What Will Affect the Longevity of Your Fiber Network?

by Fiber-MART.COM

When deploying a fiber network, people nowadays not only appreciate the high-speed broadband services, but the maintenance of how long it will last. After all, optical fiber is a particular type of hair-thin glass with a typical tensile strength that is less than half that of copper. Even though the fiber looks fragile and brittle, but if correctly processed, tested and used, it has proven to be immensely durable. With this in mind, there are essentially factors that will affect the longevity of your fiber network.

 

Installation Strains

 

Stress, on the other hand, is a major enemy of fiber longevity, so the protection task is passed to the cable installer, who will ensure that the use of suitable strength elements limits the stress applied to the cable to much less than the 1 per cent proof test level. The installer then needs to ensure that the deployment process does not overstrain the cable. Figure 2 below illustrates a typical crew deployment for a trunk installation. The whole process should be paid more attention to the stress.

 

Of the three techniques commonly used—pulling, pushing and blowing, only pulling creates undesirable stretching (tensile stress). Unlike metal, glass does not suffer fatigue by being compressed, and so the mild compression caused during pushing causes no harm to the fiber.

 

Surface Flaws

 

Optical fiber typically consists of a silica-based core and cladding surrounded by one or two layers of polymeric material (see in Figure 3). Pristine silica glass that is free of defects is immensely resistant to degradation. However, all commercially produced optical fibers have surface flaws (small micro-cracks) that reduce the material’s longevity under certain conditions. The distribution of flaws on the surface of the silica-based portion of the fiber largely controls the mechanical strength of the fiber. FS.COM fiber optic cables are well tested to ensure less surface flaws, like LC to ST fiber cable.

 

To conquer this, reputable fiber suppliers carry out proof testing, which stretches the fiber to a pre-set level (normally 1 per cent) for a specified duration to deliberately break the larger flaws. And the user is then left with a fiber containing fewer, smaller flaws that need to be protected from unnecessary degradation. This means primarily stopping the creation of new flaws by coating the fiber with a protective and durable material for its primary coating.

 

Environmental Factors

 

Once deployed, the local environment has a big impact on fiber life. Elevated temperatures can accelerate crack growth, but it is the presence of water that has been historically of most concern. The growth of cracks under stress is facilitated by water leading to "stress corrosion".

 

You can check what the tendency of a fiber to suffer stress corrosion is by reviewing its "stress corrosion susceptibility parameter", much more conveniently referred to as "n". A high n value (around 20) suggests a durable fiber and coating.

 

Calculating How Long Your Network Will Last

 

Bearing in mind the three factors above, how can you calculate the lifetime of your fiber network? In general, the chances of a fiber being damaged by manual intervention, such as digging, over the same time frame is about 1 in 1,000. Quality fiber, installed by benign techniques and by careful installers in acceptable conditions should, therefore, be extremely reliable - provided it is not disturbed.

 

It is also worth pointing out that cable lengths themselves have rarely failed intrinsically, but there have been failures at joints where the cable and joint type are not well matched, allowing the fibers to move - for example, due to temperature changes. This leads to over stress of the fiber and eventual fracture.

 

Conclusion

 

To tell the truth, the biggest enemies to the carefully engineered reliability of fiber jumper can be either humans or animals, rather than the fused silica itself. The provided fibers are stored and coiled correctly, it is quite possible that they turn out to be stronger than we at first thought and perhaps the original flaws begin to heal with time and exposure to water under low stress levels. FS.COM offers high quality fiber cable assemblies such as Patch Cords, Pigtails, MCPs, Breakout Cables etc. All of our products are well tested before shipment. If you are interested, you can have a look at it.

How to Use Field Assembly Connector?

by Fiber-MART.COM

The expansion of FTTH application has brought prosperity to the manufacturing of field assembly connectors for fast field termination. This type of connector gains its popularity due to the applicability to cable wiring and compact bodies which are easily stored in optical fiber housings. With excellent features of stability and low loss, field assembly connector has now become a reliable and durable solution for fiber optic systems. However, do you really know the field assembly process of the connector? This article provides an easy guide to show you the way of using field assembly connector.

