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Does Ethernet Cable Need To Be Shielded? [Why and When]

There are two types of Ethernet Cables for safety purposes. One is Shielded, and another is Unshielded.

Shielded Ethernet Cable provides some extra safety from EMI or Electromagnetic interference. But, there is some confusion around this cable.

But don’t worry; after reading this post completely, you might hardly have any confusion.

So, Does Ethernet Cable Need To Be Shielded?

You don’t need any shield on your Ethernet cable if you don’t have any Electromagnetic interference near you. Shielded Ethernet Cable is a must for areas with high electromagnetic interference.

Like big industries, airports, Radio Stations, Data Centers, and other [FM transmitters and high radiation towers]. These places have high electrical radiation.

So if you run Ethernet Cable in or near those areas, your Ethernet cable will try to catch the EMI (Electromagnetic interference), and thus you’ll have connection issues.

But, for regular usage in our house, we don’t need any shielded Ethernet cable; an Unshielded Ethernet is well enough.

Does Ethernet Cable Need To Be Shielded

How Does the Shield Inside of an Ethernet Cable Work?

To protect against outside Electromagnetic interference or EMI, there is an aluminum foil that covers the wires or twisted pairs inside an Ethernet Cable.

This aluminum foil eliminates the outside EMI and provides a stable connection despite high electrical radiation near your cable.

As we know, aluminum foil works fine as a conductor, reflecting the outside EMI without affecting the signal. But, some radiation still enters because it is hard for the aluminum shield to reflect all the EMI.

But, now the grounding comes into play, the grounded aluminum transfers the remaining EMI to earth, and thus there is no EMI inside your Ethernet wires or conduct.

In this way, the aluminum cover helps run the internet smoothly and efficiently without any issues in such areas.

shielded vs unshielded twisted pairs
shielded vs. unshielded twisted pairs

In this image, you can see that the Shielded Ethernet cable has extra aluminum foil protection. In contrast, there is no protection on Unshielded Ethernet Cables.

Although the 4 twisted pairs or a total of 8 wires inside an Ethernet cable have EMI, it is really low. And here, the twisted wires come into play.

Twisted pairs eliminate the inside radiation from each wire. And it also helps protect against small EMI objects that we all have in our houses.

So that’s the blessing of modern technology.

High EMI Areas You May Suffer from Ethernet Connection

Here I’ve listed some areas with high EMI and perfect places to use Shielded Ethernet cable connections.

  • Airport: In airports, there’re lots of sources of electrical interference. To run an Airport, it is definite to have those types of equipment. So those equipment generates heavy EMI, and thus airports use Shielded ethernet cables.
  • Data Center: Similarly, in data centers, you can find electrical devices everywhere that generate EMI, and so you can find people in those centers using Shielded ethernet cables.
  • Radio Stations: Again, it is also a huge source of EMI; in radio stations, many radio transmitters transmit radiofrequency. So if you’re near a radio transmitter, you can have issues with your wired connections.
  • Big Industries, Factories, and Medical Centers also uses shielded ethernet connection.

Does Shielded Ethernet Provide More Safety?

Yes! Shielded Ethernet cables do provide more safety and security. Suppose you’re in an area with high EMI and running a wired internet connection; you may have issues like crosstalk, connection interruption & others.

So in EMI areas, you need more protection as a shield on an Ethernet cable to have a stable connection and run the Internet smoothly. Also, this shield protects you from many others situations. It is also good for less radiation.

Also, a new type of attack from hackers called “EtherOops” could happen due to EMI, but don’t worry if your cable is not damaged, then you’re safe, and several factors work here. And also, the percentage of that kind of attack is deficient.

Thus, having a shielded ethernet cable is suggested if you’re running a wired internet connection near EMI or RFI areas to stay safe and run the Internet smoothly.

Does Shielded Ethernet Increase the Speed?

When you have Electromagnetic radiation near your Ethernet cable, it slows down your internet speed. In this situation, it is great to have a Shielded Ethernet cable as it can improve your Internet’s speed and overall performance.

But, if you don’t have any EMI or RFI near your cable, it can do the opposite, which can slow down your Internet speed and overall performance. So remember this fact because you might blame your ethernet cable.

So only use a shielded ethernet cable if you have some heavy EMI sources or RFI near your cable. For normal use, UTP is well enough; all of the Ethernet cables are Unshielded that I use in my home.

Does Outdoor Ethernet Need To Be Shielded?

The answer is it depends on how you run your Ethernet cable outside! If you directly bury your ethernet cable, you don’t need any Shielded ethernet cable if there’s no EMI, but you do need a shielded one if your cable is directly exposed to air and an open environment.

Talking about it in detail, when you bury your ethernet cable, the dirt will ground out your cable, thus protecting your cable from many situations. Also, you have to ensure there is no electrical source around your ethernet cable.

Buried Ethernet
Buried Ethernet

So this situation is perfect for using an Unshielded ethernet cable. But you have to make sure you’re using a UV-rated or Weatherproof Ethernet cable, which can be found here on amazon.

Note: Whenever you’re burring your ethernet cable, make sure it is buried in lazy “S” patterns, which will not damage your ethernet cable as the earth moves.

Suppose you’re running an ethernet cable in an open environment, exposed to air, sunlight, and lighting; then you need a shielded ethernet cable. The air can generate ESD, damaging your cable if it is not grounded correctly.

Ethernet in Open Environment
Ethernet in an Open Environment

The temperature swings in an open environment are also a tremendous challenge for your ethernet cable.

To keep your cable safe from temperature swings, you can use a UV-rated Ethernet cable or CMX cable jacket found here on amazon.

Note: You may need lightning surge protections for your Ethernet cable to protect against heavy lightning. It is recommended to use this lightning surge protection to run an outdoor ethernet. You can shop for a lightning surge protector from here.

Should Ethernet Shielding be Grounded?

YES! An Ethernet shielding should be appropriately grounded to eliminate most of the Electromagnetic Radiation [EMI]. If you don’t do it properly, the shield will not work correctly and will work the same as an Unshielded Ethernet cable.

The aluminum foil reflects the EMI, but still, it cannot reflect the complete EMI. So by grounding the aluminum shield, the direction of the EMI changes, and it goes to the earth instead of going inside your cables and affecting badly.

And to ground your shielded ethernet, it is recommended to do the complete process by a pro. Because there are many technical processes involved, I’ll hopefully share a proper guide on how to do it.