Eight Factors Influencing Your Fiber Optic Installation Bills

Nowadays more than one third of the popularity have access to the internet. Large enterprises already use the high-capacity fiber-optic access networks, and small- or medium-sized businesses also want to relieve the bottleneck of the copper-based access network and benefit from the fiber-based access network. Nonetheless, costs is one of the factors that small business would take into account. In fact, the cost of large-scale fiber optic deployments depends on a wide range of factors, including redundancy and survivability need, access to the closest fiber line, labor cost, Aerial vs. Underground, and the fiber maintenance cost. The following article concludes several factors that will have great impact on the costs of building a fiber optic network.

Figure 1 shows the layout of the fiber optic network in an office building.

Reminder:

Every building is situated differently, has different surroundings, different neighbors, and different physical dynamics influencing access to fiber lines, how much you’d have to spend on installation will be determined according to the specifics situation. Therefore, the factors listed below can not fit every situation. And we will not present the available materials that are likely to be used in you network as each installation requires its own assessment to determine final fiber optic network.

Redundancy and Survivability Needed

In a network designed with redundancy in mind, each portion of the network is constructed as part of a ring and economical construction is possible. On the other hand, when redundancy is constructed after the fact, it requires a custom cable pathway, usually doubling (or more) the construction cost.

Recently nearly 99 percent of the network will need two redundant physical paths from the network to its location, along with an electronic infrastructure to accommodate failure of a fiber route or an electronic component, and backup power of sufficient duration. And it also need to provide a 24-hour network operations center, a fiber repair crew, intrusion detection, and backup management and recovery facilities.

If network users do not require this level of availability, the network operator should determine their actual current and future requirements, and which subset of survivability and redundancy tools are needed. Ideally, any needs for physical redundancy will be included in the initial project design.

Labor Costs

Although the fiber equipment costs have fallen, skilled labor costs have risen. So how can operators limit those high labor costs and still deploy a quality fiber network that can handle the bandwidth needs of today’s subscribers?

Labor typically forms the majority of the cost of construction—approximately 50 to 80 percent. Therefore the quantity of fiber strands and cables, a materials cost, is typically a secondary consideration. Labor costs are highly variable. For example, poor economic conditions may lead construction companies to reduce their fees, while mobilization of contractors may increase their bid rates if there is suddenly high demand for immediate construction. In general, large-scale ventures have an advantage in managing costs, because construction companies feel comfortable offering lower rates when they expect to profit from the volume and duration of a project.

Ability to Reuse Existing Infrastructure

Reuse the existing infrastructure is not only a cost-saving solution, but an eco-friendly option for overall users. There are a number of options for using existing cable infrastructure. For example, if there is sufficient space in the existing conduit, then you can take advantage of conduit by adding new capacity to your building, which will make your installation substantially simpler and cheaper. Furthermore, whether the existing conduit already lead straight up into your building, or it is configured through twists and turns will have a major impact on the costs of its installation. That’s it, winding paths are trickier than straight cables.

Let’s solve a problem in arithmetic. The cost of a 6-count fiber cable is $2,000 per mile, while an 864-count cable is $50,000 per mile, implying a marginal cost of approximately $50 per fiber per mile. Actual costs for fiber purchase or lease, of course, reflect market costs and depend on the total availability of fiber over the route—and are thus, typically, considerably higher; however, fiber lease or purchase may be a serious consideration over routes where construction is difficult or costly and considerable fiber has already been installed.

Aerial vs. Underground

Typical construction is a mixture of aerial and underground techniques, in part because aerial construction also is more vulnerable to extreme weather, particularly in wooded areas and areas with frequent ice and high winds. And another reason is that aerial construction may be more expensive when poles are crowded or when the utility pole owner charges high rates for access. Worst-case costs can be $100,000 per mile (which usually would lead a network owner to build underground or over another route).

Underground construction also has a wide cost range. In areas where restoration is not important and long continuous runs are possible, “plowing” the fiber into the ground is an inexpensive option—approximately $70,000 per mile. For more detailed information about aerial and underground construction, please see an article entitled “Whether to Go for Aerial or Underground Deployment”.

Based on the estimated percentage of aerial and underground plant we identified in our field survey, we estimate that the difference between aerial and underground construction in Santa Cruz is more than $80,000 per mile, as shown in Table 2.

