Has Wireless Router Killed Ethernet Cable in Home Network?

As home networks have increased in popularity, so has the wireless router. The lack of clutter and the convenience of being able to connect to the Internet almost anywhere means WiFi is the first choice for anyone who is looking to go online. The blistering connection speeds offered by today’s WiFi standards do cause the downfall of wired Ethernet cable and make it appear a bit of a relic, but has wireless router really killed Ethernet cable in home network yet? Read the following text, and you can get the detailed information.

What Is Wireless Router?

Wireless router as shown below is an electronic device that works as a router, meaning it sends data from the Internet cable to a device, and as a wireless access point, so this data can be shared through radio signals instead of another cable. It can function in a wired local area network (LAN), in a wireles-only LAN, or in a mixed wired/wireless network, depending on the manufacturer and model.

What Is Ethernet Cable?

An Ethernet cable is one of the most popular forms of network cable used on wired home networks to connect devices on local area network (LAN), such as PCs, routers, and switches. Ethernet cable is physically manufacturer in two basic forms called solid and stranded. Solid Ethernet cable offers slightly better performance plus improved protection against electrical interference, which is more commonly used on business networks, wiring inside office walls or under lab floors to fixed locations, while stranded Ethernet cable is less prone to physical cracks and breaks making them more suitable for home networking. Cat5, Cat5e and Cat6 with rj45 plug are commonly used Ethernet cable types in home network. The following image shows different color-coded Ethernet cables.

Wireless Router VS. Ethernet Cable

Transmission Speed

When wireless router first moved into the mainstream, it was mostly based on the 802.11g standard, which offers maximum theoretical speeds of 54Mbps, and far less in practice. Thanks to new standards, like 802.11ac and 802.11n, which offer maximum speeds of 866.7Mbps and 150Mbps, respectively, but this still falls well short of the performance offered by Ethernet cable, which can produce speeds anywhere from 100Mbps to 1G and even 10G, depending on different Ethernet cable types. For example, a Cat6 cable can support the transmission distance up to 100 meters at the data rate of 1G, and when crosstalk is in an ideal solution, it can support 55 meters at the data rate of 10Gbps.

Latency

Connection quality just isn’t about raw bandwidth. Latency is also a big factor. Low latency becomes so important since the adoption of private cloud applications increases. It’s beneficial for ensuring fast responses time and reducing CPU (center processing units) idle cycles so that improves efficiency. This is also known as “ping” in online game circles. If you’re playing online games and need reaction time to be as quick as possible, you’re probably better off with a wired Ethernet cable, since it offers the advantage of much lower latency.

Security

Security is another big factor when comparing wireless router and Ethernet cable. The data on an Ethernet cable can only be accessed by devices physically attached to the network. These devices, including laptop at one end and router at the other end, need firewall to protect them to make your wired home network safe. However, with WiFi, the data is in the air. If you’re using an open network, such as in a coffee shop, then all the data you send and receive can be intercepted, including personal information and login details, which could be easily stolen by hackers or identity thief.

Interference

WiFi is susceptible to countless environmental factors. Radio waves can be blocked by walls and floors. Other wireless devices can interfere with the signal, including things you wouldn’t think of, like microwaves and cordless phones, as well as nearby routers using the same channel. These inferences result in inconsistent performance. As you move around your home, you can see the strength of your WiFi network connection falls and rises, affecting speed accordingly. Ethernet Cable can also experience signal degradation, but it’s easier to manage and avoid. And, once you’ve got things set up properly, they should just continue to work without experiencing seemingly random signal degradation.

Conclusion

Although wireless router has gained much popularity with its convenience, Ethernet cable which takes some unique advantages still cannot be replaced. This post does not mean that you should ditch one over the other. A good home network will often have both wireless and wired components. Ethernet cable is great for high-speed transfers on desktop or other devices that do not move. Your smart phone, tablet, or laptop will benefit from a wireless router that has been properly configured to ensure a secure browsing experience.

How to Achieve High-Density and Easy Cable Management?

