Comparing UTP and STP Copper Cables

četvrtak , 22.12.2016.

Many telecom professionals anticipated that copper cable would eventually be replaced by the fiber optic cable owing to its poor performance in higher-bandwidth application. However, copper cables like cat6/cat6a cable that can support up to 10Gbqs have proven themselves and been widely deployed in the home or office buildings. But for the copper cable, there exists the debate about unshielded twisted pair (UTP) vs. shielded twisted pair (STP). Thus this article aims to provide the detailed information about UTP and STP cables to help users make an informed decision.

Alien Crosstalk (ANEXT)

We all know that copper cable suffer from higher signal loss than fiber optic cable and can be easily interfered by the nearby powers or generator. Alien crossstalk is the performance parameter in copper cables, especially the UTP cables. The following image demonstrates different reactions of the UTP and STP cables to the ANEXT.

So what is the Alien crosstalk? Alien Crosstalk (ANEXT) is a crosstalk that occurs between adjacent cables and connecting hardware. Alien crosstalk in high-speed application is far more severer than in lower-bandwidth infrastructure. It might not be a problem at the lower frequencies of cat 5e and cat 6a cables, but the limiting noise source of the cat 6a systems.

In UTP copper cabling, the alien crosstalk will increase when adjacent cables are close proximity, which is indeed a nightmare to users. Therefore, it is typically recommended to let cat6a cable lay loosely in pathway instead of tight, twisted bundles. People usually have the misconception that if they use STP cables, then alien crosstalk would not be a problem. However, if the shield is not terminated correctly even a shielded system can fall foul of alien crosstalk.

UTP and STP Copper Cable

Twisted pair cables are widely used in transmitting information, especially across great distances. The twist in the wire cancels out any magnetic interference that may develop in the wiring. There are two common types of twisted pair cabling, STP and UTP.

Unshielded Twisted Pair (UTP)

Unshielded twisted pair 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. Unshielded twisted-pair cable does not rely on physical shielding to block interference. It relies instead on balancing and filtering techniques using media filters, baluns or both. Noise is induced equally on two conductors and is canceled out at the receiver.

With properly designed, manufactured and installed UTP cable, the network is easier to maintain than one in an STP cable plant, with its shielding continuity and grounding issues. UTP cables can be found in different categories, for instance, cat 5 UTP for specifications to 100 MHz and cat 6a UTP cables for specifications to 500 MHZ. Best buy Ethernet cable you can afford, most small business would purchase Cat 5e or Cat 6 cables.

Shielded Twisted Pair (STP)

Shielded twisted pair cable contains a hidden metal coating that protects wires from radio and electromagnetic interference. How effective the shielding is depends on the material used for the shield, its thickness and frequency, the type of electromagnetic noise field, the distance from the noise source to the shield, any shield discontinuity and the grounding practices. Also, crosstalk and signal noise can increase if the effects of the shield are not compensated for.

When people install and maintain them properly, STP cables greatly reduce crosstalk. This enhances dependability and boosts data transmission speeds in buildings that contain microwave equipment, HVAC systems or radio transmitters. There are many acronyms used on the market to describe shielded cables, from STP to F/FTP; while many are often used synonymously, nearly all of them have different meanings. This blog provides basic information about each style, as defined by ISO/IEC 11801:200, to clear up the confusion.

F/UTP (FTP)

An overall foil shield (F) with unscreened twisted pairs (UTP). This cable is very much like common UTP cables, with the addition of foil underneath the main cable jacket. Another common name for this cable is FTP. F/UTP cables are common in 10GBaseT applications.

S/UTP

An overall braid screen (S) with unscreened twisted pairs (UTP). This is occasionally referred to as an STP cable, but beware: There are other shielded cables among this list that may also claim this term. To be sure, always check to see whether your cable will have any kind of overall barrier, and whether the individual pairs have their own shield.