Table 2: comparison of estimated aerial and underground construction costs.

Cable Management

Of cause, wire management is the most important part of any installation, especially for data communication. For better cable management in server room or the data center, IT racks, fiber enclosures and patch panels should be used. To determine what type of panels you need, take into consideration the space that will be utilized for the network. If you are installing inside of a closet or other cramped quarters and need low density, wall mountable panel is the best choice because it does not take up a lot of room. If racks are already in place, or if there is enough room to install them, rack-mount tray is the best choice because it is sturdy and easy to access. Keep in mind that rack-mount tray does not protect against environmental conditions.

Figure 3 shows the required equipment for better cable management.

Open frame racks are suggested for this server room, which can provide more flexible cabling environment. The using of fiber enclosure and adapter panels should depend on the fiber count.

The Location of Your Network

The single greatest determining factor not only to how much installation costs, but also how difficult it is to accomplish. Is fiber local or close to your office building? Or do you have to cross a state highway to extend fiber into your site? The nature of the physical terrain that the fiber needs to traverse to reach your building becomes significant. If you have to cross a state highway to bring the nearest fiber to your building, overcoming that obstacle will significantly impact the overall costs. Special use areas such as historical sites can often cause a problem for bringing fiber directly to your building. If there are any of these sites nearby your location, they could potentially impact the costs of fiber installation, depending on the route fiber needs to take to your facility.

And when the fiber is brought to your building, do you have a telecommunications room with the necessary space for installation already available? If so, that will streamline your installation costs, and ensure connectivity continuity once the installation is complete. As you may be gathering, every potential wrinkle in the process of installing fiber has the potential to make it more complicated, and everything that does in fact represent a hurdle has the potential to make the final charges more costly.

Power for Fiber Technology

How easily is sufficient power for fiber accessible from your telecommunications room? If there is ample power available, or if an emergency generator can be used to insure up-time of activated service, then you will save in fees that would require the introduction of additional power capabilities.

Fiber Maintenance Costs

Fiber optic cable is resilient compared to copper cable and coaxial TV cable. The fiber itself does not corrode, and fiber cable installed over 20 years ago is still in good condition. However, fiber can be vulnerable to accidental cuts by other construction, traffic accidents, and severe weather. In other networks of this size, we have seen approximately 80 outages per 1,000 miles of plant per year.

The fiber optic redundancy from the hubs to the FDCs in the backbone network will facilitate restoring network outages while repair of the fiber optic plant is taking place. Depending on the operational and business models, you might be responsible for adds, moves, and changes associated with the network as well as standard plant maintenance. These items may include:

• Adding and/or changing patching and optical splitter configurations at hubs;
• Extending optical taps and laterals to new buildings or developments;
• Extending access to the FTTx network to other service providers;
• Relocating fiber paths due to changes such as the widening of roadways;
• Participating in the moving of utilities due to pole replacement projects;
• Tree trimming along the aerial fiber optic path.

Conclusion

If you are still with us, and concerns about the cost of the installing a fiber optic network, please do not feel hesitate to contact FS.COM for a free consultation. We’ll be happy to provide you with the perfect solutions that meets your specific needs, and clarifies all the above factors that contribute to the bottom line. We offer a full range of enterprise network solutions including the 10G/40G switches, optical transceivers, high-density fiber optic cables, etc.

How to Choose the Fiber Optical Solution for Cisco Catalyst 4500-X Series Switch?

We can’t deny the fact that Cisco is one of the most important developers of network devices in the world. They supply a full range of switches including the Nexus, ME, Meraki, Blade, and Catalyst lines. Each of them is designed for unique applications, for example, Catalyst Switches is made for Campus Networks and Nexus Switches for Data Centers. Catalyst 4500-X series switch as one of the intriguing new switch of the catalyst lines, is a cost-effective, fixed aggregation for campus LAN network that brings in 10GbE uplinks. Featured with small size, high scale, this switch is warmly welcomed by overall users. Today’s article will provide some detailed information about this switch, and some advice about how to choose the right optical solutions.

Features of Catalyst 4500-X Series

Catalyst 4500-X switch is available in four versions: 40-port, 32-port, 16-port, and 8-port. Cisco offers seven different chassis of the series, namely Catalyst 4500X-16, Catalyst 4500X-24-IPB, Catalyst 4500X-24-ES, Catalyst 4500X-32, Catalyst 4500X-40, Catalyst 4500X-F-16, Catalyst 4500X-F-32. Remember to pick the right one that meets your needs. Compared with the Catalyst 3850 switch (also known as the 3750-X successor), we can clearly see its advantages, which has been displayed in the below part.

