What Is a PoE Switch and How Does It Work?

Since introduced to the telecommunication field, PoE switches, as a major application of PoE technology, have made great contributions to simultaneous data and power supply over one single Ethernet cable. Nowadays, in the background of the increasing number of IoT projects such as smart cities and intelligent buildings, PoE switches show greater growth potential. This post will demystify PoE switch in a concrete way by clarifying its functions, the benefits and limitations as well as addressing some FAQs about PoE switches.

What Is a PoE Switch and How Does It Work?

What is a PoE switch? PoE switch or power over Ethernet switch is a network switch that applies Power over Ethernet technology. With a PoE network switch, the network connectivity and the power to supply the PD (powered device) can both be efficiently realized over the Ethernet cable. Currently, there are all kinds of PoE network switches filled in the market. Based on the port number, the 8, 12, 24 port PoE switches, 48 port PoE switches are commonly seen in the market. When turning to the control level over the network, unmanaged and managed PoE switches are available.

PoE Switch vs Non-PoE Switch

PoE Switch vs Non-PoE Switch: Why You Need the PoE Switch?

The reason why you need power over Ethernet switches will be obvious when comparing PoE switch vs non-PoE switch. As the most basic switch, the non-PoE switch refers to the switch that is not PoE enabled to supply power for end-users over Ethernet, but can only send data to network devices. To acquire PoE, users have to deploy a midspan power sourcing equipment (PSE) like the PoE injector between the switch and PDs. This injector or other midspan PSEs can add electrical power while receiving data signals from the cable connected with the non-PoE switch, and then deliver both data and power to PDs (Learn more about PoE injector from What Is a PoE Injector And How to Use It?). In this application, the injector or other midspan PSEs will also need a wire for power. However, for a gigabit PoE switch application, things will become easier. For a PoE switch, only one power cable for the switch and one network cable to connect PDs are required. Then the PD can be directly plugged into the PoE gigabit switch port for both data transmission and power supply.

Network Switch and cameras

Based on the working mode of PoE vs. non-PoE switch, the PoE switch brings benefits over the following aspects:


Getting rid of the restrictions of non-PoE switches needing additional PSEs and extension cables, the PoE switches gain great flexibility for users’ network cablings. It enables PDs like IP surveillance cameras to be installed based on where it needs to go. Besides, a combination of PoE switch and wireless technology can even make the cable-free environment be possible.


Without the need to consider additional PSEs and installation locations like a non-PoE switch, the PoE switch simplifies the whole network deployment. In addition, good PoE switches also enable simple network management protocol (SNMP), which provides a simpler way to supervise and manage the switch.


With PoE network switch, there is no need for users to purchase and install additional electrical wires and outlets, which creates significant savings on installation and maintenance costs and time.

However, there are also some limitations on PoE switches you should pay attention to:

Distance Limitation:

The distance that PoE switches can transmit over Ethernet is generally up to 100 meters. For those large campuses, restaurants, and enterprises deploying PoE, the 100-meter distance limitation is a challenge. However, there are still methods to extend PoE range—devices such as power extenders or powered fiber cables. For more information, refer to Powered Fiber Cables: Solution for Extending POE.


If you require high power over PoE networks, you are bound to make sure the power capacity of your PoE switches meets your needs because there is a power limitation based on the PoE standards and PoE Wattage.