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FIOS: What is it? How it Works?
104 days
With Fios the future of data delivery is now, offering the big three, Phone, Cable, and Internet. Here you’ll find out what FIOS is all about, and how it works?
Verizon FIOS is one of the newest offerings into the Phone/Internet/TV world – a technology and service which threatens to revolutionize the delivery of data to homes or offices. FIOS offers an alternative to existing analog technology, and provides a digital only connection to an increasingly digital world. With 12.7 million homes able to access FIOS service at the beginning of the year and 2.5 million subscribers to FIOS Internet with 1.9 million FIOS TV customers, Verizon FIOS has become one of the fastest growing communications carriers in the nation.
The Last Mile In Service
FIOS stands for Fiber Optic Service; it’s a system of data delivery that uses fiber optics, strands of pure glass, in order to deliver digital-only service straight to users without the limitations often associated with the copper wire used in older delivery systems such as cable television or landline telephones. Through the use of fiber optics, FIOS is capable of offering higher Internet speeds and a greater range of television channels than those available through its closest competitors.
Verizon FIOS utilizes a system known as fiber to the premises (FTTP) to provide its FIOS services. The technology is capable of providing a host of services consisting of Digital Television, Internet, and Telephone. While the technology has been around for years, FIOS is the first offering by a major U.S. carrier for consumer and business uses. In offering fiber to the premises FIOS has taken the final step in digital delivery to the consumer, while most other providers of the same services use fiber only in the network backbone, relying on existing cable or coax installations to provide the last mile of service from hub to consumer.
How It All Works
The data over the FIOS service is delivered through the use of passive optical network technology. A passive optical network is a method of using a single optical fiber to service multiple premises. Single-mode optical fiber is extended from the carrier’s network hub into the customer’s neighborhood where it is split using an optical splitter into up to 32 separate fibers, each serving a single premise. At the premise an optical network terminal (ONT) is installed and sends the data received along the network into the household wiring for telephone, video, and Internet access.
Communication over a fiber-optic cable is done through light emission along the glass fibers. The light creates an electromagnetic carrier wave which is then modulated to carry data along a signal. A transmitter creates an electrical signal into an optical signal which is relayed along the line to a receiver which converts the optical signal back into an electrical signal readable by the equipment at the other end. During the signal progress, the signal is often amplified to prevent degradation, or relayed through a series of repeaters.
The data is carried over three wavelength bands. One devoted to television channels, and two devoted to data, the first for inbound traffic, second for outbound traffic. FIOS television is broadcast from the master television facility, to a local video hub office, then on to the subscriber’s premise where the optical network terminal converts the signals into a form compatible with cable television systems. Telephone over FIOS is usually an analog offering, often referred as plain old telephone service (POTS), and is the basic telephone service offered in most parts of the world. The ONT typically houses 2 to 4 telephone jacks but unlike copper wire based telephone service, fiber optics carry no power, so power outages will knock out phone service as well as everything else. Internet connectivity is provided by the ONT via an RJ45 connector, with speeds offered of up to 50Mbps down/ 20Mbps up.
What You Get With Installation
Most FIOS installations use the Tellabs 1600 series brand ONT. The Tellabs ONT allows for 2 to 4 voice telephone ports with native POTS and Voice-over-IP (VoIP), includes a gigabit Ethernet interface for data with the capability of Power-over-Ethernet (PoE), and a coaxial connector for cable television broadcasts. To deal with power outage concerns it comes with a rechargeable battery back-up option that allows for 4 to 8 hours of continuing power to the ONT. Another common ONT in usage is the Motorola ONT1000M which provides the same quality of service, but is only capable of 100MBPS Ethernet and used primarily in single family households. The router installed in the home is usually an Actiontec MI424-WR broadband wireless-G router, which is used for both TV and Internet service. The MI44-WR offers a WAN coaxial connection along with the four 10/100 megabit Ethernet ports and a single 10/100 megabit Ethernet uplink port.
Installation of the service is not a brief process. It’s been known to take upwards of 5 hours to complete as a great deal of work has to take place in order to get the fiber to the premise. The installation requires both outside and inside wiring, and the mounting of the ONT, usually near the existing telephone box. For apartments, Verizon usually mounts larger ONTs capable of servicing multiple households. These ONTS are placed floor by floor in a complex, and can speed up individual installs significantly. Installation does not negate the old technology already present however, and rollback from FIOS is possible if necessary.
Verizon FIOS service is the latest step in the digital communications revolution, a step closer to the day when all information is transmitted along digital means. Speeds and bandwidth allowable under the system are much higher than their analog equivalents, and the equipment used allows for growth that traditional analog systems simply can’t match. And by using fiber to the premise, Verizon hopes to satisfy the increasing needs of a data hungry world.