• Cisco Digital Network Architecture

Only Cisco delivers a digital-ready approach that starts at the edge and extends to where applications reside.

• Platform scalability

The Cisco 4500 offers up to 800 Gbps of switching capacity. It can scale up to 1.6-Tbps capacity and provides resiliency with Virtual Switching System (VSS). VSS refers to a method that can combine two physical switches into one logical switch to achieve physical redundancy, spanning free blocking elimination and increased bandwidth. That means any two Cisco catalyst 4500-X series switch can be pooled together into a VSS.

• High availability

Simplify network deployment and management with easy virtual networks (EVN). The 4500-X also reduces energy costs. Furthermore, device resiliency features such as redundant hot-swappable fans, power supplies, and AC to DC failover and vice versa remove single points of failure in the network.

• Application monitoring

Get enhanced application monitoring through Flexible NetFlow and 8 ports of line rate bidirectional Switched Port Analyzer (SPAN)/Remote Switched Port Analyzer (RSPAN). Cisco IOS XE Software provides the ability to host third-party applications.

• Security

Enhance security with support for Cisco TrustSec and Flexible NetFlow technologies.

• Simplified operations

The 4500-X offers support for Smart Install Director. Customers gain a single point of management for zero-touch deployment of new switches and stacks in campus and branch networks.

How to Choose the Optical Solutions for Catalyst 4500-X?

As noted before, the 4500-X ports support both SFP+ 10GbE optics and 1GbE modules. No matter what type of Catalyst 4500-X series switch you use, you will face the same problem of how to select the right one. The following image shows a 32-port chassis catalyst 4500-X series switch (front view).

1—UID LED and switch combination
2—STATUS LED
3—PS1 LED
4—PS2 LED
5—FAN LED
6—USB ports
7—The 16 port version of the chassis does not have the block of 16 ports on the right side of the front panel.
8—Port status LEDs
9—8-port uplink module (Included as part of the WS-C4500X-24ES and WS-C4500X-40ES chassis; available as an optional upgrade on the other Catalyst 4500-X series chassis)

As noted before, each Ethernet port requires either an SFP or SFP+ transceiver be installed to operate. The common used pluggable modules includes the three types—copper cable with RJ45 connector, direct attached cable and the pluggable transceiver module with the fiber patch cable. Before making the move, it is necessary for us to review the basic knowledge of the fiber optic transceiver (SFP and SFP+), DAC cables and fiber patch cable that are available for Catalyst 4500-X switch.

Cisco SFP and SFP+ Optical Transceivers

Fiber optic transceiver is a device that comprises of both a transmitter and receiver of analog or digital signals. It is usually inserted into optical devices like switch, router or network interface cards which provide one or more transceiver module slot. Cisco SFP modules and SFP+ optical transceivers are available in different standard. The following table has listed some of them, which you might want to have a look at it.

Figure 4 shows available Cisco SFPs for Catalyst 4500-X Series Switch

Figure 5 shows available Cisco SFP+ for Catalyst 4500-X Series Switch

Fiber Optic Patch Cables

Fiber Patch Cable, also known as fiber jumper or fiber optic patch cord is designed to interconnect or cross connect fiber networks within structured cabling systems. According to fiber cable mode, cable structure or connector types etc., fiber patch cable can be divided into different types. But remember that your fiber patch cables should always be compliant with the existing optical transceivers. For instance, LC LC multimode patch cord can be only used on the multimode optical transceivers (1000BASE-SR SFP or 10GBASE-SR SFP+). If you know nothing about this, it is advisable for you to talk with your supplier.

SFP+ Cables

SFP+ cables is the cost-effective solution for users in telecom field. It usually comes in DAC and AOC cable types. This fiber optical solution is suitable for short link applications within racks and across adjacent racks. Compared with the optical transceivers based system, it is inexpensive and more convenient. The available SFP+ cables are listed in the below chart.