Increasing demand for data to support streaming media and the increasing usage of mobile broadband communications has resulted in dramatic advances in networking, such as 40/100G Ethernet solutions, which forces data center administrators to face new challenges, maintaining high availability, reducing costs, seeking out high efficiencies and planning for future growth. But when we pursue these goals to maximize density, capacity and performance, cable management could get out of control. High-density fiber connectivity products are the key to make high density a reality without sacrificing streamlined, cost-efficient cable management. The following text will introduce some high-density fiber connectivity components that make up a data center, and the features that can ensure easy cable management along the way.

High-Density Fiber Patch Cable

For standard fiber patch cable, which offers a small overall diameter can improve cable management by installing in dense patch cord trays that take up less space. It also provides better airflow to maintain consistent operating temperatures, reducing the likelihood of failure or downtime. But as cabling density increases, finger access to each patch cable become difficult. To solve this issue, high-density patch cords which deploy a flexible push-pull tab as shown below come into being. These tabs can help increase cabling density and maintain reliability, preventing you from accidentally loosening surrounding connectors as you access the patch cord you need.

High-Density Trunk Cable

High-density trunks allow tighter trunk cable bends for slack storage and routing. When you can find high-density trunks that offer smaller/tighter transitions, less space is consumed and installation will be easier. Besides, when a cable with a smaller overall diameter is used, cable pulling and cable management are improved. MPO or MTP trunk cable as shown below is commonly used trunk types.

High-Density Patch Panel

Crucial for organizing a fiber network, the high-density patch panel provides a centralized location to manage network connections. Not only does it provide physical security for sensitive network connections, it also minimize network downtime by allowing easy access during routine maintenance. It is an ideal solution for installation with space constraints, which is available in flat and angled designs as shown in the image below, with 48 ports in one rack spaces and 72 ports in two rack spaces. The angled design increases rack density, managing high-density applications in one-fourth the area needed for conventional cable management systems.

High-Density Fiber Enclosure

High-density fiber enclosure increases fiber density by up to 50 percent within the same rack space for additional interconnect or cross-connect patching. It is ideal for data center and enterprise applications where network expansion is a priority, now and in the future, and this scalable solution allows you to increase port density in racks to meet expanding network demands. Fiber optic enclosure often comes in two versions: wall mount fiber enclosure and rack mount fiber enclosure as shown below. Typically, wall mount enclosure can be installed directly on wall for fiber cabling, while rack mount enclosure usually has a industry standard 19 inch wide rack unit design and can be installed on a rack for fiber cabling. For higher fiber count, the rack mount enclosure could be 2/4/6/12 rack unit or more.

Summary

Existing and emerging network technologies are driving the need for increased data rates and fiber use in the data center. High-density optical connectivity solutions are essential to address these trends and to facilitate the efficiency of cable management. The products we introduced above are common in a high-density data center. You can choose the right one according to your requirement.

Why We Choose Tight-Buffered Cable Over Loose-Tube Cable for Indoor/Outdoor Applications?

With local area network (LAN) reaching out further into the campus environment, often linking multiple buildings within short spans, the cable market is seeing an increased demand for a fiber optic cable suitable for both indoor and outdoor applications. In the past years, a number of manufacturers have introduced indoor/outdoor cable to answer the market’s call. Indoor/outdoor fiber optic cable that is capable of surviving the outdoor environment and meets the flammability requirements for use inside buildings offers many advantages to the end-user, as well as the installer and distributor. The use of this type of cable between and within buildings can save many labor hours and reduce material costs by eliminating the need to splice outdoor cables to flame-retardant indoor cables. Generally, indoor/outdoor cable is available in two designs: loose-tube and tight-buffered. But why we are more prone to tight-buffered cable instead of loose-tube cable? Read the following text, and you will get the detailed answer.

Advantages of Tight-Buffered Cable Over Loose-Tube Cable

Both tight-buffered and loose-tube cable have been available on the market for many years. However, loose-tube cable has its roots in outside-plant applications, while tight-buffered cable is typically used for applications. And most manufacturers of indoor/outdoor cable is to refine the design of loose-tube cable to make it suitable for interior use. But there are some unique advantages taken by tight-buffered cable instead of loose-tube cable.

