MPO Cable Testing Overview

by Fiber-MART.COM

 

Nowadays, the existing bandwidth is not adequate to meet enterprises’ increasing appetite. In the meanwhile, optical technologies like cloud computing, virtualization and storage area networks are all in the fast development, which pushes the further development of higher-bandwidth tech like 40/100G Ethernet. Thus under this circumstance, new devices are greatly required. Besides the new optical transceivers and fiber optic cables, a steady proliferation of fiber connections—MPO (Multifiber Push-On) came into being.

 

MPO cables, featured by its compact, pre-terminated advantages, has become the default cabling solution for the increasing bandwidth requirements. However, a flaw of the MPO cable may hinder its development. The testing process of the MPO cable can be complex and error-prone. Have you been through the scene? When you prepare to test a MPO cable, you have to throw polarity of all 12 fiber connections into the mix. And if it comes to migrating 10 Gbps to 40/100 Gbps on the same cable, all the testing job you have done is in vain. Since the testing process is pretty uneasy, The following text will provide some detailed information about it to help you do the right MPO cable testing.

 

Problems You Should Know About MPO Cable Testing

 

Typically, a MPO cable contains 12 optical fibers, and each fiber is thinner than human’s hair. So if you want to test the cable, you must test every fiber of it, which is quite difficult for inexperienced engineers. The common way to do this is to use a fan-out cord to make the 12 fibers separate, then testing. One fiber testing would take you 10 seconds. So if your customer ask you to test 48 MPO trunks cable in data center which has a 30,000-MPO data center installation, that means you need to spend 3,120 hours. Such a huge project! To avoid this expensive and time-consuming process, modular factory-terminated MPO cables promise simplicity, lower cost, and true plug-and-play fiber connectivity.

 

Additional, when you are about to test a MPO cable, you should check whether the MPO cable is in the good state. Because cables must be transported, stored, and later bent and pulled during installation in the data center, which may lead to the performance uncertainties before fiber cables are deployed. Proper testing of pre-terminated cables after installation is the only way to guarantee performance in a live application.

 

What’s more, fiber polarity is also an important factor you should take into account. The simple purpose of any polarity scheme is to provide a continuous connection from the link’s transmitter to the link’s receiver. For array connectors, TIA-568-C.0 defines three methods to accomplish this: Methods A, B and C. Deployment mistakes are common because these methods require a combination of patch cords with different polarity types.

 

The Relationship Between Bandwidth and Testing

 

The market trend of telecom industry implies that 10G network has already been deployed in a large scale. And now 40G is main stream. As for 100G, people also already prepare for it. So bandwidth would always be a hot topic.

 

We have said before that MPO cable can solve the problem of bandwidth. As data center bandwidth steadily climbs to 10, 40, and 100Gbps, a dense multi-fiber cable becomes the only option. That’s why the use of MPO cables has steadily risen over the past 10 years. With the MPO cabling system, 40/100G migration path seems to be a simple and easy solution. Just remove the 10Gbps cassette from the MPO cable and replace it with a bulkhead accommodating a 40Gbps connection. Later it might be possible to remove that bulkhead and do a direct MPO connection for 100 Gbps at a later date. Figure 2 shows a 40G connectivity with the use of the 12-fiber MPO cable. A 40G QSFP like QSFP-40G-SR4 connects to a 12-fiber MPO cable. A 12-fiber MPO fanout cable is also used to connect four 10G SFP+ transceivers like 46C3447 with a MPO FAP.

 

The problem is that while this migration strategy is an efficient way to leverage the existing cabling, in comparison to 10Gbps connections, the 40Gbps and 100Gbps standards call for different optical technology (parallel optics) and tighter loss parameters. In short, each time you migrate you need to verify the links to ensure the performance delivery the organization requires.

 

How to Do the Proper MPO Cable Testing

 

When you move to this part, you may think that MPO testing may be a tough obstacle for us to conquer. So is there a simple way to do the testing? The answer is yes. You can just test all 12 fibers—the whole cable—simultaneously and comprehensively (including loss and polarity). That sort of test capability changes the fiber landscape, enabling installers and technicians to efficiently validate and troubleshoot fiber—flying through the process by tackling an entire 12-fiber cable trunk with the push of a button.

