What is Power over Ethernet (PoE)?

Ethernet network cables connect computers and other devices together in a Local area network. Ethernet cabling carries data between the devices on the network. But what if you wanted to connect your WiFi access point or other devices to your network wires? This is where Power over Ethernet (PoE) comes in.

What is Power over Ethernet (PoE)?

PoE gives you the option of using Ethernet network cables to carry both data and the electrical energy that the device needs to operate. This is especially convenient when you do not have access to power points where you want to install network devices such as routers, IP security cameras, smart security systems, etc.  Suppose you need to install a security camera on a fence post in your backyard. If you do not have a power outlet near the fence post, you do not need to worry about running power lines. Just run an ethernet network cable that supports PoE connections. Connect it to your camera and it will run instantly. In the next part, we will look at how PoE works in detail. 

How does PoE work?

The most common way to power a PoE device is through a standard AC to DC adapter, but many PoE devices can use the DC power that is carried over the Ethernet cable. PoE is a standardized version of power over Ethernet (PoE), a feature found on many network switches that supply electrical power to a network device, such as a VoIP phone or access point.  This power comes over the same Ethernet cable that transmits the data, so there is no need for a separate power cable.   If your network is not compatible with PoE connections, you can use a PoE adaptor between your device and the data server/router. You will need to insert the ethernet cable and a power cable into the adapter. And on the other side, connect ethernet cable that is connected to your device.  But in most cases, especially modern tech gadgets such as sound systems and smart LED TVs are equipped with PoE connection adapters so you won’t need to do the extra hassle. 

Different standards and Uses of PoE

Power over Ethernet (PoE) is a technology that allows transmitting data and electric power along a single cable. It is used in various areas, including industrial automation, telecommunication, and especially in the territory of computer networking. PoE allows you to use the same cable to send both data and electric power to an attached computer or device and allows you to install wireless access points and IP phones without the need to install any power line.  The most common PoE standard is PoE. It was standardized in 2003 by IEEE.  There are several other IEEE standards of PoE, including PoE+, and PoE++, each of which has its own unique features and applications. PoE+ was standardized in 2009 and PoE++ was standardized very recently in 2018. 


The various standards of power over ethernet are classified on the basis of their capacity to transfer power in a single port.  PoE, IEEE standard 802.3af, is the most basic standard with a capacity to support up to 15.4 Watts per port. This is used for low voltage devices such as analog security cameras.  PoE+, IEEE standard 802.3at, is rather an enhanced version of the basic standard of power over ethernet. These connections can support power transmission of up to 30 Watts per port. And this power is enough to run devices that require moderate voltage. Such as high-end routers or IP security Cameras.  PoE++, IEEE standard 802.3bt, has two different types. The first one can transmit up to 60 Watts of electrical power and the second type can transport up to 100 Watts of power per port.  This type of advanced PoE is used in flat screens and other high-performance devices. 

Which Ethernet Cables can support PoE connections?

PoE, PoE+, and PoE++ are the most desired ethernet applications. People always prefer ethernet cables that can transport both data and electrical power because it eliminates the need to run separate electrical lines in a network. Almost all of the advanced categories of ethernet cables can support PoE connections. All ethernet network cables, such as Cat5, Cat5e, Cat6, Cat6a, etc can support PoE connections. However, some of the older categories of ethernet cables such as Cat5 may not be able to support PoE++ connections.  The best ethernet cables for PoE connections are the Cat6 and Cat6A cables. They feature bare copper conductors and plenum jackets. Pure copper conductor and plenum rated jacket are important because both power and data transfer over a single cable can lead to heating up of the cable. And the aforementioned features are ideal for preventing such safety crises. 


PoE, PoE+, and PoE++ are popular ethernet applications. They are convenient and cost-effective solutions.