Category: Fiber Transceivers

Optical transceivers, Active Optic Cables, data center switches, and cable management in data centers.

The Benefits of Using Media Converters

Are you a network manager or a person working in IT? Have you ever had a need to extend your network infrastructure, but knew that your current cabling could not support the additional length and speeds required? If so, this is a common situation that many people find themselves in now a days. Today, we’re going to talk about fiber optic media converters and fiber switches and specifically how they can help you extend your network range, future proof your network speed, and revolutionize the way you manage your data.
So what exactly is a media converter anyway? What is a switch? Well, to start, a media converter is a simple networking device that makes it possible to connect two unlike media types, such as copper and fiber. A switch is a device that connects other devices within a network. You can also connect multiple data cables into a switch to allow communication between other networked devices. Fiber switches can manage the flow of data on a network by receiving and transmitting messages to other networked devices. Each networked device that’s connected to a switch can be identified, allowing the switch to control the flow of traffic. But before we jump into more of the details on each of these, I think it’s important for us to understand the basic differences of the network structures that are popular today.
There are really two main types of fiber optic network structures that are being used today. First is the Passive Optical Network (PON) and second is the Active Optical Network (AON). A PON is a point to point network structure that uses optical splitters to passively distribute signal. The amount of signal received is dependent on the split ratio of the hard wired splitter and is not adjustable. An AON is a point to point network structure that uses electrically powered equipment, such as a media converter or a switch, to manage signal distribution and direct signals to specific locations or subscribers. In an AON, the bandwidth allocation is completely adjustable and can be managed by software via the switch. This is the type of network structure that we are going to focus on today.
In an AON, we can use media converters to do a few things. The first, and most common application, is converting copper cable to fiber optic cable. A quick example of this would be connecting two campus buildings together. Let’s say that the length between the two buildings is over the limitations of copper cable, so you need to run fiber. How do you do it? How do you get your copper signal transferred over to fiber, without losing any of the signal integrity? Well, the simple solution is to put a media converter in both buildings and connect them together. This means, taking an RJ 45 patch cord and connecting it to the media converter via its onboard RJ 45 port. Once plugged in, you would then connect the fiber optic indoor/outdoor rated cable to its onboard duplex port. Once both are connected, you would do the same thing in the other building to make the connection complete. Problem solved.
One important thing to remember when you’re using media converters is that the data speed on the copper side is auto adjustable. This means that the RJ 45 port automatically selects the operating transmission speed depending on what the incoming speed is from the fiber optic port. The fiber optic port, however, is not adjustable. The reason it’s at a fixed speed is due to the fact that the internal laser or VCSEL (Vertical Cavity Surface Emitting Laser) in the converter can only transmit at its calibrated rate. If you have a need to adjust your optical speed rate, one way to get around this is to select a media converter or switch with a SFP (Small Form Pluggable) port. What is a SFP port? Let me explain.
The great thing about fiber optic media converters and switches is that they come in a variety of different styles and configurations. Most support all of the standard fiber optic connector types: ST, FC, SC, and LC. Typically, when you choose the LC connector, the unit will come with an open SFP port. What’s an SFP port you ask? An SFP port is an open port with a standardized footprint that accepts a removable transceiver module that’s typically designed for a duplex LC connector. An SFP module is essentially a compact pluggable transceiver. The word transceiver means that it can both transmit and receive data over a duplex fiber optic cable. These can be purchased in either single mode or multi mode wavelengths. They can transmit data various distances and speeds, depending on what your network requires. The reason why the SFP option is so beneficial to you as the network manager, is because it allows you the option to upgrade your network, down the road, without having to purchase any new active equipment. You wouldn’t need to make another capital investment. You can keep your existing equipment and speed up your system, or extend your network range, simply by swapping out your SFP modules. Just so you get an idea of how good this is, the average price on a SFP module is comparable to a Big Mac Meal for two people. The savings is significant and the convenience unbeatable. It’s a great way to future proof your network!
Alright, so now that we’ve covered some of the basics, I’ll mention one additional benefit to using active equipment. You have the ability to manage your network permissions. The great thing about using switches and media converters is that most of these have the ability to be managed remotely from a laptop. You can have full control over where your data goes and where it does not. As the network operator, this is critical. In this day and age, security is a top priority and having the ability to control your data rights is an advantage that PON does not give.
In closing, you don’t need to be an expert in fiber optics to start using media converters and switches. They’re simple, cost effective, and an easily managed solution. If you have any additional questions on this subject matter, I encourage you to reach out to an FIS sales associate today. We are available and always happy to help with all of your network needs.