 

To do a proper MPO cable testing, you must need some proper testing tools as shown in Figure 3. The tools to perform this type of test are emerging on the market, and promise to reduce the time and labor costs up to 95% over individual fiber tests. Characteristics to look for in such a tool include the following parts.

 

An onboard MPO connector to eliminate the complexity and manual calculations associated with a fan-out cord.

A single “Scan All” test function that delivers visual verification via an intuitive interface for all 12 MPO fibers in a connector.

Built-in polarity verification for end-to-end connectivity of MPO trunk cables.

“Select Individual Fiber” function that enables the user to troubleshoot a single fiber with more precision.

 

Summary

 

The insatiable need for bandwidth ensures that the integrity of the data center, which has also become inextricably linked to the strength of the fiber cabling infrastructure. Now more and more MPO trunk cables are put into use, to make sure the better performance, you should be able to test the MPO connection. Fiberstore offers a variety of MPO products including MPO trunk cables, MPO harness cable, 12-fiber or 24-fiber MPO cable and so on. All of our products can also be customized. Please feel free to contact us.

sing Fiber Optic Transceiver to Achieve Long Distance Transmission

by Fiber-MART.COM

Recently we met a big project that involved the network channel installation about digital optical transmission equipment, in fact, it is not so complex as the organization network ways, just we can use with SDH and downward access with switches over backbone line, but because of the SDH equipment covers all the site in the progress of construction, so it need to be solved for long distance network connections by another way. Fortunately, we have much experiences in using fiber optic transceiver, this page we will introduce the application of fiber optic transceiver in the network construction progress which combines with this experience.

 

1. Multimode fiber optic transceiver and multimode fiber optic cables

Fiber optic transceiver is an ethernet transmission device that can exchange the light signal and electrical signal, fiber optic cables that can transfer data over network can be divided into multimode fiber optic cables and single-mode fiber optic cables, fiber core diameter of multimode fiber cable is 50~62.5 Ľm and the single-mode fiber cable core diameter is 8.3 Ľm. In fact, these data are not intuitive for us, we can judge it only by colors, the multimode fiber pigtail's color is orange and the single-mode fiber cable is yellow. From the network applications, because of multimode fiber optic cable can transmit for not tool long distance, it just can be used between the buildings, but because of the price is relatively cheap, so there are still some people like to use it. HP J4858C SFP transceiver in figure 1.

 

Figure 1. HP J4858C SFP 850nm 550m Multimode Optical Transceiver

 

HP J4858C

 

2. Single-mode fiber optic transceiver series

With the development of technology, this phenomenon that single mode fiber cables applied into the long distance network installation is more and more popular, nowadays many customers use fiber optic transceiver directly, just we call it FTTH (fiber to the home), and these different types of fiber optic transceivers we will introduce to you all based on single mode fiber cables. HP transceiver JD119B Single-Mode SFP in figure 2.

 

Figure 2. HP JD119B X120 1310nm 10km Single-Mode Optical Transceiver

 

HP transceiver JD119B

 

Dual Fiber Single Network Port

The dual fiber single network port fiber optic transceiver just use two fibers, a fiber is used to receive and another is used to transmit. A group of fiber optic transceivers can achieve the exchange of electrical signal and light signal. The network device may a switch, also may a server, well, we can see the fiber optic transceiver as PC, which connected with the switch is straight through cable, and with the server is cross cable. With the development of technology, the fiber optic transceiver ports have been generally made adaptive mode (automatic matching cross-line and direct line), it also bring conveniences to the projects.

 

Single Fiber Single Network Port

With the continuous development of business, we are faced with an unavoidable problem that the shortage of fiber resources. Some companies want to connect the network but there is only a fiber, it is time to use the single mode fiber optic transceiver, it means that receive and transmit signal over a fiber, this product use WDM technology, related product: passive cwdm mux (shown as the figure). The wavelength usually are 1310nm and 1550 nm, and the 1310 nm stands for transmission, and the 1550 nm stands for receiving.

