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OM5 fiber technology standard and data center application

       The ISO and TIA standardization organizations released the latest wiring standards ISO 11801 3rd and TIA-568.0-D in 2017. The new standard removes the traditional OM1, OM2 multimode fiber optic cable and adds OM5 broadband multimode fiber optic cable. ISO reduces the attenuation of OM5 cables from 3.5 dB/km for previous OM3, OM4 cables to 3.0 dB/km, and increases the bandwidth requirement at 953 nm.

  ISO/IEC JTC1SC25 WG3 new project ISO/IEC TR 11801-9908 has released the first draft of WD to study wiring guidelines for high-speed network applications on multimode fiber, 10/40/100/200/ The transmission distances of OM3, OM4, and OM5 multimode fibers under 400G duplex and parallel network applications were studied.

  OM5 multimode fiber supports more wavelength channels, so the direction is the same for SWDM4 with four wavelengths or BiDi with dual wavelength. Similar to BiDi for 40G links, SWDM transceivers only require a two-core LC duplex connection, except that SWDM operates on four different wavelengths between 850 nm and 940 nm, one of which is dedicated to The signal is transmitted and the other fiber is dedicated to receiving the signal.

  OM5 fiber supports both future 400G Ethernet, for higher speed 400G Ethernet applications such as 400G Base-SR4.2 (4 pairs of fiber 2 wavelengths, 50G PAM4 per channel) or 400G Base-SR4.4 (4 For 4 wavelengths of fiber, 25GNRZ for each channel, only 8 cores of OM5 fiber are required. Compared with the first generation of 400G Ethernet 400G Base-SR16 (16 pairs of fibers, each channel transmits 25Gbps), the required number of fibers is only For a quarter of traditional Ethernet, SR16 is a milestone in the development of multimode 400G technology, demonstrating the possibility of multimode technology supporting 400G. In the future 400G mass application market, 400 multimode applications based on 8-core MPO are expected.

  As the physical transmission medium of data communication, optical fiber provides support for network equipment. The promotion of OM5 fiber cannot be separated from the support of network equipment manufacturers.

  There are currently two technologies for transmitting high-speed networks with a small amount of fiber on the market: BiDi and SWDM4. From the perspective of the industry chain, OM5 multimode fiber and BiDi and SWDM4 equipment manufacturers form an industry alliance, but whether this ecosystem can mature depends on the shipment of these 40/100G network equipment and the large deployment of OM5 fiber. The OM5 multimode fiber test is identical to the traditional OM3, OM4 multimode fiber test equipment, and test procedures, and the user does not need to purchase additional test equipment.

  The data center needs to be upgraded to 200/400G or higher in the future. It will have to face many optical module types such as MSA. In the absence of an IEEE standard project, users also need to care about whether there is open and standardized multimode wavelength multiplexing. Technology has emerged, and low-cost VCSEL 100G technology cannot achieve breakthroughs and other issues. Regardless of whether a parallel transmission optical module or a duplex transmission optical module is used in the future, network cabling is an important network infrastructure of the data center. It can be determined that the data center cabling must be open, scalable and flexible to support A variety of network architecture applications.

  Responsible Editor: DJ Editor

Original Article Source http://www.jifang360.com/news/2019426/n8147118755.html

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How to manage the optical fiber jumper of the integrated wiring system

In general, reasonable jumper management can be divided into five phases: planning, preparation, wiring, testing, and verification.

1 jumper operation specification

1.1 plan

Pre-establishment, no pre-emptive, and doing everything in advance requires detailed planning in advance. For jumper management, you should plan your current and future needs.

(1.1.1) Change request. Various management activities, moves, additions, or changes (MACs) begin with a change request. The change request must contain all the necessary information to start the planning process.

(1.1.2) Search records. After receiving the request form, the record should be searched to determine the circuit path used.

(1.1.3) Correct routing. Before determining the correct jumper length, first, find the best route between the ports to be connected. It is usually the shortest path through the horizontal and vertical cable conduits and must not obstruct or obstruct other jumpers or connectors in the patch panel. Select jumpers, avoid excessive slack and ensure a neat appearance. Too tight a jumper will increase the tension on the connector, and excessive slack will cause trouble for jumper management and increase the management difficulty of the patch panel.

1.2 Preparation

After making the plan for jumper management, you should follow the plan prepared in advance, and then you should prepare for the jumper management. Prepare as much as possible before conducting management operations to study management records. Determine the location of the port that needs to be connected and reconnected and the label information of the relevant port.