Lower Termination and Splicing Cost

Termination and splicing cost of fiber optic cable can be one of the largest line items in an installation budget. A large number of products and alternative approaches make it possible to devise system layouts with considerable variations in installed costs. Historically, loose-tube gel-filled cable has been used for outdoor long-haul routes. Due to the fragile bare fibers and gel filling, which must be cleaned prior to termination, loose-tube gel-filled cable is the most difficult to splice and terminate and also has the highest termination material costs. Besides, this cable type must normally be terminated or spliced close to the cable entryway of a building to switch to indoor-style cable, as it is generally incompatible with indoor fire codes. Since fibers within the loose-tube gel-filled cable typically have a 250um coating, care must be taken to avoid damaging the fibers when removing the outer cable jacket and buffered tubes, as well as when the fiber is being cleaned or spliced. This time consuming and labor intensive process adds hidden costs to the installation of loose-tube gel-filled cable for indoor/outdoor use, and it creates another future failure point.

On the contrary, for tight-buffered cable, each fiber inside it is protected with its own 900um diameter buffer structure, which is nearly four times the diameter and six times thickness of 250un coating. This construction feature contributes to the excellent moisture and temperature performance of the tight-buffered indoor-outdoor cables and also permits their direct termination with connectors. The following image shows the different inner structure of tight-buffered and loose-tube cable.

Reliability

Reliability is another factor that we choose tight-buffered cable. Splicing is the weakest link in a fiber optic cable installation. During the splice operation, the fiber is stripped of all its cable, coating, and buffering protection, leaving the bare fiber open to dust, dirt, water vapor, and handling, which could reduce fiber strength and increase brittleness. Besides, the splices inside buildings may be held in a cabinet that is open to the air and may be located in a basement near a building entrance or in an electrical closet, both of which are uncontrolled environments, which leads to the splices being the item with the greatest failure rate in the cable system. However, as we have mentioned above, with tight-buffered cable, the splicing is eliminated and the installation reliability is greatly improved.

Maintenance

With tight-buffered indoor/outdoor cable, it can greatly simplifies maintenance and reduces restoration time. For routine terminations often require in moves, additions, and changes, only the skills and tooling for installing optical connectors are needed. However, loose-tube cable requires splicing with all the associated tooling and skills. Tight-buffered cable allows some portion of the fibers to be left dark for future termination with whatever type of connectors may be required. The installation of connectors terminated with the ends of optical fiber if the minimum skill required of the organization responsible for maintenance of a fiber optic cable plant.

Summary

Indoor/out door tight buffered cabling is gaining popularity in the campus deployment, since it can save time and labor by bringing one cable from an outside plant setting into a building without having to perform a transition splice. FS.COM provides a wide range of indoor/outdoor tight-buffered cables for your reference, like breakout fiber optic cable and fiber distribution cables. If you have related demand, kindly visit FS.COM.

100G Single-Mode Modules for Short Distance Transmission

As bandwidth demand continues to grow, network service providers are looking at 100G Ethernet network to accommodate the constant traffic surge. This new technology translates into greater speeds and a possible network infrastructure upgrade to compensate for various challenges that do not apply to slower networks, such as 10G, or 40G. 100G Ethernet provides high-speed connectivity while protecting current network infrastructures that requires broad expertise and wide-range testing to qualify the state of the fiber, perform fiber characterization and assess the integrity of data transmission over long-haul and ultra-long-haul networks. In response to 100 Gigabit Ethernet, many famous telecommunication companies, like Cisco, have delivered industry-leading, standards-compliant, 100G pluggable transceiver modules, such as single-mode QSFP-100G-LR4 for the transmission distance up to 10 km and multimode QSFP-100G-SR4 for the transmission up to 100 m. How about single-mode 100G modules for the transmission distance less than 2 km? Today, we’re going to introduce two 100G interfaces over single-mode fiber for short distance transmission: 100GBase CWDM4 and 100GBase PSM4.