What Fiber Optic Supplies Do You Need To Clean A Fiber Optic Connector?
314 days
First, let’s understand why a fiber optic connector needs cleaning.
You may never need to clean the RJ45 connector for your computer’s Ethernet network connection, then why do you need to clean a fiber optic connector if it serves the same purpose as a networking connection?
While, the answer lies in how optics work differently than electronics. In electronics, as long as you have a contact between two connectors, they work perfectly; or at least most of the time.
But for optics, light beams travel in straight lines, they bounce off whenever they hit anything and thus loss their energy.
So in order for a light beam to carry the information signal and travel thousands of miles of optical fiber, its path must be kept crystal clear, including fiber optic connectors in the network.
What part of a fiber optic connector should be cleaned, exactly?
OK. now comes the critical part. What part in the fiber connector needs cleaning, exactly? the short answer is the ferrule’s body and its end face. but what exactly is a ferrule?
Ferrule is a cylindrical and also the most critical part in an optical fiber connector. it is usually made from stainless steel or Zirconia.
Zirconia is a type of white colored ceramic which is an extremely refractory material. it offers chemical and corrosion inertness to temperatures well above the melting point of alumina. Zirconia is the preferred material for high quality fiber optic ferrules.
Ferrules have a tiny hole in the center which holds optical fiber in place. Then the fiber is scribed and precisely polished to flush with the end face of the ferrule.
Two fiber connectors can then mate to each other with a mating sleeve. when mated, two ferrules’ end faces contact each other perfectly and thus pass light from one fiber to another.
Ferrules get dirty from dust, stain and debris made by constant plugging and unplugging after having been used for a while. these contaminations will block the light path and thus seriously reduce the light power and may disable the network connection.
Is there only one method for fiber connector cleaning?
There are many different ways to clean a fiber optic connector. They are not exclusive but rather complementary to each other. when one method failed, you can always try another method. and that is why there are so many fiber optic supplies for cleaning fiber connectors available on the market.
1. Air spray. Air dusters are used to blow loose particles from optical fiber connector end face. Optic grade is more expensive. Air spray is a non-abrasive fiber optic cleaning method.
2. Lint-free wipes with isopropyl alcohol. the operator folds the lens paper (such as the lint free wipes) into 46 layers and lay it flat on a table. He then holds the connector vertically straight and cleans the end face in figure 8 motion.
3. Reel fiber optic connector cleaners. Connector reel cleaner is a dry cleaning method with a quick, reliable operation and uniform results. They use 2 micrometer weaved polyester cloth to clean optical fiber connectors. this is an abrasive fiber optic cleaning method but pad underneath cleaning cloth mitigates this significantly.
4. Stick or swab type cleaners. these specially built Cletop sticks come in 2.5mm and 1.25mm versions. They are designed for dry cleaning fiber optic connector mating sleeves, bulkhead adapters and receptacles.
5. In-situ cleaning. this semi-automated fiber optic cleaning method is specially designed for fiber optic connectors plugged in patch panels and hardware devices.
6. Pre-saturated or soaked wipes. Pre-saturated wipes are good for cleaning glass fiber or connector end faces. They are available in a convenient pre-saturated towelette. the towels are durable and non-linting. Pre-saturated wipes are a convenient option for field use.
Fiber Optics for Sale co. offers all types of fiber optic supplies for fiber optic cleaning.
Fiber Optic Cable
360 days
Think of discrete packets of light propagating through the waveguide. Most of the light rays making up these packets will be guided through the waveguide within the limits of its physical boundaries. The path of light will follow in a straight line, bouncing off the side of the waveguide as a result of reflection. some of the rays will get loss in the waveguide, but most will continue to reflect.
Optical Fiber is a very thin and flexible medium having a cylindrical shape. It is the light equivalent of microwave wave-guide. The fiber waveguide is constructed of two layers of glass or plastic. It consists of following three sections:
- The inner most layer or the core, is where the light travels. It is made of glass or plastic and has refractive index.
- The fiber core is surrounded by a transparent sheath called cladding. It is a glass or plastic coating having optical properties much different from those of the core. The refractive index of cladding is lower than fiber core and denoted by c. this layer is kept thick enough about one-tenth of the cross-sectional area in order to provide isolation.
- These layers are protected by an outer section called jacket or coating. It is made of polymer or any other material that provides protection against moisture, crushing and other environmental dangers.
