Power over Ethernet (PoE) in 2023: What Is It, Types & How It Works

Refers to the transmission of electrical power to compatible devices. This is possible through the same network cable that allows connection to local area networks.

This standard has been around since 2003 and was an important change.

It is designed in such a way that it does not impede optimal connectivity and does not reduce performance. This allows users to be able to safely use devices that are compatible with the PoE standard.

As we can see, the network cable has two main functions: data transmission and power supply. Thus we avoid having to use two different ones.

Not all types of PoE are the same. We are going to see which are the main standards that we can use and what general specifications each one has.

The uses, as we will see, also vary from one to another. However, the basis of operation will be the same and will allow the use of a network cable as well so that it can pass power.

• PoE as IEEE 802.3af standard – PoE has become a standard under the name IEEE 802.3af. The maximum output power from the power supply is 15.4 Watts.
  
  It is possible to feed static security cameras (those that do not move from side to side, or up and down). It can power any device that requires a low level of electrical power, and that logically is compatible with the PoE standard.
  
  

• PoE+ o 802.3at – As a standard, it is called IEEE 802.3at. Differently, this one has 30 Watts maximum output power, but 25.50 Watts is the average power received. Likewise, it can feed devices that need more power. Some of the devices that we can feed our simultaneous triple-band access points, biometric sensors, and any type of LED screen.
  
  
  
• PoE++ o 802.3bt – The standard has been improving over the years, mainly because it seeks to feed the different devices that exist on the market with greater electrical power.

Consequently, PoE++ was born, which is subdivided into two types: Type 3 and Type 4.

They are referred to as Type 3 and Type 4 since the earlier PoE and PoE+ standards are also known as Type 1 and Type 2, respectively.

One of the direct objectives of this standard is to eliminate the need to install equipment for power supply.

Consequently, there is a significant saving in the costs of implementing a network.

Likewise, people who are not exactly involved in networks can perceive the advantages of using PoE.

It will be much easier for anyone to know that through a single cable, they are already managing to provide electricity to a device (IoT equipment, for example) and, in turn, connectivity.

In the long run, you will not have to think at all about which cable to disconnect from the current, which is from the network, and which one you should not disconnect.

This is why we’ve enlisted Power over Ethernet (PoE) advantages:

1. It can save us considerably in cost as you don’t need a separate electricity supply, so in terms of labor for installation, you would not need an electrical professional to do it.

2. They can be enabled to turn off automatically at night, also to restart remotely, and collect relevant information from devices that are connected to the network.

But not everything is perfect. So, we’ve also enlisted Power over Ethernet (PoE) disadvantages:

1. State-of-the-art PoE power supplies also suffer from certain energy insufficiency, in particular, as we already mentioned before, they can perfectly supply, for example, standard cameras with movement, but they cannot provide enough electrical power to high-consumption devices such as network PTZ camera.

2. Depending on the method we use, if a single power supply or switch is usually connected to several powered devices, the moment any PoE has a problem, all devices will stop working.

3. It can be somewhat expensive, since, to mitigate the risk of the aforementioned, we could choose to supply power to different devices through independent devices for each one, but this would considerably increase the cost of other types of solutions available on the market, so it is usual to examine even a combination between PoE and some other available solution.