When installing or upgrading your enterprise business's network infrastructure, choosing between shielded twisted pair (STP) and unshielded twisted pair (UTP) cables is an important decision that can impact network performance and costs. Making the right choice ensures your network has a robust foundation to handle your bandwidth needs reliably. In this blog, we'll break down the differences between shielded and unshielded Cat6 cables to help you determine which is the best fit for your business network.

What Is STP vs. UTP Ethernet Cable?

STP and UTP both refer to Ethernet cables using twisted pair wiring. The primary distinction is that STP Ethernet cables contain shielding to provide protection against electromagnetic interference (EMI), while UTP does not have shielding beyond the twisted pair design.

UTP is suitable for lower EMI environments and has been the standard for years due to its lower cost. However, STP provides superior protection against crosstalk and interference in high EMI areas like industrial settings.

What Are the Differences Between Shielded and Unshielded Cables?

Here's a breakdown of the key differences between shielded and unshielded Cat6 cabling:

EMI Protection

Shielded cables have a conductive shielding layer, typically metal foil or braided conductors, that creates an insulating barrier to block external electromagnetic fields from reaching the twisted pairs of wires carrying the data signals. By containing these disruptive fields, the shielding prevents electrical noise from introducing errors or interference into the transmitted data stream.

Unshielded cables lack this protective shielding layer, relying solely on the twisted pair geometry to attempt to cancel out external EMI through opposing inductive effects – an approach that offers significantly less protection, especially where there are high levels of electromagnetic pollution.

Cost

The additional shielding components required for shielded twisted pair cabling result in higher material costs compared to unshielded cables. The incorporation of a conductive foil or braided shielding layer adds an extra manufacturing step and material expense that drives up the per-unit cost of shielded cables. The thicker overall diameter of shielded cables necessitates the use of larger cable jackets and connectors, further increasing expenses.

Unshielded cables offer a more economical upfront option, but this cost savings must be weighed against the performance implications in environments with substantial electromagnetic interference.

Ease of Installation

Shielded cables present greater challenges during installation compared to their unshielded counterparts. The additional shielding layer and bulkier jacket make shielded cables less flexible and more difficult to route through confined spaces or make tight bends without violating minimum bend radius requirements. This can slow down the installation process and increase labor costs, especially in older buildings with limited pathways for new cabling.

Unshielded cables have a thinner and more pliable design, which is generally easier for technicians to pull through conduits, raceways, and other cable pathways while maintaining proper bend radiuses.

Performance

Shielded cable installations provide a clear performance advantage over unshielded cables in environments plagued by high levels of electromagnetic interference. The shielding layer effectively blocks external EMI sources from coupling onto the cable and disrupting the data signals, preventing issues like high bit error rates, frequent packet retransmissions, and throughput bottlenecks that can severely impact network performance. This shielding becomes increasingly crucial as data rates increase and higher frequencies are used, as unshielded cables become more susceptible to electromagnetic noise.

Unshielded cable installations may be sufficient in low EMI environments, but the noise immunity offered by shielded STP cabling ensures reliable gigabit and 10-gigabit data transmission in harsh electromagnetic settings.

When Does Your Business Need Shielded Cables?

Certain environmental factors increase the need for shielded cabling to prevent electromagnetic interference from impacting network performance. Here are some scenarios where your business should choose shielded cable over unshielded:

EMI/RFI Issues

Network cabling systems that contain significant sources of electromagnetic interference or radio frequency interference can benefit from deploying shielded twisted pair cabling. Industrial settings with heavy machinery, motors, generators, and high-voltage equipment produce intense electromagnetic radiation that can easily disrupt unshielded cable runs.

Even in office environments, older electronic devices like laser printers and fluorescent lighting ballasts can be potent sources of EMI that degrade network performance when unshielded Ethernet cables are used. Shielded cables provide vital protection against these interference sources by blocking the electrical noise before it can impact data transmissions.

Temperature Issues

Ambient heat doesn't directly damage twisted pair Ethernet cables, but it does impact their performance capabilities. Once ambient temperatures rise above 68°F (20°C), the maximum supported cable length for all twisted pair Ethernet cabling begins to diminish due to increased attenuation and noise effects. This length de-rating is more severe for unshielded cables than shielded versions. In warm environments like factory floors or non-climate-controlled wiring closets, shielded cabling can support longer runs at the maximum data rate before reaching the maximum length limit.

Outdoor Installations

Any outdoor aerial cable runs are at increased risk from electromagnetic threats like lightning strikes and electrostatic discharge events. A nearby lightning strike can induce high voltages and current spikes on unshielded Ethernet cables, damaging connected equipment and causing prolonged network outages.

The conductive shielding of STP cables helps dissipate these high-energy surges while shunting disruptive electromagnetic pulses away from the signal conductors. When coupled with appropriate surge protection devices, shielded outdoor cabling installations minimize potential service disruptions from atmospheric electromagnetic events.

Shielded vs. Unshielded Cable: Find the Right Fit for Your Business With TailWind

Selecting the appropriate Ethernet cabling infrastructure is critical for ensuring your business network delivers reliable, high-performance connectivity. For typical office deployments with moderate EMI levels and controlled temperatures, unshielded cables can remain a cost-effective option. However, as data rates and wireless device densities continue increasing, enterprises may find that the benefits of shielded cabling provide a future-proof solution to stay ahead of evolving interference challenges.

Not sure which is right for your network cabling system? Having an experienced structured cabling partner like TailWind can help, especially for enterprises managing multi-site networks. TailWind provides responsive, on-site structured cabling services from more than 3,000 dispatch points across the U.S. and Canada. Our experts ensure your cabling is properly specified, installed, and supported – so you’ll never have to worry about wiring for your business. Reach out to TailWind today to get started.