What Is An SFP Module and Why Should I Use It?

In the communications industry, size and flexibility really matter. If you can pack more data transmission into a smaller package with more flexibility of options, you’re ahead of the game. Back in the early 2000’s, the introduction of the SFP (Small Form Pluggable) module and socket was a great success in bringing flexibility and expandability to everyday network test equipment. Not only is it still being utilized today, it’s become an industry standard used by manufacturers and providers all around the world.
So, what exactly is an SFP module? What does it do? Well to start, an SFP module is simply a small modular transceiver that plugs into an SFP socket on a network switch. The word transceiver means that it can both transmit and receive data. This means that the SFP module converts electrical signals to optical signals and vice versa. This is typically done over a duplex fiber optic patch cable via two LC connectors. One fiber is designated for transmit and one fiber is designated for receive, however there are certain types of SFP’s that can transmit and receive data over a single fiber by multiplexing wavelengths. We’ll discuss this more in detail later. These pluggable transceivers are used in networking devices to give the user flexibility in options and plug-and-play ease of use. There are many different types of SFP modules available today. Most can be broken down into three main categories: Transmission Speed, Range, and Compatibility.
Let’s talk about transmission speed. The most common SFP module on the market today is the 1 Gb. These are the least expensive SFP modules to purchase and by far the most popular network speed today. But with the expansion of networks and ever increasing demand for bandwidth, the 10 Gb SFP+ module is becoming more and more popular. The “+” means that the SFP module is enhanced for 10 Gb transmission. Next is the 25 Gb SFP28, which is designed for 100 Gb switches. You can achieve the 100 Gb by utilizing (4) of these SFP28 modules. The foot print for the SFP28 module is still the same as the SFP and SFP+.
Next up, we have the QSFP (Quad Small Form Pluggable) module. The QSFP module has a different footprint than the SFP and therefore is considered an evolution of the technology. The QSFP footprint is specifically designed for the multi fiber MPO optical connector. Typically, the QSFP utilizes 8 out of the 12 channels of the MPO connector for transmit and receive. The first speed available is for 4 Gb applications, which means that each channel can transmit 1 Gb of data. The next speed option is the 40 Gb QSFP+. Just like before, the “+” means that the QSFP is enhanced for each channel to handle 10 Gb of data transmission. The QSFP28 can handle 100 Gb, with 25 Gb of data on each channel.
Now that we have the basics covered on the transmission speeds, let’s talk about transmission range. If you’re familiar with SFP modules, you may have seen various abbreviations used in the descriptions to indicate the SFP’s transmission range. These abbreviations are just a quick reference guide on range. The first of these is “SX”. The SX indicates that the SFP module is transmitting a 1 Gb multi mode wavelength. The most common is the 850nm wavelength for a maximum of 550 meters. If there’s a need to extend the multi mode transmission distance, you can also choose a 1310nm wavelength for a maximum transmission distance of 2,000 meters.
The next five abbreviations are all used for single mode wavelengths. LX is used for 1310nm for distances up to 10,000 meters. The EX is also for the 1310nm wavelength but has an extended distance of 40,000 meters. The ZX abbreviation is used for the 1550nm wavelength and can transmit up to 80,000 meters. The EZX also uses the 1550nm wavelength but for maximum transmission distance of 160,000 meters. The last abbreviation is used for single fiber / bi-directional SFP modules. The BX means that you are using the 1490nm and 1310nm wavelengths to multiplex both wavelengths down one fiber. But what does it mean to multiplex wavelengths? Well, let me explain.
Wavelength Division Multiplexing (WDM) is a big topic to discuss but for the sake of time, let’s just keep it simple. SFP Modules are wavelength specific devices that convert light to an electrical signal. Basically, the idea of multiplexing is sending multiple light wavelengths down the same fiber and sorting them out at the other end. The big advantage with WDM is that you are maximizing the number of channels you have in your network. So, for example, if you have a 12 fiber cable installed in your network and you are using the standard method of 6 fibers for transmit and 6 fibers for receive, you can double your capacity by using bi-directional SFP modules and multiplexing the transmit and receive wavelengths down a single fiber. So, instead of using 6 fibers for transmit/receive, you’re utilizing all 12. Make sense?
Lastly, let’s talk about SFP compatibility. As mentioned earlier, the SFP socket and module is an industry standard used all around the world. That being said, not all SFP modules will work with all SFP sockets. Most large equipment manufacturers around the world have placed their own set of programming built into their switches. The reason they do this is to ensure the end user buys their own SFP modules and not modules from a third party. Over the past few years, a lot of third party companies have developed their own tools to program SFP modules to be compatible with the OEM. This has allowed the end user to purchase SFP modules and QSFP modules for a fraction of the original OEM cost. There are also some equipment manufacturers that adhere to the MSA (Multi Source Agreement) standard. The MSA standard is a multi-source-agreement between equipment manufacturers who came together to collaborate and standardize the form, fit, and function. So when you’re in the market for a new SFP module, the question to ask is: Do I need a MSA compatible SFP or do I need it programmed to the OEM?

