

Link Layer Discovery Protocol

LLDPIEEE 802.1AB802.1AB LLDP
Link Layer Discovery Protocol (LLDP) is a layer-2 Ethernet protocol for managing devices.
LLDP is used to advertise power over Ethernet capabilities and requirements and negotiate power delivery.

PowerDsine

PowerDsine, acquired by Microsemi in 2007, has been selling midspan power injectors since 1999 with its proprietary Power over LAN solution.
Its initial products were Ringing (telephony) generators, and it also developed xDSL Remote Power Feeding Modules, before inventing Power over Ethernet's (PoE) precursor Power over LAN.

Microsemi

Microsemi Corporationacquiredmicrosemiconductor
PowerDsine, acquired by Microsemi in 2007, has been selling midspan power injectors since 1999 with its proprietary Power over LAN solution.

Ethernet over twisted pair

10BASE-T10BaseT10/100
Power over Ethernet or PoE describes any of several standard or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling.
The spare pairs may be used for power over Ethernet (PoE), for two plain old telephone service (POTS) lines, or for a second 10BASE-T or 100BASE-TX connection.

MikroTik

MikrotīklsRouterOS
Passive PoE power sources are commonly used with a variety of indoor and outdoor wireless radio equipment, most commonly from Motorola (now Cambium), Ubiquiti Networks, MikroTik and others.
Almost all models of RouterBOARD devices can be powered by power over Ethernet (PoE), and have a connector for an external power source.

Category 3 cable

Cat 3Cat-3Cat3
The standards require category 5 cable or better for high power levels but allow using category 3 cable if less power is required.
The original Power over Ethernet 802.3af specification supports the use of cable, but the later 802.3at Type 2 high-power variation does not.

Ethernet

Ethernet portEthernet cableEthernet network
Power is supplied as a common-mode signal over two or more of the differential pairs of wires found in the Ethernet cables and comes from a power supply within a PoE-enabled networking device such as an Ethernet switch or can be injected into a cable run with a midspan power supply.

Cisco Discovery Protocol

CDPIndustry Standard Discovery Protocol
The amount of power to be delivered is negotiated between the endpoint and the Cisco switch based on a power value that was added to the Cisco proprietary Cisco Discovery Protocol (CDP).
This information may include the operating system version, hostname, every address (i.e. IP address) from all protocol(s) configured on the port where CDP frame is sent, the port identifier from which the announcement was sent, device type and model, duplex setting, VTP domain, native VLAN, power draw (for Power over Ethernet devices), and other device specific information.

Technical standard

standardstandardsindustry standard
Power over Ethernet or PoE describes any of several standard or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling.

Ad hoc

ad-hocadhocAd hoc query
Power over Ethernet or PoE describes any of several standard or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling.

Electric power

powerelectrical powerelectrical
Power over Ethernet or PoE describes any of several standard or ad-hoc systems which pass electric power along with data on twisted pair Ethernet cabling.

Wireless access point

access pointaccess pointsWAP
This allows a single cable to provide both data connection and electric power to devices such as wireless access points, IP cameras, and VoIP phones. This enables higher power for applications like PTZ cameras, high-performance wireless access points, or even charging laptop batteries.

Balanced line

balancedbalanced pairbalanced circuit
For 10BASE-T and 100BASE-TX, only two of the four signal pairs in typical Cat 5 cable are used.

Differential signaling

differentialdifferential pairdifferential signals
Because twisted-pair Ethernet uses differential signaling, this does not interfere with data transmission.

Center tap

Volts Center Tappedcenter-tappedcenter-tapped transformer
The common-mode voltage is easily extracted using the center tap of the standard Ethernet pulse transformer.

Transformer types

resonant transformerpulse transformeroutput transformer
The common-mode voltage is easily extracted using the center tap of the standard Ethernet pulse transformer.

Pan–tilt–zoom camera

PTZ cameraPan tilt zoom camerapan-tilt-zoom camera
This enables higher power for applications like PTZ cameras, high-performance wireless access points, or even charging laptop batteries.