The core acts like a continuous layer of two parallel mirrors. It has higher refractive index then cladding ie. f > c which results in total internal reflection. A signal is first encoded into light beam which is then passed in between the boundaries and propagated as a result of multiple internal reflection.
If the light wave enters at one end of a fiber at an angle less than acceptance angle then it strikes the fiber cladding medium at an angle more than critical angle and is totally reflected the totally internal reflected light stroke the opposite wall at an angle more than critical angle and is again totally reflected this process continues through out the length of the fiber and emerges from the other end without appreciable loss of energy
Fiber Patch Cord Important Indispensable Part In Fiber Optic Link
412 days
Fiber JumperProfile:
Fiber patch cord also is called fiber jumper andfiber patch cable .That is the fiberdirectlyconnectedwith the desktopcomputer or device ,to facilitatedeviceconnectivity andmanagement.Tt isused as jumper cablesfrom the devicetotheoptical fibercablinglink.
Structure of the fiber pach cord:
Fiber patch cord is similarwith coaxial cable,just have notMeshshield.in theCenter of the fiber jumper istheglasscoreoflight propagation .Inmultimode fiber,thecore ‘s diameter is 15m50m,broadly in line withthethickness ofa human hair.Single-mode fibercorediameter is 8m10m.Outside the coresurrounded bya layer oflowerrefractiveindexthan thecoreof theglassenvelope, so thatthefiberremained atthecore.and thenthe outsideisa thinplasticcoatused to protect theenvelope.
FiberjumperCategory
Fiber jumpersaccording tothedifferenttransmission mediacan be divided intocommonsilicon-basedoptical fibersingle-mode,multimodejumpers,aswellasotherfiber jumperssuch asplastic,such asthetransmission medium;connectorstructurecan be divided into: FC jumpers,SCjumper,STjumpers,LCjumpers,MTRJjumpers,jumperof MPO, MUjumper,the SMAjumper,FDDI,jumper,theE2000jumper,theDIN4jumper,the D4jumperand sovariousform.The more commonfiberjumpercan also bedividedintothe FC-FC,FC-SC,FC-LC,FC-ST,SC-SC,the SC-ST.
Single-mode fiber(Single-modeFiber):Fiber Jumperwith yellowconnector andprotective sleeveblue;longertransmission distance.Multimode fiber(Multi-modeFiber):Thegeneralfiber jumperswith orangeand somegrayfittings andprotectionapplybeigeorblack;transmission distanceisshort.
TheNote forFiberusing:
Fiber jumpersat both ends oftheoptical moduletransceiverwavelengthmust be consistent,that isthe two endsofthefibermustbethesamewavelengths of lightmodule,a simpledistinctionisthecoloroftheoptical moduleto be consistent.under normal circumstances,theshort-waveoptical moduleusingmultimode fiber(orangefiber),andlong wavelengthmodules usesingle-mode fiber(yellowfibers),in order to ensuretheaccuracyofthedata transmission.Fiberdo notuseexcessivebending andcircling, this willincreasethe attenuationoflightduring transmission.Must use theprotective coveraftertheuseoffiber opticjumperfiberconnectorprotected fromdust andoil willdamagetheoptical fibercoupling.Iffiber optic connectorsaredirty, thenyou can usea cotton swab dipped inalcohol to clean,otherwise it will affectthecommunication quality.
Characteristicsoffiber jumpers:
(1)lowinsertion loss(2)and good repeatability(3) Return Loss(4)Mutual insertperformance(5) good temperature stability
Applicationoffiber opticjumper:
Fiber Jumpers products are widelyapplied to:thecommunications room,fiber to the home,local area networks, fiber opticsensors, optical fiber communicationsystems,fiber optic connectorstransmission equipment,anddefensereadiness.Applicable tocable televisionand telecommunications networks, computerandfiber-optic network,andoptical testequipment.Subdivisiondownis mainly used inseveral ways.Anoptical fiber communicationsystem(2)optical access network3fiber-opticdata transmission(4)fiber optic CATV(5)a local area network (LAN)6.Test equipment7fiber optic sensors
How Do Fiber Optic Connectors Work?
414 days
The history of fiber optic telecommunication deserves a book by itself since it took several generations to get the industry today.
Optical fiber is a long thin cylindrical fiber made from glass or plastic, as tiny as one tenth of a human hair. A standard telecom optical fiber is composed of three cylindrical layers, counted inside out: fiber core (diameter 810um), cladding (diameter 125um) and buffer coating (diameter 900um).
Fiber core and cladding is made from glass or silica. Fiber Core and cladding layers work together to confine the light inside the core without leaking. Fiber buffer coating is made from acrylic or plastic and provides handling flexibility and physical protection for the fiber.
