Which Is the Best 10G Network Solution: 10GBASE-T or SFP+?

The past few years have witnessed the extensive adoption of 10Gbps connectivity at data center equipment. The expansion 10 Gigabit Ethernet is supposed to satisfy the increasing demand for higher-performance servers, storage and interconnects. Since 10G network generally provides both optical and copper options, here comes the challenge for every IT technician: how to select the appropriate 10G connectivity solution? And could it be able to support data center deployments and trends concerning current situation and the future? In this article, we will compare 10GBASE-T and SFP+ options, and try to offer some help.

Options for 10G Network Connectivity

Two of the most widely used methods of connecting servers and storage to switches of 10Gb Ethernet network are using 10GBASE-T and SFP+. Many IT technicians are now evaluating the 10GBase-T technology, with the fact that 10GBase-T is easier to deploy and cheaper than the alternative SFP+ technologies.

10GBASE-T Option

The wide usage of 10GBASE-T being implemented takes the form of embedded RJ45 port. The advantage of which is that it allows users to capitalize on their existing Cat6a UTP structured cabling ecosystem. But the solution with embedded 10GBASE-T RJ45 ports lacks flexibility. And those unused ports still consume power thus resulting in higher operating cost.

SFP+ Option

For 10Gb/s data rates, SFP+ direct attach cables (DACs) are implemented as a fixed length of Twinax cable with SFP+ plugs integrated at both ends. Passive versions can be used for connections up to 7m and active versions for connectivity up to 15m. A DAC is a low power, low latency connection with flexibility. But it can be difficult to install through typical cable management. The difficulty increases with DAC length. Moreover, a DAC can be an expensive alternative as it does not take the advantage of the installed Cat6a structured cabling.

Comparison Between 10GBASE-T and SFP+

Comparing Power and Latency

Advancements allow switch manufacturers to significantly lower power consumption on 10GBASE-T server and switch ports. A range of 10GBASE-T switches with 1.5 to 4 W per port are available on the market depending on distance.

However, the SFP+ interface that has been widely deployed for 10 gigabit ToR switches continues to use less power, typically less than 1 W per port. It also offers better latency—typically about 0.3 microseconds per link. 10GBASE-T latency is about 2.6 microseconds per link due to more complex encoding schemes within the equipment.

Features lower power consumption and lower latency, SFP+ is well suited for large high-speed supercomputing applications where latency is a critical factor and where high port counts can add up to significant power savings.

Comparing Cost and Interoperability

The cost of 10GBASE-T technology has been driven down in the past years. And with 10GBASE-T rapidly becoming the de factor LOM technology, the use of SFP+ means an additional cost of adapters for the servers. In comparing one of the latest SFP+ and 10GBASE-T ToR switches, the cost of 10GBASE-T ranges from 20% to 40% less.

10GBASE-T also has the advantage of being an interoperable, standards-based technology that uses the familiar RJ45 connector. It provides backwards compatibility with legacy networks. While SFP+ solutions are limited with little or no backwards compatibility.

10GBASE-T can offer more design flexibility using a structured cabling approach for longer distances up to 100 meters, as well as shorter ToR switch-server connections using category 6A patch cords. A structured cabling approach means that Category 6A cables can be field terminated on patch panels to any length for clean, slack-free cable management. However, SFP+ DAC offers less than 10m distance, and they are factory terminated and must be purchased in pre-determined lengths.

