Bend Radius—How It Can Impact Your Cable Performance?

Why should fiber optic cable not be tightly bent? Are fiber optic cable fragile? These issues are what users care about when deploying fiber patch cables. Usually, fiber optic cable is made from two bend sensitive materials: plastic or glass. It is broken easily when kinked or bent too tightly to exceed the minimum bend radius of cable. Then which factor will influence bend radius? How to choose cables according to it? This blog will provide some hints.

Why Bend Radius Is Important?

When you deploy the fiber optic cable, it is inevitable to flex, pull and bend it due to the practical conditions. However, it is the bend radius that determines how much you can bend a cable. It represents as the safe value that can prevent your cable from damaging or degrading its performance. If a cable is bent beyond its allowed radius, it will generate crosstalk or interference in data transmission, or even shorten its life. That’s why it’s important to know the bend radius of the cables, especially the minimum bend radius,which is the smallest allowed radius the cable can be bent around without signal loss or impairment.

bend radius of cable

Factors Impact Bend Radius of Cable

The bend radius may differ from cables. The fact is the smaller the minimum bend radius, the more flexible the cable. Here list some factors that may affect this radius of cable.

  • Outer Jacket Thickness

The thickness of the outer jacket of a fiber patch cable intended for bending will influence the potential minimum curve radius. Generally speaking, if the outer jacket is thick, the fiber patch cable will have a smaller bend radius. This can be translated by the fact that when the cable is bent, the stretching force makes the outer jacket thinner and even broken. Therefore, if the outer jacket is thin itself, the external tension may deform of break the fragile cable.

  • Material Ductility

Cables are manufactured by different materials, and this will affect the radius of the bend. Ductility refers to the flexibility of material under tensile stress or stretching force. If you would like to obtain small curve radius, you should choose cables made of highly ductile materials like copper. An alternative such as glass is more brittle than flexible.

  • Core Diameter

The large core diameter determines the small bend radius. Simply put, the single mode fiber has a smaller diameter than multimode fiber, and the single mode fiber cable bears less weight or bending than multimode fiber cable. That’s why the bending radius of single mode fiber optic cable is larger than the multimode fiber optic cable.

How to Choose Fiber Optic Cables based on Bend Radius?

Generally, the multimode fiber optic cable is recommended if the bend radius is the only consideration. And another option is BIF fiber cable. BIF means the bend insensitive fiber which enables tight curve radius when cables are bent or twisted. FS adopts it in producing both multimode and single mode fiber cables to endow them much smaller bend radii than ever before. It realizes more convenience in cable management, as well as less signal loss and less cable damaging. Here is a bend radius chart of BIF fiber optic cable.

Fiber Cable Type
Minimum Bend Radius
OM3/OM4 MTP BIF
7.5mm
Single Mode OS2 MTP BIF
10mm
Uniboot OS2 LC BIF
10mm
Uniboot OM3/OM4 LC BIF
7.5mm

Conclusion

To sum up, the bend radius of cables is paramount for fiber patch cable installations. Factors which influence the minimum radius of fiber optic cable include the outer jacket thickness, material ductility and core diameter. To protect the integrity and performance of cable, we shall not bend the cable beyond its allowed radius.

Good Forecasts for Global Optical Fiber Cable Market

An optical fiber cable uses light wave for voice and data transmission, its data transmission capacity is 4.5 times more than conventional copper cables. So in the past several decades, we have seen that fiber optic cables are superior to traditional copper twisted-pair cable or coaxial cable because of its unique physical characteristics, allowing information to travel at speeds increasingly approaching the speed of light without interference between adjacent wavelengths. In leading market, the global drive to implement FTTx into more new venues is good news for the market of optical fiber cables. Another good trend is that the price erosion of optical fiber cables had been 10 to 15 percent annually, in result that the demand of optical fiber cable is expected to continue growing in the foreseeable future. And the growing data transmission workloads placed by high-performance computers, servers and network storage systems is helping spur growth in the market. Consequently, fiber optic cables are now the indispensable backbone of today’s communication network. This article will analyse the global optical fiber cable market in three main applications, including long-distance communication, submarine cable and FTTx network.

fiber

Global Optical Fiber Cable Market to Grow at 9.8% till 2021

According to the report “Fiber Optics Market by Cable – Global Forecast to 2021”, the optical fiber cable market is anticipate to grow at a CAGR of over 9.8% during 2016-2021. The growing importance of cloud computing, data transfer & storage, and IoT is driving the use of Internet, which is driving the fiber optic cable market, as it acts as the backbone for data transmission. Moreover, growing technological advancements increase in number of connected devices and data centers are expected to positively influence global optical fiber cable market. In addition, next generation technologies such as LTE and FTTx, which require last mile connectivity, is expected to propel the demand for optical fiber cables in the coming years. All these factors have led to an increase in Internet users, which in turn has led to the higher usage of optical fiber cable to transfer information over the Internet, thus driving the fiber optics market.