Introduction to Field Assembly Connector

Before getting to know the instruction process, let’s have a look at the basic knowledge about field assembly connector. Field assembly connector or fast connector is an innovative field installable optical fiber connector designed for simple and fast field termination of single fibers. Without using additional assembling tools, field assembly connector can be quickly and easily connected to the drop cable and indoor cable, which saves a lot of required termination time. It is specially designed with the patented mechanical splice body that includes a factory-mounted fiber stub and a pre-polished ceramic ferrule. Field assembly connector is usually available for 250 µm, 900 µm, 2.0 mm and 3.0 mm diameter single-mode and multimode fiber types. The whole installation process only takes about 2 minutes which greatly improves the working efficiency.

Internal Structure of Field Assembly Connector

From the following figure, we can see the specific internal structure of field assembly connector. The ferrule end face of the connector is pre-polished in a factory for later connection with the fiber. A mechanical splice is also formed at the end of the ferrule for mechanical fixation of optical fiber. The mechanical splice consists two plates, one with a V groove, another with flat surface above the V groove, and a clamp for the insertion of the two plates. When inserting the fiber, a wedge clip will keep the V groove open for easier installation. After the fiber insertion, the wedge clip can be extracted from the V groove.

Features and Applications

Key Features

Field-installable, cost-effective, user-friendly

No requirement for epoxy and polishing

Quick and easy fiber termination in the field

No need for fusion splicer, power source and tool for pressure

Visual indication of proper termination

Applications

Fiber optic telecommunication

Fiber distribution frame

FTTH outlets

Optical cable interconnection

Cable television

Field Assembly Instruction Guide

Although it is an simple way to use field assembly connector, the right operation process is also important. Here will introduce some basic steps for connector installation.

Step 1, prepare the field assembly connector parts and related tools required during the process. There is no need for special tools, but fiber cleaver and jacket stripper are still necessary.

Step 2, insert the connector boot into the fiber cable.

Step 3, cut and reserve 10mm bare fiber by fiber cleaver and then make sure the total fiber length of 30 mm.

Step 4, insert the fiber from bottom until the stopper and make fiber present micro bend.

Step 5, press the press cover to tight the bare fiber.

Step 6, lock the boot with yarn.

Step 7, cut the yarn.

Step 8, screw the boot and put on housing to complete assembly.

Precautions

Here are some precautions for you to notice during the process:

Point 1, the product is sensitive to dirt and dust. Keeping it away from any possible contamination is necessary.

Point 2, the performance will be influenced by the fiber cutting surface condition. Use a cutter with a sharp blade for the best results.

Point 3, insert the fiber into the connector slowly. If the fiber is roughly inserted, it might be damaged or broken, leading to failure of connector installation. Broken fiber could scatter in all directions.

Point 4, do not remove the dust cap until the connector has been completely assembled in order not to cause a high insertion loss.

Point 5, a proper amount of index matching gel is applied in the connector. Do not insert fiber more than once into connector.

Conclusion

Fiber assembly connector enables quick termination to improve reliable and high connector performance in FTTH wiring and LAN cabling systems. All the above solutions provided by fiber-mart.COM are available to meet your requirements. Please visit the website for more information.

Understanding OTDR Dead Zone Specifications

by Fiber-MART.COM

OTDR (Optical Time Domain Reflectometer), as one of the important fiber optic testers, is most commonly used by technicians or installers to certify the performance of new fiber optic links and detect the issues of existing fiber links. There are some specifications of an OTDR which may affect its performance. To understand these specifications can help users get maximum performance from their OTDRs. Today, one of the key specifications—Dead Zone will be introduced here.

 

Definition of Dead Zones

The OTDR dead zone refers to the distance (or time) where the OTDR cannot detect or precisely localize any event or artifact on the fiber link. It is always prominent at the very beginning of a trace or at any other high reflectance event.