10GBase-T advantages

• Lower deployment cost and easier to install and migrate
• Much longer reach, 100 meter vs. 8.5 meter
• Familiar RJ45 connectors and Cat 5/6/7 cables
• Use of patch panels and structured wiring
• Backward compatibility to 1 gigabit Ethernet or 100 megabit Ethernet

SFP+ DAC advantages:

• Significantly lower overall cost, when you include switch, NIC and cable
• Lower latency – 300 us per hop vs. 2.6 us per hop
• Lower power and lower heat
• Freely intermix fiber and DAC to meet distance requirements

Conclusion

When you have to choose between SFP+ and 10GBASE-T, the decision should be based on your need. SFP+ DAC match better for the requirements and emerging trends of today’s data center. 10GBase-T will be a better choice for wiring closet since the demand for bandwidth becomes more acute. For equipment that power consumption and lower latency are critical, SFP+ might more suitable. But If cost, flexibility and scalability are more vital, you may consider 10GBASE-T. Both of them should find an important place in the future of network design and best practices.

Originally published: http://www.fiber-optic-solutions.com/best-10g-solution-10gbase-t-sfp.html

Use PDU to Enhance Data Center Energy Efficiency

The tendency to increase server and rack power densities has inevitably led to cable and power management complexities. And this is a huge problem that many data center managers may encounter. Thus, to implement a power distribution unit (PDU) serves as a vital primary step in simplifying cable management and powering your high-density network environment. It means that when you demand for reliable, flexible and easy-to-install power distribution to maximum network uptime and to save energy costs. PDU can be an optimum solution for you.

What Is Power Distribution Unit (PDU)

A power distribution unit (PDU) is a type of electrical component that distributes and manages electricity supply to computers, servers and networking devices within a data center. It is known that in a network environment, servers, storage and networking equipment can only operate when there is power to drive them. Thus, a PDU provides a central unit to control and distribute electricity, and supply to the rack via multiple outlets to the rack’s servers and critical IT equipment.

Capable of managing and distribute large amount of electricity, PDU is usually directly installed in the rack. Moreover, it can also be connected and accessed over the network or in the remote distance, and provide statistics and data on the power usage effectiveness (PUE).

Benefits of Employing Power Distribution Unit (PDU)

PDU is designed for simpler and more cost-effective power distribution. And it obtains the following several advantages:

Simplify deployment: The PDU features space-saving, which conserves precious space for network applications, effectively simplify cable management complexities and increase system accessibility. And ultimately contributes to reducing installation time.

Minimize downtime: Rack environments nowadays are more inclined to continuously increase power density. And it happens sometimes to add load in the wrong place and trigger an overload event. The PDU, however, is capable of minimizing this impact to maximum your uptime, achieving high network availability.

Increase power density: PDU is designed to fix your problems of high-density data center environment, and to meet the requirements of your most power-demanding and highest-availability systems.

Streamline cabling: By connecting multiple rack devices to a single PDU using short, easy-to-manage cables, you can significantly reduce the number of power cords extending from the rack to the wall, alleviating clutter and simplifying power distribution.

Five Methods to Enhance Energy Efficiency With PDU

Apparently, the cost concerning energy consumption can be the biggest operating expense in your data center. And here comes to the main purpose of this article: how to improve energy efficiency by the adoption of PDU? Today’s PDU allows data center managers to monitor power use, energy efficiency and environment condition. So, it is possible to make powerful, well-informed decisions to lower energy usage, without negatively impacting data center performance or reliability. There are basically five ways.

Calculate power usage effectiveness (PUE)

PUE helps data center engineers determine energy efficiency by measuring how effectively data centers use input power. It provides insights into efficiency efforts, and can also help determine when something has gone wrong. PDUs can provide power data and help you calculate PUE at a granular level. Total power used in each rack can be compared to the building’s overall power usage to create the foundation for PUE calculation.

Monitor energy-usage trends

Monitoring energy usage enables you to know when consumption gets out of hand. And monitoring each of your PDUs individually would be extremely difficult. However, collecting the information in a database allows you to monitor rack-level power information, store the data, trend it and then use it to make decisions about your data center. When a PDU is reaching its total power capacity level, it can alert the data center manager before breaker capacity is reached and let him/her know that it’s time to bring in more PDUs to prevent outages to computing gears.

