Category Archives: Copper Networks

Horizontal Cabling: Choose the Right Copper Cable

Copper-based cabling has held the dominate position as the most prevalent horizontal cable medium for years. The reason of this can be partly explained by the fact that copper cable is inexpensive and easy to install. Additionally, the networking devices associated with copper cabling are less costly compared with their fiber optic counterparts. Copper cable comes in a dazzling array of types, and since cable type determines the network’s topology, protocol, and size, understanding the features of each copper cable is necessary for the installation of a successful and robust network.

Copper Cable Types at First Glance

By far the widely installed and most economical copper cable today is twisted-pair wiring. In this form of wiring, two conductors are wound together (“twisted”) for the purposes of canceling out electromagnetic interference (EMI) from external sources, and crosstalk from neighboring conductors. Unshielded twisted pair (UTP) and shielded or screened twisted pair (STP or ScTP) are the two primary varieties of twisted pair on the market today. Screened twisted pair (ScTP) is a variant of STP. Next, we will focus on the characteristics and possible applications of them.

Unshielded Twisted Pair (UTP)

Unshielded twisted pair (UTP) copper cable has been used in telephone systems for many years. And it was also intensively applied in local area networks (LANs) since late 1980s. UTP cabling typically has only an outer covering (jacket), which covers one or more pairs of wire that are twisted together. The lack of shielding enables a high degree of flexibility and durability, lower cost and simpler installation of UTP. During the past years, the bandwidth capabilities of UTP are consistently being improved, making it popular especially in computer networking. Four-pair UTP cables are often used for horizontal cabling, while multi-pair (25-,50-, or 100-pair) UTP cable is more commonly seen in backbone cabling.

UTP copper cable

Features of UTP are listed below:

  • Four-pair cables are typically used for horizontal cabling. Higher pair counts are often used for backbone cabling.
  • Its conductors are not surrounded by a metallic shield to prevent electrostatic or electromagnetic coupling.

UTP cable

Shielded Twisted Pair (STP)

Shielded twisted-pair copper cable has a metallic shield which significantly reduces the instances of interference-related network problems. Though more expensive to purchase and install than UTP, STP offers some distinct advantages: it is less susceptible to outside electromagnetic interference (EMI) than UTP cabling since all cable pairs are well shielded. As with UTP, four-pair cables are typically used for horizontal cabling. When it comes to STP, four-pair cables are offered in two versions:

STP and ScTP copper cable

Four-Pair Screened Twisted-Pair (F/UTP)

F/UTP (also referred to as ScTP) copper cable has an outer metal shielding covering the entire group of copper pairs. This type of shielding protects the cable from external EMI; however, the shield and drain wire add cost as well as size. The shield and drain wire also require bonding and grounding. F/UTP is recommended for use in hospitals, airports, or government/military communications centers.

F/UTP

Four-Pair Shielded Twisted-Pair (U/FTP)

U/FTP (also referred to as STP) copper cable includes metal shielding over each individual pair of copper wires. Besides protecting the cable from external EMI, U/FTP provides better near end crosstalk performance than F/UTP. However, the multiple shields also add more cost and size. Like F/UTP, the shield and drain wire require bonding and grounding.

U/FTP

Should I Choose Unshielded, Shielded, or Screened Copper Cable for Horizontal Cabling?

Network managers and cabling infrastructure designers are constantly in the dilemma to choose between these copper cables. Here we offer a solution for your reference.

For typical office environments, UTP cable always serves as the best choice (until fiber network components drop in price). Most offices don’t experience anywhere near the amount of electromagnetic interference (EMI) necessary to justify the additional expense of installing shielded twisted-pair cabling.

As for environments like hospitals and airports, it would be more beneficial to apply a shielded or screened cabling system. The deciding factor seems to be the external field strength. If the external field strength does not exceed three volts per meter (V/m), good-quality UTP cabling should work fine. If the field strength exceeds three V/m, shielded cable will be a better choice.

Conclusion

We have illustrated the characteristics and possible uses of different types of copper cable in this article. When it comes to horizontal cabling, your choice should base on the specific cabling environment and condition. Hope what we discussed here could help you to make the right decision.

Ethernet Patch Cable Wiring Guide

Ethernet patch cable has already become a ubiquitous part of our everyday experience. It is generally used for connecting virtually all networking components, providing a flexible and cost-effective way of transmitting voice, data, and multimedia over integrated networks. When dealing with Ethernet patch cables, we sometimes get confused regarding patch cable wiring schemes and when they should be employed. So this article will try to shed some light on this commonly confused subject.

ethernet patch cable

Ethernet Patch Cable and Wiring Standard

Since the wiring scheme of different Ethernet patch cable varies, we’ d better get to know the categories of it as well as its wiring standard. Basically, Ethernet patch cable comes in two types: straight-through cables and crossover cables. As for the wiring standard, there existing T568A and T568B defined in the ANSI/TIA-568-C.2 standard for 4-pair (8-position, 8-conductor) RJ45 interfaces. When used in traditional fashion, there is no functional difference between patch cords with T568A or T568B wiring standards. Both wiring standards are acceptable and are essentially interchangeable. The only difference between T568A and T568B specification is the orientation of the green and orange wire pairs.

T568A-T568B-ethernet-cable-wiring-standard

Ethernet Patch Cable Wiring Scheme

In the previous part, we have mentioned the common types of Ethernet patch cables. So next we will further explain their features and illustrate the wiring scheme of each in details.

Straight-Through Cables

Straight-Through cables get its name due to the fact that both of its ends are configured in the same way. This kind of Ethernet patch cable often adopts the same wiring standard: either T568A or T568B layout. Which means out of the 8 pins on both ends of an Ethernet cable, each pin connects to the same pin on the opposite side. Most Ethernet patch cables on the market are straight-through cables, and they are typically used to connect unlike devices, such as connecting a router to a hub, a computer to a switch and a LAN port to a switch, hub or computer.

straight-through ethernet patch cable

Crossover Cables

Judging from the physical appearance, crossover cables just resemble that of the straight-through cables. However, the difference actually lies in the order that the wires are arranged: the send and receive pairs in this cable are crossed from one module plug to the other. Crossover cables use two different wiring standards: one end uses T568A wiring standard, while the other applies T568B wiring standard. This Ethernet patch cable is preferred for direct connection between the same devices: a PC to another PC, a hub to hub or switch to switch.

crossover ethernet cable

How to Distinguish Ethernet Patch Cable?

Knowing the difference between the two types of Ethernet patch cables is proved to be useful, especially when connecting them to various components. Let’ s see how to efficiently identify each.

The easiest way to tell what kind of Ethernet patch cable you have is to look at both of its ends together. If both cable ends are configured according to the T568A or T568B standard for both connector ends, then the cable is a straight-through patch cord. But if the patch cable is wired according to the T568A standard at one end, and the T568B at the other end, the cable is a crossover cable. Crossover cables sometimes have orange or yellow sheaths to make them easier to identify.

ethernet network cable

Conclusion

Ethernet patch cable facilitates our life in various aspects, and it also has played a significant role in the development of generic and structured cabling system. I hope this article could help to eliminate any confusion with regard to the features and wiring schemes of different Ethernet patch cables. FS.COM offers a wide range of Ethernet cables (Cat5e/Cat6/Cat7) and accessories. For more information and tutorials, visit www.fs.com.