 

Why Is There a Dead Zone?

In simple terms, OTDR dead zone is caused by a Fresnel reflection (mainly caused by air gap at OTDR connection) and the subsequent recovery time of the OTDR detector. When a strong reflection occurs, the power received by the photodiode can be more than 4,000 times higher than the backscattered power, which causes detector inside of OTDR to become saturated with reflected light. Thus, it needs time to recover from its saturated condition. During the recovering time, it can not detect the backscattered signal accurately which results in corresponding dead zone on OTDR trace. This is like when your eyes need to recover from looking at the bright sun or the flash of a camera. In general, the higher the reflectance, the longer the dead zone is. Additionally, dead zone is also influenced by the pulse width. A longer pulse width can increase the dynamic range which results in a longer dead zone.

 

Types of Dead Zones

In general, there are two types of dead zones on an OTDR trace—event dead zone (EDZ) and attenuation dead zone (ADZ).

 

Event Dead Zone

The event dead zone is the minimum distance between the beginning of one reflective event and the point where a consecutive reflective event can be detected. According to the Telcordia definition, event dead zone is the location where the falling edge of the first reflection is 1.5 dB down from the top of the first reflection.

 

Attenuation Dead Zone

The attenuation dead zone is the minimum distance after which a consecutive non-reflective event can be detected and measured. According to the Telcordia definition, it is the location where the signal is within 0.5 dB above or below the backscatter line that follows the first pulse. Thus, the attenuation dead zone specification is always larger than the event dead zone specification.

 

Note: In general, to avoid problems caused by the dead zone, a launch cable of sufficient length is always used when testing cables which allows the OTDR trace to settle down after the test pulse is sent into the fiber so that users can analyze the beginning of the cable they are testing.

 

There is always at least one dead zone in every fiber—where it is connected to the OTDR. The existence of dead zones is an important drawback for OTDR, specially in short-haul applications with a large number of fiber optic components. Thus, it is important to minimize the effects of dead zones wherever possible.

 

As mentioned above, dead zones can be reduced by using a lower pulse width, but it will decrease the dynamic range. Thus, it is important to select the right pulse width for the link under test when characterizing a network or a fiber. In general, short pulse width, short dead zone and low power are used for premises fiber testing and troubleshooting to test short links where events are closely spaced, while a long pulse width, long dead zone and high power are used for long-haul fiber testing and communication to reach further distances for longer networks or high-loss networks.

 

The shortest-possible event dead zone allows the OTDR to detect closely spaced events in the link. For instance, testing fibers in premises networks (particularly in data centers) requires an OTDR with short event dead zones since the patch cords of the fiber link are often very short. If the dead zones are too long, some connectors may be missed and will not be identified by the technicians, which makes it harder to locate a potential problem.

 

Short attenuation dead zones enable the OTDR not only to detect a consecutive event but also to return the loss of closely spaced events. For instance, the loss of a short patch cord within a network can now be known, which helps technicians to have a clear picture of what is actually inside the link.

 

Conclusion

OTDR is one of the most versatile and widely used fiber optic test equipment which offers users a quick, accurate way to measure insertion loss and shows the overview of the whole system you test. Dead zone, with two general types, is an important specification of OTDR. It is necessary for users to understand dead zone and select the right configuration in order to get maximum OTDR performance during test. In addition, OTDRs of different brands are designed with different minimum dead zone parameters since manufacturers use different testing conditions to measure the dead zones. Users should choose the suitable one according to the requirements and pay particular attention to the pulse width and the reflection value. Fiberstore offers various OTDRs of the major brands, such as JDSU, EXFO, YOKOGAWA etc., as well as other portable and handheld OTDRs with wide options. For more information, please contact us via sales@fiber-mart.com.