Improve capacity planning

When you employ PDUs to perform outlet-level monitoring, you can pinpoint areas within the data center where simple equipment rearrangement may free up power or improve safety by moving equipment that is close to circuit limit. PDUs monitor temperature and other environmental conditions to make sure the performance hasn’t been compromised.

Optimize device-level performance

As you can calculate operating costs of each device, and know how much power each device uses, it is easier to identify the energy hogs. Meanwhile, you can also use device-level performance metrics to determine whether a more efficient device would be worth the investment. PDUs can also identify equipment that is no longer needed. For example, when a PDU indicates that a certain server is running at an average of 35% of peak power, this server can be marked to be replaced.

Quickly correct environmental changes

PDU can identify failed power supply, temperature increases, a sudden surge in power usage. When PDUs alert you to these types of environmental or performance changes via e-mail or text, you should take action before they become a major issue which would lead to downtime and lost revenue.

Conclusion

For each and every data center, reliability is rather critical. PDUs are able to provide robust, reliable power to rack and cabinet applications. And they enable data center managers to enhance energy efficiency by optimizing power capacity, saving large amount of cost, as well as to maximum network uptime. FS.COM offers a wide range of PDUs that are distinguished by their quality, dependability and versatility in electrical applications. Our PDUs are designed specifically to help data center professionals meet rapidly escalating power requirements. For more information, visit www.fs.com.

Originally published: http://www.fiber-optic-solutions.com/pdu-enhance-data-center-efficiency.html

Cabling for Successful Power Over Ethernet (PoE) Installation

The demand for connection from network equipment and devices is accelerating continuously nowadays. And it inevitably leads to the rising cost and complexity of deployment. Therefore, Power over Ethernet (PoE) technology that uses a single twisted-pair cable to provide both data connection and electrical power to devices is employed, for the purpose of less cable usage and investment. PoE has taken a giant leap recently, and we will discuss connectivity and cabling tips for achieving successful PoE deployment in this article.

A Common Description of PoE

Power over Ethernet, often referred to as PoE, is a low voltage technology. It describes a system to safely deliver DC electrical power, along with data, to remote devices over standard data-com cabling or Ethernet cabling. Commonly known as Cat5e or Cat6 cables. PoE has taken a giant leap recently, since it obtains some appealing advantages:

Time and cost savings—by reducing the time and expense of installing electrical power cabling. Network cables do not require a qualified electrician to fit them, and can be located anywhere.

Flexibility— without being tethered to an electrical outlet, devices can be located wherever they are needed most, and repositioned easily.

Safety—PoE delivery is intelligent, and designed to protect network equipment from overload, under powering, or incorrect installation.

Reliability—PoE power comes from a central and universally compatible source. It can be backed-up by an uninterruptible power supply, or controlled to easily disable or reset devices.

Scalability—having power available on the network means that installation and distribution of network connections are simple and effective.

How Does PoE Work?

Power over Ethernet (PoE) demands for a powered device (PD) and power sourcing equipment (PSE) contained in the solution. This ensures that the solution is a complete circuit. A PSE is located at the originating end and generates power and data. The PSE transfers power and data through cat5e or cat6 cable, and delivers it to the PD. The PD serves as an end device that accepts the power and data from the PSE.

Currently Approved PoE Standards

Recent PoE standards enable higher power transmission, which expands the range of devices supported in the enterprise, and to some extent, resulting in the boom of PoE adoption rates. However, higher current PoE brings critical cabling and connectivity considerations when ensuring maximum performance in the network.

Power over HDBASET (PoH) delivers video, audio, 100Mbit/s Ethernet, and power. The POH standard is based on the 802.3at standard, modified to enable delivery of up to 100 W over 4-pair Cat 5e or 6. And TIA and ISO are also currently updating standards that address cabling to support 4-pair PoE in accordance with 802.3bt. TIA TSB-184 guidelines for supporting power delivery over balanced twisted-pair cabling, and ISO/IEC 11801-6 distributed building services working draft are raising requirements to Cat6a cabling to better support IEEE 802.3bt four-pair PoE, as well as other applications.

