Shielded vs Unshielded Cable: What are the Similarities and Differences?

FACTS CHECKED BY  Jose George​

For a network to be built and connected throughout the area, using cable is a must. There are several types of data cables available across the market, and each has its features and comes in handy for different needs. One of all is the Twisted Pair cable, which is further divided into Shielded vs Unshielded Cable. What is the difference? Let’s find out.

Table of Contents

What is Twisted-Pair Cable?

There are four pairs of wires inside the insulation jacket in a twisted pair cable that are twisted with each other. However, each pair has a different number of twists per inch to ensure less electromagnetic interference from the adjacent pairs of wires. Besides, the twisting of the cable gives signal noise immunity.

The tighter the twists inside a cable, the more significant the transmission rate. Thus, higher is the cost of the wire cable as well.

In a LAN, you may be using the same or different types of cables simultaneously, and the usage of other lines does not raise compatibility issues. Instead, you need to select the class based on the needs of the network’s protocols, topology, and the area it is covering.

A twisted pair of cables come in two types

  • Unshielded Twisted Pair UTP cable
  • Shielded Twisted Pair STP cable

Between the two categories, a Shielded pair cable may provide you with more reduction in electromagnetic interference. Yet, unshielded is the most popular option to set up a school network.

A simple twisted pair cable

Caption: A simple twisted pair cable

Unshielded Twisted Pair (UTP) Cable

Unshielded Twisted Pair Cable is a twisted cable in which each wire is only wrapped with a foil. There is no additional layer of other material, thus no added protection.

What are the categories of an Unshielded Cable?

Following are the standard categories of a UTP cable.

CategorySpeedUse
11 MbpsFor Voice Only (Telephone Wire)
24 MbpsLocal Telephone Cables (Rarely used)
316 Mbps10Base Type Ethernet
420 MbpsToken Ring (Uncommon)
5100 Mbps (2 pairs)100Base Type Ethernet
1000 Mbps (4 pairs)Gigabit Ethernet
5e1,000 MbpsGigabit Ethernet
610,000 MbpsGigabit Ethernet

What type of connector does an unshielded twisted pair (UTP) cable uses?

Unshielded twisted pair (UTP) cables use the RJ45 connector to terminate its ends. RJ stands for Registered Jack. Thus, you know that a connector is made on the standards devised in the telecommunication industry. These standards narrate the way every wire will connect to each pin of the connecting switch. Moreover, RJ45 is a plastic telephone-style connector that you can connect to a slot in only one way.

 Crimped red Ethernet connector on unshielded twisted pair cable

Caption: Crimped red Ethernet connector on unshielded twisted pair cable

Where do we need Unshielded Twisted Pair (UTP) cables?

Unshielded cables are the most common type of network cables as they are inexpensive yet flexible and light-weighted. Hence, you can use them for setting the networks in places where you know there will be less external noise to interrupt the signals.

You will likely get shorter UTP cables since unshielded cables are standard in houses, offices, and other small network areas. For example, homes and offices may need a 100 ft. Cat6 cable of Ethernet and it will be enough for them. However, in the places like hospitals and airports, where you set up large networks, you have to go for long shielded twisted pair cable.

Category 6 unshielded twisted pair cable

Caption: Category 6 unshielded twisted pair cable

Shielded Twisted Pair (STP) cable

Shielded Twisted Pair (STP) cables have every individual wire wrapped into a foil. Yet, a single layer is not enough, so an additional protection layer covers the whole cable again. The double layer of foil helps lessen the electromagnetic radiation or any other technical issues that may hinder the quality and integrity of the signals.

electrically shielded cable with copper

Caption: electrically shielded cable with copper

How many types of STP configurations are available?

You can find Shielded Twisted Pair (STP) cable in three types of configurations:

  1. Foil is wrapped around every individual pair of wires
  2. A Braid shield or a foil is wrapped around all the wires as a group (added layer, second to the outer jacket)
  3. Shield or foil around every single pair. In addition, a shield around all the groups of wires (referred to as double-shielded cable).

Why Use Shielded Cables?

Electromagnetic interference (EMI) or radio frequency interference is the external noise that may interfere with the actual signals traveling in a cable. Also, if it is strong enough, it will temper the communication lines and not allow the two computers to “hear” each other. As the data gets lost, information has to be sent. Again and again, thus, the overall efficiency and speed of the network are lower.

In the places where you expect the electromagnetic interference to be high, you need to use shielded twisted-pair cables. It will lessen the noise interference and decrease the error rate due to the loss of information in a connection.

What are the different types of Shielded Twisted Pair Cable?

You can choose from these two types of shielded cables

Braided Cables

Braided cables give about 90% protection from EMI or electromagnetic interference. This type of shielded cable features a mesh of woven copper wires, and it may not provide 100% of shielding, yet it lasts longer than foil shielded cables.

The shielding capacity of a braided cable depends on how the manufacturers weave the wires. For instance, a simple line can shield 70% of the EMI. Hence, if the cable has to remain stationary, the least protection is okay. However, the higher the protection, the greater the cost of the cable.

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Caption: Braided shielded twisted cable

Metal-coated Mylar and Foil Shielded Cable

In foil-shielded cables, there is a thin sheet of either copper or aluminum bonded with polyester to increase the strength of the cable. A metal-coated foil shielded cable can give you up to 100% of EMI protection. It is also referenced as tape shielding. It is a common choice where the environment is noisy, with lots of interference.

Metal coated foil shielded cable

Caption: Metal coated foil shielded cable

Where do we need Shielded Twisted Pair (STP) cables?

Shielded cables are highly used in places where the chances of EMI are higher. Hence, airports and radio stations are the perfect places that use STP cables.

STPs are also applicable in

  • Security systems where you do not want to trigger false alarms due to interrupted signals.
  • Recording studios or public addressing speakers to help balance the audio configuration.
  • Box building applications where every component is working together and can intermix the signals

Shielded vs. Unshielded Cable: SIMILARITIES

Following are a few similarities between the shielded and unshielded twisted pair cables

  • Both use RJ45 connectors
  • They have four twisted pairs of wires
  • you may open the wires through ripcord or special stripping tools
  • You will always use TIA 568 A or B standards to terminate the cables
  • These may have a spline. The spline refers to the internal plastic skeleton that keeps the pairs together. It can reduce attenuation or disturbance between the pairs. Additionally, it can help to kink during installation.
  • Both types of cables may require the same tools for installation
  • Moreover, both cables have the essential functions of delivering the data signals from point A to B

Shielded vs. Unshielded Ethernet Cable: DIFFERENCES

Here are the few differences between the two types

  • Shielded cables are more challenging to install than unshielded cables as the cable is thick
  • STP can cost more per foot and requires special hardware to work accordingly
  • UTP has no additional layer of protection, whereas shielded cables have aluminum foil or braid for added EMI protection
  • STP has an electrostatic drain wire to provide a pathway to static buildup charges, whereas UTP does not have such added features
  • Shielded cables should be properly grounded. On the other hand, unshielded wires do not require an earth connection
  • Moreover, STP need large connectors since the cable is thick
Twisted pair cable

Caption: Twisted pair cable

Conclusion

The two types of twisted pair cables, STP and UTP, differ on whether it has a protected layer or not. In a noisy environment, shielded cables are the first choice to build a network. However, it is not necessary to use STPs everywhere as it is costly. In small networks, you can use unshielded twisted pair cable and still get undisturbed signals. Here at Cloom, we offer help in wire harnessing and cable connection. So, to get your quote, contact us now.