The Development History of 100GBase CWDM4 and 100GBase PSM4

The IEEE standardized a cost-effective 100m solution known as “SR4”. Beyond 100m, there is only the “LR4” standard, which is targeted to achieve 10km. Customers, particularly hyperscale data centers are looking for solutions up to 2 km. To response, in 2014, a new industry group CWDM4(coarse wavelength division multiplexed 4x25G multi-source agreement) MSA which is consisted of Avago Technologies, Finisar Corp, JDSU, Oclaro, and Sumitomo Electric, announced the formation of an industry consortisum dedicated to defining specifications and promoting adoption of interoperable 2km 100 interfaces over duplex single-mode fiber, which smooths the process of getting to 100Gb Ethernet.

Like the development history of 100GBase-CWDM4, in order to fill the requirement of low-cost 100G connections at reaches of 500 m in applications that fall in between the IEEE standardized multi-wavelength 10-km 100GBase-LR4 single-mode approach and its multimode-fiber based 100GBase-SR10 short reach specification, six technology vendors aim to promote the creation and adoption of parallel single-mode 4-lane (PSM4) approach to 100G in the data center.

Main Features of 100GBase-CWDM4 and 100GBase-PSM4

100GBase-CWDM4: 100GBase CWDM4 module comply with the requirement of CWDM4 MSA. It is a 100G optical module using CWDM (coarse wavelength division multiplexing) technology with 4 lanes of 25Gbps optically multiplexed onto demultiplexed from a standard duplex G.652 single-mode LC or SC fiber for the link length from 2 meters to at least 2 kilometers. Transceiver modules compliant to CWDM4 MSA specification use a color code to indicate the application. The color code can be on a module bail latch, pull lab, or other visible feature of the module when installed in a system The image below shows the working principle of 100GBase-CWDM4.

100GBase-PSM4: 100GBase-PSM4 is a parallel module which provides increased port density, offering four independent transmit and receive channels, and each channel operates at 25Gbps, resulting in an aggregate data rate of 100Gbps for optical communication applications. It can support the link length up to 500 m over single-mode MPO or MTP fiber. The working principle of 100GBase-PSM4 is shown below.

Which One Is More Cost Effective?

From an optical transceiver module structure viewpoint, PSM4 can be more cost effective, this comes in two reasons: One is that it uses a single uncooled CW laser which splits its output power into four integrated silicon modulators, the other is that its array-fiber coupling to an MTP connectors is relatively simple.

However, from an infrastructure viewpoint, PSM4 would be more expensive when the link distance is long, mainly due to the fact that PSM4 uses 8 optical single-mode fibers, while CWDM4 uses only 2 optical single-mode fibers.

When take these two factors into considerations, a total cost comparison can be qualitatively shown in the figure below. As can be seen in the figure, PSM4 starts with a lower cost due to its lower transceiver cost, but as the link distance increases, its total cost climbs up very fast due to the fact that it uses 8 optical fibers. Besides, if deploying PSM4 modules, the entire optical fiber infrastructure within a data center, including patch panels, has to be changed to accommodate MTP connectors and regular single-mode fiber cables. In addition, cleaning MTP connector is not a straightforward task.

Conclusion

With the requirement for longer distances and higher data transmission speed increases, 100GBase-CWDM4 and 100GBase PSM4 which provide lower-cost, lower power option for what can be referred to as medium-reach distances that is future-proof for the next generations of data transmission speeds. FS.COM offers compatible 100GBase-CWDM4 and 100GBase-PSM4 for many brands at affordable price. You can choose the right one according to your need.

Take Fiber Optic Connector Cleaning Seriously

Fiber optics infrastructures have become quite common in a number of markets and applications. In conjunction with this fiber infrastructure are a variety of fiber interconnect solutions. Clean, reliable optical connector are paramount in maintaining the high performance and stability of the whole network. Routinely inspecting and cleaning fiber optic cleaner is very essential for the fiber infrastructure.

Why Should We Attach Importance to Fiber Optic Connector Cleaning?

Fiber optic communications rely on very small fibers to carry beams of light. Most fiber optic cores are between 9 um and 62.5 um in diameter, much thinner than the typical strand of human hair, which is about 90 um in diameter. Because of its small diameter, even the tiniest bit of dust, dirt, oil, or other contaminates can degrade an optical signal. Fiber optic cable contains many fibers and are designed with the knowledge that some fibers will be occluded by dirt or other contaminates at some point. However, most can only afford so much blockage before they become ineffective, resulting in diminished service or even down time for the networks they serve. Slow connections and downtime can be costly for business relying on their fiber optic networks. That’s why keeping connectors clean is so important.