Cabling for PoE

The heat generation in cable bundles can actually influence network performance to a large extent. High temperatures can lead to higher insertion loss, shorter permissible cable lengths, and higher power costs due to more power dissipated in the cabling. Cable temperatures should not exceed the temperature rating for the cable. The Telecommunications Industry Association (TIA) recommends 15 degrees as the maximum allowed temperature rise above ambient as a result of power over the cabling.

Here are two tips to help lower cabling temperature in PoE deployment:

Tip One: Reduce the Number of Cables Per Bundle

Separating large cable bundles into smaller bundles or avoiding tight bundles helps to minimize higher temperatures. For example, the temperature of a bundle of 91 cables is higher compared to three bundles of 37 cables. And physically separating the three bundles from each other further reduced the maximum temperature.

Tip Two: Use Higher Category Cabling

Higher category-rated cable typically means larger gauge sizes, and as power currents increase, these larger conductors will perform better than smaller cable. The TIA test indicates that higher category-rated cable allowed for larger bundle sizes under the maximum 15-degree temperature increase. The allowable bundle size was 52 cables for Cat5e, 64 for Cat6, 74 for Cat6a. Meanwhile, higher-category cabling is capable of supporting more current capacity at the maximum allowable 15 degrees. (see the figure below).

It is thus clear that higher category cabling is vital to minimize temperature increases. So Cat6a is recommended for all new installations due to the fact that it supports the highest data rate of 10GBASE-T, and has no bundle size limitations with any current or future PoE application.

Conclusion

High quality cabling serves as the fundamental elements for attaining the performance, reliability, and flexibility needed in the PoE. Hence, when cabling for PoE, try to reduce the number of cables per bundle to minimize temperatures. And it is also necessary to choose higher category cabling that allows for larger bundle size and to ensure more current capacity.

Originally published: http://www.china-cable-suppliers.com/cabling-successful-poe-installation.html

Modular Patch Panel Solution for Network Integration

Internet of Things (IoT) fuels the staggering growth of data transmission, making the volume of digital data to expand continuously. Meanwhile, user demand for faster access to all this data is increasing parallelly, therefore further contributing to the seemingly insatiable appetite for bandwidth. With 10G and 40G fiber serving as a commonplace in most data centers today, and it is high time to get your infrastructure prepared for the 100/120G and beyond to integrate higher network speeds. In this article, we’d like to offer module patch panel connectivity as an ideal solution to achieve this goal.

Tendency in Data Centers

When you are about to mix 10G and 40G equipment in your data center, you’d better ensure that the existing network of 10G servers and other devices can be connected to the higher-speed switches you are bringing in. And connectivity with future network standards should also be taken into account. While multiple speeds applications coexist in the same data center is not a fresh topic, the parallel optics cabling used for data transmission speeds of 40G and beyond does present a series of connectivity challenges.

Modular Patch Panel Solution Overview

Modular patch panels are comprised of rack-mountable enclosures designed to house a range of modular, removable fiber cassettes. Supporting various fiber network cabling standards, the cassettes are easy to mix, match, add and replace as your connectivity needs grow and change. Modular patch panels present an ideal way to create a standards-based, flexible, and reliable network platform in data centers.

The key to modular patch panels solution is modular fiber cassettes, which are available in multiple variations. The cassettes allow you to interconnect different fiber speeds simply by plugging standard duplex LC cables into one side of the cassette and one or more standard MPO/MTP cables into the other side.

Benefits and Challenges of Modular Patch Panel Solution

Like every other connectivity solutions, module patch panel solutions offer a range of benefits as well as Challenger.