 

cwdm

 

Single Fiber Dual Ethernet Port

With the development of business, some units put forward higher requirements, for example, we organized network for one bank, he asked us to provide two Ethernet lines to separate from. it needs mature and safe fiber optic transceiver device technology, in order to simply the cost of fiber optic devices and achieve the networks over one fiber, we try our best to save the fiber sources. Our solution is that using 10/100 m adaptive port devices, access into the Ethernet link which can reach 60 km, also keep it to support network management functions.

 

3. Gigabit fiber optic transceivers and integrated optical interface switches

The advantages of using fiber optic transceiver to connect the network, not only stable, but also it has fast speed, 100M full duplex and even 1000M duplex. For example, there is a Engineering machinery manufacturing enterprise, they use the 100M link to network at the beginning, but due to the requirements of the developments of business, we need to provide higher speed to them, fortunately, the progress of the technology provide good products for us, just gigabit fiber cable, from the appearances of fiber cable, it has no differences with 100M fiber transceivers. Yeah, the fiber optic transceiver we used can be directly pled into the original power supply unit box, which just needs to change the fiber optic transceiver and then upgrade the bandwidth from Fast to Ethernet. Otherwise, we found that the education industry prefer to use an integrated gigabit fiber interface on the switches.

How Does POE Work?

Network cables, such as Cat 5e and Cat 6, comprise eight wires arranged as four twisted pairs. In 10 and 100BASE-T Ethernet, two of these pairs are used for sending information, and these are known as the data pairs. The other two pairs are unused and are referred to as the spare pairs (Gigabit Ethernet uses all four pairs).

 

Because electrical currents flow in a loop, two conductors are required to deliver power over a cable. POE treats each pair as a single conductor, and can use either the two data pairs or the two spare pairs to carry electrical current.

 

Power over Ethernet is injected onto the cable at a voltage between 44 and 57 volts DC, and typically 48 volts is used. This relatively high voltage allows efficient power transfer along the cable, while still being low enough to be regarded as safe.

 

This voltage is safe for users, but it can still damage equipment that has not been designed to receive POE. Therefore, before a POE switch or midspan (known as a PSE, for power sourcing equipment) can enable power to a connected IP camera or other equipment (known as a PD, for powered device), it must perform a signature detection process.

 

Signature detection uses a lower voltage to detect a characteristic signature of IEEE-compatible PDs (a 25kOhm resistance). Once this signature has been detected, the PSE knows that higher voltages can be safely applied.

 

Classification follows the signature detection stage, and is an optional process. If a PD displays a classification signature, it lets the PSE know how much power it requires to operate, as one of three power classes. This means that PSEs with a limited total power budget can allocate it effectively.

 

The differences between power delivered by the PSE and power received by the PD account for power that is lost as heat in the cable. If a PD does not display a signature, it is class 0 and must be allocated the maximum 12.95 watts.

 

POE Plus equipment has a power class of 4. If a regular 802.3af POE source detects this class it will simply enable power as if it was a class 0 device. However, an 802.3at PSE will not only recognise the PD as a POE Plus device, it will also repeat the classification stage, as a signal to the PD that is connected to a power source with full POE Plus power available. (In theory the PD should also be able to request the extra power by communicating across the network link.) POE Plus PSEs can supply up to 30 watts and available device power is 25.5 watts.

 

The final stage after detection and classification of a newly connected device is to enable power: the 48V supply is connected to the cable by the PSE so the PD can operate. Once enabled, the PSE continues to monitor how much electrical current it is delivering to the PD, and will cut the power to the cable if too much, or not enough, power is drawn. This protects the PSE against overload, and ensures that POE is disconnected from the cable if the PD is unplugged.

How to save money on your homeowners insurance

The price you pay for your homeowners insurance can vary by hundreds of dollars, depending on the size of your house and your insurance company. From shopping around to making home improvements, here are some ways to save money while you adequately protect your home and assets.