Global Optical Fiber Cable Market

Global Optical Fiber Cable Demand from 2012 to 2018 (Source: Statista)

Optical Fiber Cable Market in Long-distance Communication

Currently, the growing adoption of optical technology in the telecommunications appears to be promising. Optical fiber has virtually unlimited capacity and low signal attenuation allowing long distances without amplifier or repeater, no exposure to parasite signals or crosstalk, and no electromagnetic interference (EMI). So fiber optic cable is especially advantageous for high-speed data transfer services in long-distance communications over electrical cabling. Furthermore, the increasing cloud-based applications, audio-video services, and Video-on-Demand (VoD) services further stimulate the demand for optical fiber cable installations.

Growing Need for Capacity

Growing Need for Capacity (Source: Goldmedia)

Submarine Optical Fiber Cable Market

Submarine optical fiber cables are undersea cables used for carrying data across interconnected networks between continents. With the advancements of technology, most of the submarine optical fiber cables that currently form the backbone of the Internet connect the U.S. to Europe and Asia by crossing the Atlantic or Pacific oceans. Instead, there is a proposal for deployment of Trans-polar submarine cable system in Arctic Ocean. Laying an undersea fiber optic cable is meant to connect Asia and Europe by crossing the Arctic Circle – the shortest practical distance yet for Internet signals traveling between the two continents. According to the report by Global Industry Analysts (GIA), cumulative installations of submarine optical fiber cables globally are projected to reach 2 million kilometers by 2020, driven by the growing demand for fiber broadband and the ensuing deployment of fiber optic cables in the Internet backbone. Presently, submarine optical fiber cables transmit 100% of the international Internet traffic, and more than 95% of the world’s combined data and voice traffic.

Submarine_Fiber_Cable_Market

Submarine Optical Fiber Cable Market (Source: Technavio)

Optical Fiber Cable Market in FTTx Networks

In recent years, the market for optical fiber cable has shifted dramatically to local deployments, away from long haul and regional. This is the impact of FTTx, which calls for far more dense applications in neighborhoods, cities and other highly focused areas. Optical fiber cable is being caught up in the global move to broadband in the near future. The next generation of high bandwidth applications, along with the proliferation of connected devices, is expected to require faster and higher bandwidth networks which will require the use of multimode fiber cable for data transfer. This growth in the FTTx networks in turn is expected to drive the fiber optics market. Future Market Insights (FMI) forecasts the global fiber to the home (FTTH) market’s value will grow from $9.5 billion in 2017 to more than $37 billion by the end of 2027, a 14.4% compound annual growth rate (CAGR). In the leading Asian economies, more than 44% of all homes and buildings are already directly connected to the fiber optic cable network; in North America penetration is 8.4%, in Europe 5.6%.

fiber-optic-cable-in-fttx

Final Thought

Fiber optic cable is widely used for data transmission and is increasingly being used in place of metal wires because of its efficiency and high transmission capacity. Since the use and demand for great bandwidth and fast speed, there is no doubt that fiber optic transmission will bring more opportunities and be continuously researched and expanded to cater for future demands. However, although fiber optic cable in itself is considered a long-term stable investment, it also faces huge challenge. The major restraint in the fiber optics market is the growing use of wireless communications systems in remote areas.

Related Article: The Advantages and Disadvantages of Fiber Optic Transmission

Brief Introduction to Ribbon Fiber Optic Cable

In order to meet the increasing system bandwidth needs, local area network (LAN) campus and building backbones, as well as data center backbones, are migrating to higher cabled fiber counts. Ribbon fiber optic cables can offer the highest fiber density relative to cable size, maximize utilization of pathway and spaces and facilitate ease of termination, which makes them an ideal solution for the need. This post mainly focuses on the benefits and applications of ribbon fiber optic cable.

Ribbon Fiber Optic Cable Design

Ribbon fiber optic cable is a type of cable widely deployed in campus, building and data center backbone applications where high fiber counts are required. There are 8 fibers, 12 fibers, 24 fibers and other higher fiber counts available on the market. At present the 12-fiber ribbons are readily accessible and identifiable with ribbon identification numbers and TIA-598 compliant fiber color coding, which make it prevalent in today’s networks. Usually there are two kinds of outer jacket of ribbon fiber optic cables: non-flame-retardant and formulated flame-retardant. The former is often used in outside plant applications, while the latter is typically used for indoor applications. Here is an example of ribbon fiber optic cable construction.

ribbon fiber optic cable

Benefits of Ribbon Fiber Optic Cable

As we all know, stranded loose-tube and ribbon fiber optic cables are staples of the outside plant applications. Both of them perform well in harsh outdoor environments, and both are available in a multitude of configurations, including: all-dielectric, armored, aerial self-supporting, etc. However, when compared to stranded loose-tube cable designs, the ribbon fiber design offers robust performance equivalent to the stranded loose-tube cable, and provides the maximum fiber density relative to cable diameter. The chief distinction between these cables is the manner in which the individual fibers themselves are packaged and managed within the cable. A ribbon fiber cable has the individual fibers precisely bonded together in a matrix that might encompass as few as four or as many as 24 fibers. In contrast, a loose-tube cable has between 2 to 24 individual fibers housed in multiple buffer tubes with each fiber detached from the other.

ribbon fiber optic cable vs loose tube cable

It’s the special ribbon fiber design that makes ribbon fiber optic cable offer more advantages over loose-tube designs in many applications.

