Power over Ethernet

PoE802.3at802.3af802.3btMDI powerPoE+Power over Data Lines (PoDL)Power-over-Ethernet
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 PhoneIP PhonesEthernet-based phone
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.
Power source - a battery or DC/AC source; some VoIP phones receive electricity from Power over Ethernet

IP camera

IP camerasnetwork cameracameras
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.
Power over Ethernet (PoE) to supply power through the ethernet cable and operate without a dedicated power supply

2.5GBASE-T and 5GBASE-T

2.5GBASE-T2.5 Gigabit Ethernet2.5GBASE-T, 5GBASE-T
The standard introduces two additional power types: up to 55 W (Type 3) and up to 90-100 W (Type 4). Each pair of twisted pairs needs to handle a current of up to 600 mA (Type 3) or 960 mA (Type 4). 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-poweredphantom poweringpowered
This is similar to the phantom power technique commonly used for powering condenser microphones.
Power over Ethernet

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.
Power over Ethernet and Power over Ethernet Plus promotes the current capabilities of IEEE802.3at-2009, as well driving consensus with efforts to extend the power delivery and port-level resiliency capabilities of IEEE802.3at in the Ethernet community.

Category 5 cable

CAT5Category 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

switchesswitchnetwork switches
A mini network switch installed in distant rooms, to support a small cluster of ports from one uplink cable. (Mini-switches do not usually provide PoE on their output ports.) (Many modern VoIP phones include a two-port mini-switch that can provide a network connection for a nearby computer.) 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 group802.3 standards committee
Three of them have been standardized by IEEE 802.3 since 2003.

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

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

Ethernet over twisted pair

10BASE-T10BaseT10/100/1000
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), or two phone lines, or a second 10BASE-T or 100BASE-TX connection.

Category 3 cable

Cat 3Category 3Cat-3
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

wiredJabbernetworking
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.
Power over Ethernet (PoE)

Cisco Discovery Protocol

CDP
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).
The information contained in CDP announcements varies by the type of device and the version of the operating system running on it. 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

center-tappedcenter-tapped transformercentre tap
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

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

Lithium-ion battery

Li-ionlithium-ion batterieslithium-ion
This enables higher power for applications like PTZ cameras, high-performance wireless access points, or even charging laptop batteries.