Benefits:

• Integrate diverse cabling standards—modular patch panel solutions allow you to connect diverse network cabling standards seamlessly, including 10/10G, 10/40G, 40/40G, 10/100/120G and 40/100/120G, as well as future standards.
• Use standard patch cords—Since connections use standard patch cords that are readily available, you can make changes and repairs without the delays and added expense associated with custom cabling.
• Provide flexibility and scalability—as you integrate new cabling standards to support higher network speeds, you can simply swap existing cassettes with new cassettes that support the new standards. Your network can grow and change conveniently, without the costly, labor-intensive process of replacing channels end-to-end.
• Reduce cable congestion—reduced cable slack means less clutter, less confusion and an easily organized, better-labeled cabling infrastructure. You can also manage cables in any direction, be it horizontal or vertical, front or back.
• Support standards—modular patch panel solutions support ANSI/TIA-942 structured network cabling standards for data centers.
• Save space—by managing various port densities and speeds in a single high-density patch panel, you save valuable rack space, helping to lower data center costs. A single patch panel can manage as many as (168) 10G ports.
• Right-size investments—with a modular solution, you can buy and load only the cassettes you need now, while leaving room for future expansion.

Challenges:

The challenge, however, is to select a modular patch panel solution that best fits your demand: with the features and capacity to meet your current needs, and the flexibility and scalability to adapt to and grow with your future needs.

Conclusion

Module patch panel solution provides a feasible and optimum way to network migration and upgrade, ensuring users to integrate equipment with different network speeds seamlessly and conveniently. As well as to satisfy connectivity needs for now and future-proof network for tomorrow.

Originally published: http://www.fiber-optic-solutions.com/modular-patch-panel-solution-network-integration.html

Fiber Patch Cable Selection Guide for 40G QSFP+ Transceivers

Upgrading the existing system to 40G network can be a tough and complicated task since there are considerable amount of factors to plan and design. Whether the switches are capable of supporting such a high speed Ethernet? What kind of optical transceiver works best on the switches? Which optical transceiver is more cost-efficient? 40G QSFP+ transceiver (Quad Small Form-factor Pluggable transceiver) are considered to be the most economical and effective transceiver solutions for 40G migration. The selection for fiber patch cords for interconnection is vital as well.

Patch Cords Matter to 40G

To successfully build 40G transmission network, the switches need to be connected together. In this case, patch cords are usually linked to fiber optic transceivers which are plugged in Ethernet switches (as shown in the following picture), thus to accomplish connections between these switches. The quality of these connections can largely affect the reliability and stability of the whole 40G network. However, connectivity of 40G is much more complex than ever. Thus selecting the proper fiber patch cables for 40G network is more difficult and becomes a critical issue in 40G migration. It is known that QSFP+ transceivers are suggested for 40G, and this article will provide some detailed information about fiber patch cable selection for 40G QSFP+ transceivers.

Selecting Patch Cords for 40G QSFP+ Transceivers

Patch cords selection is a big issue to 40G not only because the switch connections necessity, but also because of the transmission principle of the fiber optic signals and the high density trend of 40G transmission. Several important factors should be taken into account when selecting patch cords for 40G QSFP+ transceivers, which are cable type, connector type and switch port.

Cable Type

Performances of optical signals often vary from different wavelengths. Even optical signals with the same wavelength perform totally different when they run through different fiber optic cables. Thus, the selection of the cable type is essential.

A typical question that frequently asked when buying fiber optic patch cords for 40G QSFP+ transceiver can illustrate this point clearly. Can a 40GBASE universal QSFP+ transceiver working on wavelength of 850 nm be used with OM1 patch cords? The answer is yes, but not suggested. As the optical signal transmission distance gets shorter as the data rate increases, the transmission distance and quality would be limited by using OM1 patch cords with 40G QSFP+ transceiver. OM1 cable is only suggested for 100Mb/s and 1000Mb/s transmission. Two upgraded cables—OM3 and OM4 are suggested for 40G QSFP+ transceivers in short distance.

