Power over Ethernet: Taking optimization to new levels

Multitasking is the order of the day — not just for humans, but also for machines and cables. How cool it would be if we have one machine that will make our morning coffee, scrambled eggs, toast, and a cup of fresh orange juice? Now, don’t go to Google right away to buy such a machine, as we are still some years away from such a luxury! But the good news is, we have kick-started this concept of multitasking among machines too, and as a first step, we are enabling this on our cables. Today, we have cables that transmit not just data but also electricity to power the devices that send or transmit data. That’s Power over Ethernet, or PoE for short.

What is Power over Ethernet?

power over ethernet

Power over Ethernet is a technology that enables cables to carry both data and electricity, so an Internet-based device can work by connecting to just one cable instead of one for data and the other for power. Let’s understand this better with the help of a VoIP phone. Currently, we have two cables, one that connects to an electrical socket for power and the other for sending and receiving data. With PoE, a single cable is enough as it provides both electrical power and data. The same idea can be implemented in IP cameras, wireless access points, RFID readers, and more,

But all these devices should be PoE-compatible to tap into this technology. Otherwise, the power from PoE can sometimes damage these devices.

How does PoE work?

In general, network cables have eight wires that are twisted in pairs to form four twisted pairs. Out of these, two are used for data transmission and the remaining two are spare pairs.

Since electric power flows in a loop, PoE treats each pair as a conductor. So, the two spare pairs double up as two conductors to carry electrical current.

Typically, PoE carries a voltage of 48 DC, which is high enough for devices and still safe to transmit and use. If you plan to use both PoE-compatible and non-compatible devices, it is best you have a PoE switch or a midspan that detects whether a particular device is compatible or not, and will send power accordingly.

Why use PoE?

You may wonder why you should even consider Power over Ethernet option when the existing setup is working well. The answer is, PoE is simply better and more resource efficient than traditional cables and they offer a myriad of benefits for your home and organization.

Let’s look at some of these benefits.

Saves resources

At a time when we are marching toward environmental degradation and a severe crunch in the availability of natural resources, it makes sense to tap into every bit of existing resource to get what we want. That’s the fundamental idea of PoE.

When you use this technology, you need only one cable for two connections, so you save on space and resources needed to build an additional cable.


From a financial standpoint, Power over Ethernet is cost effective because you need only one cable instead of two. Over time, this can lead to substantial savings for an organization, especially if your network requires a lot of cabling for Internet-based devices. You get to save money on electrical installations as well.

Power over Ethernet also results in a more compact setup, thereby helping your organization to save on space and the rental and utility costs associated with it.

Reduces time

A related advantage is time-saving. Since network cables do not require a qualified electrician to fix, your devices can be up and running as soon as network cables are in place.


Power over Ethernet offers a ton of flexibility as network cables are easier to install than electrical ones. This means you can set up your device pretty much anywhere. Also, your devices don’t always have to be tethered to an electrical outlet.

Safe and effective

PoE is designed in such a way that the cables are not overloaded. In fact, they are intelligent cables that prevent problems such as incorrect installation, power fluctuations, and data transmission hiccups.

Highly reliable source of power

PoE’s power comes from a universally compatible source that is backed by an uninterruptible power supply. Such a setup makes PoE a highly reliable power source with no voltage fluctuations. This feature makes PoE highly reliable in difficult terrain or in places where power is not readily available.

In addition, the IEEE 802.3af standard ensures that PoEs are reliable in any configuration that supports regular Ethernet.

Now that you know all about Power over Ethernet and its many advantages, let’s see how you can change your existing setup to a PoE-compatible one.

How to convert to PoE?

Power over Ethernet

Switching to PoE is easier than you might think. There are two options to make the switch, and you can choose either one depending on your budget and the current setup of your network.

PoE switch

The easier of the two options is to use a PoE switch. As the name suggests, this is a network switch with built-in PoE injection.

In this option, you don’t have to make any major change to your network. All that you’ll have to do is plug your devices to this switch. If your device is PoE-compatible, it will power automatically. Otherwise, it will continue to act as a regular data cable.

Another advantage with PoE switches is they are available to suit all applications, and they don’t really cost a lot, considering how much you’ll save in cabling.

PoE injector

Another option is to install a midspan or PoE injector in non-PoE cables, so they can get this new capability. These injectors help to upgrade LAN installations, so they can harness the benefits of PoE. Also, this is a versatile option as it requires only fewer PoE ports.

A lesser-known option is to connect IP devices to a PoE splitter, so these devices can tap into PoE’s electricity.

So far, we have seen all about PoE and its installation. Before you jump in though, it is important to know the limitations as well.

Limitations of PoE

The limitations or drawbacks of PoE are:

  • The 100-meter length of Ethernet cables is restrictive and can impact where or how you place your device. With Power over Ethernet, you don’t have the same location convenience as traditional cables.
  • If devices need a much lower power than 48 volts, you have to look for an alternate power source and this diminishes the need for PoE cables.

PoE cables are the next generation cables that transmit both data and electrical power, so you need just one connection instead of two. Such a cabling results in enormous savings of your time, effort, money, and the resources needed to make additional cables. It is also safe and effective and works well for all PoE-compatible devices.

Have you used Power over Ethernet? If so, please share with us your thoughts and experience, so it can benefit our large community.

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