How Does the Fiber Optic Connector Get Contaminated?

Dust and oils are the two most common forms of contamination on fiber connectors and can come from a variety of normal maintenance activities. Oils from your fingers will leave a noticeable defect easily seen with the use of a fiber scope, the oil will also tend to trap dust against the fiber, which can result in scratches on both the fiber connector and the optic it is being mated to. Inserting and removing a fiber tends to create a small static charge on the ends, which can result in the attraction of airborne dust particles. Simply removing and re-inserting a fiber has the possibility of contaminating the end of the connector in a facility that may have a higher level of dust(newly constructed or renovated data center).

Common Methods Used for Fiber Optic Connector Cleaning

There are a variety of methods deployed to clean fiber optic connectors, some more effective than others. Here will introduce two common methods and some cleaning tools.

Dry Cleaning Method

Dry cleaning is a type of cleaning method which does not require the use of any solvent. One-click fiber cleaner, MTP/MPO cleaner, and cassette cleaner are tools using dry cleaning method.

One-Click Fiber Cleaner for LC/SC Connector: One-click fiber cleaner as shown below or fiber cleaning pen is an affordable and effective way to clean LC/SC style optical connectors. Inserting the head into the adapter and pushing until the “click” removes dust by swabbing the fiber. At around $19 for 800 times use, it is a must-have for fiber cleaning. (Note: for pinned connections, a different tool that accommodates the pinned adapter is required.)

One-Click Fiber Cleaner for MPO/MTP Connector: This type of one-click cleaner is also called as MPO or MTP cleaner as shown below. It comes with a barrel on the end for cleaning both connectors and endpoints. It works in the same way as the reel cleaner with a refillable “tape” used to clean but works on both the fiber and the port allowing for quick and easy cleaning.

Fiber Optic Cassette Cleaner: Dry cleaning without alcohol in palm size housing with cleaning around 500 times for the male connectors only without solvents left and second pollution. The cassette cleaner as shown in the following image can be reused by replacing the cleaning reel/cartridge to reduce the general cost.

Wet Cleaning Method

Wet cleaning is another type of cleaning method which requires the use of a solvent such as isopropyl alcohol.

Lint-Free Isopropyl Alcohol Wipes: Gently wiping fiber connectors with these wipes as shown below is the most effective way to remove resistant dust particles, oil or other contamination. When the dust and isoprophyl alcohol make contact, the duct is pulled into the alcohol, and the wipe clears both the dust and liquid from the fiber surface.

Note: Once a fiber optic connector is cleaned, it’s best to reconnect it immediately or cover it with a cap to ensure it will not get dirty again.

Summary

Keeping fiber connector clean is essential for the reliability of the whole network. We have introduced four types of fiber optic cleaners. Each cleaner has its own features, also you have your own references for fiber cleaning work, more detailed information of the specific cleaner or material, you may turn to FS.COM.

RJ45 Connector for Ethernet Cable Termination

It is known that fiber optic cable is often used fiber optic connector, like LC, SC, to achieve termination. How about Ethernet cables? That is RJ45 connector or RJ45 plug, which is a common component terminated with Ethernet cables to achieve the connection between computer and Ethernet-based local area network(LAN). The letter “RJ” means registered jack, which is a standardized telecommunication network interface for connecting voice and data equipment to a service provided by local exchange carrier or long distance carrier. This post aims to introduce this type of Ethernet connector and offers some simple guidance for terminating Ethernet cable with RJ45 connectors.

What Is RJ45 Connector?

RJ45 is the commonly used twisted-pair connector for Ethernet cable and networks. It is usually made of a transparent plastic piece with eight pins on the port as shown below. Four of the pins are used for sending and receiving data, and the other four are used for other technologies or power networking devices. So this type of connector is also called as 8P8C (Eight Position, Eight Contact) modular connector. It can be inserted along a fixed direction and automatically prevent shedding used for most applications, such as Ethernet networking, telecommunications, factory automation and so on. The RJ45 is originally invented to replace the bulkier connector for connecting modems to telephones in the telecommunication industry, but nowadays, it is most commonly applied for networking devices including Ethernet cables, modems, computers, laptops, etc.