IEEE has announced standards for 40G transmission in both long distance and short distance, which are 40GBASE-SR4 and 40GBASE-LR4(SR stands for short-reach and LR stands for long reach). The 40GBASE-LR4 is suggested for 40G transmission over single-mode fiber in long distance up to 10 km. Whereas the 40GBASE-SR4 is for 40G transmission in short distance over multimode fiber—OM3 (up to 100 meters) and OM4 (up to 150 meters). OM3 and OM4, which are usually aqua-colored, are accepted economical solutions for 40G in short distance with lower insertion loss and higher bandwidth.

Connector Type

The connector type of the patch cords depends on the interface of 40G QSFP+ transceiver. Currently there are two interfaces commonly adopted by 40G QSFP+ transceiver, which are MPO and LC. Usually 40G QSFP+ transceiver with MPO interface is designed for short transmission distance and LC for long transmission distance. However, several 40G QSFP+ transceivers like 40GBASE-PLR4 and 40GBASE-PLRL4 have MPO interfaces to support long transmission distance.

High density is the most obvious features of 40G transmission, which is largely reflected in the MTP connectors on patch cords used with 40G QSFP+ transceiver. As QSFP+ transceiver uses four 10G channels to achieve the 40G transmission, thus 4 pairs of fibers are used and the 12-fiber MTP connectors can provide a time-saving and stable solution for 40G QSFP+ transceivers. However, for multi-fiber connection, polarity should be considered for the selection of the patch cord.

However, to meet the market demands, 40G QSFP+ transceiver with LC interface is also available. This type of QSFP transceiver uses four lanes with each carrying 10G in 1310nm window multiplexed to achieve 40G transmission. For this type, patch cable with duplex LC connector should be used.

Switch Port

Network flexibility becomes more crucial as the speed of Ethernet increases. When it comes to 40G, network flexibility becomes an urgent issue which is closely related to applications. Right selection of patch cords for 40G QSFP+ transceiver can increase the network flexibility significantly and effectively. Here offer two most common examples in 40G applications: 40G QSFP+ to 40G QSFP+ cabling and 40G QSFP+ to SFP+ cabling.

For 40G QSFP+ to 40G QSFP+ cabling:

1. For distance up to 100 m, the 40GBASE-SR4 QSFP+ transceiver can be used with OM3 fiber patch cable attached with a MPO on each end.

2. For distance up to 150 m, the 40GBASE-SR4 QSFP+ transceiver can be used with OM4 fiber patch cable attached with a MPO on each end.

3. For distance up to 10 km, the 40GBASE-LR4 QSFP+ transceiver can be used with single-mode fiber with LC connectors. The picture above shows the transmission of 40GBASE-LR4 QSFP+ transceiver with LC connector over single-mode fiber.

It’s very common that 40G ports are needed to be connected with 10G port. In this case, fan out patch cable with MTP connector on one end and four LC duplex connectors on the other end is suggested (as shown in the picture below).

Conclusion

Fiber optic patch cords hold an essential position in connecting and accomplishing the whole 40G transmission network. When selecting the right patch cable for 40G QSFP+ transceiver, cable type, connector type and switch port should be taken into consideration, since these three factors are closely relevant to transmission distance, network flexibility and reliability of the whole 40G network. What we discussed above simply offers you a reference guide. For professional and cost-effective network design as well as 40G products, please visit www.fs.com.

First published: http://www.fiber-patch-cords.com/blog/a/133/Fiber-Patch-Cable-Selection-Guide-for-40G-QSFP+-Transceivers

Serial Transmission vs. Parallel Transmission

We know that in data centers and server farms, when peripherals are attached to a computer, a physical cord is required to send signals back and forth. In this case, the processor can communicate with these devices and send data to them. Communication occurs when the computer sends electronic pulses to the peripheral or vice-versa. Basically, there exist two primary types of digital data transmission—serial transmission and parallel transmission. Then, is there any difference between these two methods of data transmission? How to apply them in data center connectivity? This is what exactly we are going to discuss.