China factory of the ZTE XFP-10GE-S40K compatible transceivers

A fiber optic transceiver is a device used to transmit and receive optical signals in a optical network. Optical transceiver facilitates bi-directional data transmissions between electronic devices (e.g., computer, input/output system, peripheral device, or switch) and optical data links in fiber optic systems. Fiber optic transceivers can interface with single mode and multimode fiber cable. Single mode is an optical fiber that will allow only one mode to propagate. The fiber has a very small core diameter of approximately 8 µm. It permits signal transmission at extremely high bandwidth and allows very long transmission distances. Multimode describes a fiber optic cable, which supports the propagation of multiple modes. Multimode fiber may have a typical core diameter of 50 to 100 µm with a refractive index that is graded or stepped. It allows the use of inexpensive LED light sources and connector alignment and coupling is less critical than single mode fiber. Distances of transmission and transmission bandwidth are less than with single mode fiber due to dispersion.

All our transceivers are 100% compatible with major brands like Cisco, HP, Nortel, Force10, D-link, 3Com, and backed by a lifetime warranty. Buy with confidence.We offer a best price guarantee. If you find a price lower than ours plus free shipping on the Qualified Internet Retailer sites, you may qualify for an even better price.

Atrone (Philippines) Inc is real China transciever modules factory,we are professional supplier of ZTE XFP-10GE-S40K transceivers, you can save much cost and get best tech support of the ZTE XFP-10GE-S40K modules, we are not affiliated with any of the brand names mentioned on this website, and does not sell their products or components. These Brand names are registered trademarks of their respective owners in the United States and other countries and are used here only to describe PRODUCT COMPATIBILITY.

The market forecast of the active optical cable (AOC)

The active optical cable (AOC) market has experienced many challenges, from the Integrate acquisitions, to the entrance of the Asia suppliers which provide low-cost price, the Japanese earthquake and tsunami and the influx of the Taiwan manufacturers and finally to the intellectual property battle between established suppliers.

By 2012, the market restored the stability and is expected to achieve sustained strong growth in 2013.

 

At present, InfiniBand market occupies the largest market share and has been transferred to 14G FDR QSFP+. While the traditional data center still remains in the 10G QSFP+ format. The active optical cable (AOC) also has potential development opportunities in other protocol, such as SAS, Fibre Channel and PCI Express and other protocol whose transmission data rate is over 10G.

 

As a professional fiber optic products manufacturer and supplier, we offer 40G QSFP+ modules, 40G QSFP+ cables and other products, such as 10G SFP+ Modules, XFP Transceivers and so on. For more information, please contact our customer services.

10GSFP-AOC-5

SFP+ AOC (Active Optical Cable) assemblies use active circuits to support longer distances than standard passive or Active SFP+ Copper Cables. They are designed for high speed, short range data link via optical fiber wire. SFP+ AOC cables provide high performance Enhanced Small Form Factor Pluggable (SFP+) interface and is a cost effective solution for Data Center/storage and all short range data application.
All our SFP+ cables are 100% compatible with major brands like Cisco, Juniper, Enterasys, Extreme, H3C and so on. If you would like to order high quality compatible SFP+ cables and get worldwide delivery, we believe Fiber-mart.COM is your best choice.

Specifications

• 10Gb/s serial optical interface
• Length: 5 meters
• Wire AWG: Fiber
• Connector 1 : SFP+ AOC
• Connector 2 : SFP+ AOC
• Low cost alternative to fiber optic assemblies
• Low power consumption
• Bend insensitive fiber
• Single 3.3V power supply
• RoHS-6 compliant
• Mechanical specifications compliant with SFF-8432
• Electrical specifications compliant with SFF-8431
• Operating Temperature: 0-70℃
• Support digital diagnostics monitoring for module temperature, Vcc, Rx input power, Tx_Disable and Rx_LOS
• Hot pluggable
• 12C communication bus

 

What's the best way to terminate fiber optic cable?

What's the best way to terminate fiber optic cable? That depends on the application, cost considerations and your own personal preferences. The following connector comparisons can make the decision easier.