  • Ribbon fiber optic cable can be prepped and spliced much more rapidly than loose tube cables. That’s means less installation time, less installation labor cost and significantly less emergency restoration time.
  • Ribbon fiber optic cables enable a smaller footprint in splice closures and telecommunications room fiber management.
  • Ribbon cables offer greater packing density in higher fiber counts which enables more efficient use of limited duct space.
  • Ribbon cables are typically very cost competitive in counts above 96 fibers.
Ribbon Fiber Optic Cable Application

Although there are various fiber counts available with ribbon fiber optic cable, the 12-fiber ribbon cables are the most commonly used ones. With the introduction of innovations such as ribbon splitting tools and field-installable 12-fiber array connectors, 12-fiber ribbons are easily terminated with simplex and duplex connectors such as LC or SC connectors or with the MTP connector. The MTP connector is a 12-fiber push/pull optical connector with a footprint similar to the common simplex connector. Many users like to apply MTP connectors to ensure the highest quality connector insertion loss and return loss performance and to expedite the cable installation.

In order to illustrate how ribbon fiber optic cables are deployed, here take the termination of MTP connectorized ribbon cable with patch panel as an example.

The termination is normally used in an interconnect application where a harness assembly is used on the front of the patch panel. We know the MTP fiber cable has 12-fiber MTP connector on one end of the cable and simplex or duplex style connectors on the other end. Just like the picture below shows.

mtp-harness-assemblies

Except for the application noted above, ribbon fiber optic cables also can be used in both interconnect and cross-connect applications where an MTP connector module cassette is used. And they can be applied to pathways and spaces.

Conclusion

Ribbon fiber optic cables deliver high fiber density in the most compact cable package possible. And they also maximize the number of fibers that can be deployed in a limited space while streamlining fiber termination. At the same time they can save time and money with easy mass fusion splicing. Ribbon fiber cable is now easily obtained using traditional simplex or duplex connectors as well as MTP Connectors, which make them suitable for various applications.

Getting More Benefits From Sensing Fiber Optic Cables

Sensing fiber optic cable is a type of optical cable that can monitor temperature, strain, acoustics and pressure. They are suitable for a wide range of applications like fire detection, vibration monitoring, industrial plant temperature sensing, temperature gradients in soil, pipeline leak and intrusion detection. Although these cables are built based on standard fiber optic cable which only operates to 85℃, the highest working temperature of them is up to 700℃. Before knowing what benefits that sensing fiber optic cable could bring to our life, let’s figure out the common types of sensing optical cable at first.

PBT Tube Temperature Sensing Optical Cable

The major difference of this optical cable is that the bare fiber inside is protected by a PBT tube. Except that, it is comprised of fiber, oil, aramid yarn and a sheath which can be made of different materials such as PVC, LSZH, PU and PE. With the unique structure, this sensing fiber optic cable is suitable for applications in subway systems, tunnels and fire protection industries to sense temperature and pressure, helping to prevent disasters and accidents.

PBT tube temperature sensing fiber optic cable

Armored Temperature Detecting Sensor Cable

Armored fiber optic cable is very common in optical communication. However, this kind of armored sensing cable is a little different. They are strengthened by both SUS spring tube and SUS braiding, which bring them very good mechanical performance of tensile resistance and pressure resistance. Therefore, these cables are widely applied to fire detecting, building health detecting and temperature detecting.

Teflon Sheathed Sensor Cable

Teflon, or PTFE (Poly tetra fluoroethylene) is used in a wide variety of high temperature applications like gas turbine and high voltage gas ignition wires due to its higher melting point. Besides, the aramid yarn and stainless steel braiding ensure good crush-resistant performance and the tensile strength of the cable. With all these characteristics, Teflon sheathed sensor cable is a good choice for high temperature resistant environment and fiber temperature sensing systems.

Teflon sheathed sensing fiber optic cable

Seamless Tube Temperature Sensing Cable

This armored fiber optic cable consists of bare fiber, oil, seamless stainless steel tube and an outer jacket. This structure brings a high tensile strength, crush resistance, a compact size and an unmatched steel performance to this fiber cable. And it features a simple structure and small size, but providing prominent transmission performance. With this sensor cable, some accidents that frequently occur in places such as tanks and mines can be avoided.

Copper Braid Armored Sensor Cable

As its name shows, there is a copper braiding around the outer jacket of this sensing cable. Copper braid is made from weaving together strands of copper wire. The flexibility of the braid is determined by the diameter of the copper wire. The smaller the wire, the greater the flexibility. And the larger the volume occupied by the braid, the more expensive the braid becomes. Apart from the copper braiding, there are stainless steel flexible tube and stainless steel braiding outside the bare fiber, which make the cable more suitable for outdoor optical fiber communication and optical fiber sensor. With the copper braiding structure, the special cable can prevent the external electromagnetic field on internal invasion, reducing its optical transmission loss.