Fiberstore Fiber Optic Transceivers & Fiber Patch Cable Solutions

To sum up, in order to find the perfect fiber optic solution for your network, firstly you need to understand your needs, and consult with your vendors, then purchase all the available equipment within the budget. All the above optical devices like the copper cable, fiber optic cables, SFP & SFP+, and SFP+ DAC cables are provided at Fiberstore. You don’t need to worry about the compatibility issue because all of our products are tested in our test center before shipping. Furthermore, they are even backed by a lifetime warranty. Custom service is also available to fit your specific requirement.

Do You Know How Fast Your Fiber Optic Internet Can Be?

It is no secret that the technology is continually evolving, so does the demand for consistent and accessible information and entertainment. From the old 56 kbqs crawl of dial-up, to the early 1 Mbqs copper connections and all the way to the existing popular 1 Gbqs, 10 Gbqs/40 Gbqs fiber optic connections, we’ve gone through a drastic improvement to maintain a stronger signal, a better connection, a faster speed. It seems that the intricacies of internet can get complicated, so how do you draw the line with your internet consumption and speed demands? So in this blog post, we explain how fiber optic works, why cause the boom in fiber optic speed and how fast fiber optic internet can be.

How Does an Fiber Glass Function in the Internet?

We know that fiber optic cable works like a bridge between the consumer and internet supplier. But how does this process actually work? To put it simply, fiber cable works by sending data as pulses of light through a glass fiber. At one end of the fiber, a laser or LED transmits data as light. At the other end of the cable, the light will be interpreted into data by the light-sensitive receptors.

If the above explanation is not clear to you, then here comes the more vivid description. Fiber optic cables consists of a strand of fiber glass wrapped in a protective jacket called cladding. Owing to the total internal reflection, light can go from one end of the core to the other end without ever changing its wavelength. More detailed information, please see an article entitled “A Quick Lesson In Fiber Optics”.

Fiber Optic Cable Types: Single-mode and Multimode Fiber

Single-mode and multimode fibers are the two broad categories of fiber core that can affect how light can travel through the cable. In single-mode fiber optic system, there is only one pathway or mode that light can travel along. While in multimode fiber optic system, seen in the below image, there are multiple pathways just like a circus funhouse with beams of light traveling along a variety of pathways through the core.

Theoretical, if you have one light beam traveling in both the single-mode and multimode fibers, the straight line beam of the single-mode fibers will reach its destination first. This difference is usually caused by the modal dispersion, which explain the reason why we often use the single-mode fibers for longer reach application.

WDM and Dark Fibers

The advent of WDM (wavelength division multiplexing) in the mod-2000s as a great breakthrough in fiber optics as it allows multiple channels to be carried at the same tine on a single fiber optic cable. There are all together CWDM and DWDM systems, CWDM or course WDM is the initial implement that allows 4 and 8 wavelengths, such as the Ethernet LX-4 standard which allowed a cable to carry four 3.125 Gbit/s data channels, resulting in 10Gbit/s aggregate.

In DWDM (Dense WDM) system, even though it is much more expensive, it can handle up to 160 data channels expanding basic a 10 Gbit/s system over a single fiber pair to over 1.6 Tbit/s.

Figure 2 display different wavelengths can be bundled together in the same mode.

In terms of the new concept—dark fiber, it represents the unused cable laid in the network as space capacity, carrying high amounts of data at high speeds over hundreds of miles. Simply put, with DWDM, dark fiber network can easily increase bandwidth and allow more data to be send via optical fibers. And as the price reduces, dark fibers are gradually becoming more popular than ever.

How Do You Find out What Speed You Need?

This seems to be a noob question. As you can simply use the speed testing websites to discover the speed of your internet connection. And tracking the aspects of your internet use can give a better ideal of what speed you have and the speed that is optimal for you. What I want to express here is the common mistakes you will make.

It is not always the ISP’s fault, if your speeds are slower than what you expect. Several factors might have great impact on the accuracy of speeds. For example, the types of the hardware you have, the age/types of the line you have, and how busy the internet is at all time.

To find what speed you need depends on several different elements. How you plan to use the Internet, how many devices you have in your home, and how fast you expect to be connected are just a few factors that influence which speed is right for you. For office network, network speed under gigabit Ethernet is not sufficient.

Remember, speed is a maximum level, not a guaranteed one. As your desire for a faster connection increases, be sure you have the Internet speed that will exceed your technological needs!

The Next Steps for Fiber Optics

The modern commercial fiber optic system enjoys it stay in the Gigabit Ethernet speed. But we can look forward to the increases in the range of gigabits per second down speed, perhaps even breaking into the terabit range, in the not so distant future.