Don’t skimp—but do shop around

Having homeowners insurance is undoubtedly an expense—but it is also your protection against potential disaster and financial ruin. Homeowners policy prices vary from company to company, so do some comparison shopping and get the best deal you can.
Ask friends and relatives for recommendations for insurers and then do your due diligence.
Contact the state insurance department to find out whether they make available consumer complaint ratios by company. If they do, check into the insurers you’re considering doing business with.
Check the financial health of prospective insurance companies by using ratings from independent rating agencies and consulting consumer magazines for reviews.
For price quotes, call companies directly or access information on the Internet. Your state insurance department may also provide comparisons of prices charged by major insurers.
Get quotes from at least three companies.
Don’t shop price alone. Remember, you’ll be dealing with this company in the event of an accident or other emergency. When you need to file a claim you’ll want an insurer that provides good customer service, so test that while you’re shopping, and choose a company whose representatives take the time to address your questions and concerns.

Raise your deductible

A deductible is the amount of money that you are responsible for paying toward an insured loss. The higher your deductible, the more money you can save on your premium, so if you can pay above the minimum $500 or $1,000 deductible, for example, you may reduce the cost of your homeowners policy.
If you live in a disaster-prone area, your insurance policy may have a separate deductible for damage from major disasters, so be sure you take this into account when considering whether to raise your standard homeowners deductible.

Buy your home and auto policies from the same insurer

Many companies that sell homeowners insurance also sell auto insurance and umbrella liability policies. If you buy two or more insurance policies from the same provider, you may be able to reduce your premium. To be sure you’re getting the best price, make certain any combined price from one insurer is lower than buying the coverages separately from different companies.

Make your home more disaster resistant

If you live in a disaster prone area, you will have more insurance options to choose from if you take certain preparedness steps— for example, installing storm shutters and shatterproof glass or reinforcing your roof. Older homes can be retrofitted to make them better able to withstand earthquakes. Consider modernizing your heating, plumbing and electrical systems to reduce the risk of fire and water damage. These precautions may prevent excessive damage and the related work and stress involved in rebuilding.

Do not confuse what you paid for your house with rebuilding costs

Your homeowners policy is based on the cost to rebuild your home, not its real estate value. While your house may be at risk from theft, windstorm, fire and the other perils, the land it sits on is not, so don’t include its value in deciding how much homeowners insurance to buy. If you do, you’ll pay a higher premium than you should.

Ask about discounts for home security devices

Most insurers provide discounts for security devices such as smoke detectors, burglar and fire alarm systems or dead-bolt locks. As some of these measures aren’t cheap and not every system qualifies for a discount, consult your insurance professional for recommendations.

Seek out other discounts

Types and levels of discounts vary from company to company and state to state. Ask your insurance professional about discounts that are available to you—for example, if you’re 55 years old and retired, or you modernize your plumbing or electrical systems, you may be qualify for a price break.

Look into group coverage

Does your employer administer a group insurance program? Check to see if a homeowners policy is available. In addition, professional, alumni and business groups may offer an insurance package at a reduced price. Whatever the offer, do your homework to make sure it is a better deal than you can find elsewhere.

Stay with the same insurer

If you’ve been insured with the same company for a number of years, you may receive a discount for being a long-term policyholder. But to ensure you are getting a good deal, periodically shop around to compare your premium with the prices of policies from other insurers.

Review the value of your possessions and your policy limits annually

Review your home inventory and any upgrades to your house or condo. Make sure your homeowners or renters policy covers any major purchases or additions to your home and also check that you’re not spending money for coverage you don’t need. For example, if your five-year-old fur coat is no longer worth the $5,000 you paid for it, you’ll want to reduce or cancel your floater and pocket the difference.
Another great way to save money on your homeowners policy is to take into account the cost of insurance while you’re shopping for a house and before you buy. These home buyers’ insurance guidelines provide tips on the locations, types of construction and other factors that will help keep down the cost of your coverage.