Differences Between RJ45 and RJ11

Besides RJ45, there are many other types of RJ-style connectors on the market, RJ11 is one of them. RJ11 connector has similar appearance as RJ45, so people often mix them together. Actually, these two connector types have their own specific purposes. The biggest difference between them is in where they are actually used. RJ45 connector is used in networking, where you connect computers or other network elements to each other, while RJ11 is the cable connector that is being used in telephone sets.

Aside from the application, there are also differences that an individual can easily see and identify. The first of which is in the number of cables that are accommodated in each connector. If you look closely at both connectors, you would see that there are only four wires inside the RJ11, while eight wires inside an RJ45. As a consequences of having to accommodate more wires, RJ45 is a little bit bigger than RJ11. You should keep in mind although it is possible to physically fit an RJ11 connector into an RJ45 receptacle, this will never function for an actual Ethernet connection, or you will damage the device that has the RJ45 slot. We can see their differences in the image below.

RJ45 Wiring Diagram For Ethernet Cable

According to ANSI, TIA & EIA, there are two variations of RJ45 wiring diagram: T568A and T568B. Both T568A and T568B provide wiring schemes for terminating twisted-pair copper network cable to RJ45 connectors. The pairs in these cables consist of four colors (blue, orange, green, and brown), with each pair includes a solid-colored wire twisted with a wire of the same color, with white stripes.

When looking closely at the two wring diagrams below, the only visual difference between T568A and T568B is that the pin positions for the green and orange pairs are flipped as shown below. Besides the color placement variances, there are a couple of compatibility factors that can affect the choice of an RJ45 wiring scheme. T568B is a more up-to-date scheme and also the most widely chosen wiring schematic, because it matches AT & T’s old 258A color codes, meanwhile, T568B accommodates for current and future needs.

When building a new network, one may technically pick any one of the wiring schemes. No one scheme is better than the other, or is better suited for specific things. Both schemes are perfectly fitted for any installation type. But when an existing network is being expanded, it is crucial to use the scheme in place.

How to Terminate Ethernet Cable With RJ45 Connector?

Step1: Using a crimping tool, trim the end of the cable you’re terminating, to ensure that the ends of the conducting wires are even. Then strip off approximately 1 inch of the cable’s jacket.

Step2: Separating the 4 twisted wire pairs from each other, then unwind each pair, so that you end up with 8 individual wires. Flatten the wires out as much as possible, since they’ll need to be very straight for proper insertion into the connector.

Step3: Holding the RJ45 connector, so that its pins are facing away from you. Moving from the left to right, rearrange the wires according to the wiring scheme.

Step4: Holding the connector, and carefully insert the wires into the connector, pushing through until the wire ends emerge from the pins. Check to make sure that the wire ends are in the correct order. If not, repeat the steps2 to step3 again.

Step5: Inserting the prepared connector/cable assembly into the RJ45 slot in your crimping tool. Firmly squeeze the crimper’s handles together until you can’t go any further.

Step6: Carefully cut wire ends to make them as flush with the connector’s surface as possible.

Step7: To make sure you’ve successfully terminated each end of the cable, use a cable tester to test each pin.

Conclusion

The RJ45 plug, with easy plug-and-play style, reducing the difficulty of installation, is one of the most popular connector type nowadays. A lot of people have begun to place RJ45 connectors on wall outlet inside their houses in order to reduce the number of visible wiring. Hope this post can help you better understand RJ45 connector and how to use them to terminate Ethernet cables.

Choosing the Proper Polarity Method for MTP System

Whether in local area network (LAN) campus or data center backbones, we are in the process of migrating to higher-density cabling in order to meet system bandwidth needs and provide the highest broadband network connectivity density. Many network designers are turning to MTP trunk cable for today’s duplex fiber transmission and to provide an easy migration path for future data rates that will use parallel optics such as 40/100G Ethernet. To ensure reliable MTP system performance as well as support ease of installation, maintenance and reconfiguration, choosing the proper polarity method is very important. In this post, we are going to introduce three MTP polarity method for your reference.