Common Fiber Network Issues

Something that I take a lot of pride in, is the technical support and service that my department provides our customers on a daily basis, free of charge. I always feel a huge sense of satisfaction when the technical department can provide a solution to our customer’s questions.
Why is my fiber Ethernet link not working?
One common problem many of our customers have come to me with is “Why is my fiber Ethernet link not responding, I even get a link light but I am not getting any transmission of data?”, This old problem raised its ugly head as recently as last week. This reoccurring fiber related issue usually results from speed mismatches between the Ethernet equipment. As we know, Ethernet commonly transmits data at 10 Mbps, 100 Mbps, 1000 Mbps (1 Gig), 10 Gig and now 40 Gig. Both copper and fiber switches exist to support these speeds. As an example, a copper switch that runs at 1000 Mbps will list the port speeds as 10/100/1000. This is because copper can negotiate network speeds, meaning if a 100 Mbps device is plugged into the 10/100/1000 port, the switch can slow down the port to the 100 Mbps speed. This statement is not true when it comes to fiber. A fiber port cannot negotiate its speeds, so in this same situation the fiber equipment MUST be 1000 Mbps on each end. Typically, I see where a 1000 Mbps fiber switch port is plugged into a media converter that is rated for 100 Mbps, or vice versa, this will cause a link failure because of the speed mismatch. The reason fiber Ethernet ports do not negotiate speeds is solely due to light sources. For example, 10 Mbps fiber runs using an 850nm LED light source, 100 Mbps uses a 1300nm LED and 1000 Mbps utilizes a 850nm VCSEL (Vertical Cavity Surface Emitting Laser), so it really comes down to economics. Fiber Ethernet ports that could auto negotiate speeds would have to be built with a minimum of three light sources, theoretically tripling the price of the port. The easiest answer is to just make sure that the fiber port speed and the media converter are an exact match, as in my example from last week, the customer purchased a 1000 Mbps media converter and the problem was solved.
Why does my fusion splicer work better some days than it does on others?
Without a doubt, the single most reoccurring question the technical department receives is related to fusion splicing, or should I say the inconsistent results when splicing a fiber. The conversation always starts with the statement. “Why does my (insert manufacturer here) fusion splicer work very well some days and other days it seems to produce failing results”? One thing I stress when splicing is at a minimum, to perform an Arc Check every time you start the splicer. An arc check is calibrating the splicer against the current environmental conditions. Temperature, relative humidity and barometric pressure all contribute to the performance of a fusion splicer. When turning on a splicer, it will be performing splices according to the last time an arc check was performed. If the environment has changed, bad splices can occur. Bubbles, cracks, high attenuation and broken splices are usually a result of incorrect splice settings and can usually be corrected by running the arc check program.
A few things you need to know when performing an arc check;
• Number one: Always use Singlemode fiber when performing an arc check, even if you are splicing multimode that day, Singlemode must be used.