SF/UTP

Both an overall braid screen (S) and foil shield (F) with unscreened twisted pairs (UTP). This cable is also occasionally referred to as an STP cable. Cables with an overall braided screen are very effective at protecting EMI from entering or exiting the cable, but heavier, thicker and more difficult to install than its UTP counterpart.

S/FTP

An overall braid screen (S) with foil screened twisted pairs (FTP). The ‘shield’ underneath the jacket is a braid, and each individual pair is surrounded by its own foil barrier. The purpose of the additional foil on individual pairs is to limit the amount of crosstalk between them.

F/FTP

An overall foil shield (F) with foil screened twisted pairs (FTP). Similar to F/UTP cables, these shielded cables are commonly used in 10GBaseT applications.

U/FTP

No overall shielding or braid (U) with foil screened twisted pairs (FTP). This type of shielded cable is commonly used in 10GBaseT applications as well.

To sum up

• STP cables are shielded, while UTP cables are unshielded.


• STP cables are more immune to interference and noise than UTP cables.


• STP cables are better at maximizing bandwidth compared to UTP cables.


• STP cable cost more per meter compared to UTP cables.


• STP cables are heavier per meter compared to UTP cables.


• UTP cables are more prevalent in SOHO networks while STP is used in more high-end applications.

Which One Should I Use?

A key factor in this decision is an analysis of how prevalent EMI will be in the installation environment. EMI is commonly caused by nearby motors, generators, air conditioners, and even office mainstays such as fluorescent lights and printers. EMI can cause crosstalk between circuits, resulting in degradation of data, increased errors and slower transmission rates.

While even UTP cables reduce some EMI, shielded STP cables more effectively block interference. STP cables are ideal for high-speed networks such as data centers where 10GBase-T networks are used because 10G Ethernet is significantly more sensitive to EMI. Shielded cables also come in handy when installers must run wires next to fluorescent lights, microwave ovens or powerful motors.

STP cables are also used in outdoor environments where the cables are exposed to the elements and man-made structures and equipment that may introduce additional interference. It also stops criminals from using jammers to interrupt communications between cameras and indoor monitors or recording equipment.

However, people use UTP cables in the vast majority of homes, offices, and even in large scale businesses due to its lower cost. Unshielded phone and network wiring performs well in most buildings. If you don’t have major concerns about interference, it’s wise to avoid the cost and complexity of STP wiring.

Note that shielded cabling is more expensive than unshielded cabling and more difficult to install; it’s stiffer, making it less flexible. The cable also has a larger diameter, taking up more space in conduit. UTP, on the other hand, actually provides faster transmissions in the absence of EMI. It’s less expensive to purchase, easier to install and has been the standard for many years, so it’s already in place in most existing installations.

Conclusion

It is really doesn’t matter whether you use STP or UTP cables, make sure to install high-quality cabling. High-quality cabling will get you out of the trouble, reducing long-term replacement and labor costs. FS.COM offers a full range of UTP and STP copper cables with great customer feedback. If you are still not sure what type of wiring you need, please visit fs.com.

Oznake: UTP, STP, copper cable, best buy Ethernet cable

Comparison Among Twisted Pair, Co-axial Cable and Fiber Optics

srijeda , 15.06.2016.

In communication systems, massive bundles of wires and cables are used to transport data between servers and other equipment. These cables can be twisted pair cables, co-axial cables and fiber optic cables. Since all these three types can be applied to network communications, it’s essential to determine which cable type is the best for the reliable and efficient data transfer, meaning that a basic understanding of their respective designs and features is necessary. This text aims to compare these three kinds and discuss the differences among them.

Twisted Pair Cable
Twisted pair cable is a kind of wiring in which two conductors of a single circuit are twisted together, with one conductor serving as the forward circuit and the other as the return circuit. The twisted cabling design helps to reduce noise from outside sources and crosstalk on multi-pair cables, making it suitable for use in the field of telecommunication for a long time.

