New applications coupled with the growth of Internet users are driving the need for increased bandwidth. The 10GbE structured copper cabling system just addresses this demand, which allows the use of the existing equipment and adds the latest communication technologies, contributing to scale the networks to 10 Gigabit speeds and leverage the investment in installed copper cabling infrastructure. For 10GBASE-T data transmission, both shielded twisted pair (STP) and unshielded twisted pair (UTP) copper cabling systems are applicable. This guidance may inspire you about how to choose UTP vs STP Ethernet cables for the 10GBASE-T network.
Moving to 10G Ethernet has a number of choices from 10GbE interfaces including CX4, 10G SFP+, SFP+ direct attach copper (10G SFP+ Cu), and 10GBASE-T. Among them, 10GBASE-T is perceived as a cost-effective solution for broad deployments, which provides 10 Gbit/s connections over unshielded or shielded twisted pair cables over distances up to 100 meters (330 ft).
What is 10GBASE-T? 10GBASE-T is the fourth generation of IEEE standardized BASE-T technologies which all use twisted-pair cabling to provide 10Mbps, 100Mbps, 1Gbps, and 10Gbps data transmission. Since BASE-T devices have used an auto-negotiation protocol defined by IEEE to determine the capabilities supported by the other end of the link, the backward compatibility indicates that the upgrades could be performed one end at a time, allowing a quick and easy incremental improvement of network speed without changing the wiring or upgrades of equipment.
10GBASE-T provides a high-speed networking solution for horizontal copper applications and high-performance networking in the following areas:
Local uplinks, aggregation links, and inter-switch links
HPC (high-performance computing) data centers in new and existing installations
Enterprise server farms/data centers with both new and legacy media
Other applications that can use in-building structured cabling with both new and legacy media
A twisted pair consists of a pair of insulated wires twisted together. This kind of cable twisting helps to reduce noise pickup from outside sources and crosstalk on multi-pair cables. Twisted pair cabling is often used in data networks for short and medium-length connections due to lower costs compared to optical fiber and coaxial cable. Two common types of twisted pairs are—unshielded twisted pair vs shielded twisted pair.
Unshielded Twisted Pair consists of color-coded copper wires but does not include any foil or braiding as an insulator to protect against interference. The cable has four pairs of wires inside the jacket. Each pair is twisted with a different number of twists per inch to help eliminate interference from adjacent pairs and other electrical devices.
The ANSI/TIA-568-C.2 standard states that the category cable must be smaller than 0.354 inches in outside diameter, regardless of whether the cable is shielded or unshielded. UTP cables tend to be larger in diameter than shielded cables because of the use of space and fillers as a barrier against alien crosstalk. Some UTP patch cable designs tend to fall close to the permitted maximum diameter.
Shielded twisted pair contains an extra foil wrapping or copper braid jacket to help shield the cable signals from interference. The additional shielding in the STP cable stops electromagnetic interference from leaking out of or into the cable. STP cable is used to eliminate inductive and capacitive coupling. Twisting cancels out inductive coupling, while the shield eliminates capacitive coupling. Compared to UTPs, STP cables cost more but support higher transmission rates across longer distances, particularly fast-data-rate Ethernet.
Most applications for this cable are between equipment, racks, and buildings. Shielding adds some attenuation to the cable (compared to unshielded), but usually not because in the case of balanced transmission, the complementing signals will effectively cancel out any shield currents, so shield current losses are negligible.
As is known, copper cable suffers from higher signal losses than fiber optic cable. Alien crosstalk is an important performance parameter for copper cables. So what is the Alien crosstalk? Alien Crosstalk (ANEXT) is the crosstalk that occurs between adjacent cables and connecting hardware, which is far severer in the high-speed application than in lower-bandwidth infrastructure. In 10GBASE-T applications, the alien crosstalk limits the data transmission performance over copper cable greatly.
However, 10GBASE-T transceivers can't detect and compensate for noise from adjacent channels, which must be suppressed within the cabling system to ensure reliable data transmission. Cat6a UTP cabling, to reduce alien crosstalk, manufacturers have taken steps in increasing separation between cables and tighter twisted rates or crosstalk suppression within the printed circuit boards as to the connectors. These methods comply with TIA/EIA standard PSANEXT and PSAACRF specifications for reaching 100 meters. Without these improvements, the category 6 UTP system can't meet the alien crosstalk limits required for 100 meters of 10GBASE-T transmission.
In UTP copper cabling, the alien crosstalk will increase when adjacent cables are close proximity, which is indeed a nightmare to many users. Compared with the UTP cabling system, the STP cabling system is able to deliver excellent alien near-end crosstalk performance. For properly installed and bonded STP cabling, foil screens within the cable prevent signals from the coupling. Thus, it reduces alien crosstalk below required performance levels.
STP cable includes a shield around each individual pair. So STP cables are not easy for termination, resulting in more difficult cable management. Because the foil and drain wire in an STP cable must be pulled back and twisted around the cable end prior to termination. And the unused foils should be trimmed. But for UTP cable, it's designed as unshielded, saving time for termination. Thus, the termination takes longer for STP cabling than UTP.
A properly structured grounding process is necessary to protect both personnel and equipment. If 10GBASE-T compliant copper cabling is installed, the integrity of the bonding and grounding system must be sound to realize the full performance of the system.
The UTP cabling connectivity doesn't require complete system bonding. But you should consider the integrity of the grounding of the patch panels and racks to the common grounding point to protect the infrastructure. While for the STP cabling system, bonding cable to the connectivity components is a must to ensure proper performance. For 10GBASE-T data transmission, you should be careful with the implementation of the power and grounding system that the copper data cable system resides in. If the power or cabling system is not properly designed, data rate errors are likely to happen.
Overall speaking, the cost of the STP cabling system is higher than the UTP cabling system. On one hand, STP cable design contains shielding material, which brings more costs for STP cable. While UTP cable and unshielded connective hardware (jacks and patch panels) tend to cost less than their shielded counterparts. On the other hand, during installation, an STP cabling solution will take longer to terminate jack modules and properly bond the structured cabling system which will cost more on installation expenses. The UTP cabling solution is simple to manipulate, bringing quicker termination times and thus reduced cost.
10GBASE-T has expanded the opportunity for 10G Ethernet networking by supporting simpler & cheaper twisted-pair copper cabling. Broad deployment on the 10GBASE-T network will simplify data center infrastructure, making it easier to manage server connectivity and deliver more bandwidth. Since 10GBASE-T has become the predominant choice for many users, it's crucial to decide whether STP vs UTP for your Cat6 or Cat6a cabling. Take performance, termination, installation, and costs into consideration, you'll find it's not difficult to make a wise choice. Most importantly, whether you use STP or UTP cables, just make sure to install high-quality cabling, which will help to reduce long-term replacement and labor costs.