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.

LC Connector Family

The LC connector developed by Lucent Technologies and shown in Fig.3.10 is a more evolutionary approach to achieving the goals of a SFF connector. The LC connector utilizes the traditional components of a SC duplex connector having independent ceramic ferrules and housings, with the overall size scaled down by one-half. The LC family of connectors includes a stand-alone simplex design; a “behind the wall” (BTW) connector and the duplex connector available in both single-mode and multimode tolerances are all designed using the RJ-style latch.

The outward appearance and physical size of the LC connector varies slightly depending on the application and vendor preference. Although all the connectors in the LC family have similar latch styles modeled after the copper RJ latch, the simplex version of the connector has a slightly longer body than either the duplex or BTW version, and the latch has an additional latch actuator arm that is designed to assist in plugging as well to prevent snagging in the field. The BTW connector is the smallest of the LC family and is designed as a field-or board-mounatable connector using 900-um buffered fiber and in some cases has slightly extended latch for extraction purposes. The duplex version of this connector has modified body to accept the duplexing clip that joins the two connector bodies toghther and actuates the two latches as one. Finally, even the duplex clip itself has variations depending on the vendor. In some cases the duplex clip us a solid one-piece design and must be placed on the cable prior to connectorization, while other design and must be placed on the cable prior to connectorization, while other designs have slots built into each side to allow the clip to be installed after connectorzation. In coclusion, all LC connectors are not created equal, and depending on style and manufacturer’s preference, there may be attributes that make one connector more suitable for a specific application then another.

The LC duplex connector incorporates two round ceramic ferrules with outer diameters of 1.25mm and a duplex pitch of 6.25mm. These ferrules are aligned through the traditional couplers and bores using precision ceramic split or solid sleeves. In an attempt to improve the optical performance to better than 0.10 db at these interfaces, most of the ferrule and backbane assemblies are designed to allow the cable manufacturer to tune them. Tuning of the LC connector simply consists of roating the ferrule to one of four available positions dictated by the backbone design. The concept is basically to align the concentricity offset of each ferrule to a single quadrant at 12.00; in effect, if all the cores are slightly offset in the same direction, the probalility of a core-to-core alignment is increased and optimum performance can be achieved. Although this concept has its merits, it is yet another costly step in the manufacturing process, and in the case where a tuned connector is mated with an untuned connector, the increase in performance may not be realized.

Typically, the LC duplex connectors are terminated onto a new reduced-size zipcord referred to as mini-zip. However, as the product matures and the applications expand, it may be found on a number of different cordages. The mini-zip cord is one of the smallest in the industry with an outer diameter of 1.6mm compared with the standard zipcord for an SC style product of 3.0 mm. Although this cable has passed industry standard testing, the cable manufacturers have raised some issues concering the ability of the 900-um fibers to move freely inside a 1.6-mm jacket and others involving the overall crimped pull strengths. For these reasons, some end users and calbe manufactures are opting for a larger 2.0-mm, 2.4-mm, or even the standard 3.0-mm zipcord. In application wher the fiber is either protected within a wall outlet or cabinet, the BTW connector is used and terminated directly onto the 900-um buffers with no jacket protection.

The factory termination of the LC cable assemblies is very similar to order ceramic-based ferrules using the standard pot and polish processes with a few minor differences. The one-piece design of the connector minimizes production handling and helps to increase process yields when compared with other SFF and standard connector types. Because of the smaller diameter ferrule, the polishing times for an LC ferrule may be slightly lower than the standard 2.5-mm connectors, but the real production advantage is realized in teh increase number of connectors that can be polished at one time in a mass polisher. For the reasons mentioned above and because the process is familiar to most manufacturers, the LC connector may be considered one of the eaisest SFF connectors to factory terminate.

Field termination of the LC connector has typically been accomplished through the standard pot and polish techiques using the BTW connector. However, a pre-polished, crimp and cleave connector is also available. The LCQuick Light field-mountable BTW style connector made by Lucent Technologies is a one-piece design with a factory polished ferrule and an internal cleaved fiber stub. Unlike other pre-polished SFF connectors previously discussed, the LCQuick light secures the inserted field cleaved fiber to a factory polished stub by crimping or collapsing the metallic entry tube onto the buffered portion. This is accomplished by using a special crimp tool that is designed not to damage the fibers. However, light is designed specifically for use in protected environments such as cabinets and wall outlets and has no provision for outer jacket or Kevlar protection.