Copper braid armored sensing fiber optic cable

Silica Gel Sensing Optical Cable

Unlike copper braid armored sensor cable, the silica gel sensing optical cable has a very simple structure, including bare fiber, Teflon tube, armored yarn and silicone jacket. As have mentioned above, Teflon is a high performance alternative insulation. With the silica gel that is another kind of good insulation material, both of them make this sensing fiber optic cable an ideal solution for high temperature resistant and high voltage environment. It can work normally even in the 250℃ high temperature environment or 6kv high voltage environment without affecting optical signals’ transmission.

Summary

The deployment of sensing fiber optic cables brings us lots of benefits in various applications. They can be applied in downhole to monitor temperatures either as DTS or datacom links to sensors; they can be deployed in power distribution networks to monitor performance of power cable systems; they can be attached to pipelines for temperature data that’s available on demand. This post introduces six kinds of sensing fiber optic cable. All of them are available on FS.COM. Welcome to contact us via sales@fs.com.

Ruggedized Fiber Optic Cables for Harsh Environment

As a perfect choice for today’s telecommunication which requires a larger bandwidth, fiber optic cables have been widely put into use and get more popularity. However, when optical cables are increasingly used in different applications with diverse environments, for example, from indoor to tough environments, new and demanding requirements also have been put forward for them. Before deployment, several considerations may occur. For instance, can they resist the erosion of oil or chemicals? Can they still work normally in changeable weather? Do they have rodent-resistant ability? The answer of all the questions is yes. Today’s fiber optic cables possess various abilities to meet different requirements. Here is a brief introduction several ruggedized fiber optic cables that can work in different harsh environments, providing more conveniences and extra protection for network systems.

Armored Fiber Optic Cable

Armored fiber optic cable is one of the most commonly used cables to offer protection for fibers. Generally, armored fiber optic cable contains a helical stainless steel tap over a buffered fiber surrounded by a layer of aramid and stainless steel mesh with an outer jacket. With this unique construction, it can withstand the toughest environments—high temperatures, high pressures, and harsh vibrations as well as animals rodent and moisture. In a word, with the protection of flexible and durable steel tube, armored fiber patch cable will ensure the excellent operation of networks.

ruggedized-fiber-optic-cable-armored-cables

IP67 Waterproof Fiber Optic Cable

IP67 waterproof fiber optic cable is another kind of ruggedized cables used for outdoor applications. They are with strong PU jacket and stainless steel armor inside for future protection. “IP” in this term is a type of protection rating defined by International Standard IEC 60529. The number “6” and “7” mean this kind of cable possesses a good ability to resist dust and water. According to the connector types, the IP67 waterproof fiber optic cables have several types including IP67 MTP/MPO fiber cables, IP67 LC waterproof fiber cable and so on. IP67 waterproof fiber optic cables will not get damage even stepped, and are anti-rodents and suitable for use in harsh environment like communication towers and CATV (Community Antenna Television), providing protection for your networks. Here is a picture of IP67 LC component details.

ruggedized-fiber optic-cable-ip67-lc-commponent-details

Military Grade Fiber Optic Cable

Military grade fiber optic cable is the last type of ruggedized fiber cable to be introduced. They are manufactured with specialized military tactical fiber cable that has excellent impact and crush resistance characteristics, which comply with military requirements. Generally, they have an outdoor-rated polyurethane jacket that resists UV radiation, cuts, abrasions and chemicals, which is an ideal choice for military vehicles and field deployed communications equipment.

ruggedized-fiber-optic-cable-military-grade-fiber-cable

There is a multitude of challenges in military communications. Designed for uncompromising dependability in the harshest conditions, these military grade fiber optic cables are a cost-effective network alternative and can provide essential communications solutions for military applications, including greater bandwidth for real-time voice, data and video applications and easily deployable platform.

Summary

With the rapid development of optical communication around the world, more and more fiber optic cables are increasingly used in different environments. Under harsh conditions, the ruggedness and durability of common fiber optic cables cannot meet operators’ requirements, especially for exceptional demanding applications. This post mainly introduces three types of ruggedized fiber optic cable. All the cables mentioned above are available in FS.COM. If you have any problems about them, please contact us via sales@fs.com.

Things to Know About Bend Insensitive Multimode Fiber

Bend insensitive multimode fiber (BIMMF) has become a very active area within the telecommunication industry once it was introduced and popularized. It typically signifies technical advancements in the production of multimode optical fiber for easier installation, and cable management for multimode fiber cables through improvements in bend insensitivity. This article will focus on some useful information about BIMMF from the perspective of its working principle, performance in networking and unique advantages as well.

What Is Bend Insensitivity?

