A Guidance to Fiber Optic Cable Selection

With the advances of the information age, a great amount of people specialized in the field of network communication begins to attach great importance to the selection of fiber optic cables. From data and voice to security and videoconferencing, plenty of contemporary cable infrastructure services depend heavily on fiber optics to transmit information of farther distance at a higher speed, which makes fiber optics a standard component in daily communication nowadays. Fiber optics are considered to be a desirable cable medium because of its immunity to electromagnetic interference (EMI) and radio frequency interference (RFI) , not to mention its bandwidth that helps to meet the increased capacity demand, and its reliable reputation to ensure worry-free maintenance. This article is going to focus primarily on some essential component in fiber optic installation and provide some insight into selecting the right fiber optic cable.

The Necessities of Selecting the Right Type of Fiber

Fiber optic cable basically can be used in a wide variety of applications, ranging from small office LANs, data centers to inter-continental communication links. Moreover, its ability to transport signals for significant distances also contributes to its popularity in most networks, whether they are local, wide area or metropolitan. In fact, fiber optic cable is now running down many residential streets and brought directly to the house. Thus, choosing the appropriate fiber optic cable is extremely important for any installation.

It is known to all that the selection concerning the right type of fiber should be based on the immediate application since it varies in different circumstances. Besides, installers should also consider upcoming applications and capacity needs. Future bandwidth demands, transmission distances, applications, and network architecture influence fiber selection just as much as current needs. Therefore, a careful assessment of potential network usage will help avoid the costs of preventable upgrades.

Single-mode Fiber Optic Cable vs. Multimode Fiber Optic Cable

First and foremost, on selecting the right type of fiber, one should decide the mode of fiber needed. The mode of a fiber cable describes how light beams travel on the inside of the fiber cables themselves. Since the two modes aren’t compatible with each other and you can’t substitute one for the other, it is important to make the right choice.

Single-mode fiber optic cable uses a single strand of glass fiber for a single ray of light transmission, which can accommodate further distances and offer virtually unlimited bandwidth. Single-mode has the capacity to carry a signal for miles, making it an ideal option for telephone and cable television providers. And it is also usually employed in campus and metropolitan networks. Single-mode fiber requires laser technology for sending and receiving data, and the high-powered lasers transmit data at greater distances than the light used with multimode fiber.

Multimode fiber optic fiber, as the name indicates, allows the signal to travel in multiple modes, or pathways, along the inside of the glass strand or core. Multimode fiber optic cable is generally adopted in applications involving shorter distances like data center connections. Multimode fiber optic cable transmits Gigabit Ethernet up to 550 m, although it can’t compete with single-mode fiber optic cable in terms of transmission distance, multimode fiber cable is still proved to be a cost-efficient and economical solution.

Making the Connection

Connections play an essential role in keeping the information flowing from cable to cable or cable to device. There are lots of connector styles on the market including LC, FC, MT-RJ, ST and SC. There are also MPO/MTP style connectors that will accommodate up to 12 strands of fiber and take up far less space than other connectors. Among them, manufacturers and distributors are more likely to have equipment to accommodate ST and SC style connectors than any other connector style. Especially the SC connectors, with better performance against loss, more efficient installation and easier maintenance, has earned its place in today’s networking applications. As for those data center managers who attach more importance to space-saving, the LC connector is a more ideal option. These connectors offer even lower loss in a smaller form factor and provide higher performance and greater fiber density.

Evaluating Interface Options

In addition to fiber type and connector selection, another vital issue for the technician is to evaluate the interface option which determines the network performance. The selection of interface is relevant to the fiber type, cable distance and speed of the connection as well. Installers can rely on modular Gigabit fiber-optic interfaces, called gigabit interface converters (GBICs) for most interface converters. These flexible interfaces come in several form factors, including XENPAK and SFP+, and can accommodate a variety of device applications. The picture below shows a typical gigabit fiber optic converter.

Gigabit fiber optic converter

While choosing the right interfaces, installers need to take their light sources into consideration. Light-emitting diodes (LEDs) work only with multimode fiber and operate at the 850nm window; laser works only with single-mode fiber and operates at the 1550nm window; and vertical-cavity surface-emitting laser (VCSEL) works with both types of fiber and operates at the 1310nm window.

