Tag Archive | fiber jumper

How to Configure RJ45 Pinout

Ethernet cable, as one of the most popular types of networking cable, is mainly utilized to interconnect two wired network devices in the home or the office. Cat 5/cat6, UTP/STP cables are some of this cable type that connects all devices to get a network up and running smoothly. Unlike the fiber jumper, this Ethernet copper cable is usually terminated with a 8P8C modular connector, which is often called RJ45 (Registered Jack). The way the RJ45 connector wired to Cat 5, 5e and 6 cables differs depending upon the type of cable required.

It is known to all that, inside the Ethernet cable, there are eight color coded wires twisted into 4 pairs of wires, which poses difficulty in effectively wiring them. So how to terminated RJ45 connectors at the end of the network cable? In fact, there are three wiring standards available on the market—straight-through cables, crossover cables and rollover cables. In order to have a better understanding of the RJ45 pinout, this article will provide some basic information about them.

Different Wiring Standards

Before starting with the discussion of cable pinout for modular jack, we often get questions as to the difference in straight-through, crossover, and rollover wiring of cables and the intended use for each type of cable. These terms describe the way the cables are wired (which pin on one end is connected to which pin on the other end). The following part shows the exact pinout schemes of the three cables.

  • Straight-Through Cables

For this type of cable, the wiring of both ends is the same, in other words Pin 1 connector A goes to Pin 1 on connector B, Pin 2 to Pin 2 etc. Straight-through wired cables are most commonly used to connect a host to client. When we talk about cat 5e patch cables, the straight-through wired cat5e patch cable is used to connect computers, printers and other network client devices to the router switch or hub. Straight-through cable can be either terminated with T568A or T568B standard, just as you can see in the below image.


  • Crossover Cables

Crossover cables are very much like Straight-Through cables with the exception that TX and RX lines are crossed (they are at opposite positions on either end of the cable), that’s it, Pin 1 on connector A goes to Pin 3 on connector B. Pin 2 on connector A goes to Pin 6 on connector B, etc. Crossover cable are usually terminated with one end with T568A and the other end with T568B standard This means that two similar devices can communicate with each other, so this is how to connect two computers or two switches or hubs to each other. Crossover cables are most commonly used to connect two hosts directly. Examples would be connecting a computer directly to another computer, connecting a switch directly to another switch, or connecting a router to a router.

  • Rollover Cables

A rollover cable as the names implies, refers to the one where the pinouts are reversed. Pin 1 becomes pin 8 and pin 2 becomes pin 7. This type of cable is not used in computer networks, except in very special applications. Rollover cables, sometimes referred to as host cables are most commonly used to connect to a devices console port to make programming changes to the device. Unlike crossover and straight-wired cables, rollover cables are not intended to carry data but instead create an interface with the device.

Cabling Standards—T568A and T568B

Ethernet cables are twisted into 4 wires coded with different colors. The four colors used on Cat 5 and 6 cables are green, orange, blue and brown. One wire in each pair has a solid color and the other has a white stripe added. The telecommunication industry has two standards for cable RJ45 pinouts: T568A and T568B. These standards determine how each of the four pairs of colored wires is connected on the RJ45 connector.


When visually comparing the T568A and T568B wiring configurations side-by-side, you will see that that the pin positions for the green and orange pairs are swapped. On T586A cables, pin 1 is white-green and pin 2 green, whereas on T586B cables, pin 1 is white-orange and pin 2 orange. The difference continues in that pins 3 and 6 are used for the other color. With both standards, the blue pair is always on pins 4 and 5 and the brown pair on pins 7 and 8. T586B is the most common, although the government often uses T586A. The choice is irrelevant provided all components follow the same standard.

How to Configure Ethernet Cable for T568A or T568B

T568A and T568B standards were recognized by ANSI, TIA and EIA. The first is the T568A wiring standard and the second is T568B. Nowadays T568B has surpassed 568A and is seen as the default wiring scheme for twisted pair structured cabling. But this cannot be the unique standard to determine which one is suitable than the other. In fact, whether to choose one standard over the other really depends upon the configuration of the existing network you are working on or if you are building a network from the ground up. The benefit to using the more popular T568B wiring scheme is that it is backward compatible to USOC wiring schemes, but it also accommodates current and future demands on the network.