An optical fiber consists of a core and a cladding. Although both of these regions are made from glass in telecommunications grade fibers, they are significantly different from each other. Each region is designed to capture light within the core and transmit it to the opposite end of the fiber. During this process, the light may follow many paths, depending on the angle at which the light hits the boundary, it is either reflected back into the core, or it gets lost into the cladding. Therefore, the light losses during transmission cause a weaker optical signal at the other end.

light traveling in fiber

Optical fiber is sensitive to stress, particularly bending. When conventional fibers are bent tightly, some of the signal will leak out of the fiber at the site of the bend due to macrobend loss, which will results in system failure and unplanned downtime. Various attributes in the fiber determine when this occurs. The relative ease with which this happens is known as bend sensitivity. On the contrary, bend insensitivity is a positive feature that can provide for additional robustness and simplify installation of multimode fiber.

Introduction to Bend Insensitive Multimode Fiber (BIMMF)

Bend-insensitive multimode fiber (BIMMF) has an innovative core design that enables it to significantly reduce macrobend loss even in the most challenging bend scenarios. It is hence natural that bend insensitive multimode fiber can withstand tough treatment. The difference between traditional multimode fiber and BIMMF mainly lies in the fact that the BIMMF design can include an optical trench. This trench effectively improves the fiber’s macrobend performance by retaining more of the light that would have escaped the core of a traditional multimode fiber. So when compared with standard multimode fibers, BIMMF is proved to be a good candidate for loss and bend critical applications because of their higher immunity to bending losses, without loosing performances or compatibility to other standard high bandwidth multimode fibers.

Compatibility With Conventional Fibers

There is a lot of buzz around the issue of bend insensitive fiber— is it compatible with regular fibers? Can they be spliced or connected to other conventional fibers without problems? Modeling and testing on BIMMF has shown that an optimized BIMMF is backward compatible and can be mixed with non-BIMMF without inducing excess loss. Hence, BIMMF and MMF could easily be mixed in an optical channel without complicating the estimation of losses. Moreover, BIMMF may lead to higher tolerance to possible misalignments when two connectors are mated. This is an additional positive feature for 40 and 100 Gigabit applications.

In summary, a well-designed BIMMF complies with all relevant industry standards and adheres to the following:

  • BIMMF OM2, OM3 and OM4 multimode fibers are fully compliant and fully backward-compatible with all relevant industry standards.
  • BIMMF is fully backward-compatible and may be used with the existing installed base of 50/125um multimode grades including OM2, OM3 and OM4.
  • BIMMF may be spliced or connectorized to conventional 50/125um fiber types with commercially available equipment and established practices and methods, no special tools or procedures are required.
  • BIMMF not only meets all relevant macrobend standards, but sets a new level of bend performance.
Advantages of BIMMF

Bend insensitive multimode fiber is available in all laser optimized grades, OM2, OM3 and OM4, and exhibits 10 times less signal loss in tight bend scenarios and therefore protects enterprise and data center systems from unplanned downtime due to signal loss and associated significant revenue loss.

This fiber type offers extremely low bending loss at both the 850 and 1300 nm operating windows, while maintaining excellent long term fiber strength and reliability. The fiber can be installed in loops as small as 7.5 mm radius with less than 0.2 dB bending loss at 850 nm and 0.5 dB at 1300 nm.

Maximum induced bend loss performance at 850 nm Standard for multimode fibers IEC 60793-2-10 Bend Insensitive MMF (no standard currently)
Bend radius 37.5 mm 7.5 mm
Number of turns 100 2
Conventional MMF 0.5 dB
Bend Insensitive MMF 0.05 dB 0.2 dB

In addition, bend insensitive multimode fibers enable new possibilities for cable and patch panel design to further improve the benefits of using fiber. Optical cable manufacturers can now design thinner, more flexible trunk cables, making for easier cable installation and further improving airflow in conduits, patch panels and racks. Due to the ability of the fib cable to be bent tightly with significantly less signal loss, connector modules can be made smaller which in turn leads to an increased density within racks and smaller racks.

Conclusion

Bend insensitive multimode fiber has been widely employed to enhance fiber management in data centers, high performance computing and enterprise LANs. Since it is a real advance to current standard multimode fibers, BIMMF is recommended for bend and loss critical applications. What should be noticed is that BIMMF also should be handled with appropriate care as all optical glass fibers.

Fiber Optic Cable Handling Rules

Contaminated fiber optic cables can often lead to degraded network performance or even failure of the whole system. As such, to ensure that fiber optic cables can yield the best possible results of network performance, and it’s of great significance for network engineers to keep in mind how to handle fiber optic cables. Do you have any ideas? This text gives the guide to fiber optic cable handling rues.

Fiber Optic Cable Elements

Before delving into how to handle fiber optic cables, introduction to their makeup elements is required.

fiber optic cable fiver elements

Fiber optic cable generally consists of fiver elements (figure shown above): the optic core, optic cladding, a buffer material, a strength material and the outer jacket. Commonly made from doped silica (glass), the optic core is the light-carrying element at the center of the cable. Surrounding the core is the optic cladding, whose combination with the core makes the principle of total internal reflection possible. Surrounding the cladding is a buffer material used to help shield the core and cladding from damage. A strength material surrounds the buffer, preventing stretch problems when the fiber cable is being pulled. The outer jacket is added to protect against abrasion, solvents, and other contaminants.