• Number two: If an arc check results in a NG (No Good), a second arc check must be performed, in fact several may need to be performed, (I am talking to you Denver), you must see an OK before proceeding.
• Number three: If and when you receive a NG message it is important to press the “Optimize” button, this will make the incremental changes to the splice settings.
MPO/MTP Systems – Polarity Matters
The most difficult questions we receive here have to do with the use and implementation of MPO/MTP multi-fiber cables and cassettes. Here at FIS we are constantly training our sales and support staff on the correct methods and polarities associated with these connectors. MPO/MTP connectors usually contain 8, 12, or 24 fibers in a single connection; because of the volume of fibers used, routing the fibers to the correct location can be confusing. MPO/MTP are used for space saving and also for multiple lane transmissions to achieve 40 and 100 Gig (8 fibers used for 40 gig and 20 used for 100 gig). About a month ago, I had a customer that could not get his fibers to the correct destinations using these connectors, and the solution was not easy to come to.
A little back story first; when using MPO/MTP connectors there are typically three polarity options (A, B, and C) A and B are the most commonly used and make up over 90% of our sales. Polarity B is the easiest to implement but cannot be used for Singlemode, let me explain. Polarity B cables install the connectors in a key up to key up configuration, this will flip the fibers so that transmit and receive fibers exit flipped on the other side of the cable, and this is a good thing. Typically, these cables are inserted into rack mountable cassettes that break the fiber out into individual LC connectors.
When using method B for both cables and cassettes, straight through patch cords, that we keep in stock, are used for each transmit/receive pair of LC connectors. This is an ideal situation.
When using method A cassettes and cables, this is a key up to key down solution, the problem is that it the cable does not flip the transmit and receive fibers, meaning the installer has to use standard straight through patch cords with the type A method cassettes on one side but on the opposite side MUST use flipped patch cords. This can be confusing and create installation errors. The reason Singlemode must use the A method is that the ferrules are angled and must mate opposite to each other, whereas multimode are flat ferrules and we do not have to work with an angle.
Now back to my customer’s issues a month ago, they were using method B cables and cassettes so the patch cord issue did not come in to play here. After long conversations we determined that they had installed method A mating sleeves (key up to key down) in the cassettes and not method B (key up to key up) like it should have been. By installing the wrong mating sleeves it flipped the fibers in a way that routed the fibers to the wrong ports.
When choosing a method for MPO/MTP connectors it is important to remember that the cables and the cassettes must be the same polarity/method (A or B) as well as all internal components. It can be frustrating when troubleshooting MPO/MTP issues, but ultimately it takes time to walk through the problem and experience to understand it and give your customer a solution.
It has been said that time is the price we pay for experience and I truly believe it. The FIS technical support staff has truly paid for their expertise and I implore you to take advantage of our 100+ years of combined experience to help you resolve your fiber related questions.