LC connections allow higher density applications based on its smaller diameter. The LC connection, commonly referred to as Lucent Connection, Little Connector or Local Connector, is commonly used today for uplink modules and other devices. This connector is a “snap” type, has a ferrule diameter of 1.25mm and defined by IEC 61754-20. We offer LC fiber cables and lc lc cable, including single mode 9/125 and multimode 50/125, multimode 62.5/125, LC-LC, LC-SC, LC-ST, LC-MU, LC-MTRJ, LC-MPO, LC-MTP, LC-FC, OM1, OM2, OM3. Other types also available for custom design. Excellent quality and fast delivery.

The LC fiber patch cable cable is with a small form factor (SFF) connector and is ideal for high density applications. The LC fiber patch connector has a zirconia ceramic ferrule measuring 1.25mm O.D. with either a PC or APC end face, and provides optimum insertion and return loss. The LC fiber patch cable connector is used on small diameter mini-cordage (1.6mm/2.0mm) as well as 3.0mm cable. LC fiber cable connectors are available in cable assembled or one piece connectors. The LC fiber optic assemblies family is Telcordia, ANSI/EIA/TIA and IEC compliant.

Optical Cables Options In SANs

Today, that high-speed network usually consists of fiber optic cable and switches that use light waves to transmit data with a connection protocol known as Fibre Channel. (A protocol is a set of rules used by the computer devices to define a common communication language.) More and more, regular Internet provider (IP)-based networks, such as the Internet, are being used as the network part of a SAN.

The act of using a network to create a shared pool of storage devices is what makes a SAN different. The network is used to move data among the various storage devices, allows sharing data between different network servers, and provides a fast connection medium for data backup and restoration and data archiving and retrieval. Devices in a SAN are usually bunched closely together in a single room, but the network allows the devices to be connected over long distances. The ability to spread everything out over long distances makes a SAN very useful to large companies with many offices.

Fiber optic cable is one of the simplest parts of a SAN and one of the most time-consuming to troubleshoot when something goes wrong. It’s better to make sure nothing goes wrong by taking care in the installation and handling of your SAN cabling.

This chapter provides reference material for readers who may be less familiar with either Fiber Channel or IP/Ethernet technology. The following we will introduce the optical cables options in SANs. Next, we will mention LC-LC cables, SC-LC cables, SMF cables.

LC-LC Cables

LC connector are used to attach fiber optic cable to SFPs and patch panels. An LC to LC fiber cable has this connector on each end. It could be used to connect two routers together, to connect a router to a 1Gbit or 2Gbit Fiber Channel device or switch, to a patch panel, or to many Gigabit Ethernet devices. These cables can be purchased in either MMF or SMF versions.

SC-LC Cables

SC connector are used to attach fiber optic cable to GBICs and patch panels. An SC to LC fiber cable has this connector on one end and an LC connector on the other end. It could be used to connect a router to an older Fiber Channel node or switch, to a patch panel, or to many Gigabit Ethernet devices. Some 2Gbit FC devices use and therefor SC connectors as well, and the router would require this cable to connect to them. These cables can be purchased in either MMF or SMF verisons.

MMF Cables

Multi-Mode Fiber is used for short distances. It is less expensive than SMF, and is the most common cables type for use inside a datacenter or campus. These cables use a larger diameter (50/125um or 62.5/125um.) fiber core on the inside of the cladding. (Cladding is the sheath around the outside of the fiber.) Most often these cables are used with SWL GBICs and SFPs. Be sure to check that the transeiver is designed to work with the cable diameter (50 or 62.5) since there are two formats. Brocade switches all work equally well with either format, so it should work as long as the transceiver is supported by Brocade and matched to the cable. Usually, MMF cables are orange, but they can ordered in non-standard colors so this is not a totally reliable way to distinguish them from SMF cables. Look for writing on the cable cladding as well.

SMF Cables

Single-Mode Fiber can be used for short distances, but due to its greater cost it is almost exclusively use for much longer distance links in combination with LWL, ELWL or WDM solutions. Generall speaking, these soloutions are desinged for SMF cables with media designed for MMF can cause problems. SMF cables use a much smaller diameter fiber core inside the cladding: 9/12um. They are usually colored yellow, but like MMF cables they can be ordered in other colors.

I hope this post was helpful to you when you are choosing optic cable in SANs. If you are interested in requesting a optical cable, please go to the Fiberstore online website.