Serial Transmission and Parallel Transmission Overview

For each and every data transfer, the same protocol should be applied to the emitter and the receiver. It enables them to have the same level of information and to know the transfer speed of the data. There are numerous protocols though, and all protocols rely on these two transmission methods: serial transmission and parallel transmission.

Serial Transmission

In serial transmission, bits are sent sequentially on the same channel (wire), one bit at a time. In this way, it reduces costs for wire but also slows the speed of transmission. Also, for serial transmission, some overhead time is needed since bits must be assembled and sent as a unit and then disassembled at the receiver. Serial transmission can be either synchronous or asynchronous.

Parallel Transmission

In parallel transmission, multiple bits (usually 8 bits or a byte/character) are sent on different channels (wires, channels) simultaneously within the same cable, or radio path, and synchronized to a clock. Parallel devices can transfer data in words of one or more bytes at a time. Consequently, there is a speedup in parallel transmission bit rate over serial transmission bit rate, and the cost increasing parallelly since multiple wires cost more than a single wire. As the cable gets longer, the synchronization timing between multiple channels becomes more sensitive to distance. Unlike serial transmission, parallel transmission is considered synchronous.

Transmission Methods Applied in Data Centers

We know that both serial transmission and parallel transmission take a seat in data center connectivity, but in different situations and applications. In the following parts, we will illustrate it in details.

Serial Transmission for 10G Network

Serial transmission approach is usually employed in 10G fiber connectivity where the data are sent sequentially. A duplex fiber pair that consists of one dedicated transmission fiber and one dedicated reception fiber creates the 10G channel to complete the data circuit. Typically, serial connectivity is achieved by using a duplex LC connector. The LC connector is the most commonly deployed interconnect in data centers, especially for high-density network applications.

Parallel Transmission for 40G Network and Above

Currently, it’s still not feasible yet possible to adopt a single duplex fiber for beyond 10G network. Although, the technical advancements in serial transmission have raised the limit to 25G, 40G network and above demands for parallel transmission since it can transport more data and achieve higher speeds. For example, parallel transmission achieves the 40G speed by combining four 10G duplex fiber pairs to create a 40G channel. A 100G channel would include ten 10G duplex fiber pairs, and so on. The same principle applies for 120G network and higher.

However, parallel transmission principles can also be applied to 25G duplex fiber pairs to reach even higher speeds or reduce the number of fibers required at a given speed. For instance, a 100G channel would require four 25G duplex fiber pairs instead of ten 10G duplex fiber pairs.

In parallel transmission, MPO/MTP connectors are used to achieve connectivity. They either house 12 or 24 fibers (6 or 12 duplex fiber pairs). This connectivity option finds itself a better place in data centers because it can take advantage of low-cost lasers and multi-mode cables. Equipment designed for speeds of 10G or less has two-strand, duplex fiber ports for serial transmission, while 40G and 100/120G equipment has 12- and 24-strand MPO/MTP fiber ports for parallel optics transmission.

Conclusion

As the basic digital data transmission approaches, serial transmission is often used in 10G connectivity or data transfer with great distances. While for 40G and beyond or short distance transmission, parallel transmission is preferred. Hope you could acquire some useful information from the article, and have a better understanding of these two data transmission methods.

First published: http://www.china-cable-suppliers.com/serial-transmission-vs-parallel-transmission.html

Cut Out Costly Mistakes With Fiber Optic Cleaver

There is no doubt that cleaving the fiber properly is critical to achieve good fiber optic splices or terminations, especially when using the pre-polished connectors with internal splices. Imprecisely cleaving of the fiber ends, therefore, will result in improper matching. So, the end of the fiber must be cleaved to a 90 degree flat end when it is prepared for a connector or splice. However, technicians often encountered the problem that the end of the fiber strand is so small, making it is impossible to tell whether the strand has a flat end. To ensure smooth and precise fiber cleaving, a fiber optic cleaver is much needed. And in this article, we will offer you some useful information about fiber optic cleaver.