Optical fibers utilize an optical phenomenon called total internal reflection. when light is injected into the fiber from end face, it is confined inside the core without leaking outside and losing its energy.
Then light is digitally modulated to represent 1 and 0 just like a computer, so information can be carried from one site to another site which may be from San Francisco all the way to new York.
What are fiber optic connectors and how do they work?
Now you know how optical fibers work. so what is a fiber optic connector and what’s its function in a fiber optic telecommunication network?
Put it simple, a fiber optic connector’s function is just like an electric power plug, it connects light from one section of optical fiber to another section of optical fiber.
Since optical fibers are so tiny, fiber optic connectors have to be made with high precision, at the scale of 0.1um which is one hundredth of a human hair.
Fiber optic connectors align two fibers end to end so precisely that light can travel from one fiber into another without bouncing off the interface and loss its signal.
Besides, fiber optic connectors provide cross connect flexibility for the telecommunication network. so a complicated computer network could be made modular and easy to manage.
Just like any other connectors used in electric industry, electronic industry and computer industry, many different kinds of fiber optic connectors were invented along the development of fiber optic communication industry. some of them once were very popular in the industry and now have served their purposes and are fading away.
The most popular fiber optic connectors used nowadays are SC, ST, LC, FC, MTRJ, SMA and a few of other less popular ones. Sure you will see new connectors invented with the progress of this industry.
What is Fiber Optic Cleaving?
457 days
Fiber optic cleaving is the process to scribe and break an optical fiber endface. Fiber optic technicians need some training in order to gain the skills necessary for best possible results.
The goal of fiber cleaving is to produce a mirror like fiber endface for fiber splicing – either fusion splicing or mechanical fiber splicing. incorrect or pool cleaving techniques will result in lips and hackles which makes good fiber splicing impossible. A bad cleaving usually has to be redone.
The tools needed for fiber cleaving are called fiber optic cleavers or fiber cleave tools. There are two types available on the market: high precision fiber cleaver and field fiber cleaver.
High precision fiber cleavers cost from $1,000 to $5000 dollars while field fiber cleavers cost from $100 to $500 dollars. High precision fiber cleavers are usually used for fiber fusion splicing applications while field fiber cleavers are mostly for field installable fiber connector applications.
The design of fiber optic cleavers varies among manufacturers such as AFL, Corning, Fujikura or York. But the working principle is the same. Here I describe a typical work flow of optical fiber cleavers.
Step one: Strip the fiber to its cladding size, the standard optical fiber cladding size is 125um. The strip length depends on your application.
Step Two: clean the fiber with lint-free wipes moistened with isopropyl alcohol.
Step three: Place the stripped and cleaned bare fiber into the fiber cleaver
Step four: Scribe the bare fiber with either a cutting wheel or a blade
Step five: Break the fiber with the built-in mechanism on the cleaver
Step six: Remove the fiber scrap and put it into a fiber disposal unit
This semi-automated process produces high quality cleaving in minimum steps. It has been used widely in the fiber optic communication industry.
Avago offers QSFP+ modules that interoperate with SFP+ devices
462 days
Avago Technologies (NASDAQ: AVGO) has unveiled a pair of QSFP+ optical transceiver modules that offer interoperability with fielded SFP+ modules. The new pluggable, parallel optical QSFP+ eSR4 transceiver can address both 40 Gigabit and 10 Gigabit Ethernet applications with a verified link distance of 400 m. meanwhile, the QSFP+ iSR4 modules enable interoperability to 10G SFP+ links up to 100 m using OM3 multimode fiber (MMF) and 150 m using OM4 MMF.The new modules are designed to offer data center operators the flexibility to reuse their current 10G infrastructures when upgrading to 40G.The Avago QSFP+ eSR4 modules integrate four 10G lanes in each direction to increase bandwidth within a line card by more than three times while using 50 percent less power than that of a one-lane SFP+ module. The QSFP+ eSR4 modules enable the development of top-of-rack, blade, and modular switches with up to 44 QSFP+ ports per line card. This provides 176 10G-channels with QSFP+ instead of the 48 SFP+ channels available today. QSFP+ eSR4 modules can be used for both high-density 10G and 40G aggregated Ethernet applications, providing more flexibility to connect to different levels of switches, reducing latency, and increasing port density with lower power consumption per lane, Avago says.The QSFP+ eSR4 extends reach to 300 m with OM3 MMF and 400 m using OM4 MMF. Avago expects to sample the QSFP+ eSR4 modules by this summer. The QSFP+ iSR4 modules are now in production.“We have worked closely with Avago to test a wide array of Corning Cable Systems’ fiber-optic cables that contained Corning ClearCurve OM3 and OM4 multimode fibers with their parallel optic transceivers, giving designers the flexibility to develop innovative data center applications,” said Doug Coleman, manager, technology and standards at Corning Cable Systems.“Together we verified that the interoperability of the Avago QSFP+ eSR4 modules meets link distance specifications for both 10 and 40 Gigabit Ethernet applications.”Avago will demonstrate the QSFP+ iSR4 and eSR4 modules, along with its portfolio of high-speed optical fiber products, in Corporate Village booth #1357 at OFC/NFOEC.