Understanding Fiber Optic Cable Specifications

Most cable configurations come with various sizes and types of fibers. For example many fibers have a buffer coating of 250 or 950 um diameter. This coating allows fibers of 8/125, 50/125, 62.5/125, or 100/140 um to be used. Each of these fibers can further be offered with various attenuations and bandwidths to satisfy the needs of a particular application. In addition, a cable using a loose-tube buffer can hold one or several fibers. None of these factors significantly influences cable construction. The same construction can accommodate all these differences easily.

As fiber optic technology became widespread, serious dabate evolved over which multimode fiber was best suited to different applications. For example, 62.5/125 and 100/140 um fibers were all proposed for premises wiring and local area networks. The debate centered on the technical and costs merits of each fiber: attenuation, bandwidth, NA, ease and cost of coupling light into the fiber, and so forth.

Multimode fiber is usually 50/125 and 62.5/125 in construction. The “winner” of these debates was the 62.5/125 um fiber, which is the specified or preferred fiber in nearly all applications involving premises wiring, LANs, computer interconnections, and similar uses. 50/125 fiber is making a “comeback” because of its higher bandwidth. Common type of 50/125 fiber optic cable has OM4 fiber optic cable, OM3 fiber optic cable, OM1 and OM2 fiber optic cable. Both OM1 and OM2 multimode cables use the orange color jacket (standard practice for commonly used indoor multimode), OM3 use a special color, which is called Aqua.

Single-mode fibers are still the preferred choice for long-distance, high-speed applications, while both 50/125 and 100/140 um are used in many applications. Here we recommend you singlemode simplex fiber optic cable from Fiberstore, they are designed for production termination where consistency and uniformity are vital for fast and efficient operation.

Fiber optic cables are typically offered with standard-grade and premium-grade fibers. Many application standards specify performace that is met by standard-grade cables. In most cases, the cable performance is a minimum, the cable may exceed the stated performance for a requirement such as bandwidth. For example, most standards call for a 62.5 um cable to have a minimum bandwidth of 160 MHz at 850 nm and 300 MHz at 1300 nm. The standard for FDDI networks call for a 500-MHz bandwidth at 1300 nm. It is possible to buy cable with a bandwidth of 200 MHz at 850 mn and 600 MHz at 1300 nm. Similarly, 50/125 um is available with a standard bandwidth of 500 MHz or an extended bandwidth of 1000 MHz (at both 850 and 1300 nm). The point is that it is possible to buy cabled fiber at different levels of performance for the same type of fiber.

As the best OEM fiber optic cable manufacturer, we provides a fantastic selection of bulk fiber optic cable with detailed specifications displayed for your convenient selecting. Per foot price of each fiber cable is flexible depending on the quantities of your order, making your cost of large order unexpected lower. Buy fiber optic cable from fiberstore, you can custom the cable plant to best fit your needs.

Number Of Individual Optical Fibers

Fiber optic cables come in many configurations. The fiber strands can be either single mode or multimode, step index or graded index, and the cable jacketing can be either tight buffered or loose-tube buffered. The fiber strands have a variety of core diameters. Most often, the fiber strands are glass, but plastic fiber optic cable exists as well. Finally, the cables can be strictly for outdoor use, strictly for indoor use,or a “universal” type that works both inddors and out. These cables also have various fiber ratings. This article mainly introduce the number of optical fibers.

The difference between fiber optic cables is the number of individual optical fibers with them. The number depends on the intende use of the cable and can increase the cables’s size, cost, and capacity.

Because the focus of this book is network cabling and the majority of fiber optic cables you will encounter for networking are tight buffered, we will limit our discussions here to tight-buffered cables. Thes cables can be divided into three categories based on the number of optical fibers:

  • Simplex cables
  • Duplex cables
  • Multifiber cables

A simplex fiber optic cable has only one tight-buffered optical fiber inside the cable jacket. Because simplex cables have only one fiber inside them, only aramid yarn is used for strength and flexibility; the crimped directly to a mechanical connector. Simplex fiber optic cables are typically categorized as interconnect cables and are used to make interconnections in front of the patch panel.

Duplex cables, in contrast, have two tight-buffered optical fibers inside a single jacket (as shown in Figure 8.12). The most popular use for duplex fiber optic cables is as a fiber optic LAN backbone cable, because all LAN connections need a transmission fiber and a reception fiber. Duplex cables have both inside a single cable, and running a single cable is of course easier than running two.

duplex cable

One type of fiber optic cable is called a duplex cable but technically is not one. This cable is known as zip cord. Zip cord is really two simplex cables bonded together into a single flat optical fiber cable. It’s called a duplex because there are two optical fibers, but it’s not really duplex because the fibers aren’t covered by a common jacket. Zip cord is used primarily as a duplex patch cable. It is used instead of true duplex cable because it is cheaper to make and to use. Most importanly, however, it allows each simplex cable to be connectorized and crimped directly to a mechanical connector for both strength and durability. Figure 8.13 shows a zip cord OM4 fiber optic cable.