Introduction to Several Cable Ties

Owing to its low cost and ease of use, cables ties are ubiquitous in a wide range of telecom applications. Generally, cable ties, zip ties, or tie wraps are designed to hold items together, primarily the electric cables or wires. It is treated as a type of fastener. There are multiple types of cable ties available on the market today, such as nylon cable ties, Stainless Steel cable ties, and Velcro cable ties, etc. And each of them has their own features. So this article will introduce three common cable ties for you to select which cable ties suitable for the wire management.

Nylon Cable Ties

The common zip ties, normally made of nylon, has a flexible tap section with teeth that engage with a pawl in the head to form a ratchet so that as the free end of the tape section is pulled the tie-wrap tightens and does not come undone. The Nylon material possesses an outstanding balance of properties, combined strength, moderate stiffness, high service temperature, and a high level of toughness.

Nylon cable ties are particularly resistant to repeated impact. They have a low coefficient of friction, and excellent abrasion resistance. But they should be stored in cool dry areas, out of direct sunlight, and sealed in the original packaging material. These measures will extend cable tie performance levels indefinitely. Nylon cable ties can be broadly divided into several cable ties: Colored Cable Ties, ID Marker Ties, Eyelet Cable Ties, and Releasable Cable Ties. An article entitled “Nylon, Velcro and Stainless Steel Cable Ties” has provided some detailed information about these cable ties.

Velcro Cable Ties

Velcro Cable Ties is made of soft hook and loop material, also known as hook and loop cable ties. They deliver reliability by protecting against over-tension of high-performance fiber and copper cables. These ties are adjustable, releasable, and reusable to effectively support frequent moves, adds, and changes (MACs). Moreover, a wide range of designs, sizes and colors provide flexibility and an aesthetically pleasing appearance. The key benefits of velcro cable ties are reliability, scalability and aesthetics. Velcro cable ties are very useful for computer and other data-cables as they will not crush the cables and cause damage.

Stainless Steel Cable Ties

The stainless steel cable ties either naked or coated with a rugged plastic, cater for exterior application and hazardous environments. This type of cable ties are made of stainless steel, which makes them much stronger and able to achieve a tensile strength of up to 400 pounds or more. Differ from plastic cable ties, you don’t need to pull this cable tie to a tight close but through a through a self-locking mechanism. This mechanism can stand alone or be part of a ball lock system. What this locking mechanism does is add strength to the tie and ensure that it doesn’t wear down or corrode when the temperatures get too hot or cold. The best part about this locking device is that you don’t need much strength to feed the tie through. Stainless steel cable ties are ideal for applications that require a high-level of protection against corrosion and environmental conditions, which may cause typical nylon cable ties to disintegrate.

At the end of this article, one misunderstanding about cable ties needs to be explained. Cable ties, especially the plastic cable ties are generally viewed as single-use devices; they are typically cut off rather than loosened and reused. However, if a closed loop needs to be opened again, rather than destroying the cable tie by cutting, it may be possible to release the ratchet from the rack. While some cable ties are designed for reuse with a tab that releases the ratchet, in most cases a sewing needle or similar object will need to be interposed between the ratchet and the rack. Ties reused in this way will be weaker than new ones.

Conclusion

To sum up, this article has briefly introduced three cable ties. Each should be suitable for the unique applications. No matter what your installation requires, FS.COM is sure to have the exact zip or cable tie that you need. Please don’t feel hesitate to contact us.

MTP/MPO Fiber Cable and its Application in 40G Network

As the request for greater bandwidth and higher-density fiber optic connections within data centers continues, these requirements must be met by choosing the right type of connectivity. MPO/MTP fiber cable is specially designed for applications for all networking and device needs like 40G modules. It uses a high-density multi-fiber connector system built around precision molded MT ferrule, which are available in UPC and APC polish. It supports both multimode and single-mode applications, and optional lengths available. There are two main MTP/MPO cables types: MPO/MTP trunk cables and MPO/MTP harnesses cables. The following article will have a brief introduction to them individually.

