Category Archives: Fiber Optic Cable

Cabling Solutions for 40G Short Reach QSFP+ Transceivers

40G parallel optical transceivers use four 10G channels to transmit and four 10G channels to receive signals over a 12-fiber assembly. The middle four fibers remain unused or dark. Each fiber either transmits (Tx) or receives (Rx) 10G traffic at a single wavelength. 40gb QSFP+ is the dominant transceiver type and popular choice for 40 Gigabit Ethernet applications. Among all those QSFP+ optics, short reach QSFP+ transceivers are commonly used. This article will introduce cabling solutions for 40G short reach QSFP+ transceivers.

40G Short Reach QSFP+ Transceivers

In 2010, 40GBASE-SR4 parallel optics solution for MMF was released by IEEE standard 802.3ba as one of several 40G based solutions. Later, another solution 40GBASE-CSR4 was released. 40GBASE-CSR4 is similar to 40GBASE-SR4 but it extends the distance capabilities. These two multi-mode transceivers can also support 4x10G modes. This part will tell details about these two short reach 40G parallel optical QSFP+ transceivers.

40GBASE-SR4 QSFP+: 40GBASE-SR4 QSFP+ transceiver enables high-bandwidth 40G optical links over 12-fiber parallel fiber terminated with MPO/MTP multi-fiber female connectors. It can support link lengths of 100 meters and 150 meters over OM3 and OM4 multimode fibers respectively. 40GBASE-SR4 QSFP+ transceiver can also be used to connect with four 10GBASE-SR optical interfaces using an 8-fiber MTP to 4 duplex LC cable.

40GBASE-CSR4 QSFP+: 40GBASE-CSR4 QSFP+ transceiver can be used for native 40G optical links over 12-fiber parallel cables with MPO/MTP connectors or in a 4x10G mode with parallel to duplex fiber breakout cables for connectivity to four 10GBASE-SR interfaces. It can extend the reach of 40GBASE-SR4 interface to 300 and 400 meters over OM3 and OM4 multimode parallel fibers respectively.

Cabling Solutions for Short Reach QSFP+ Transceivers

To connect a parallel optics 40GbE short reach transceiver to another short reach 40GbE transceiver, a Type-B female MTP/MPO to female MTP/MPO cable is required. The following picture shows two 40GBASE-SR4 QSFP+ transceivers being connected with a female MTP cable. The fiber position (from 1 to 12) is reverse on the ends of the assembly. This reverse fiber positing allows signals to flow from transmission on one end of the link to reception on the other end. This type of direct connectivity is only suggested for short distances within a given row of racks/cabinets. It has less robustness (less tensile strength, less crush and impact resistance, etc.) than a distribution-style cable, which would be used for structured cabling trunks.

40G short reach connectivity solution 1

In addition to this, there are several other cabling solutions for parallel optics 40G short reach connectivity. Solution one, in the interconnect structured cabling system, MTP trunk cables will be deployed by placing them in cable trays without the fear of them being crushed.

40G short reach connectivity solution 2

Solution two, with 2×12 to 3×8 or 1×24 to 3×8 harness cable assembly, 100% fiber utilization will save the cost of fiber utilization in the structured cabling. And it also saves the cost of labor and materials. Make sure that each MTP connector is plugged into a port.

40G short reach connectivity solution 3

Solution three, this approach uses 40G channel interconnect structured with conversion devices: 2×3 or 1×3 modules. It can utilize 100% of the installed fiber as harnesses. It is easily accomplished by using Type-B non-pinned MTP to non-pinned MTP jumpers.

40G short reach connectivity solution 4

Conclusion

With the increasing demand for high-bandwidth applications such as cloud computing, server virtualization and fabric consolidation within data centers, the trend for faster data transfer rates like 40G and 100G is relentless. There are various types of 40GbE transceivers, MPO/MTP cables like MPO/MTP trunk cable and MPO/MTP harness cable, MPO/MTP cassette and other assemblies for your 40G network connectivity. You just need to make sure that you choose the right one.

What Is LSZH Fiber Optic Cable?

When choosing fiber optic jumper cables, other than selecting the right connector type on both ends of the cable, such as SC to LC fiber cable, ST ST fiber patch cable, SC/APC to LC patch cable, SC to ST fiber cable, LC to ST fiber patch cable, or SC to SC patch cord, you also need to pay much attention to the construction of fiber optic cables. Nowadays, with increasing amount of cables found in residential, commercial and industrial applications, there is a greater fuel load in the event of a fire. Wire and cable manufacturers responded by developing materials that had a high resistance to fire while maintaining performance. Low-smoke, zero-halogen (LSZH) cables proved to be a key materials group that delivered enhanced fire protection performance. How much do you know about LSZH cables? This post aims at helping you learn more about LSZH fiber optic cables.