What Is Polarity?

Polarity is the term used in the TIA-568 standards to explain how fiber (wire) to make sure each transmitter is connected to a receiver on the other end of a multi-fiber cable. To be specific, as we all know, optical fiber links typically require two fibers to make a complete circuit. Optical transceivers have a transmit side and receive side, and typically deploy a duplex fiber connector as the interface. In any installation, it is important to ensure that the optical transmitter at one end is connected to the optical receiver at the other. This matching of the transmit signal (Tx) to the receive equipment (Rx) at both ends of the fiber optic link is referred to as polarity.

Structure of MTP Multi-fiber Connector

To better understand each polarity method, it is important to make it clear for the MTP connector structure.

Each MTP connector has a key on one side of the connector body. When the key sits on top, this is referred to as the key up position, on the contrary, when the key sits on bottom, we call it key down position. Each of the fiber holes in the connector is numbered in sequence from left to right, and we call these fiber holes as positions, or P1, P2, etc. Besides, there is a white dot as shown below on the connector body to designate the position 1 side of the connector when it is plugged in. Generally, MTP multi-fiber connector is pin and socket connector—requiring a male side and a female side (male side has pins, while female side has no pins) as shown below. Cassette and hydra cable assemblies are typically manufactured with a male connector, while trunk cable assemblies typically support a female connector.

Three Polarity Methods for MTP System

Defined by TIA/EIA-568-B.1-7, there are three polarity methods for MTP system—method A, method B and method C. These methods define installation and polarity management practices, and provide guidance in the deployment of these types of MTP fiber links. Once a method is chosen, these practices must be put into place to insure proper signaling throughout the installation.

Method A: In method, it requires two type A cassettes with key-up to key-down adapters, a straight-through key-up to key-down MTP trunk cables as well as two patch cables. This method, shown below maintains registration of Fiber 1 throughout the optical circuit. Fiber 1 in the near end cassette mates to Fiber 1 in the trunk cable assembly, which mates to Fiber 1 in the remote cassette. The fiber circuit is completed by utilizing one “A-to-A” patch cord at the beginning and “A-to-B” patch cord to insure proper transceiver orientation.

Pros: It provides the simplest deployment, works for single-mode and multimode channels, and easily supports network extensions.

Cons: Requires pre-configured “A-to-A” patch cables, or field configuration of same.

Method B: In type B polarity method, method B cassette requires key-up to key-up adapters to link reversed cable or MTP trunk cable type B. The fiber circuit is completed by utilizing straight “A-to-B” patch cords at the beginning and end of the link, and all of the array connectors are mated key-up to key-up. This type of array mating results in an inversion, meaning that Fiber one is mated with Fiber twelve, Fiber two is mated with Fiber eleven, etc. To ensure proper transceiver operation with this configuration, one of the cassette needs to be physically inverted internally, so Fiber twelve is mated with Fiber one at the end of the link.

Pros: It requires single source for components and “A-to-B” patch cords only. Besides, it is a standard which provides migration path to parallel optics.

Cons: This key-up to key-up method requires a more in-depth planning stage in order to properly manage the polarity of the links, and to identify where the actual inversions need to occur. Moreover, it only support multimode fiber.

Type C: The method C shown below, with the key-up to key-down adapter in the cassette, looks like the type A method. However, the difference between this method and method A is that the flip does not happen in the end patch cords, but in the array cable itself. In this case, the fiber at position 1 on one end of the cable is shifted to position 2 at the other end of the cable. The fiber at position 2 at one end if shifted to position 1 at the opposite end, etc.

Pros: This method requires one cassette type, easy to produce and purchase, and it can support both single-mode and multimode fiber.

Cons: An additional drawback to this method is that it does not support parallel optics and is less reliable than method A.

Conclusion

We have discussed three polarity methods for MTP system, and indicate the pros and cons of each one. For choosing the proper method for MTP system, you should weight both advantages and disadvantages.