MPO Test Set Allows Quick Testing and Polarity Verification

MPO cables, which are typically made with ribbon or micro-distribution cable, make up a substantial share of today’s optical industry. It’s understandable because of the fact that they allow for the high speed transport of optical data in a condensed manner. This is ideal because as one can imagine, space is sold at a premium within the data center environment. In addition to providing many advantages to high-speed networks for their owners and installation technicians, MPO cable assemblies are a no-brainer for higher end bandwidth systems. When it comes down to it, they are primarily used to deliver very large amounts of sensitive data to customers consistently, making them the most reliable form of data transport with high redundancy. With all of these advantages, the 12 and even now 24 fiber MPO-style connectors are more and more becoming the preferred connector within the fiber optic industry.
With this all being said a well known challenge has been to accurately test these cables not only for dB loss but for their “polarity” configuration as well. An MPO cable’s polarity refers to the way the fibers are arranged inside the cable. There are typical polarities used within the industry; “A”, “B”, or “C” polarities. For example, Type-A polarity (straight through) is simple – fiber 1 goes to fiber 1, 2 to 2, 3 to 3 and so on. Type-B polarity (inverted) is laid out for fibers 1 to go to fiber 12, 2 to 11, 3 to 10, and so on. Type-C polarity (twisted pair) is arranged for fiber 1 goes to fiber 2, 2 to 1, 3 to 4, 4 to 3, and so on.
Traditionally, to perform attenuation (loss) testing for MPO cables the user would have to use an MPO to LC breakout cable, use a traditional power meter and test each fiber one at a time through each LC connector. Also, all polarity testing would have to be done manually as well with a visual fault locator or continuity tester. This leads to longer test durations, which means higher labor costs and an overall headache when trying to keep track of what polarity and what fiber number was for which cable.
As MPO cables have increased dramatically in popularity over the last several years. The market has evolved to produce a tester that can accommodate the growing need to test and certify these cables faster and easier. The MPO loss test sets can do all of the core functions that are demanded by the industry: Polarity check, dBm power referencing , “pass/fail” dB loss testing, continuity check, and reporting software that can certify a newly installed MPO cable. This product has cut the testing time down from several minutes to several seconds!
Once you have determined the polarity type, referencing the power meter is done essentially the same way as you would with a traditional power meter/light source set up. Attach your reference cord(s), press the zero/reference button, attach your test cable, select the polarity of the test cable and within about 10 seconds you have your entire MPO cable certified for loss and the passing results can then be stored and are ready to be organized into a report on your PC for you and the customer.
With the ability to save up to thousands of tests and define your own pass/fail thresholds, you have the flexibility to test your MPO cables under just about any situation that you or your customer needs. When it comes to reporting the results, each file slot on the meter contains results for the 12 channels (fibers) and a pass/fail mark is visible so you can easily identify and organize your test results. If you choose, you can export hundreds of files in seconds. Then the PC software program allows you to customize your header information. You can include details such as test location, date/time, operator, company, etc.
The fiber optic industry offers MPO loss test kits for singlemode as well as multimode cables that are of great value to a whole range of fiber optic technicians. The multimode set typically includes the power meter and 850nm light source with appropriate reference cables. If you are testing a large amount of cables for multimode it’s important to make sure that your multimode source is “encircled flux compliant”. Because of the nature of how multimode LED sources launch into a cable, there are other modes of light that exist in the cladding of the fiber for the first few meters which can invalidate the power reference(dBm) . This is traditionally why mandrels have been used for MM testing, however encircled flux compliant sources and/or reference cords are designed to allow for more consistent referencing, thus meaning a lower variation in insertion loss results test after test. As for the Singlemode kits, they can include a 1310nm light or a 1550nm light source. Power meters and light sources can be obtained separately as well.
When it comes to what is expected by customers and clients for MPO testing applications, it’s important to note that it isn’t just insertion loss testing and polarity verification that is needed; there are other tools that are used to maintain and properly certify these types of cables. Because insertion loss is a main concern in testing and most of the loss of the cable is coming from the connectors themselves, MPO inspection probes are gaining in popularity to ensure the MPO end face is clean. This goes hand in hand with the proper cleaning consumables to keep the 12 -24 fiber end faces clean and defect free.
Most MPO test sets today work in conjunction with a MPO capable visual inspection probe with pass/fail software that adheres to the IEC industry standards. This ensures the customer that the cables were inspected and passed when installed and tested. The images can be uploaded into a report in the same fashion as typical single fiber images can be.
As far as cleaning goes, there is a whole range of cleaners one can use. The most effective are the “push-click” style cleaning pens; which can clean both male and female MPO connectors as well as into mating sleeve bulkheads. There are also gel pads that the user will press the connector into and when the connector is removed from the gel pad any debris that was on the connector endface remains in the gel, leaving the endface clean.
Typical MPO test kits would include: MPO power meter, MPO light source(s), reference cords, mating sleeves, A.C. power adapters, reporting software, etc. Separate additional accessories to assist in maintenance: MPO connector push-style cleaner, MPO gender change tool, MPO/LC breakout cable, extra reference cords and mating sleeves.
As you can see the MPO style connector isn’t going anywhere and today the industry offers options that allow technicians to properly verify, test, and certify all aspects of their MPO cable assemblies. Whether it be polarity or continuity verification, insertion loss testing, or end face inspection, the tools exist to confidently certify these assemblies built for high density and high bandwidth applications.