MPO/MTP Standard Trunk Cables

Available in 12, 24, 48 and 72 fibers, MPO/MTP trunk cables work as a permanent link that connects MPO/MTP modules to each other. These cables are used to facilitate rapid deployment of high density backbone cabling in data centers and other high fiber environments reducing network installation or reconfiguration. A 72-fiber MPO/MTP trunk cable (see in the below image) can be terminated with 6 MPO/MTP connectors which are manufactured specifically for multi-fiber loose tube or ribbon cable. The MPO/MTP Trunk cable is designed for Data Center Applications.

These cables can interconnect cassettes, panels or ruggedized MPO fan-outs, allowing for the flexibility in case any decision is made to change the connector style in the patch panels, new cassettes can be installed with the new connector style on the cross-connect side of the patch panel without having to change the connector on the cable trunk.

FS.COM offer single-mode (OS2) and multimode (10G OM3, 10G OM4) MPO/MTP Cable. Single-mode MPO/MTP cable is primarily used for applications involving extensive distances, 10G MPO/MTP cable provide 10G data transfer speeds in high bandwidth applications and they are 5 times faster than standard 50um fiber cable. Work with both VCSEL laser and LED sources, that means, the MTP/MPO trunk cables also provide 40G/100G MPO/MTP trunk cable.

MPO/MTP Harnesses Cables

The MPO/MTP Harnesses cable is MPO/MTP on one end, with single-fiber connectors on another end, single-fiber connector interface available in SC, ST, LC, MTRJ in forms of simplex or duplex channeling. It provides a reliable, cost-effective cabling system for migrating from legacy 10G to higher speed 40G/100GbE. They are suitable for many device needs like 100G modules, including CFP, CFP2 and CFP4 series. MPO/MTP Harnesses cable are available in SM (OS2), MM (OM3/OM4). You could select the suitable fiber according to your own needs with the selection of 12/24/72 fiber cores. The following picture shows the OS2 Fiber Optic Harness Cable.

The MPO/MTP harnesses cable application for data centers requiring quick infrastructure deployment with extended reach that want to maintain bandwidth throughout the infrastructure, its design cater for up-scaling needs and future technologies growth, it’s the best solution, which covers all fiber optic cabling needs in all areas of Data Center.

High-density MTP/MPO Cables for 40G Connection

IEEE 802.3ba 40 Ethernet Standard was ratified in June 2010. This standard specifies MPO connectors for standard-length MMF connectivity. MMF employs parallel optics using MPO interconnects for 40GbE transmission. More specifically, 40G is implemented using eight of the twelve fibers in a MPO connector. Four of these eight fibers are used to transmit while the other four are used to receive. Each Tx/Rx pair is operating at 10G.

Figure 1 shows a Type B MTP female trunk cables for 40GBASE SR4 QSFP+ and multi-fiber migration networks.

Figure 2 shows how to extend your Cisco Nexus 10GBASE-LR networks up to 40G with MTP cable and 4x10GBASE-LR SFP+ transceiver for your high speed data center solution. The 4x 10GBASE-LR SFP+ transceivers interconnection with 1x 40GBASE-LR QSFP+ transceivers (QSFP-40GE-LR4) by one MTP to 4LC harness cable directly.

Fiberstore MPO-based fiber cabling solutions provide a fast, simple and economical way for 40G applications. Certainly, 40G fiber cabling solutions are not only limited to MPO/MTP fiber cables. QSFP cables, especially direct attach copper cables are also recommended. 40G direct attach cable provides a cost-effective solution for high-density network connectivity. You can see the detailed information in an article entitled “40G Direct Attach Cable (DAC) Cables Overview”.

Conclusion

To sum up, MPO/MTP cabling have proven to be an excellent solution for delivering 10G, 40G and 100G transmission, especially within a data center environment. It provides a flexible, high density option for quickly connecting services. FS.COM offers various high-density MPO/MTP fiber optic cables, trunk and harness versions, patch cords, and cassette module. The MPO/MTP fiber cables are tested with guaranteed quality, and they can be installed easily, which saves time and money. Besides MPO/MTP cables, other cables are also supplied, like LC to ST fiber cable, LC SC cable, SC SC fiber cable, and so on.

How Far Can You Bend Your Fiber?