For more information on optical transceivers and suppliers, visit the Lightwave Buyers Guide.
Multimode Fiber Patch Cable For Higher Data Throughput
478 days
Information available at our fingertips in form of digital data today has swelled up to levels that had never been before. At the same time, real time communication has exponentially increased to extremely high levels. a whole class of applications have emerged that demand for transmission of high speed data. Necessity is the mother of invention – optical fiber networks have been invented and deployed to solve the problem of high volume data exchange. and multimode fiber patch cables have become the first choice among the different connectors of the wired carriers with endpoint devices.
What are the speed-hungry and volume-hungry data centric applications that have created this entire demand? Some examples of these applications are the Internet, the local area multi-computer networks, the telephone networks and the ATM networks. and there are many more applications with intense hunger for fast communication resources. for all practical purposes, these communication channels require a high speed network that can carry enormous volumes of data with minimal attenuation and extreme accuracy. The modern fiber optic cable technology provides exactly this kind of communication.
The multimode patch cables are used to connect this data transmitted over the network to the devices that they target to cater. these patches can also be used to connect the two loose ends of two fiber optic cables. The patch cables have to be multimode if the requirement is to support multimode optical fibers.
What is a multimode cable in the context of fiber optics? a multimode is one in which multiple packets of data can be simultaneously carried along the wire. The result is that the network can carry a number of data packets at any given instant of time. The multimode mainline network cables are typically short in length since the target with these cables is to support high speed and high power multiuser systems in a localized sense. The patches are compatible with the network cables to enable the system remain aligned with the network objectives. As a result the multimode patches support multiple user applications transferring data at the same time, as well as retain the qualities of regular single mode patches such as the high network speed, low network hindrances and low external interferences.
It is also interesting to note that the end point devices that these patch cables connect can be heterogeneous in nature. The aperture that the end point device requires and kinds of applications supported might be diverse. so there are a number of different kinds of multimode fiber patch cables that can be used based upon the requirements. and depending upon the exact reason that you need to install the patch on your optical network, you shall have to select your patch and go ahead with the required installation.
Tips to Fusion Splice Your Fiber Optic Cable
630 days
Talking about splicing fiber optic cable, you will find two different types of splicing processes. Fusion splice will be the first type and the second one will be mechanical splicing. In this article, we are going to talk about fusion splicing since this is the most recommended type due to the less risk of insertion. Here are some tips in splicing your cable by using this certain method.
You have to notice first that fusion splicing is generally a bond of two or more optical fiber that joined together permanently by welding. You need to provide splice cleaver if you want to have less problems of light loss or reflection. Making such a poor spice causes the ends of the fiber could not melt together properly, and surely it could cause problems.
To begin splicing your cable, you can start to prepare the fiber first. Strip all the coatings, tubes, as well as jackets of your cable and make sure that you have only bare fiber left. clean all of the filing gel from the fiber by using gel cleaner. make sure that you are cleaning it well since clean environment will be great to support better connection.
Tips to Fusion Splice your Fiber Optic Cable
Second, you can cleave the fiber. You need to provide a good cleaver to get an excellent splice. You can align the fibers either automatically or manually when you fusing the fibers together. it will be depended on the type of your machine. An electrical arc usually will melt the fibers together and it will create permanent welding for the two ends of the fibers.
Third, you can take heat shrink tubing to protect the fiber. it will be perfect to keep the optical fiber of your cable safe from any elements that might create breakage.
Now your cable has been spliced successfully. In order to get maximum splicing result, it will be better for you to provide some supporting tools in great quality. therefore, you will not feel disappointed with the splicing result of the cable.
Tips to Fusion Splice your Fiber Optic Cable
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Can anybody let me know that what is the bandwidth value of a single mode optical fiber?
685 days
I am actually from the field of optical fiber testing and QC. Its my constraint that I should have some basic knowledge about the working and specifications of Optical Fiber.