Conclusion

In summary, to build a well-performed fiber optic system, realizing the applications and capacity expectations should be put into first place. As you can see, selecting the appropriate cable design for your application should require a thorough review of the entire pathway for the cable, including the type of fiber, optical connectors as well as interface options. The decision of selection can affect the fiber protection and performance, ease of the installation, splicing or termination, service lifetime, and, most importantly, cost.

 

Guide To Choose The Best Fiber Optic Cable Suits Your Application

Fiber optic cable is favored for today’s high-speed data communications because it eliminates the problems of twisted-pair cable, such as near-end crosstalk (NEXT), electromagnetic interference (EMI), and security breaches. Fibre Optic Cable is the preferred option in the interconnecting links between floors or buildings, is the backbone of any structured cabling solution. While, making the right decisions when it comes to Data Network cabling is difficult as it can make a huge difference in the ability of your network to reliably support current and future requirements. There are many factors to consider and today I will guide you through the many options available and find the best one suits your application.

1. Multimode Fiber Cable Or Single-mode Fiber Cable

There are two basic types of fiber: mulitimode and single-mode. Both types consist of two basic components: the core and the cladding which traps the light in the core.

Multimode fiber cable

Multimode fiber, as the name suggests, permits the signal to travel in multiple modes, or pathways, along the inside of the glass strand or core. It is available with fiber core diameters of 62.5 and a slightly smaller 50 microns. The problem with multimode fiber optics is that long cable runs in multiple paths may lead to signal distortion. This can result in incomplete and unclear data transmission.

Applications covering short distances can use multimode fiber optic network cable. Ideal uses for such kinds of cables are within data center connections. Multimode cables are economical choices for such applications. There are various performance levels within the multimode fiber optic cable such as OM3 cable for distances within 300 m, OM4 cable supports Gigabit Ethernet distances within 550m and 10G applications.

Single-mode fiber cable

Single-mode fiber cables offer a higher transmission rate. These cables contain a tiny core that measures about five to ten microns. These tiny cores have the capacity to eliminate distortion and produce the highest transmission speeds. Single-mode fiber generally has a core that is 8.3 microns in diameter. Singlemode fiber requires laser technology for sending and receiving data. Although a laser is used, light in a single-mode fiber also refracts off the fiber cladding. The presence of high intensity lasers helps transfer data across large distances. Singlemode has the ability to carry a signal for miles.

Single mode is used for long haul or extreme bandwidth applications, gives you a higher transmission rate and up to 50 times more distance than multimode, but it also costs more. The small core and its single lightwave virtually eliminate any distortion that could result from overlapping light pulses, providing the least signal attenuation and highest transmission speeds of any fiber cable type.

The best choice to choose multimode optical cable when the transmission distance is less than 2km. In the other sides, use single-mode optical cable when the transmission is more than 2km. Although the core sizes of multimode and singlemode fiber differ, after the cladding and another layer for durability are applied, both fiber types end up with an outer diameter of about 250 microns. This makes it both more robust and easier to work with.

2. Indoor Cable Or Outdoor Cable

The major difference between indoor and outdoor cables is water blocking. Any conduit is someday likely to get moisture in it. Outdoor cables are designed to protect the fibers from years of exposure to moisture.

Indoor Cables

Indoor cables are what we call “tight-buffered” cables, where the glass fiber has a primary coating and secondary buffer coatings that enlarge each fiber to 900 microns—about 1mm or 1/25-inch—to make the fiber easier to work with. Indoor cables are flexible, and tough, containing multiple Tight Buffered or Unit Cord fibers.

Types Of Indoor cables available

indoor cables

Simplex and Zip Cord: Simplex Fiber Optic Cables are one fiber, tight-buffered (coated with a 900 micron buffer over the primary buffer coating) with Kevlar (aramid fiber) strength members and jacketed for indoor use. The jacket is usually 3mm (1/8 in.) diameter. Zipcord is simply two of these joined with a thin web. It’s used mostly for patch cord and backplane applications, but zipcord can also be used for desktop connections. They are commonly used in patch cord and backplane applications. Additionally, they can be utilized for desktop connections. These cables only have one fiber and are generally used indoors.

Distribution cables: They contain several tight-buffered fibers bundled under the same jacket with Kevlar strength members and sometimes fiberglass rod reinforcement to stiffen the cable and prevent kinking. These cables are small in size, and used for short, dry conduit runs, riser and plenum applications. The fibers are double buffered and can be directly terminated, but because their fibers are not individually reinforced, these cables need to be broken out with a “breakout box” or terminated inside a patch panel or junction box. The distribution cable is smaller and used in dry and short conduit runs, plenum and riser applications, is the most popular cable for indoor use.