Advantages of Jetting Fiber Optic Cable Over Traditional Pulling

What are the advantages of blowing or jetting fiber optic cable vs. traditional pulling?
Pulling and blowing are the two primary fiber installation methods. But each of these techniques can impact the longevity, performance, and return on investment (ROI) of a fiber optic network. If you take into account the fragility of glass or fused silica during installation, distance to be covered, efficiency, and costs, you may see that jetting (blowing) offers many advantages over traditional cable-pulling techniques.
An Overview of Fiber Optic Cable Installation Methods
• Pulling: It involves pulling the fiber optic cable through pre-installed underground or aerial ducts. You can pull the cable manually or using a reeling machine. You’ll also need a pulling tape to haul the cable while measuring the distance covered.
• Blowing: With this technique, high-speed air pressure pushes fiber optic cables through standard ductwork or microduct systems.
Here are the reasons why cable jetting is superior to traditional pulling methods:
Minimal Risk of Tension Damage
Each brand of optical fiber cable has a maximum tensile strength. But in pulling, there’s a risk of straining the cable beyond its limit, which can compromise the fiber’s performance and cut its service life. Unchecked resistance forces, such as friction, on the sidewalls of cables and ducts, can also cause damage during a “pulling” installation.
In contrast, jetting involves little or no pulling, which significantly minimizes strain on the fiber optic cable. You can not only configure the system’s hydraulic pack or air-compressing equipment to control airflow inside the duct but also monitor the conduit and fiber to minimize damage.
To minimize friction during cable jetting, consider applying lubricants meant for the method. Ducts with low-friction interior walls may also help.
Suitability for Long-Haul Fiber Optic Networks
Pulling isn’t the best option for placing outside plant (OSP) fiber optic cable. With the technique, there’s always a high possibility of pulling the cable into conduit bends. And as bend angles continue to accumulate, it becomes increasingly difficult to optimize pull length. The bad news is that ducts for cross-country fiber optic networks can have many bends.
As such, pulling is ideal for short-distance fiber optic cable deployment. Distance will vary from one manufacturer to another and cable jacket material plays a role too.
With high air speed blowing fiber optic installation, however, conduit bends and undulations aren’t as much of an issue as they are with traditional cable-pulling techniques. The blowing force doesn’t pull the cable into a duct bend. It instead pushes it smoothly around every turn or curve.
In other words, the duct route geometry doesn’t impact installation distance in this case. Consequently, air-assisted installation lets you place fiber optic cable thousands of feet between jetting sites. That’s why it’s suitable for OSP fiber deployments, for example, telecommunication, CATV, and internet networks.
Reduced Costs
Cable jetting equipment and ductwork may be initially expensive. But you can amortize these upfront costs depending on current needs, and your initial investment may pay off in future savings on upgrades. For example, you don’t have to invest in redundant higher fiber counts when you can cheaply upgrade capacity in tandem with changing requirements.
Likewise, “pulling” is more labor-intensive than the blowing method. The technique involves more equipment movement, and it may require the positioning of placing tools at intermediate points and both ends of long OSP runs. Additional workers and extra equipment translate to higher installation costs. Cable jetting requires fewer cabling technicians, however.
Keep in mind that air-assisted optical fiber installation minimizes the number of splices needed. Cables installed this way don’t usually require “figure-eight” looping to prevent twisting every time duct changes direction. Since the approach has fewer intermediate-assist placement operations, it limits the number of handholes and other access points required along the cabling route.
Suitability for Microduct Installation
Jetting is very effective in pushing fiber optic cable through microducts. With the blowing method, you can place microduct cable in continuous lengths. The technique is most suitable for modern optical fiber cables that tend to contain bare fibers, and sometimes reduced cladding diameters, both of which contribute to decreased outer cable diameters.
The thinner a fiber optic cable is, the larger the number of fibers you can place in specific innerduct. As such, jetting is the best installation technique when you wish to make the most of the available duct capacity. It also allows you to work with small but flexible fibers that go through multiple microduct twists and turns over long distances with near-zero bend losses.
Additionally, when setting up microducts for fiber optic cable jetting, you may include redundant ductwork to accommodate new fiber in the future as required. This way, you avoid the unnecessary costs of placing dark fiber, which may become obsolete sooner than anticipated.
Appropriate for Removal of Old Fiber
Pulled fiber optic cable may be difficult to remove when no longer needed. The presence of old and unwanted cables in mission-critical physical pathways may limit your ability to optimize your optical network capacity or even upgrade to higher-performance fibers.
But after installing optical fiber by cable jetting, you may easily remove it by the same approach when necessary. You may be able to reuse the removed fiber optic cable since the removal process is gentle enough to minimize or avoid damage.
Quick Installation
Cable jetting is faster than the “pulling” method. The pushing device can move fiber optic cable at speeds of 350 feet per minute or higher. With the air-jetting technique, you can quickly push cables through pre-installed innerduct or underground ductwork. But in most cases, you can only pull fiber at a rate of 100-200 feet per minute, or even slower.
Less Disruption
Choose cable jetting to upgrade your optical fiber with minimal interruption to ongoing workflows or operations. The cable-pulling approach is more disruptive.