The outer jacket on fiber optic patch cord is often color-coded to indicate the fiber types being used. For instance, multi-mode fiber (MMF) is usually in orange to distinguish from the color yellow for single-mode fiber (SMF) through which fiber optic transceivers realize relatively long distance, such as MGBLX1. This Cisco 1000BASE-LX SFP transceiver is able to achieve 10km link length over SMF.

Cisco 1000BASE-LX SFP, SMF

Fiber Optic Cable Handling Rules

Despite its outer protection mentioned above, fiber optic cable is still prone to damage. In such as case, a series of fiber cable handing rules are made to ensure that a cable is handled properly, so as to maintain the optimized performance, minimum insertion loss and safe working environments.

Rule 1: The exposed fiber end from coming in contact with all surfaces should be protected. If you contact the fiber with hard surfaces, then the end of it shall be scratched or chipped, causing the degraded performance.

Rule 2: It’s highly recommenced to lean the connector (plug) end each time it is inserted into an adapter, since since a dirty connector will contaminate an adapter.

Rule 3: If a fiber needs to be pulled, use the connector strain relief. Directly pulling on the fiber may result in the glass breaking.

Rule 4: It’s ill-advised to use your hands to clean a fiber work area. If you use your hands to wipe clean a work area, a piece of glass may get lodged into your hands. Considering the size of the glass, this glass may not be visible to the naked eye, bringing about eye damage.

Rule 5: If possible, always keep a protective cap on unplugged fiber connectors, because covering the adapters and connectors will help to avoid contamination and collection of residue. Besides, store unused protective caps in a resealable container in order to prevent the possibility of the transfer of dust to the fiber. Locate the containers near the connectors for easy access.

dust cap covers for protection

Rule 6: It’s suggestible to use fiber-cleaning materials only once. If optic grade wipes are used to clean the fiber end, they should be discarded immediately after the fiber surface has been wiped to avoid contamination.

Rule 7: The minimum bend radius of the fiber optic cable must be maintained. Surpassing the bend radius may cause the glass to fracture inside the fiber optic cable. Equally, to cause a twist of the cable is also not proposed.

Rule 8: Never look into a fiber while the system lasers are on. Eye damage may occur if you stare directly at a fiber end which is working. Always make sure that the fiber optic cables are disconnected from the laser source, prior to inspection.

After discussion, these handling rules may help you to deal with fiber optic cables and improve your network performance.

Conclusion

Proper handling procedures for fiber optic cables are needed to eliminate the possibility of being contaminated or damaged, and provide a clean environment for the network system. Fiberstore supplies many different types of fiber optic cables with high quality for various applications, like MTP cable. You can visit Fiberstore for more information about fiber optic cables.

Establishing 40G Links With OM3 and OM4

To meet the needs of Internet users, the business users in particular, who require faster speeds, greater scalability, and higher levels of network performance and reliability, data centers have experienced infrastructure transformation, from 10 Gbps to 40 Gbps and then to 100 Gbps, or even higher, never-ceasing. Actually, during this bandwidth migration, 40G provides an efficient use of hardware and a more logical upgrade path to 100G. And in establishing 40G links, fiber optic cabling, (eg OM3 and OM4) has become an integral part of the overall system design.

Background Information

The Institute of Electrical and Electronics Engineers (IEEE) 802.3ba 40/100G Ethernet Standard was ratified in June 2010 to support the fast-growing demands for bandwidth in data centers. The standard provides specific guidance for 40G/100G transmission with multi-mode fibers (MMFs) and single-mode fibers (SMFs). OM3 and OM4 are the only approved multi-mode fibers included in this standard.

Using OM3 and OM4 for 40G Links

The IEEE 802.3ba only specified OM3 for a maximum reach of 100 m in its original draft. Later, efforts have been made to win the approval to include OM4 in the standard. As a matter of fact, OM4 can achieve the greater reach of 150 m compared with OM3. In 40 GbE transmission which uses MMFs, an optic module interface is used for the simultaneous data transmission and data reception. Like JNP-QSFP-40G-LX4, this Juniper Networks proprietary 40G-LX4 transceiver listed on FS.COM realizes 100 m transmission on OM3, and 150 m transmission on OM4. Besides, JNP-QSFP-40G-LX4 can also run over SMF for 2 km link lengths.

, transmission media :SMF ,MMF

Evaluating OM3 and OM4 Performance

When evaluating the performance of the OM3 and OM4 cabling infrastructure for 40GbE transmissions, three aspects should be taken into consideration: bandwidth, channel connector insertion loss (CIL) and skew.