(1.2.1) First, check the model that requires the jumper, and then check the quality of the jumper. In order to ensure that the quality of the jumper is correct, it is necessary to check whether the jumper is damaged. In order to check whether it is damaged, you can first check it from the appearance of the jumper. If you have the condition, you can check it with a professional instrument.

(1.2.2) Next, check the condition of the joint to avoid physical damage to the joint.

(1.2.3) Finally, it is necessary to clean the jumper connector and the connection part.

There are two methods for cleaning the fiber optic connector: contact and non-contact:

Contact cleaning method:

(1) Wiping paper and anhydrous alcohol, using original wood pulp with special processing technology, ultra-low dust, pure texture, high-efficiency water absorption, fine paper, will not scratch the surface of the inserted object, use low dust wipe paper with no Water alcohol wipes the fiber optic connector;

(2) Non-woven fabric, no lint, strong, no chemical impurities, silky soft, does not cause allergic reactions and is not easy to fluff and hair loss, is produced or tested as a fiber optic connector or pin Ideal for cleaning wipes, wipe the fiber optic connector with anhydrous alcohol during use.

(3) Cleaning cotton swabs, specially designed for internal cleaning of ceramic bushings, or for cleaning ferrule end faces that are not easily accessible in flanges (or adapters);

(4) Professional cleaners, special cleaners for fiber optic connectors use a special role of wiping tape, which can be installed in a rollable casing without alcohol. Each cleaning is very effective and produces a new surface, which is convenient and practical.

Non-contact method:

(1) Ultrasonic cleaning method, which turns the cleaning liquid into an ultrasonic “liquid column” and sends it to the end face of the connector, and recovers and absorbs the waste liquid in the same small space;

(2) High-pressure blowing method, the principle is that the cleaning liquid is first applied to the end face of the connector, and then the high-pressure gas is used to align the end face of the connector;

(1.2.4) Check the cleaning of the fiber connector

After cleaning the fiber optic connector, the termination faces must be inspected. The general practice is to use a magnifying glass of 100, 200 or 400 times. The figure below shows the state of the fiber termination surface in a clean state and after being contaminated.

Jumper managers, no matter what method is used, are difficult to clean for some heavily contaminated connectors and need to be treated with a cleaning solution such as cotton swabs and alcohol.

After this series of preparations, it means that the wiring work of the jumper management can be carried out.

1.3 wiring

The installation of the distribution frame shall be completed at various stages in accordance with the operating procedures. Kink knots, burrs, pinches, and poor contact in jumper construction can significantly reduce jumper performance. To avoid such problems, the following factors should be considered:

(1) Bending radius

The minimum bend radius allowed for the jumper is subject to the jumper manufacturer’s specifications.

The standard stipulates that the minimum bend radius of unshielded twisted pair (UTP) should be four times the diameter of the cable, and the shielded twisted pair is eight times the diameter of the cable. The minimum bend radius of a 2-core or 4-core horizontal cable is greater than 25 mm. If the bend radius is less than this standard, the relative position of the wire may be changed, resulting in a decrease in transmission performance.

(2) Jumper stretching and stress

During the wiring process, do not use excessive force, otherwise, the stress on the jumper and the connector may be increased, resulting in performance degradation.

(3) Bundling

Jumpers do not necessarily need to be bundled. If the strapping needs to comply with the manufacturer’s strapping principle, do not bundle too tightly, otherwise, it will cause the twisted pair to be deformed. Do not overtighten the clamps. It is advisable to rotate the jumpers freely. Use a dedicated product and consider a product that can be used repeatedly without tools, such as a Velcro tape.

1.4 test

(1) Although it has been completed by jumper wiring, it may not be considered whether the fiber link or copper link fully complies with the operating specifications or the international standard of the integrated wiring, then the fiber or copper cable test should be carried out. After the test standard is met, it can be determined whether the test standard has passed.

1.5 verification

(1) It is worthwhile to spend some time on the final visual inspection of the connection. Make sure that the jumper is not kinked and is not caught by the cabinet door.

(2) The last step is to update the record according to the current configuration and close the work order related to the changed request that has been executed.

Jumpers are now an important part of the cabling system, especially for the good management of jumpers in data center projects. It is believed that as long as the construction management personnel correctly and reasonably jumper management operations, the entire integrated wiring will become a truly advanced, scientific, practical, and reliable system.

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Fiber type

Fiber type

The following is a description of the most common types of communication fibers.