We know that stress and overstrain is a major enemy of the fiber’s lifespan, so cable installers must ensure that during the installation, fiber cables would not suffer from undesirable stretching or bending. Pulling, pushing and blowing are the three techniques used in wire management, which usually cause minor installation strains even for a seasoned installer. It is unavoidable, but fiber optic cables made of glasses have a limitation of bending ratio or tight diameter. If it do not exceed the certain diameter, the fiber will function well. Therefore it is essential for us to know how far cables can be bent. In fact, the maximum transmission distance of the fiber optic cable depends on the aspects like bend radius, tensile strength and usable duct space, which will be clearer illustrated in the following article.

Bend Radius

Bend radius is the curvature an optical fiber can bend without damage or shortening its lifespan via kinking. The smaller the rated bend radius, the more flexible the fiber. Just check the manufacturer’s spec for bend radius before purchasing the products. If no recommendations are available from the cable manufacturer, the cable should not be pulled into a bend radius smaller than twenty times the cable diameter. For example, a cable with an outer diameter of 5 mm, should not be bent smaller than 100mm radius during installation.

Maintaining proper bend radius is key in preventing service calls due to damage and signal loss in your optical fiber. Bend loss usually occurs when the fiber cable bends is tighter than the cable’s maximum bend tolerance, which might damage the fiber by causing micro cracks.

There are a couple of factors that may mitigate the problems of bend radius and the angles within them. If a fiber cable is being pulled or pushed through an empty duct or mini-duct, obviously there is less resistance to the cable and you can pull/push greater distances. If the coating of the outside of the cable and the inside of the duct are designed to reduce friction, you will be able to achieve greater distances as well.

With well-designed bend insensitive fiber patch cables (seen in the above image), you can usually push a fiber cable as far as 90 degree angles in the run with minimized signal loss compared with the traditional fiber patch cables.

Tensile Strength

Just as the bend radius, fiber optic cables also have a maximum tensile strength. If the cable is being pulled through, it is better not to exceed the maximum tensile load. However, if the cable is being installed within a microduct or conduit, pushing the cable will apply no tensile force.

Over-stressing the fibers will not be noticeable until after installation since the cable outer sheath will elongate, whereas glass optical fiber will not. Ideally, a breakaway swivel should be used, however, where this is not possible, the installation crews should use a tension gauge attached to the pull-cord. As a rough approximation, 100 Newtons is equivalent to a 22lbf (pounds-force) load applied directly to the cable.

Usable Duct Space

The full space in the duct is not usable for cables because of horizontal and vertical bends and joints. Usable duct space should be at least 60%. 900µm and 250µm fibers are basically two kinds of fiber patch cables. 900µm fibers can easily be damaged with respect to the storage and wire management. 900 µm kinks easily, but is very flexible and installs easily. Sometimes, you have to balance ease of installation with toughness. The difference between 250um Loose-tube and 900um Tight Buffered Fiber have illustrated in the above article.

During the cable installation, you must get the fiber through walls—possibly in basements, attics, or crawl spaces, and then through floors, walls and, eventually, through a room to the CPE location. For rugged spaces where your fiber may suffer damage, such as basements or in conduits sharing space with electrical or other wiring, you may need a 3mm rugged sheathed cable that is flexible and crush resistant. The image below shows fiber optic cables being kinked. The flat cat5e cables (left) and common Ethernet cable (right) have different effect after bending.

Therefore, a good rule of thumb to use in planning your fiber drop is below: Bends (angles) = Friction—maximum distance of the pushable fiber

In addition to the above bend radius, here are some other areas to focus on to achieve maximum distance without damaging the cable: signal power and performance requirements for each device or revenue generating unit, locations of required splices, list of cable lengths required. When using duct or cable in conduit, keep in mind that freezing water in the conduit can crush the cable—and it may be wise to use microduct.

Summary

One of the challenges of installing fiber is to choose a cable with a very small bend radius, and it is tough enough to handle many different installation conditions. Once you have selected the appropriate fiber, plan your route to minimize bends and friction. By planning ahead and thinking carefully, you can save money by reducing the costs of those services. FS.COM, as a professional telecom vendor, offers a full range of cable management components, like the patch panels, cable manager & wire duct, fiber enclosures and so on. Some special cables including the bend insensitive fiber patch cables, flat fiber optic cables are also offered. If you have any interest, please send your request to us.

Difference Between 50 Ohm and 75 Ohm Coaxial Cable

People know much about the coaxial cables, but they know little about the different impedance of coaxial cables, namely 50 Ohm and 75 Ohm coaxial cables. Even many optical manufacturers fail to adequately explain the difference between the two types of coax and why they need one type over the other. Therefore, today’s article will define some of the most critical concepts regarding coaxial cable technology, and shed light on the difference between these two coaxial types.