OM4 Zip cord

Finally, multifiber cables contain more than two optical fibers in one jacket. Multifer cables have anywhere from three to several hundred optical fibes in them. More often than not, however, the number of fibers in a multifiber cable will be a multiple of two, as discussed earlier, LAN applications need a send and a receive optical fiber for each connection. Six, twelve, and twenty-four fiber cables are the most commonly used for backbone applications. These cables are typically used for making connections behind the patch-panel (aslo known as “behind the shelf” connections).

FS.COM specialize in fiber optic cables with expert advice, large in-stock inventory of bulk fiber optic cable and a high level of customer service. Bulk fiber optic cable are available in simplex, duplex, breakout, distribution and indoor, outdoor types. Other types also available for custom design. Excellent quality and fast delivery.

The Advantages and Disadvantages of Multimode Fiber and Single Mode Fiber Cable

Recently, fiber optic cable becomes more popular in telecommunication because of its great bandwidth, fast speed, long distance transmission and low cost. Single mode fiber and multimode fiber optic cables are important in many networks to transmit optical signals. Though they have the same working principle and functions, each of them has their own advantages and disadvantages.

Multimode and Single Mode Fiber Cable Overview

People who have work experiences with optical networks may be familiar with fiber optic cables. And they may know the basic structure and differences between multimode and single mode fiber optic cable. Here is a simple table showing the basic knowledge of them.

single mode fiber and multimode fiber cable

From the table we can see, multimode fiber cable has a larger core diameter. And it has multiple transmission modes, but they are only suitable for short distance connections. While single mode fiber has a small core diameter, through which only one mode will propagate typically 1310 or 1550nm. Because of that, these cables are often deployed in long distance transmission due to its less dispersion. Following is a direct-viewing picture shows the diameter differences between single mode fiber and multimode fiber cables.

single mode fiber cable vs multimode optical fiber

Advantages and Disadvantages of Single Mode fiber Cable

As has mentioned above, single mode fiber optic cable is more suitable for long runs applications when compared with multimode fiber cable. Except for this, single mode fiber cable also has other three advantages.

  • Increase bandwidth capacity.
  • Limited Data Dispersion & External Interference. The single input mode allows SMF to limit light scattering, which in turn reduce light waste and increase data transmission data.
  • Fast Transmission Speed. Single mode fiber cable can support data transmission speed up to 10Gbps.

Each coin has two sides. Single mode fiber cable also has disadvantages. The most one is the cost. Although it has better performance in long runs transmission than multimode fiber cable, single mode fiber cables often cost more.

Advantages and Disadvantages of Multimode fiber Optic Cable

With a larger fiber core and good alignment tolerances, multimode fiber cable and components are less expensive and are easier to work with other optical components like fiber connector and fiber adapter, when compared with single mode fiber cable. In addition, multimode fiber cable also provides high speed and high bandwidth over short distances. And they allows several mode optical signals transmitted at the same time.

However, multimode fiber cable has high dispersion and attenuation rate, the quality of optical signals is reduced as the transmission distance is getting longer. Therefore, multimode fiber cable is often used in data and audio/video applications in LANs.

Owning to their own characteristics, single-mode fiber cable and multimode fiber cable have different application areas. Based on the transmission distance and deployment budget, if the transmission distance is less than 10 miles, the multimode fiber cable is better, for it needs less expensive optical transceiver and other components. And if the distance is over 10 miles, single mode fiber will be needed.

Related Article: Single Mode vs Multimode Fiber: What’s the Difference?

How Much Do You Know About the Fiber Optic Cable?

What is fiber optic cable?

A fiber optic cable is a network cable that contains strands of glass fibers inside an insulated casing. These fiber optic cables are designed for long distance and very high bandwidth network communications. The optical fiber elements are typically individually coated with plastic layers and contained in a protective tube suitable for the environment where the cable will be deployed. Different types of cable are used for different applications, for example long distance telecommunication, or providing a high speed data connection between different parts of a building.