MMF (multimode fiber)

OM1 fiber or multimode fiber (62.5/125)

OM2/OM3 fiber (G.651 fiber or multimode fiber (50/125))

SMF (single-mode fiber)

– G.652 (dispersion non-displaced single-mode fiber)

– G.653 (dispersion-shifted fiber)

– G.654 (cutoff wavelength shifting fiber)

– G.655 (non-zero dispersion-shifted fiber)

– G.656 (low slope non-zero dispersion shifted fiber)

– G.657 (bend-resistant fiber)

As long as the optical budget allows, technically, any suitable fiber can be applied to FTTx technology, but the most commonly used fibers for FTTx technology are G.652 and G.657.

G.651 (multimode fiber)

G.651 is mainly used in local area networks and is not suitable for long-distance transmission. However, in the range of 300 to 500 meters, G.651 is a low-cost multimode transmission fiber.

ITU-T G.651 fiber is OM2/OM3 fiber or multimode fiber (50/125). There is no OM1 fiber or multimode light (62.5/125) in the ITU-T recommended fiber.

The reflectivity of the multimode fiber (50/125) core gradually changes from the center to the cladding, allowing multiple optical transmissions to be performed at the same speed.

G.652 fiber (dispersion non-displaced single-mode fiber)

The most common single mode fiber in the world. The dispersion that distorts the signal at a wavelength of around 1,310 nm can be minimized. You can use a 1550 nm wavelength working window for short-range transmission or with dispersion-compensating fiber or with a module.

G.652A/B is a basic single-mode fiber, and G.652C/D is a low-water peak single-mode fiber.

G.653 (dispersion-shifted fiber)

This fiber minimizes dispersion at around 1,550 nm, minimizing light loss.

G.654 (cutoff wavelength shifting fiber)

The official name of G.654 is a cut-off wavelength shifting fiber but is commonly referred to as a low-attenuation fiber. The low attenuation characteristics make G.654 fiber mainly used for long-distance transmission on the seabed or on the ground, such as 400 km transponder-free lines.

G.655 (non-zero dispersion-shifted fiber)

G.653 fiber has zero dispersion at 1,550 nm, while G.655 fiber has concentrated or positive or negative dispersion, which reduces the adverse effects of nonlinear phenomena that interfere with adjacent wavelengths in DWDM systems.

The first generation of non-zero dispersion-shifted fibers, such as PureMetro® fibers, have the advantage of having a dispersion of 5 ps/nm or less per kilometer, making dispersion compensation easier. The second generation of non-zero dispersion-shifted fibers, such as PureGuide® dispersion, reached around 10ps/nm per kilometer, doubling the capacity of DWDM systems.

G.656 fiber (low slope non-zero dispersion shifted fiber)

One of the non-zero dispersion-shifted fibers has strict requirements on the speed of dispersion, ensuring transmission performance over a larger wavelength range in DWDM systems.

G.657 (bend-resistant fiber)

The newest member of the ITU-T fiber family. New products based on the needs of FTTx technology and assembly applications.

G.657A fiber is compatible with G.652 fiber, and G.657B fiber does not need to be compatible with traditional single mode fiber.

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Comparison of fiber optic patch cords OM1, OM2, OM3 and OM4

As is well known, “OM” stands for optical multi-mode, that is, optical mode is a standard for multimode fiber to represent fiber grade. The bandwidth and maximum distance are different when transmitting at different levels, but there are often friends who have doubts about the difference between the optical fiber jumpers OM1, OM2, OM3, and OM4. Let Xiaobian explain the fiber jumpers OM1 and OM2 for everyone. The difference between OM3 and OM4.

LC-LC OM4 Duplex Fiber Cable

What is the difference between fiber optic patch cords OM1, OM2, OM3, and OM4?

1. Comparison of parameters and specifications of OM1, OM2, OM3 and OM4 fibers

1. OM1 refers to a 50um or 62.5um core-diameter multimode fiber with a full injection bandwidth of 200/500MHz.km at 850/1300nm;

2. OM2 refers to a 50um or 62.5um core-diameter multimode fiber with a full injection bandwidth of 500/500MHz.km at 850/1300nm;

3. OM3 is an 850nm laser-optimized 50um core-diameter multimode fiber. In 10Gb/s Ethernet with 850nm VCSEL, the fiber transmission distance can reach 300m.

4. OM4 is an upgraded version of OM3 multimode fiber, and the fiber transmission distance can reach 550m.

Second, the design comparison of OM1, OM2, OM3, and OM4 fiber

1. The traditional OM1 and OM2 multimode optical fibers are based on LED (Light Emitting Diode) as the basic light source, and OM3 and OM4 are optimized on the basis of OM2, making them suitable for the light source. For the transmission of LD (Laser Diode);

2. Compared with OM1 and OM2, OM3 has a higher transmission rate and bandwidth, so it is called optimized multimode fiber or 10G multimode fiber;

3, OM4 re-optimized on the basis of OM3, with better performance.