Epoxy & Polish

Epoxy & polish style connectors were the original fiber optic connectors. They still represent the largest segment of connectors, in both quantity used and variety available. Practically every style of connector is available including ST, SC, FC, LC, D4, SMA, MU, and MTRJ. Advantages include:

• Very robust. This connector style is based on tried and true technology, and can withstand the greatest environmental and mechanical stress when compared to the other connector technologies.

• This style of connector accepts the widest assortment of cable jacket diameters. Most connectors of this group have versions to fit onto 900um buffered fiber, and up to 3.0mm jacketed fiber.

• Versions are. available that hold from 1 to 24 fibers in a single connector.

Installation Time: There is an initial setup time for the field technician who must prepare a workstation with polishing equipment and an epoxy-curing oven. The termination time for one connector is about 25 minutes due to the time needed to heat cure the epoxy. Average time per connector in a large batch can be as low as 5 or 6 minutes. Faster curing epoxies such as anaerobic epoxy can reduce the installation time, but fast cure epoxies are not suitable for all connectors.

Skill Level: These connectors, while not difficult to install, do require the most supervised skills training, especially for polishing. They are best suited for the high-volume installer or assembly house with a trained and stable work force.

Costs: Least expensive connectors to purchase, in many cases being 30 to 50 percent cheaper than other termination style connectors. However, factor in the cost of epoxy curing and ferrule polishing equipment, and their associated consumables.

Pre-Loaded Epoxy or No-Epoxy & Polish

There are two main categories of no-epoxy & polish connectors. The first are connectors that are pre-loaded with a measured amount of epoxy. These connectors reduce the skill level needed to install a connector but they don't significantly reduce the time or equipment need-ed. The second category of connectors uses no epoxy at all. Usually they use an internal crimp mechanism to stabilize the fiber. These connectors reduce both the skill level needed and installation time. ST, SC, and FC connector styles are available. Advantages include:

• Epoxy injection is not required.
• No scraped connectors due to epoxy over-fill.
• Reduced equipment requirements for some versions.

Installation Time: Both versions have short setup time, with pre-loaded epoxy connectors having a slightly longer setup. Due to curing time, the pre-loaded epoxy connectors require the same amount of installation time as standard connectors, 25 minutes for 1 connector, 5-6 minutes average for a batch. Connectors that use the internal crimp method install in 2 minutes or less.

Skill Level: Skill requirements are reduced because the crimp mechanism is easier to master than using epoxy. They provide maximum flexibility with one technology and a balance between skill and cost.

Costs: Moderately more expensive to purchase than a standard connector. Equipment cost is equal to or less than that of standard con¬nectors. Consumable cost is reduced to polish film and cleaning sup-plies. Cost benefits derive from reduced training requirements and fast installation time.

No-Epoxy & No-Polish

Easiest and fastest connectors to install; well suited for contractors who cannot cost-justify the training and supervision required for standard connectors. Good solution for fast field restorations. ST, SC, FC, LC, and MTRJ connector styles are available. Advantages include:
• No setup time required.
• Lowest installation time per connector.
• Limited training required.
• Little or no consumables costs.

Installation Time: Almost zero. Its less than 1 minute regardless of number of connectors.

Skill level: Requires minimal training, making this type of connector ideal for installation companies with a high turnover rate of installers and/or that do limited amounts of optical-fiber terminations.

Costs: Generally the most expensive style connector to purchase, since some of the labor (polishing) is done in the factory. Also, one or two fairly expensive installation tools may be required. However, it may still be less expensive on a cost-per-installed-connector basis due to lower labor cost.

The Ports On CWDM and DWDM MUX/DEMUX

It is quite common to use CWDM or DWDM to increase the existing fiber optic network without adding any fibers. Using WDM MUX/DEMUX is necessary to build a CWDM or DWDM network. Now there are different ports installed on the CWDM and DWDM MUX/DEMUXs to add more beneficial to the fiber optic network. This post will offer details about the ports on CWDM and DWDM MUX/DEMUX.