If you are working on an existing network, it is important to continue with the existing wiring scheme for straight through cables. If this is unknown, this can be determined by testing the cables for continuity. Mixing the two schemes will prevent data signals from transferring simply because the individual colored and striped wires will not be matching up when you connect the plugs and jacks. Or in some circumstance, it may be necessary to mix the two configurations when previously T568A-wired components will be connected to T568B components. In this case, you would want to create a crossover cable by terminating one end with a T568A terminated plug and the other with a T568B plug to prevent data loss.


The RJ45 pinout standards specify two wiring schemes on how to configure RJ45 Ethernet cable. While the T568A and T568B wiring standards are very similar, the T568B scheme is more commonly used for many data cable applications. Note that whether to use T568A or T568B really depends on the existing wiring, jacks or personal preference, and you should take consistency into account as well. FS.COM provides a full range of optical devices, including the Ethernet cables, fiber optic cables, optical transceivers, DAC/AOC and so on. Custom fiber patch cords are also offered. All of our products are well-tested before shipping, if you want to know more, please send your request to us.

Difference Between Twisted Pair Cable and Coaxial Cable

A wire or cable is an indispensable element in communication system for connecting optical devices like optical transceivers, router and switch. Recently the most common cable types deployed in communication system are fiber optic cable, twisted pair cable and coaxial cable. Both twisted pair cable and coaxial cable are copper cables, so what’s the difference between them? This article may help you sort it out.

Twisted Pair

Twisted pair cables as the names implies, consists of a pair of cables twisted together, which has been utilized in telecommunication field for a long time. The twisting can avoid noise from outside sources and crosstalk on multi-pair cables, so this cable is best suited for carrying signals. Basically, twisted pair cable can be divided into two types: unshielded twisted-pair (UTP) and shielded twisted-pair (STP).


UTP is for UNshielded, twisted pair, while STP is for shielded, twisted pair. UTP is what’s typically installed by phone companies and data communication (though this is often not of high enough quality for high-speed network use) and is what 10BaseT Ethernet runs over. However, STP distinguishes itself from UTP in that it consists of a foil jacket which helps to prevent crosstalk and noise from outside source. It is typically used to eliminate inductive and capacitive coupling, so it can be applied between equipment, racks and buildings.

Coaxial Cables

Coaxial cable is composed of an inner solid conductor surrounded by a paralleled outer foil conductor that is protected by an insulating layer. A coaxial cable has over 80 times the transmission capability of the twisted-pair. Coaxial cable has also been the mainstay of high speed communication and has also been applied to network with 10 Gigabit links data centers, because it is proved to be cost efficient for short links within 10 m and for residential network.

coax cable

Comparison Between Twisted Cable and Coaxial Cable

Most people now are quite familiar with what coaxial cables are, as they are used in almost every home for cable television connections. These data cables are also popular in local area networks (LAN) because they are highly resistant to signal interference, which also gives coax cables the ability to support longer cable lengths between two devices.

The biggest advantage of twisted cables is in installation, as it is often thinner than coaxial cables and two conductors are twisted together. However, because they are thinner, they can not support very long runs. These tightly twisted designs cost less than coaxial cables and provide high data transmission rates. They connect with the RJ45 connector, which looks similar to a telephone jack but is designed for twisted pair pins.

In the end, twisted pair cabling is better suited when cost and installation are an issue and if EMI and crosstalk are not too much of a problem. But for coaxial cable, it supports greater cable lengths, and can be shielded in a variety of ways—with a foil shield on each conductor, a foil or braid inside the jacket or a combination of individual conductor and jacket shielding.

Additional Information About Fiber Optic Cables

Besides Twisted and coaxial cables, here comes a new generation of transmission media—fiber jumper. Fiber optic cables have a much greater bandwidth than metal cables, which means they can carry more data. They are also less susceptible to interference. For these two reasons, fiber optic cables are increasingly being used instead of traditional copper cables despite that they are expensive. Nowadays, two types of fiber optic cables are widely adopted in the field of data transfer—single mode fiber optic cables and multimode fiber optic cables.

LC-SC fiber patch cable

Single mode optical fiber is generally adapted to high speed, long-distance applications. While a multimode optical fiber is designed to carry multiple light rays, or modes at the same time, which is mostly used for communication over short distances. Optical fiber cables are also available in various optical connectors, such as LC to SC patch cord, LC to ST fiber cable, SC FC patch cord, etc. The picture above shows a LC to SC patch cord.