What’s Ohm?

An Ohm is the unit of resistance used to measure the flow of electrical current through a circuit. In the most basic applications where we are dealing with DC or Direct Current electricity, we are measuring the resistance in Ohms. It is known that the smaller the Ohm, the better the performance. So a 50 Ohm cable provides much better results than a 75 Ohm cable. However, you can find the 75 Ohm cables are everywhere inside your home from the back of the TV to cable & satellite TV boxes and internet routers. Why does the 75 Ohm coaxial cables have the poor impedance but still win large popularity in the home network? In fact, there really is no good or bad impedance, just the right impedance for your application. For the detailed information about these two types of coaxial cables, please read on.

Shedding Light on Coaxial Cable

Coaxial cable, as one type of the bulk fiber optic cable, is comprised of three main components—center conductor, dielectric and shield. Center conductor as the name implies, is in the middle of the coaxial cable that can be made of either solid or stranded wire. Surrounding the center conductor is something called the dielectric. The dielectric acts as a buffer of sorts to keep the center conductor isolated and straight. Finally, on the outside of the dielectric is the coaxial cable’s shield, which is usually a combination of Copper and Aluminum foil and/or wire braid. The shield is then coated by something like PVC to insulate it from the environment. As noted before, coaxial cable can be divided into two types according to different impedance: 50 Ohm and 75 Ohm.

50 Ohm Coaxial Cables: The Forgotten Impedance

First, let’s look at 50 Ohm Coaxial Cables. Experimentation in the early 20th century determined that the best power handling capability could be achieved by using 30 Ohm Coaxial Cable, whereas the lowest signal attenuation (LOSS) could be achieved by using 77 Ohm Coaxial Cable. However, there are few dielectric materials suitable for use in a coaxial cable to support 30 Ohm impedance. Thus, 50 Ohm Coaxial Cable was selected as the ideal compromise; offering high power handling AND low attenuation characteristics.

With 50 Ohm coaxial cables being the best compromise solution, practically any application that demands high power handling capacity, i.e. 100 watts or more, will use 50 Ohm Coaxial Cable. A good rule of thumb is that any device that functions as a transmitter or transceiver tends to use 50 Ohm Coaxial Cable. This includes devices such as CB/Ham Radios, Broadcast Radio/TV Transmitters, Wi-Fi and Cellular Phone Repeaters and 2-Way Radios seen in the below image. And since 50 Ohm cables aren't as ubiquitous as 75 Ohm cables in the home network, running cable is potentially more difficult if your building is not pre-wired for it. Seriously, the cable is noticeable bigger than a 75 Ohm.

75 Ohm Coaxial Cable is the Way to Go

However, not every case warrants high power handling, so 50 Ohm Coaxial Cable is not appropriate for every application. When the objective is to ensure that the signal gets through the cable in the most efficient way possible, losing very little signal strength in the process, 75 Ohm Coaxial Cable is the way to go. This includes devices such as Satellite and Cable TV Receiver Boxes, High Definition Televisions, AM/FM Radio Receivers and Police Scanners as you can see in the following image.

With the features of low attenuation and capacitance effectively, 75 Ohm coaxial cable becomes the cable of choice for practically all types of digital audio, digital video and data signals. This is also the reason why every cable TV company uses 75 Ohm coax for distributing its digital video channels as well as its broadband internet data signals. Additionally, direct broadcast satellite dishes and over-the-air HDTV antennas require 75 Ohm Coaxial Cable to ensure that all of the digital channels transfer down the cable with the lowest loss and distortion possible.

75 Ohm cables are the standard coax cable and they're commonly used and are often pre-wired in many homes and businesses. In all, 75 Ohm is primary used for video and audio, hence why it's rapid adoption.

Conclusion

To sum up, the 75 Ohm cable is the primarily utilized for the transmission of a video signal. In the case of 50 Ohm cable, it is a data signal that is for the most part being transmitted. To put it simply, 75 Ohm is for pictures and 50 Ohm is for information. FS.COM is committed to provide the best services and first-class fiber optics to all of our customers. Besides the copper cable (coaxial cables and twisted cables), fiber optic cables are also provided with large selection and high quality. Feel welcome to contact us.