 

DWDM MUX/DEMUX Port

The basic function of the CWDM and DWDM MUX/DEMUX is combining data rate of different wavelengths over the same fiber cable to increase the network capacity. Thus, channel ports supporting different wavelengths and Line port used to connect the WDM MUX/DEMUX are the must-have ports for these devices.

CWDM uses 18 wavelengths ranging from 1270nm to 1610nm with a channel space of 20nm. Channel port count on CWDM MUX/DEMUX is usually ranging from 2 to 18. The following picture shows a full-channel CWDM MUX/DEMUX with all the 18 CWDM wavelengths: 1270nm, 1290nm, 1310nm, 1330nm, 1350nm, 1370nm, 1390nm, 1410nm, 1430nm, 1450nm, 1470nm, 1490nm, 1510nm, 1530nm, 1550nm, 1570nm, 1590nm, 1610nm.

18CH CWDM MUX/DEMUX

 

DWDM uses the wavelength ranging from 1470nm to 1625nm usually with channel space of 0.8nm (100GHz) or 0.4nm (50GHz). DWDM MUX/DEMUX can support much more wavelengths that of CWDM MUX/DEMUX. The channel port of a DWDM MUX/DEMUX is usually ranging from 4 to 96.

Line Port

 

There are two types of line port available for CWDM and DWDM MUX/DEMUX. One is dual fiber line port, and the other is single fiber line port. The selection of the line port depends on applications. The WDM MUX/DEMUX with a single fiber line port is very different from the WDM MUX/DEMUX with a dual fiber line port on the using of wavelengths.

 

Dual-fiber MUX/DEMUX uses the same wavelength for dual-way transmission, which means the TX port and RX port of every duplex channel port supporting the same wavelength. The WDM MUX/DEMUXs with dual fiber line ports installed on the two ends of the network could be the same.

 

signle-fiber DWDM MUX/DEMUX

 

For single-fiber WDM MUX/DEMUX, all the wavelengths just flow in one direction. And the TX port and RX port of every duplex channel port supporting two different wavelengths. The above picture shows the front panel of an 8-channel DWDM MUX/DEMUX with single-fiber line port. As it is clearly marked the TX port and RX port use different wavelengths. If you choose a single-fiber WDM MUX/DEMUX on one side of the network, there should be a single-fiber WDM MUX/DEMUX which supports the same wavelengths but has the reverse order on the TX port and RX port of every duplex channel port. Please note, the line port of some  single-fiber CWDM MUX/DEMUXs is made into a duplex port, but one one port is function. Here takes the example of fiber-mart.COM FMU CWDM MUX/DEMUX as an example, as shown in the following picture, the single-fiber CWDM MUX/DEMUX has a duplex port, but one of the port marked as “N/A” is not in use.

 

single-fiber CWDM line-port

 

The Functioning Ports on CWDM and DWDM MUX/DEMUX

Except the above mentioned must-have channel ports and line port, WDM MUX/DEMUX can also be added with other ports which bring more profits to the existing WDM network. The following will introduce these special ports that are often added on CWDM and DWDM MUX/DEMUX.

Expansion Port

 

Expansion port added on WDM MUX/DEMUX is really useful. If you installed a CWDM network which just using several of the CWDM wavelengths, you can use this expansion port to increase the network capacity by connecting the expansion port with the line port of another CWDM MUX/DEMUX supporting different wavelengths. Then the network of this CWDM network can be increased easily. Both CWDM MUX/DEMUX and DWDM MUX/DEMUX support this expansion port. Kindly click the following picture for details of how to use expansion port.

WDM Expansion Solution

 

1310nm Port and 1550nm Port

The 1310nm and 1550nm are actually WDM wavelengths. How could these two wavelengths become special? It can be recognized that many fiber optic signals for are transmitted over 1310nm and 1550nm. Many fiber optic transceivers support long distances use these two wavelengths. However, the standard channel port on WDM MUX/DEMUX can only be connected to color coded fiber optic transceiver like CWDM SFP/SFP+ and DWDM SFP/SFP+. With these special designed 1310nm port and 1550nm port, the signal running through ordinary fiber optic transceivers can be combined together with other CWDM wavelengths.