Some engineers confirm that fiber optic cables is sure to be the dominant transmission media in telecommunication field, while others hold that copper cables will not be out of the stage. Thus, whether to choose fiber optic cables, twisted cables or coaxial cables, it is advisable for you to have a full understanding of your application before selecting these data cables. All types of Ethernet cables as well as fiber optic cables are provided at FS.COM. Our Quick Order Tool will help you find what you need. If you have any requirement of our products, please send your request to us.

What Will Affect the Longevity of Your Fiber Network?

When deploying a fiber network, people nowadays not only appreciate the high-speed broadband services, but the maintenance of how long it will last. After all, optical fiber is a particular type of hair-thin glass with a typical tensile strength that is less than half that of copper. Even though the fiber looks fragile and brittle, but if correctly processed, tested and used, it has proven to be immensely durable. With this in mind, there are essentially factors that will affect the longevity of your fiber network.

fiber network

Installation Strains

Stress, on the other hand, is a major enemy of fiber longevity, so the protection task is passed to the cable installer, who will ensure that the use of suitable strength elements limits the stress applied to the cable to much less than the 1 per cent proof test level. The installer then needs to ensure that the deployment process does not overstrain the cable. Figure 2 below illustrates a typical crew deployment for a trunk installation. The whole process should be paid more attention to the stress.

Figure 2 below illustrates a typical crew deployment for a trunk installation

Of the three techniques commonly used—pulling, pushing and blowing, only pulling creates undesirable stretching (tensile stress). Unlike metal, glass does not suffer fatigue by being compressed, and so the mild compression caused during pushing causes no harm to the fiber.

Surface Flaws

Optical fiber typically consists of a silica-based core and cladding surrounded by one or two layers of polymeric material (see in Figure 3). Pristine silica glass that is free of defects is immensely resistant to degradation. However, all commercially produced optical fibers have surface flaws (small micro-cracks) that reduce the material’s longevity under certain conditions. The distribution of flaws on the surface of the silica-based portion of the fiber largely controls the mechanical strength of the fiber. FS.COM fiber optic cables are well tested to ensure less surface flaws, like LC to ST fiber cable.

standard opticla fiber

To conquer this, reputable fiber suppliers carry out proof testing, which stretches the fiber to a pre-set level (normally 1 per cent) for a specified duration to deliberately break the larger flaws. And the user is then left with a fiber containing fewer, smaller flaws that need to be protected from unnecessary degradation. This means primarily stopping the creation of new flaws by coating the fiber with a protective and durable material for its primary coating.

Environmental Factors

Once deployed, the local environment has a big impact on fiber life. Elevated temperatures can accelerate crack growth, but it is the presence of water that has been historically of most concern. The growth of cracks under stress is facilitated by water leading to “stress corrosion”. You can check what the tendency of a fiber to suffer stress corrosion is by reviewing its “stress corrosion susceptibility parameter”, much more conveniently referred to as “n”. A high n value (around 20) suggests a durable fiber and coating.

Calculating How Long Your Network Will Last

Bearing in mind the three factors above, how can you calculate the lifetime of your fiber network? In general, the chances of a fiber being damaged by manual intervention, such as digging, over the same time frame is about 1 in 1,000. Quality fiber, installed by benign techniques and by careful installers in acceptable conditions should, therefore, be extremely reliable – provided it is not disturbed.

It is also worth pointing out that cable lengths themselves have rarely failed intrinsically, but there have been failures at joints where the cable and joint type are not well matched, allowing the fibers to move – for example, due to temperature changes. This leads to over stress of the fiber and eventual fracture.


To tell the truth, the biggest enemies to the carefully engineered reliability of fiber jumper can be either humans or animals, rather than the fused silica itself. The provided fibers are stored and coiled correctly, it is quite possible that they turn out to be stronger than we at first thought and perhaps the original flaws begin to heal with time and exposure to water under low stress levels. FS.COM offers high quality fiber cable assemblies such as Patch Cords, Pigtails, MCPs, Breakout Cables etc. All of our products are well tested before shipment. If you are interested, you can have a look at it.