  • Bandwidth

In the standard, the bandwidth is ensured by meeting the effective modal bandwidth (EMB) specification. The EMB measurement techniques utilized nowadays are effective modal bandwidth calculate (EMBc) which combines the properties of both the source and fiber. The EMBc process predicts source-fiber performance by integrating the fundamental properties of light sources with the MMF’s modal structure which has been measured using a standardized differential modal delay (DMD) measurement. Within 40G links using OM3 and OM4 fibers measured by the EMBc technique, the optical infrastructure shall meet the performance criteria set forth by IEEE for bandwidth.

  • Channel Insertion Loss (CIL)

CIL is a critical performance parameter in current data center cabling deployments. It refers to the total insertion losses that happen when the signal moves along a fiber optic cable. Within a system channel, CIL impacts the ability to operate over the maximum distance at a given data rate. With total connector loss increasing, the maximum distance at that given data rate decreases. The 40/100G standard specifies the OM3 to a 100m distance with a maximum channel loss of 1.9dB, while OM4 is specified to a 150m distance with a maximum channel loss of 1.5dB.

  • Skew

Skew is classified as the difference between the arrival times of simultaneously launched light signals traveling through parallel cable lanes. When evaluating OM3 and OM4 performance for 40applications, selecting one that meets the 0.75ns skew requirement can ensure the performance.

Establishing 40G Links With OM3 and OM4

40G is deployed using eight of the twelve fibers in a MPO connector. Four of these eight fibers are used to transmit while the other four to receive. Each Tx/Rx is operating at 10G. The 40GBASE-SR4 (eg. QFX-QSFP-40G-SR4) interface is as follows: 4 x 10G on four fibers per direction.

40GBASE-SR optical lane: 4 x 10G on four fibers per direction

OM3 and OM4 for 40G connectivity provide a significant value proposition when compared to SMF, as MMF utilizes low cost 850nm transceivers for serial and parallel transmissions. OM3 and OM4 ensure today’s bandwidth needs.

Conclusion

To continue to accommodate the bandwidth needs, OM3 and OM4 are the ideal solution for 40G links in the data center. FS.COM offers broad selections of OM3 and OM4 fibers of high quality, as well as fiber optic transceivers working over OM3 and OM4, such as JNP-QSFP-40G-LX4 and QFX-QSFP-40G-SR4 mentioned above. You can visit FS.COM for more information about OM3 and OM4, MMF.

OM3 vs. OM4 Multi-mode Fiber Cables

With each passing year, the demands for higher data rates and greater bandwidth in data centers grow. An increasing number of sophisticated fiber optical products have been introduced into the telecommunication market, including fiber patch cables (single-mode fibers (SMFs) and multi-mode fibers (MMFs)), with MMFs being preferred by users. MMFs have four types, OM1, OM2, OM3 and OM4. This article mainly details the differences between OM3 and OM4, helping you clear off the confusion of these two types.

OM3 and OM4 Compatibility

The first thing to note is that OM4 is completely backwards compatible with existing OM3 systems. The connectors and termination of OM3 and OM4 are same. Besides, both OM3 and OM4 are Laser Optimised Multi-mode Fiber (LOMMF) share the same fiber core size of 50/125. So, what are the differences between them?

OM3 vs. OM4

OM4 differs from OM3 mainly in their attenuation and dispersion provided. Let’s first see the following table which shows the attenuation and dispersion of OM3 and OM4.

Type Maximum Attenuation at 850nm Minimum Fiber Bandwidth at 850nm
OM1 3.5 dB/Km 2700 megahertz*Km
OM2 3.0 dB/Km 4700 megahertz*Km
  • Attenuation Analysis

OM4 cable has lower attenuation than OM3. Attenuation refers to the reduction in power of the light signal as it is transmitted (dB). It’s caused by losses in light through the passive components, such as cables, and connectors, relatively simple to explain. The maximum attenuation at 850nm permitted by OM3 is less than 3.5 dB/Km, while the OM4 is less than 3.0 dB/Km. OM4 causes fewer losses.

  • Dispersion Analysis

Dispersion is the spreading of the signal in time due to the differing paths the light can take down the fiber. Two types of dispersion are available: chromatic and modal. Chromatic is the spreading of the signal in time resulting from the different speeds of light rays, while modal is the spreading of the signal in time resulting from the different propagation modes in the fiber. Here the focus is put on the modal dispersion. The modal dispersion determines the modal bandwidth that the fiber can operate, and this is what the difference between OM3 and OM4 lies in. The minimum fiber bandwidth at 850nm allowed by OM3 is 2700 megahertz*Km, by OM4 is 4700 megahertz*Km, meaning that OM4 can operate at higher bandwidth.

  • Other Considerations Between OM3 and OM4

OM4 is more network reliable than OM3, providing great design flexibility. What’s more, OM4 is able to reach an additional 60% links in the core-to-distribution and in the access-to-distribution channels compared to OM3 in 40G/100G Ethernet applications. In 40G Ethernet transmission using 40G QSFP, OM4 enables 150m length reach. Like Arista QSFP-40G-SR4, this 40G QSFP, when runs over OM4, enables 150m reach with MTP/MPO connector at a data rate of 40 Gbps. The image below shows what the Arista QSFP-40G-SR4 transceiver looks like.

