The Difference Between UTP And STP Cables

Ethernet comes in several types, each offering a different set of features, protection, data transfer speed, and bandwidth capabilities. When it comes to protection against crosstalk, the two types of ethernet cables are shielded twisted pair (STP) and unshielded twisted pair (UTP). Whether you are using Cat6a ethernet cable, Cat6 ethernet cable, or Cat5e ethernet cable, when it comes to STP and UTP, the performance varies.

Let’s discuss the differences in detail.

STP vs UTP: Protection against EMI

The major difference between the STP and UTP cable is the level of protection against the crosstalk and electromagnetic interference. Nearby air conditioners, motors, generators, office mainstays are common causes of EMI ensuing crosstalk between the conductors that causes increased errors, degradation of data, and slower transmission rates. And this is where STP cables come in handy. These cables are installed in EMI-rich environments as they provide top-notch protection against it.

As a matter of fact, even unshielded twisted pair cables have some protection against electromagnetic interference. However, an STP Cat6 Ethernet Cable will block EMI more effectively than a UTP cable. The reason for this top-notch protection is that STP cables have an extra layer of protection in the shape of thin foil. STP cables are usually used in high-speed applications such as data centers where 10GBase-T networks are used. If shielded cables are properly installed, they bar crosstalk and EMI to the fullest level, ensuring your data integrity and high-speed performance remain intact.

STP vs UTP: Price

Another factor that differentiates an STP cable and a UTP  cable is that shielded cables are relatively much more expensive than their unshielded counterparts. It remains the same irrespective of the category of the cable – be it Cat6 ethernet cable, Cat6a ethernet cable, or Cat5e ethernet cable. The reason for the higher price tag for STP cables is obviously the extra layer of protection. And it is not all about the extra per foot cost of the shielded cable, the connecting hardware of STP cables is also much more expensive.

STP vs UTP: Installation

Thanks to extra layers of protection, shielded twisted pair cables are thicker, and hence more challenging to install when compared with unshielded twisted pair cables. STP cables need to be installed with meticulous care for desired results. STP cables need a drain wire for grounding. However, you can only ground an STP cable if the couplers and jacks in the installation are also shielded. In nutshell, if you want to reap the benefits of STP installation, always use shielded couplers and jacks.

STP vs UTP: Grounding

For superior results, STP cables should be grounded properly. If not done properly, an STP cable will create issues instead of solving them, thus bringing extra headache with it. To ground STP cable properly, you need shielded couplers and jacks (and they will obviously cost you more).

STP vs UTP: Termination Tool

As shielded twisted pair cables have more thickness — thanks to its extra layer of protection — in some cases, STP cables may require larger termination tools for shielded RJ45 connectors.

STP vs UTP: Signal Strength

As STP cables are designed to provide foolproof protection against crosstalk and EMI, they can maintain signal strength at relatively longer distances than unshielded twisted pair, resulting in high level performance and data transfer speeds. Whether it is Cat6 ethernet cable, Cat6a ethernet cable, or Cat5e ethernet cable, the rules remain the same.

STP vs UTP: Installation Environment

UTP cables are preferred in environments where crosstalk or EMI are very little or non-existent. It is because of the reason that UTP cables do not have an extra layer of protection. STP cables are used in environments where there is a lot of crosstalk or EMI; the extra layer of protection in the shape of foil wrapping or copper braid jacket keeps EMI and crosstalk at bay.

Let’s summarize it for you. If you are going to install an ethernet cable in a crosstalk-rich environment, then STP cable should be your preferred choice. If you are going to install an ethernet cable where crosstalk or EMI are very little or non-existent, then you should go with an unshielded twisted pair. There’s no need to buy a STP cable for crosstalk-less environments as it costs way more than UTP cable.