Introduction

LSZH stands for low-smoke zero-halogen, and describes a cable jacket material that is non-halogenated and flame retardant. This type of jacket material has excellent fire safety characteristics of low smoke, low toxicity and low corrosion. When LSZH fiber optic cables (as shown below) come in contact with a flame, very little smoke is produced, making them ideal for applications where a lot of people are confined in a certain place, such as office buildings, train stations, airports, etc. A fire may be very harmful in a building, and at the same time, the smoke can cause even more damage to people who are trying to locate exits and inhalation of smoke or gases. LSZH fiber optic cables are free of halogenated materials like Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I) or Astatine (At), and those materials are reported to be capable of being transformed into toxic and corrosive matter during combustion. Low-smoke property of LSZH fiber optic cables makes them safe and helpful. More people in fires die from smoke inhalation. LSZH fiber optic cables release low smoke and zero halogenated materials in these places would be really important to the safty of people.

LSZH Fiber Optic Cables

Applications of LSZH Fiber Optic Cables

There is no doubt that the amount of fiber optic cables installed in buildings has been increasing as data communication proliferates. LSZH fiber optic cables have been common in central office telecommunication facilities, due to the large relative fuel load represented by wire and cable. Several applications of LSZH fiber optic cables are:

  • Public spaces like train stations, hospitals, schools, high buidings and commercial centers where the pretection of people and equipment from toxic and corrosive gases is critical.
  • Data centers contain large amounts of cables, and are usually enclosed spaces with cooling systems that can potentially disperse combustion byproducts through a large area. Other materials burning may also contribute greater amounts of dangerous gases which will outweigh the effect of the cables. There have been notable fires where cables burning contributed to corrosion, but in some instances, better fire response techniques could have prevented this damage.
  • Nuclear industry is another area where LSZH fiber optic cables have been and will be used in the future. Major cable manufacturers have been producing LSZH fiber optic cables for nuclear facilities since the early 1990s. The expected construction of new nuclear plants in the U.S. in coming years will almost certainly involve LSZH fiber optic cables.
Tips for Choosing LSZH Fiber Optic Cables

No two products are the same and many factors will define the suitability of the final product to its application. Research shows that 27 LSZH compounds have huge variation in physical properties. Even using material which meets the base requirements of one of the many specifications available may not result in the best material for the application. When choosing LSZH fiber optic cables, factors such as the environment and price should be considered. An environmental factor such as the temperature of the installation could reduce the flexibility of the cable. Will the application be in an open area or confined? Will other flammable material be present? Many factors need to be taken into consideration. LSZH fiber optic cables also tend to be higher in cost.

Conclusion

When selecting or designing a fiber optic cable or fiber optic jumper cable for any application, the operating enviroments where the fiber optic cable will be used, whether extreme or not, must be considered along with availability, performance, and price. And when the safety of humans and the enviroment is a consideration, along with high-performance and capability, LSZH fiber optic cables provide a good solution for you.

The Basics of Dirrect Attach Cables

Dirrect attach cable (DAC), is a cost effective and proven solution for interconnecting networking applications. It can provide inexpensive and reliable connections using either copper cables or fiber cables. What is DAC? How copper DAC and fiber DAC differ from each other? Here is what you need to know about DACs.

DAC Definition

A direct attach cable is a fixed assembly that is purchased at a given length, with the connector modules permanently terminated to each end of the cable to connect switches to routers or servers. DACs are much cheaper than the regular optics, since the “transceivers” on both ends of DACs are not real optics and their components are without optical lasers. They are preferable choice for their low cost, low power consumption and high performances. DAC are made of the two kinds of cable materials: copper and optical fiber. They are respectively called direct attach copper cable and active optical cable.

DAC Assemblies—Copper

Direct attach copper cable is interchangeable and hot swappable with fiber optic modules. It is designed in either active or passive versions. It supports such multiple protocols as Gigabit & 10G Ethernet, 8G FC, FCoE and InfiniBand. Direct attach copper cable is a cost effective solution over optical transceivers and and cables for short reach applications. It can support higher data rates than traditional copper interfaces—from 4Gbps to 10Gbps per channel. The defect of direct attach copper cable is that it is heavy and bulky, making it difficult to be managed. Furthermore, due to the nature of electrical signals, direct attach copper cable is vulnerable to the effects of electromagnetic interference (EMI), such as undesirable responses, degradation, or complete system failure. Fiberstore offers various QSFP+ direct attach copper cables with different lengths for your 40G applications. For example, lengths of Juniper EX-QSFP-40GE-DAC-50CM, QFX-QSFP-DAC-1M and QFX-QSFP-DAC-3M compatible QSFP+ to QSFP+ passive copper cables are respectively 0.5m, 1m, and 3m.