Fiber optic cables carry communication signals using pulses of light. While expensive, these cables are increasingly being used instead of traditional copper cables, because fiber offers more capacity and is less susceptible to electrical interference. So called Fiber To The Home (FTTH) installations are becoming more common as a way to bring ultra high speed Internet service to residences.

What are the color codes for fiber optic cable?

The fibers in optical fiber cables are numbered according to their color code, which simplifies connecting hardware installation and connector termination as well as further administration and testing of the cabling system.

fiber optic color code

The fibers are numbered in accordance with the individual standard color code given in figure 1. 250- and 900-micron buffer coatings are subject to color-coding. In modular design multifiber cables, the same color coding is applied with respect to modules.

In loose tube cables, with over 12 fibers in one tube, fibers can be combined to form a single unit fixed by colored threads.

In some cases to facilitate pair grouping the fibers are painted the same colors with collar marks every 2-3 cm (0.8 – 1.2 in) on the second fiber of the pair.

Colored outer jackets or print may be used on Premises Distribution Cable, Premises Interconnect Cable or Interconnect Cord, or Premises Breakout Cable to identify the classification and fiber sizes of the fiber.

When colored jackets are used to identify the type of fiber in cable containing only one fiber type, the colors shall be as indicated in Table 1. Other colors may be used providing that the print on the outer jacket identifies fiber classifications in accordance with subclause 4.3.3. Such colors should be as agreed upon between manufacturer and user.

Unless otherwise specified, the outer jacket of premises cable containing more than one fiber type shall use a printed legend to identify the quantities and types of fibers within the cable. Table 3 shows the preferred nomenclature for the various fiber types, for example “12 Fiber 8 x 50/125, 4 x 62.5/125.”

When the print on the outer jacket of premises cable is used to identify the types and classifications of the fiber, the nomenclature of Table 3 is preferred for the various fiber types. Distinctive print characters for other fiber types may be considered for addition to Table 1 at some future date.

fiber optic cable color code

Notes:

1. Natural jackets with colored tracers may be used instead of solid-color jackets.

2. Because of the limited number of applications for these fibers, print nomenclature are to be agreed upon between manufacturer and end-user.

3. Other colors may be used providing that the print on the outer jacket identifies fiber classifications.

4. For some premises cable functional types (e.g, plenum cables), colored jacketing material may not be available. Distinctive jacket colors for other fiber types may be considered for addition at some future date.

How does a fiber optic cable work?

To understand how a fiber optic cable works, imagine an immensely long drinking straw or flexible plastic pipe. For example, imagine a pipe that is several miles long. Now imagine that the inside surface of the pipe has been coated with a perfect mirror. Now imagine that you are looking into one end of the pipe. Several miles away at the other end a friend turns on a flashlight and shines it into the pipe. Because the interior of the pipe is a perfect mirror, the flashlight’s light will reflect off the sides of the pipe (even though the pipe may curve and twist) and you will see it at the other end. If your friends were to turn the flashlight on and off in a morse code fashion, your friend could communicate with you through the pipe. That is the essence of a fiber optic cable.

Transmitter

A transmitter is a device found at the beginning of a fiber optic cable network. The transmitter takes information and turns it into a pulsing light wave that can be sent along a fiber optic cable. A lens is then used to send the light into a fiber optic cable. The light will travel along the fiber optic cables more quickly and with less signal degradation than occurs when sending data along traditional coper wires.

Fiber Optic Cable

The core of a fiber optic cable is made of a very clear glass tube that transmits light. This glass core is surrounded by a coating called cladding. Light will travel down the fiber optic tube in a straight line. Unfortunately, not all fiber optical cables can be laid along a straight path, so the cladding surrounding the cable is mirrored. The light bounces off of the mirrors on the cladding and is directed back into the fiber optic core to continue its journey along the cable.

Optical Regenerator

Sometimes a light signal must travel through a fiber optic cable over a very long distance. Although signal degradation is minimal in a fiber optic cable, some degradation does occur. When a cable covers a long distance, optical regenerators are placed at certain intervals along the cable. Optical regenerators are fibers that have been treated with a laser. The molecules in the fiber allow the signal traveling through the fiber optic cable to take on laser properties themselves, which strengthens the light signal. Optical regenerators essentially strengthen the light signal that is traveling through a fiber optic cable.

Optical Receiver

At the end of the fiber otic network there is an optical receiver. This receiver is essentially performs the opposite function of the transmitter found at the beginning of the system. Optical receivers receive the light signal from the fiber optic cable and turn it back into information that a computer or television know how to understand and use. It then sends the decoded signal to the computer or television.