Choosing the Right Fiber Optic Cable

There are so many fiber optic cable options available that one might wonder where to start. This article will set you on the right path in the decision process. Let’s begin by focusing on the broad categories of fiber optic cable. Below you can make “either/or” decisions. A handy reference chart that summarizes key cable features can be found below.
Multimode or Single Mode?
Multimode Cable – Applications: Multimode fiber is used to transport high volumes of data over relatively short distances (compared to single mode fiber). Common applications include Data Centers and other Local Area Network (LAN) applications. Note that multimode distance capabilities have increased over the years. Multimode fiber cable now offers an economical alternative to single mode cable for certain applications. Design: Multimode cable has a relatively large core (either 50 or 62.5µm) that enables multiple streams of data to be transported simultaneously.
Single Mode Cable – Applications: Telcos and CATV companies use single mode cable to transport signals over long distances. Business campuses and other institutions also use single mode cable for longer cable runs, such as links between buildings. Design: The core diameter of single mode fiber is so small (9µm) that it permits only one mode of light to pass through it at any given time. This characteristic reduces attenuation and enables light to be transmitted over great distances. While the purchase price of single mode cable is less than multimode cable in general, single mode transceivers and network interfaces are generally more expensive than those used for multimode systems.
Simplex or Duplex?
Applications: Simplex and Duplex cables are typically used for fiber optic patch cables and desktop installations that don’t require a high fiber count. Design: Simplex cables contain a single 900µm coated fiber or a combination of a 900µm coated fiber surrounded by an aramid yarn strength member with an outer jacket diameter varying between 3, 2, 1.8 and 1.6mm. Duplex cables contain two 900µm coated fibers surrounded by an aramid yarn strength member with an outer jacket diameter varying from 3, 2, 1.6 and 1.2mm.
Loose Tube or Tight Buffer?
Loose Tube Cable: Applications: Loose tube cable is ideal for use in long distance outside plant applications that require a high fiber count. The cable is designed to withstand harsh outdoor environments; the cable’s unjacketed fibers are free to expand and contract with temperature changes. Design: Fibers within loose tube cables are surrounded by a water blocking component (either gel or a dry water-blocking material). Although loose tube cables are engineered to withstand damp outdoor environments, they are not designed to be submerged in water, but can come in contact with water. Terminating Loose Tube Fibers – The fibers within the gel-filled tubes of the cable have a very thin acrylate coating which is 250µm in diameter. Before terminating, the fibers must be put into small plastic tubes (called a breakout kit or box). The tubes protect the thin fibers and make them easier to handle when terminating and connecting to network equipment.
Tight Buffer Cable: Applications: Tight buffer cable is typically used indoors. A tight buffer (cable jacket) encapsulates each fiber. The 900 micron buffer enables the fibers to be directly terminated without requiring a breakout kit, which saves substantial time. These cables do not typically provide protection from water migration and do not isolate fibers well from the expansion and contraction of other materials due to temperature extremes. Tight-buffered cables, often called premise or distribution cables, are ideally suited for indoor-cable runs. Design: Tight buffer cables have two protective coatings; a 900 micron PVC jacket and 250 micron acrylate coating, all encased in an outer PVC jacket.
Distribution or Breakout?
Distribution Cable: Applications: Distribution cable is ideal for networks that terminate multiple fibers at a common location, such as a patch panel or communications closet. Fibers within a distribution cable have their own 900 micron individual cable jackets. This space-saving feature enables up to 144 fibers to be bundled within the cable. Fibers in a “Micro Distribution” cable do not have the 900 micron tight buffered PVC jacket, instead they contain color coded 250 micron acrylate coated fibers. Because of the decreased diameter of the individual fibers in the cable, a micro distribution cable may contain up to 432 or more fibers. A disadvantage of micro distribution cable is that the unjacketed fibers require the use of a breakout kit for termination. Design – Distribution cable contains a number of 250µm – 900µm fibers that are color-coded for easy identification. The cable includes an aramid yarn strength member and a thick outer jacket that provides protection and strength during cable installation. If required, the cables can be purchased with interlocking armor.
Breakout Cable: Applications: Breakout cable is ideal for applications where fibers are connected directly to equipment, including local hubs. Also, the robust design of breakout cable makes it well suited for use as drop cables. Design – Breakout cable differs from distribution cable in that each of the fibers in a breakout cable is 900 micron tight buffered and surrounded by aramid yarn all encased in a 2mm or 3mm PVC jacket. Then all of these 2 or 3mm jacketed fibers are encased in an outer jacket. This additional jacketing can save substantial time and installation cost, especially if the fibers are being terminated with connectors. One disadvantage of breakout cable is that the fiber jackets take up room within the cable, so breakout cable cannot contain as many fibers as distribution cable. Fiber counts for breakout cable are typically 2-24 fibers (maximum is 48 fibers).