Breakout cables: They are made of several simplex cables bundled together inside a common jacket for convenience in pulling and ruggedness. This is a strong, rugged design, but is larger and more expensive than the distribution cables. It is suitable for conduit runs, riser and plenum applications, is ideal for industrial applications where ruggedness is important or in a location where only one or two pieces of equipment (such as local hubs) need to be connected.

Outdoor Cables

Optical fiber in outdoor applications requires more protection from water ingress, vermin, and other conditions encountered underground. Outdoor cables also need increased strength for greater pulling distances. Buyers should know the potential hazards that the cables will face, for example, if the cables will be exposed to chemicals or extreme temperatures.

Loose Tube cables: These cables are composed of several fibers together inside a small plastic tube, which are in turn wound around a central strength member and jacketed, providing a small, high fiber count cable. This type of cable is ideal for outside plant trunking applications, as it can be made with loose tubes filled with gel or water absorbent powder to prevent harm to the fibers from water. Since the fibers have only a thin buffer coating, they must be carefully handled and protected to prevent damage. It can be used in conduits, strung overhead or buried directly into the ground.

Ribbon Cable: This cable offers the highest packing density, since all the fibers are laid out in rows, typically of 12 fibers, and laid on top of each other. This way 144 fibers only has a cross section of about 1/4 inch or 6mm! Some cable designs use a “slotted core” with up to 6 of these 144 fiber ribbon assemblies for 864 fibers in one cable! Since it’s outside plant cable, it’s gel-filled for water blocking.

Armored Cable: Cable installed by direct burial in areas where rodents are a problem usually have metal armored between two jackets to prevent rodent penetration. This means the cable is conductive, so it must be grounded properly. You’d better choose armored fiber cable when use cable directly buried outdoor.

Aerial Cable: They can be lashed to a messenger or another cable (common in CATV) or have metal or aramid strength members to make them self supporting. Aerial cables are for outside installation on poles.

The table below summarizes the choices, applications and advantages of each.

Cable Type Application Advantages
Distribution Premises Small size for lots of fibers, inexpensive
Breakout Premises Rugged, easy to terminate, no hardware needed
Loose Tube Outside Plant Rugged, gel or dry water-blocking
Armored Outside Plant Prevents rodent damage
Ribbon Outside Plant Highest fiber count for small size

All cables share some common characteristics. For example, they all include various plastic coatings to protect the fiber, from the buffer coating on the fiber itself to the outside jacket. All also include some strength members for pulling the cable without harming the fibers. Outdoor fiber optic cable has moisture protection, either a gel filling or a dry powder or tape. Direct-buried cables may have a layer of metal armor to prevent damage from rodents. It is advisable that you should customize your cable to make it suitable to your application when the quantity of fiber optic cables is large and also for the cost-effective reasons. Knowing basic information about fiber optic cables make choosing the right one for the project a lot easier. It is always beneficial to konw more about fiber optic cables.

The Benefits of Using Multimode Fiber Optic Cable

The fiber optics technology has been one of the world’s most effective innovation of wire communication occurred. This technology has changed the world, and make the internet behavior today as a practical platform for worldwide access to data and information. And it is not only the internet, but also other kinds of communications that has undergone a sea change owing to the deployment of networks driven by the optical fiber backbone. When it comes to local communication, the multimode fiber optic cable only play a significant role in ensuring high data transmission rates at a high speed and low attenuation within the network with multi-user support.

There are many significant advantages, people will use these cables. Below is a list of the main benefits.

Multi-user framework

The biggest feature is the ability of multimode optical fiber carrying multiple signals at the same time in the same line. Therefore, the network user can send more than one packet in the cable at the same time, and all information will remain unchanged after will reach their destination. Channel will not mix or distort the multiple information channels.

High power signal transmission capacity

Multimode cables are excellent when it comes to carrying a high amount of total power inside the signals. The power is almost keep not loss, and the information is easy to be delivered at the other end of line with out any intermediate magnification.

Real-time data transmission

In the network data transmission in the design of the optical fiber data transmission speed. The high speed of optical transmission network is derived from the fact that the data rather than other more traditional electromagnetic signal. So the soft real-time system is feasible to use the network in some given scenario.

High bandwidth and transfer rate

The multi-channel factor attributes to a high bandwidth and high rate of data transfer.