Third, the function and characteristics of OM1, OM2, OM3, and OM4 fiber

1. OM1: large core diameter and numerical aperture, strong light collecting ability and bending resistance;

2, OM2: core diameter and numerical aperture are relatively small, effectively reducing the mode dispersion of multimode fiber so that the bandwidth is significantly increased, the production cost is also reduced by 1/3;

3, OM3: the use of flame-retardant skin, can prevent the spread of flame, prevent the emission of smoke, acid gases, and toxic gases, and meet the needs of 10 GB / s transmission rate;

4. OM4: Developed for VSCEL laser transmission, the effective bandwidth is more than double that of OM3.

Fourth, the application comparison of OM1, OM2, OM3, and OM4 fiber

1. OM1 and OM2 have been widely deployed in buildings for many years, supporting Ethernet transmission with a maximum of 1GB;

2, OM3 and OM4 fiber optic cable is usually used in the hiring environment of the data center, supporting the transmission of 10G or even 40/100G high-speed Ethernet road.

5. When do you use OM3 fiber jumpers?

OM3 fiber is designed to work with VCSEL and meets the ISO/IEC11801-2nd OM-3 fiber specification to meet the needs of 10 Gigabit Ethernet applications. There are many types of OM3 fiber, including indoor type, indoor/outdoor versatility, etc. The number of cores of the fiber is from 4 cores to 48 cores. It also supports all applications based on older multimode 50/125 fiber, including support for LED sources and laser sources.

1. The transmission distance of Gigabit Ethernet using OM3 fiber system can be extended to 900 meters, which means that users do not have to use expensive laser devices when the distance between buildings is more than 550 meters.

2. Within the distance of 2000 meters, standard 62.5/125μm multimode fiber can be used in all cases within the OC-12 (622Mb/s) rate range, and single-mode fiber will be used. However, the emergence of OM3 multimode fiber has changed this situation. Since OM3 fiber can increase the transmission distance of Gigabit and 10 Gigabit systems, the use of 850 nm wavelength optical module in conjunction with VCSEL will be the most cost-effective cabling solution.

3. When the link length exceeds 1000 meters, single-mode fiber is still the only choice. Single-mode fiber can achieve 5 km transmission distance at 1310 nm in Gigabit system, and 10 km in 10 Gigabit system. Transmission distance.

4. When the link length is less than or equal to 1000 meters, OM3 50μm multimode fiber can be used in the Gigabit system, and single-mode fiber should be used in the 10G system.

5. When the link length is less than 300 meters, OM3 multimode fiber can be applied to any Gigabit and 10 Gigabit systems.

6. When do you use OM4 fiber patch cords?

For a typical link, the cost of an optical module is about expensive. Although single-mode fiber is cheaper than multimode fiber, the use of single-mode fiber requires a very expensive 1300nm optical module, which costs about 2-3 times that of an 850nm multimode optical module. In general, a multimode fiber The system cost is much lower than that of a single-mode fiber system.

When investing in fiber-optic cabling, if you can consider adding some initial investment in wiring, using better multimode fiber, such as OM4 fiber, you can ensure that the current multi-mode fiber technology is fully utilized to reduce the overall cost of the current system; When upgrading to higher speed systems, such as 40G and 100G, OM4 is still available and will be more cost-effective.

In summary, when the transmission rate is greater than 1 Gb/s, the use of multimode fiber is a good system choice. When the system requires a higher transmission rate, the following are the guidelines for our choice of OM4 fiber:

1. For Ethernet users, the transmission distance can reach 300m to 600m in 10Gb/s system transmission; in 40Gb/s and 100Gb/s systems, the transmission distance is 100m to 125m.

2. For campus network users, OM4 fiber will support 4Gb/s fiber link length of 400m, 8Gb/s fiber link length of 200m or 16Gb/s fiber link length of 130m.

to sum up

Multimode fiber technology has evolved from OM1 multimode to OM4, which now supports 10Gbps, which will give users the most effective return on investment and become the best choice for backbone cabling or fiber to the desktop. After reading this article, I believe I have already answered your questions about the difference between the fiber jumpers OM1, OM2, OM3, and OM4.

Disclaimer: All information indicated as other sources is transferred from other platforms, the purpose is to convey more information, does not represent the views and positions of this site. Please contact us if there is any infringement or objection.