Types of loose tube fiber optic cables

FiberStore have many types of loose tube fiber optic cables, such as All -Dielectric Loose Tube Cables, Gel-Filled Loose Tube Cables, Double-Jacket Loose Tube Cables, Central Loose Tube Cables.

The Current Situation and Future of The Optical Devices and Optical Module

Optical fiber communication media Gazettabyte LightCounting recently had an interview with a market research company, the CEO of Vladimir Kozlov, understand their views on the current situation and the optical device module industry and the future.

Q: How do you summarize the current status of optical components and modules industry?

VK: Overall, the telecom market is relatively flat, or even in hibernation; while the data communications market performance is beyond our expectations. In the filed of data communication, not just 40Gig and 100Gig, even 10Gig of faster growth than expected. 10GbE module shipments this year will exceed 1GbE.

The main reason is the growing demand for data center connectivity -“Spine and Leaf) switch architectures require more connections between the rack and aggregation switch. I suspect that demand has not only come from the data center, even enterprises to adopt 10GbE i would not be surprised, because 10GbE is not expensive. As a service provider Ethernet access lines, and use it for move backhaul.

Q: Could you explain the cause of the telecom market are flat?

VK: Part of the reason of the telecom market “dormant” is the rapid decline in SONET/SDH market. Decline in SONET/SDH market is to be expected, but the last two years, shrinking speed of the market continues to accelerate. First 40G OC-768 fell, and then is 10Gig sales decline. 10 gbe is SFP + encapsulation, and OC – 192 SONET/SDH is still XFP package.

Satability and growth in the wireless backhaul market DWDM module market to make up for the decline in SONET/SDH market. Also this year, FTTX transceivers and BOSA shipments fell sharply, while being largely replaced BOSA transceiver.

Q: LightCounting emphasized the strong growth in 2013 100G DWDM, and this year the line card port shipments reached 40,000. However, LightCounting analysis of 100Gig deployments are still relatively careful, this is why?

VK: From 10Gig and 40Gig deployment of historical experience, we must be careful.

To 10Gig deployment, for example, in optical communications bubble before (1999-2000), people are expected to 10Gig will have a huge demand. In 1999 and 2000, far more than the actual flow rate required to support 10Gig be installed until 2005, after the market are relatively flat. In 2006 and 2007, 10Gig market will rise again, after that 40Gig port shipments reached 20,000 in 2008. But with the outbreak of the economic crisis later, the development of the market in 2009 40Gig interruption until 2010 40Gig demand began to grow, this year is expected to reach 70,000 port shipments.

40Gig is greater than 100Gig, but so far 40Gig in MAN has almost none. Now 100Gig again upset 40Gig market.

I’m trying to come up intriguing problem is that the current bottleneck of MAN in where? May be some cities need to deploy 100Gig, but the metropolitan area has deployed a large number of fibers. If the fiber cost is not an issue, then why the need 100Gig? Operators will use fiber and 10Gig make more money.

CenturyLink has recently announced its first customer purchase 100Gig connection-Digital Globe, which specializes in high-definition mapping technology focus – the customer will use 100Gig connection between its data centers to transfer large amounts of data. Although the number of data centers worldwide is increasing, but this is just a special case. Needless to say, once 1GbE become ubiquitous broadband access lines, MAN or metro – access networks will need 100Gig, 10Gig will also be widely used in the access convergence layer. This situation has started to occur.

Therefore, 100Gig in MAN will happen, there is only a problem when. After two or three years, or 10-15 years also? Make predictions, people often make mistakes on the timeline, because they overestimated the impact of new technologies in the short term, while underestimating the impact of new technologies in the long term.

Q: The market development of LightCounting what about 2014?

VK: A major focus is to look at how the cable service provider’s revenue, in particular, how the additional revenue from FTTx services.

AT & T and Verizon Q313 results are good. With the growth of revenue from FTTx cable, which will encourage operators to invest more to support these services. I was thinking, this is not the beginning of a long-term trend of the future.

Today, AT & T and Verizon customers are willing to pay a little more for faster connections, but to jump to the next level, you also need to develop new applications for end users. Some applications have emerged, but we do not know what specifically. I suspect that Google offers 1Gbps FTTH services in the United States for several communities is one of the reasons end-user needs through research to discover these new applications.

A related topic is whether the deployment of broadband services to improve economic growth and how to improve. We have high expectations for this, but I want to see in 2014 in this area if there is more data.