High security

The optical signal is using total internal reflection – a physical properties or light is reflecting surface. Therefore, it is extremely difficult into the fiber optic network. Therefore, multimode fiber optic cable to enjoy a high level of data security.

Support of multiple protocols

These networks can support many data transfer protocol, including Ethernet, ATM and Infiniband, Internet protocols. Therefore, one can use the cable as the back bone of a series of high value 
applications.

Obviously, a multimode fiber optic cable can be used as a backbone for the cable communication needs with high performance. Use these cables will improve your experience, if you’re using equipment, depending on the level of network performance.

Using multimode fiber cable instead of inferior cable can greatly improve the bandwidth and noise suppression. When choosing fiber optic network cable must have the correct information in determing the solution.

Source: fiberstore.com

What is The Optical Fiber Cable

The fiber optic cable is mainly constituted by the optical fiber (fiberglass) as thin as a hair and plastic protective casing and plastic sheath, and metals such as gold, silver, copper and aluminum in the fiber optic cable, usually no recycling value. The fiber optic cable is a certain number of optical fiber in accordance with certain the cable core outsourcing jacket, and some coated outer sheath for optical signal transmission of a communication line.

fiber optic cable

Communication optical cable with greater transmission capacity than copper cable relay distance, small size, light weight, no electromagnetic interference, since 1976 has developed into a long-distance lines, the city relay, offshore and transoceanic submarine communications , as well as local area networks, private networks, such as cable transmission line backbone, and began to the development of the field of town subscriber loop wiring network, fiber to the home, the wide-generation integrated Services Digital Network transmission line.

The history of fiber optic cable

In 1976, American Bell Institute built the first fiber optic communication experimental system in Atlanta, the use of a cable containing 144 fibers manufactured by the Western Electric Company. In 1980, a commercial made by multimode fiber optic cable using the city interoffice trunks and a few long-distance line. The commercial made of single-mode fiber optic cable in 1983, began to be used in the long-distance line. 1988, the first connection between the United States and Britain and France across the Atlantic submarine cable laying, soon after the completion of the first undersea fiber optic cable across the Pacific. China in 1978, self-developed communications cable, multimode fiber cable core structure of the layer stranded. In Shanghai, Beijing, Wuhan and other places has conducted field trials. In the local telephone network as soon after the interoffice trunks trial, after 1984, gradually for long-distance lines, and began using single-mode fiber.

The cable network is the cornerstone of the information highway

The fiber optic cable network transmission of all kinds of information in today’s information society tools. If the “Internet” is referred to as the “information highway” — fiber optic network, fiber optic network is the cornerstone of the information highway is the physical routing of the Internet. Once a cable is damaged and blocking, the direction of the “information superhighway” shall be destroyed. Outside information through fiber optic cable transmission, in addition to the usual telephone, telex, fax, and now a large number of transmission, there is a TV signal, bank transfer, the moment the stock market can not be interrupted. At present, the transmission mode of long-distance communications cable from PDH to SDH development, the transfer rate from the development of the original 140MB/S to 2.5GB/S, 4 x 2.5GB / S, 16 x 2.5GB / S or even higher, that is,said one pair of the core can be opened for 30,000, 120,000, 480,000, and even to the development of more telephone channels. Such a large transmission capacity, fiber optic cable, once blocking not only to the telecommunications sector, causing huge losses, and communication poor, give to the masses to cause a lot of inconvenience, such as computer users can not access the stock market can not be known, the bank exchange rate can not be, remote memory taken to vanish into thin air, and all kinds of information can not be transferred. In remote mountainous areas, once the fiber optic cable is interrupted, it will make the county even fiber optic cable along several counties in the communication on the isolation and become the islands. The loss caused to the party, government and military authorities and the people is immeasurable.

Fiber or simplified for the optical fiber, is a use of the principle of total reflection of the light in the glass or plastic fibers reach ligh conducting tool. Fine optical fiber encapsulated in a plastic sheath, such that it can be bent and thus will not fracture. Typically, the end of the fiber-emitting devices using ligh emitting diodes (light emitting diode, LED) or a laser light pulse is transmitted to the optical fiber, the other end of the optical fiber of the receiving apparatus using the photosensitive member detection pulse. In daily life, since the conduction losses of light in the optical fiber conduction loss in the wire is much lower than the electrical, optical fibers are used for long distance transmission of information. Gradually lowered with the price of the fiber, the fiber is also used for medical and recreational purposes.

Aticle Source: http://www.fs.com/tutorial.html