0.5m Juniper EX-QSFP-40GE-DAC-50CM Compatible QSFP+ to QSFP+ Passive Copper Cable

DAC Assemblies—Fiber

Active optical cable (AOC) is an alternative to optical transceivers, eliminating the separable interface between transceiver module and optical cable. It meets Small Form-factor (SFF) standards. Compaired to direct attach copper cable, AOC weighs less and can support longer transmission distance. It is immune to electromagnetic energy since the optical fiber is dielectric (not able to conduct electric current). What’s more, it is an alternative to optical transceivers and it can eliminate the separable interface between transceiver module and optical cable. AOC has no EMI. However, it costs more than copper cable.

Active_Optical_Cables

Applications of DAC

Direct attach cables are widely applied in storage area network, data center, and high-performance computing connectivity. They suppoet high speed I/O applications in storage, networking and telecom markets. And they can also be sused in witches, servers, routers, network interface cards (NICs), and Host Bus Adapters (HBAs). There are many different kinds of DACs, they all have their specific applicayions. For example, 40G AOC is commonly used for short-range multi-lane data communication and interconnect applications.

Conclusion

Fiberstore offers a variety of high speed interconnect DAC assemblies including 10G SFP+ cables, 40G QSFP+ cables, and 120G CXP cables to satisfy the demands from 10G to 100G interconnection. Direct attach cables provided by Fiberstore can be customized to meet different requirements. And we also offer all kinds of high quality QSFP+ modules branded by many famous companies, like Brocade QSFP+, Dell QSFP+, Juniper QSFP+, Finisar QSFP+, Intel QSFP+, etc. You can buy from us with confidence.

When to Use Single-mode Fiber Optic Cable?

MMKnowing when to use a single-mode fiber optic cable is very necessary for people who want to design a reliable and sustainable optical network. There are advantages of using single-mode fiber optic cable. Here is what you need to consider if you’re going to be working with single-mode fiber optic cable.

The Advantages of Using Single-mode Fiber Optic Cable

Single-mode fiber optic cable typically has a smaller core diameter than multi-mode fiber optic cable. The small core of a single-mode fiber allows only one mode of light to propagate, so there is no possibility of distortion due to overlapping light pulses. Because of this, the number of light reflections created as the light passes through the core decreases. The following picture shows how light is transmitted in a single-mode fiber.

Single-mode Fiber

Generally, single-mode fiber optic cable provides less signal attenuation, higher transmissions speeds, and up to 50 times greater transmission distance than multi-mode cable. Single-mode fiber optic cable can transmit data at terabits per second over 100km without requiring re-amplification of the signal. The small core of single-mode fiber optic cable and single light wave virtually eliminate any distortion that could result from overlapping light pulses, providing the least signal attenuation and the highest transmission speeds of any fiber cable type.

When to Use Single-Mode Fiber Optic Cable?

When the transmission distance is greater than 3000 feet or 914.4 meters, then multiple paths of light can cause signal distortion. This can result in an unclear and incomplete data transmission. At this time, single-mode fiber optic cable may be the solution. Single-mode fiber optic cable is used in many applications where data is sent at multi-frequency where only one cable is needed (single-mode on one single fiber). Single-mode fiber optic cable is often used for telecommunication networks and high speed multi-channel video, data and voice services in metropolitan and access networks. They are applied in these areas, CATV/VIDEO, PON, WDM/DWDM, FTTH, data centers, ATM, SONET and WDM. The following picture shows a single-mode fiber optic cable.

Single-mode Fiber Optic Cable

Knowing when to use single-mode fiber optic cable is half the battle of creating a winning design. Using it incorrectly can result in signal distortion or another undesirable occurrence. It’s always best to make the proper decision for your design or company to ensure that you will have optimal performance. It is not always easy to know when to use single-mode fiber optic cable, but it can be determined by simply knowing how far the signal needs to be transmitted and the environment that the cable will be in during transmission.

Fiberstore provides a wide range of optical fiber cables 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. They supply fiber optic cables with custom length and of famous brands, such as Corning.

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