 

Please note that DWDM MUX/DEMUX can only add special 1310nm port. For CWDM MUX/DEMUX, not all the wavelengths can be added, if you add special 1310nm or 1550nm port on the device. There is a simple rule for how to add the special ports and other standard channel ports on CWDM MUX/DEMUX. If you want to add 1310nm or 1550nm ports on your CWDM MUX/DEMUX, wavelengths which are 0-40nm higher or lower than 1310nm or 1550nm cannot be added to the MUX. The following table shows the specific details.

 

Monitor Port

Many technicians will add a monitor port on CWDM or DWDM MUX/DEMUX for better network monitoring and management. If you choose a single-fiber WDM MUX/DEMUX, the monitor port should be a simplex fiber optic port. For dual-fiber WDM MUX/DEMUX, you can add a duplex monitor port for the whole network monitoring, or just add a simplex port for MUX or DEMUX monitoring.

MUX/DEMUX monitor port

 

fiber-mart.COM WDM CWDM and DWDM Solution

The above mentioned ports are the most commonly used in WDM MUX/DEMUX. All these ports can be customized in fiber-mart.COM where affordable complete solutions for CWDM, DWDM and DWDM over CWDM network are available. Kindly contact sales@fiber-mart.com for more details if you are interested.

UNDERSEA CABLE, THE INTERNETS BACKBONE

How it works

 

Rarely do we sit back a truly appreciate the tremendous effort that has been made in order to achieve what seems so simple on the surface. As we flick though the latest fashion posts on our tablets, read email reports on our laptops at the local coffee shop, we really don’t give much though to how that information got there and the daily challenges faced by many to bring us this convenience. Let’s dive in shall we?

 

Undersea or submarine cable is essentially the backbone of the internet and what allows countries and continents to share information between one another. While satellite communications are highly effective it is simply more reliable and cost effective to make use of fiber optic undersea cables. This is not to say that undersea cable is cheap by any stretch of the imagination.

 

Submarine cable is placed on the sea bed between land based stations in order to convey signals across the ocean. With the first communication cables being laid as early as the 1850’s for use in telegraphy. Later on these cables would advance in order to make use of  modern fiber optic and carry digital data including telephony and the internet.

 

Typical modern undersea cables are far larger than fiber cable used in everyday land use. They are usually around 25 mm (0.98 in) in diameter and have a tremendous weight of around 1.4 kg per meter (0.4 lb/ft), although much larger and heavier ones are in use around shallower areas and nearer to shore.

 

How is it Laid?

 

The cables are laid gently on the ocean floor by specifically designed ships and in most cases remain submerged due to their weight. The cables are designed with an average life-span of 25 years, this however does not mean they are immune to breakages prior to this. There are a number of reasons a cable can fail including anything from simple degradation to shifts in the ocean floor. This of course means that repairs will be required and this in turn requires specialized equipment and specially trained personnel to carry out the work.

 

Repairing Undersea Cable

Should there be an issue with a submarine cable it must be  raised to the water surface and worked on from there.  It is a fairly complex operation in which a cable repair ship will be dispatched to the location and the deploy a marker buoy near the break. Once there the cable will be grappled off the ocean floor and raised in order to begin repairs, various types of grapples are used depending primarily on the conditions of the ocean floor. Cable repair can be both a lengthy and dangerous for all involved with work crews having to often postpone repairs due to inclement weather conditions, regardless of the state of repair they where currently in. Once splicing of the cable has taken place the repaired cable will be returned to the seabed , the repaired cable will be longer than the original, so the excess is deliberately laid in a ‘U’ shape on the ocean floor. This is done in the hopes of preventing future damage to the cable.

 

Final Thoughts

 

Connecting the world is far from simple and very, very expensive, so next time your cruising the internet super highway give some thought to the technologies that enable you to send that email, share that photo of your lunch or pay for that designer dress in Milan.