What Is Fiber Optic Cleaver?

A cleave in an optical fiber is a deliberate, controlled break, which intends to create a perfectly flat end face, perpendicular to the longitudinal axis of the fiber. A fiber optic cleaver is a tool that holds the fiber under low tension, scores the surface at the proper location, then applies greater tension until the fiber breaks. Usually, after the fiber being scored, the technician will use a cleaver either bends or pulls the fiber end, stressing the fiber. And the fiber will break at the score mark under this stress, leaving a 90 degree flat end if all goes well. So the cleaver doesn’t cut the fiber but just breaks the fiber at a specific length.

Two Types of Fiber Optic Cleavers

We know that the closer to 90 degrees the cleave is, the greater chance you will have to match it with another cleaved fiber, then be spliced or mated by a connector. Thus, a proper tool with good technique is demanded for consistently achieving a 90 degree flat end. Good cleavers are automatic and can produce consistent results, irrespective of the operator. The user only needs to clamp the fiber into the cleaver and operate its controls. Some cleavers are less automated, making them more dependent on operator technique and therefore less predictable. There are basically two broad categories of fiber optic cleavers: scribe cleavers and precision cleavers.

Scribe Cleavers

This type is based on a traditional cleaving method. It is typically used to remove excess fiber from the end of a connector before polishing, simply by using a hand tool called scribe. Scribe cleavers are usually shaped like ballpoint pens with diamond tipped wedges or come in the form of tile squares. The scribe has a hard, sharp tip, generally carbide or diamond, which is used to scratch the fiber manually. Then the operator pulls the fiber to break it. Since both the scribing and breaking process are under manual control, this method varies greatly in repeatability. Most field and lab technicians shy away from these cleavers as they are not accurate. However, if used in skilled hands, this scribe cleaver reduces the cost significantly for repairs, installation, and training classes.

Precision Cleavers

Precision cleavers are the most commonly used cleavers in the industry. They use a diamond or tungsten wheel/blade to provide the nick in the fiber. Tension is then applied to the fiber to create the cleaved end face. The advantage of these cleavers is that they can produce repeatable results through thousands of cleaves by simply rotating the wheel/blade accordingly. Although more costly than scribe cleavers, precision cleavers can cut multiple fibers at one time with increased speed, efficiency, and accuracy. While in the past, scribe cleavers were widely used for fiber cleaving, precision cleavers are now developed to support various applications and multiple fiber cleaving. Precision cleavers contribute to better cleave, which ensures low splice loss and precision cleavers, besides, its blades have a much longer life span.

Which One to Use: Scribe Cleaver or Precision Cleaver?

Then here comes the question: how to choose between scribe cleaver and precision cleaver? You can take this for reference: An experienced fiber optic technician achieves approximately 90% good cleaves with a scribe cleaver, while for precision cleaver, it produces 99% good cleaves. Since the difference is not big enough to help make a choice, I humbly suggest you to buy precision cleavers if you plan to use a lot of mechanical splices or pre-polished splice/connectors. And this will benefit you from the long run. If you decide to use inexpensive scribe cleavers, you’d better to learn how to use it properly. Follow directions, but also do what comes naturally to you when using the device, as they are sensitive to individual technique. Inspect the fibers you cleave to see how good they are and keep practicing until you can make consistently good cleaves.

Conclusion

Fiber optic cleaver serves as an essential tool to get better fiber cleaving, which as well contribute to the fiber splice and termination. There are two types of fiber optic cleaver available: scribe cleaver and precision cleaver, and you can choose one based on your specific requirements and applications. But no matter what you choose, enough practicing is needed to get consistently good cleavers.

First published: http://www.fiber-optic-solutions.com/cut-costly-mistakes-fiber-optic-cleaver.html