How to Reduce the Cost of FTTH Architecture

In our digital world, people increasingly require higher bandwidth to facilitate daily life, whether for leisure, work, education or keeping in contact with friends and family. The presence and speed of internet are regarded as the key factor that subscribers would take into account when buying a new house. Recently there are a growing number of independent companies offering full fiber to the home (FTTH) services, ranging from local cooperatives and community groups to new operators. Today’s article will pay special attention to the reasons why we should implement FTTH network and the methods to reduce the cost of FTTH network.

Why Should We Deploy FTTH Network?

FTTH logo

No denying that the world is changing rapidly and becoming increasingly digital. People nowadays are knowledgeable workers who rely on fast connections to information stored in the cloud to do their jobs. Therefore, installing superfast FTTH broadband is an investment in equipping communities with the infrastructure they need to not just adapt to the present life, but to thrive in the future.

What’s more, the economic benefits of FTTH, for residents, businesses and the wider community are potentially enormous. While there are upfront costs in FTTH deployments, particularly around the last drop, equipment and methodologies are evolving to reduce these significantly. Fiber to the home is proven to increase customer satisfaction, and enables operators to offer new services, such as video on demand, 4K TV and smart home connectivity.

As well as bringing in economic benefits, FTTH broadband provides local businesses with the ability to expand, invest and seek new opportunities by providing rapid connections to major markets. All of this leads to increased investment in the rural economy, providing residents with more choice and stimulating growth.

What to Do?

Although deploying FTTH network might be similar cost as deploying copper network, there are some methods that you should know about reducing the costs of FTTH architecture. Adopting the following three principles helps achieve FTTH deployment, maximizing return on investment and dramatically reducing deployment times.

1. Reuse the Existing Equipment

Time and the total cost of FTTH deployment are typically relevant with the civil engineering side of the project, such as digging a new trench and burying a new duct within it. Where possible, crews should look to reuse existing infrastructure—often there are ducts or routes already in place that can be used for FTTH and in building deployments. These could be carrying other telecommunication cables, power lines, or gas/water/sewerage. Installing within these routes requires careful planning and use of cables and ducts that are small enough to fit through potentially crowded pathways. Figure 2 shows a generic point-multipoint architecture that fiber jumper plays an important part in it.

FTTH architecture

Additionally utilizing the push and pull cables in FTTH infrastructure simply reduce costs and install time as network installers can easily complete FTTH deployment by using pushing or pulling cables: pushing can be aided by simple, cost-effective handheld blowing machines, or pulled through the duct using a pre-attached pull cord. Even for more complex and longer environment, FTTH deployment can be quickly completed other than requiring expensive blowing equipment to propel the cable through duct.

2. Choose the Right Construction Techniques

If it is time to start digging, always make sure you use appropriate construction methods. The appropriate method will minimize cost and time by making construction work as fast and concentrated as possible, avoiding major disruption to customers or the local area. And remember to make sure you follow best practice and use the right fiber cable and duct that can fit into tight spaces and withstand the high temperatures of the sealant used to make roadways good.

FTTH deployment

The cable and duct used within FTTH implementations is crucial. Ensure that it meets the specific needs of deployments, and is tough, reliable and has a bend radius. It should be lightweight to aid installation and small enough to fit into small gaps and spaces in ducts. Also look to speed up installations with pre-connectorized cables that avoid the need to field fit or splice.

3. Minimize the Skills Required

Staff costs are one of the biggest elements of the implementation budget. Additionally, there are shortages of many fiber skills, such as splicing, which can delay the rate at which rollouts are completed. Operators, therefore, need to look at deskilling installations where possible, while increasing productivity and ensuring reliability. Using pre-connectorized fiber is central to this—it doesn’t require splicing and is proven to reduce the skill levels needed within implementations.


To cope with the digital world, the network is in constant need of enhancements and the increasingly stressed bandwidth and performance requires ongoing adjustment. Regardless of the FTTH architecture and the technology to the curb, the pressure is on for the network installer to deploy FTTH quickly and cost-effectively, while still ensuring a high quality, reliable installation that causes minimal disruption to customers and the local area. Fiberstore offers a variety of optical equipment that are suitable in telecom field. Our fiber optic cables are available in different optical connector, single-mode and multimode fiber as well as indoor or outdoor cables. For example, patch cord LC-LC are also provided.