Arista QSFP-40G-SR4

Use OM3 or OM4 for Your Network?

On the one hand, since OM3 are compatible with OM4, these two types are interchangeable when the transmission distance limitations are accessible. But on the other, the additional bandwidth and lower attenuation of OM4 make it more ideal for MMF cabling infrastructure. Whether use OM3 or OM4 for your network, it depends on the specific situations, like cost, and distance required.

Conclusion

After detailed discussion, you may have gained a better understanding of the OM3 and OM4 differences and you can quickly choose MMF types to meet your higher bandwidth system requirements. Fiberstore OM3 and OM4 provide solutions that allow more effective and bandwidth-providing network installations. Besides fiber patch cables, Fiberstore also offers copper cables for your networks, such as QSFP-H40G-CU5M. This Cisco QSFP-H40G-CU5M product listed on Fiberstore is 100% compatible with the equivalent Cisco direct attach copper cables. For more information about fiber patch cables and copper cables, you can visit Fiberstore for more information.

Fiber Optic PC Connectors: Single-channel vs. Multi-channel

Over the past 30 years, fiber optic technology has spanned its commitment constantly with the even more endeavors nowadays to meet the ever-increasing networking bandwidth for high-quality Internet applications. In these applications, fiber optic connectors, serving as mousetraps, are used to couple the source, receiver and other components to the fiber optic cable. Fiber optic connectors generally use either physical contact (PC) or expanded beam technology. This article mainly discusses PC connectors from single-channel and multi-channel aspects.

It’s necessary to figure out what PC connections are first.

What Are PC Connection?

A PC connection is accomplished by terminating the optical fiber into a precise ceramic ferrule. The tip of the ceramic ferrule is polished in a precise manner to ensure that light enters and exits at a known trajectory with little scattering or optical loss. In achieving PC connection, there are two requirements for a cleaved fiber endface for PC connection. One is that the fiber endface inclination is less than 0.6°, and the other is that there is no mist on the endface.

PC Connector Types

There are countless single-channel and multi-channel fiber optic PC connector types available for telecommunication and data-communication industries.

Single-channel Connectors

PC connectors are characteristic of directly mating and polishing fibers by utilizing tight tolerance ferrules and alignment sleeves and/or mating pins. This ceramic-ferruled technology permits reliable optical performance, with several designs becoming widely used as industry standards. Typically, these connectors are single fiber solutions with plastic shells. FC and ST connectors are becoming less popular but are still used in instrumentation. LC and SC connectors are commonly used in the telecommunication industry.

As a push-pull connector, LC connector, licensed by Lucent Technologies, provides a pull-proof design and small size perfect for high-density applications. It’s available in simplex or duplex versions, widely used in 10Gigabit, 40Gigabit and 100Gigabit applications. Like Cisco QSFP-40GE-LR4 transceiver, QSFP-40GE-LR4 listed on Fiberstore establishes 40Gigabit Ethernet (GbE) links with this duplex LC connector for 10km maximum link length over single-mode fiber (SMF).

SC connector, developed by Nippon Telegraph and Telephone (NTT), is recommended in the TIA/EIA-568-A Standard for structured cabling. It’s also available in simplex or duplex versions, typically used in Analog CATV (Cable Television) and other telecoms applications including point to point and passive optical networking.

Multi-channel Connectors

Multi-channel connectors house multiple fiber optic termini in a precision insertion. The termini can be configured as a pin/socket combination or genderless. MTP/MPO connectors belong to PC multi-channel connector.

The US CONEC MTP is a MPO compatible connector that exhibits quick and reliable connections for up to 12 fibers in a very small form factor. Just like LC connector, 40G links are likely to deploy this kind of MPO-12 connector for high performance. Take Cisco QSFP-40G-CSR4 for example, this QSFP-40G-CSR4 transceiver sets up 40G links in 850nm multi-mode fiber (MMF), with MPO-12 as its connector.

Optical Performance

Both single-channel and multi-channel PC connectors have optical performance characterized by return loss. The return loss of the connector is a measurement of how much light is reflected back at the connector interface. It’s affected by alignment, contamination and polishing. For example, if the mating faces of the two fibers are not parallel, some energy reflects back to the source. Additionally, contamination at the mating interface causes reflection and scattering of light. What’s more, a poor polish may create an end-gap separation or an end-angle.

Featuring by the tightest tolerance ceramic ferrules and alignment sleeves, coupled with the highest quality termination and polishing procedures, PC connections are able to deliver unrivaled optical performance.

Conclusion

Fiber optic connectors make quick fiber connection and efficient light transmission possible, gaining more and more popularity among their users. Fiberstore offers hundreds of fiber optic connectors, such as FC, D4, DIN, MU, the MTP/MPO ST, SC and LC, as well as their related optic modules (eg. QSFP-40GE-LR4 and QSFP-40G-CSR4 mentioned above). You can visit Fiberstore for more information about fiber optic connectors.