Twisted pair cable comes in two versions (image shown below): unshielded twisted-pair (UTP) and shielded twisted-pair (STP). Since UTP cable lacks shielding, it’s more susceptible to interference from electronic devices. Or in another way, STP cable consists of a foil jacket which helps to prevent crosstalk and noise from outside source. STP is commonly used in Token Ring networks and UTP is in Ethernet networks.

Co-axial Cable
Co-axial cable, or sometimes referred to as coax, is a type of cable that has four layers. That is, at the core is an inner conductor which is surrounded by a foam insulation, symmetrically surrounded by a woven braided metal shield, then covered in a plastic jacket (just as the following picture shows). Because of its insulating property, coaxial cable can carry analogy signals with a wide range of frequencies. It’s seldom used in computer networks anymore, but widely used in cable television services and video connections, like those used by closed circuit surveillance systems.


There are two coaxial cables: 75 Ohm and 50 Ohm. The former is primarily used to transmit a video signal, like television signals over cable. While the main application of the latter is transmission of a data signal in a two-way communication system. Other typical applications include computer Ethernet backbones, wireless antenna feed cables, GPS (Global Positioning Satellite) antenna feed cables and cell phone systems.

Fiber Optic Cable
Fiber optic cable is the complete assembly of fibers, and uses light pulses to transmit information down fiber lines instead of using electronic pulses to transmit information down copper lines. Each of the optical fiber elements is individually coated by plastic layers and contained in a protective tube. A fiber optic cable can accommodate many wavelengths (or channels), able to accommodate ever-increasing data capacity requirements. When terminated with LC/SC/ST/FC/MTRJ/MU/SMA connectors on both ends, such as LC-LC, LC-ST, SC-SC, ST-ST, LC SC cable, fiber optic cables can achieve fiber link connection between equipment during fiber cabling.


Comparison Among Three Cables
Before delving into comparison between these three cables, a table about their respective strengths and weaknesses is available.


Comparing Twisted Pair & Co-axial Cable
Both twisted pair and co-axial cable can support network speeds in both the megabit and gigabit ranges. Both are susceptible in varying degrees to signal interference, as well as signal leakage. (Signal interference occurs when external signals interfere with transmission inside the cable, and signal leakage means that signals inside the cable leak out and become a source of interference to other devices.) Coaxial cable, being of a standard design, varies little in its susceptibility to interference. For twisted pair cable, however, the cable’s resistance to interference depends in large part on the degree to which the twisting scheme remains in place, and therefore can vary widely.

Comparing Twisted Pair & Fiber Optic Cable
Judging from cable and installation costs to tooling and transceivers, twisted pair, here mainly refers to UTP, is much less costly than fiber optic cable. The one obvious difference lies in the quality. Passive to active UTP systems offer performance similar to fiber, providing noise immunity, attenuation compensation, surge protection and ground loop isolation. Because of this point, those users, who once deployed fiber optic cables for runs beyond the range of co-axial cable, now choose UTP for transmission. Fiber optic cable is good for extremely long runs (over one mile) or for safety when video is run in the same conduit with high voltage.

Allowing for distance, if cable runs less than 250 feet, co-axial cable is probably the best option. Between 250 and 8,000 feet, UTP wire is often the best one. If the runs are more than 8,000 feet, it’s advised to select fiber optic cable.

Conclusion
While deciding whether to use co-axial cable, twisted-pair, or fiber optic cable for transmission, it’s imperative to collect the basic information about them, and take the cost, cable runs and other external conditions into consideration. In Fiberstore, you can find different types of UTP cable (eg. Cat 5, Cat5e, Cat6) and various fiber optic cables (say LC SC cable mentioned above, SC to SC fiber patch cable). You can go to Fiberstore to know more information about both copper and fiber optic cables.

Oznake: twisted pair, co-axial cables, UTP, STP, fiber optic cables, LC SC cable, SC to SC fiber patch cable