Category: Fiber Transceivers

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

How to Use OADM in WDM Network ?

by http://www.fiber-mart.com

OADM is a cost-effective and easy to use passive fiber optic component, which can provide easy to build and grow connectivity environment for WDM network. The optical add-drop multiplexer is one of the key devices to implement such optical signal processing. Use of OADM makes it possible to freely add or drop signals with arbitrary wavelengths over multiplexed optical signals by assigning a wavelength to each destination. In this article, let us introduce how to use OADM in WDM Network.
Inside an OADM
A traditional OADM consists of three parts: an optical demultiplexer, an optical multiplexer and between them a method of reconfiguring the paths between the optical demultiplexer, the optical multiplexer and a set of ports for adding and dropping signals. The multiplexer is used to couple two or more wavelengths into the same fiber. Then the reconfiguration can be achieved by a fiber patch panel or by optical switches which direct the wavelengths to the optical multiplexer or to drop ports. The demultiplexer undoes what the multiplexer has done. It separates a multiplicity of wavelengths in fiber and directs them to many fibers.
Main Function and Principle of OADM
For an OADM, “Add” refers to the capability of the device to add one or more new wavelength channels to an existing multi-wavelength WDM signal while “drop” refers to drop or remove one or more channels, passing those signals to another network path. The OADM selectively removes (drops) a wavelength from a multiplicity of wavelengths in fiber, and thus from traffic on the particular channel. It then adds in the same direction of data flow the same wavelength, but with different data content. The main function of the OADM function is shown in the following picture. This function is especially used in WDM ring systems as well as in long-haul with drop-add features.
How to Connect OADM With WDM MUX/DEMUX
In most cases, OADM is deployed with CWDM or DWDM MUX/DEMUX. It is usually installed in a fiber optic link between two WDM MUX/DEMUXs. The following picture shows a CWDM network using a 1-channel dual fiber OADM between two CWDM MUX/DEMUXs. Signals over 1470 nm are required to be added to and dropped from the dual fiber link. On the OADM, there is usually one port for input and one port for output. The OADM can be regarded as a length of fiber cable in the fiber link. The point is the one or more strand of signals is added or dropped when the light goes through the OADM.
Summary
OADM is still evolving, and although these components are relatively small, they are immeasurable in the future. Optical Add-Drop Multiplexer (OADM) is used for multiplexing and routing different channels of fiber into or out of a single fiber. The CWDM OADM is designed to optically add/drop one or multiple CWDM channels into one or two fibers.

SC Fiber Optic Cable Connector Overview

by http://www.fiber-mart.com

The SC (Subscriber Connector) style has numerous types of standards recognizing simplex and duplex connectors and adapters. Standards recognizing the SC are FDDI, Fibre Channel, broadband ISDN, ATM and Gigabit Ethernet.
As you can tell the SC fiber optic connector has a square style front face and is easily confused with it’s smaller relative the LC connector. Let’s take a look at some of the advantages of the SC connector.
Available as a simplex connector that can be converted to a duplex connector using a clip.
Recommended by a large number of standards.
Offers pull-proof feature.
Great packing density, design reduces the chance of the fiber face damage during connection.
Keyed, low loss, pull and wiggle proof.
Terminated using quick cure epoxy, cleave and crimp and hot melt.
Typically what you’ll find at a subscribers location is the bulk horizontal or backbone cable side ends it’s run in the facilities telecommunications closet. Your SC connectors will then be managed in a fiber optic enclosure. Let’s check out one of my favorites by Corning.
Then the information technology manager, will manage his end using fiber optic patch jumpers that plug into an adapter panel that sits in the fiber optic enclosure.
The SC interface is very commonly used when using media converters to convert copper to fiber, then fiber to copper. The big disadvantage of the SC interface is it does not feature an SFF (Small Form Factor) design.
The SFF design commonly uses the LC interface, so if you have an application where the backbone cable needs to be plugged directly into a switch the LC connector will be required. It’s still recommended that you use a fiber enclosure, you could just get a fiber jumper with SC on one end and the LC on the other.

Pulling Fiber Optic Cable – Tips and How To Advice

by http://www.fiber-mart.com

Pulling fiber optic cable takes a lot of preparation. Without the right tools and knowledge, you can have a big mess on your hands.We’ll go over some of the common steps to get you ready to make the pull.
1) Measure twice cut once:
First and foremost, get the correct measurement. An easy way to do this would be to fish some pull string through your conduit. Make sure to follow the exact path the fiber will take, end to end. Once your string is all the way through, attach a heavier rope to the end, pull it all the way back and measure your string. Leave the rope in place, you will be using this to pull your fiber through later. (Tip: Always add at least 15ft to the final number. It may cost a little more, but can save you a lot of time and headache if you come up a few feet short. It is also a lot easier to work with the cable if you have some slack, vs a cable that barely reaches).
2) Plan your Run:
Buildings- Although it is not necessary to run the fiber through innerduct, many people prefer this to keep it clean and professional looking. If you prefer not to use innerduct, try to keep your pulls as straight as possible. Pulling diagonal is OK, but it will make for a neater appearance if your fiber is running parallel. Get it done right the first time. If someone is unhappy with the appearance, it will take much longer to correct, or re-pull the fiber. (Tip: Never pull around corners, even if you have a helper. You should always pull out the excess fiber to the corner, laying it down in a figure 8 pattern as your doing it. Then flip the whole bundle over and continue to pull on the other side).
Conduits- It is important to plan ahead, especially if your planning on pulling the fiber through underground conduit. Just like measuring the fiber, it’s very important to get this done right the first time. A general rule of thumb is to use a 1.5″ to 2″ conduit for the fiber pull. If your running long distances, or using a thick armored fiber, you may want to increase the size to 4″. It may also be a good idea to plan ahead and install a second conduit if you plan on future expansion. (Tip: Minimize the number of bends in your run. The fewer bends there are, the easier the pull will go. If you can’t get around it, install junction boxes. Also make sure to protect the fiber by putting plastic bushings on the end of the conduit).
3) Which Jacket is Right?
Outdoor – Outdoor fiber is used for all outdoor applications (except direct burial). It is flooded with a water resistant gel, which means it can be run in buried conduit. But that also means there is a 50ft limit to being run indoors due to Fire and Safety codes. For direct burial applications, we suggest you use an armored fiber. If you need to suspend the fiber for arial applications, you can buy the fiber with a messenger attached, or buy it separately and and attach it yourself.
Indoor – For indoor applications, you need to use a Plenum rated fiber. Plenum fiber complies with all Fire and Safety codes.
Indoor/Outdoor – For applications you need to run the fiber indoors and outdoors, you should use an indoor/outdoor rated fiber. This fiber can be run in underground conduit, and doesn’t have the 50ft limitation for indoor use. A great all around fiber.
4) Pulling the Fiber:
Communication is Key
Pulling fiber almost always requires at least 2 people, so communication is very important. Most fiber runs are a few hundred feet or more, so yelling back and forth isn’t an option. What to do? Walkie Talkies can be a great way to keep in touch with the guy at the other end of the cable. Get some with wrist straps or a belt clip so you don’t have to constantly pick it up off the ground.
Lube it Up
Make sure you properly lube the fiber during the entire run. You will want to start off with a generous coat on the pulling eye and mesh. It would be a good idea to stop from time to time and apply more lube to the fiber as you pull. Always use lubricant that is designed for cable pulling, not just anything off the shelf. If you use the wrong type of lube, it may damage the jacket of your fiber, or other cables around it. It can also clog up the conduit once it dries. Cable pulling lube is designed to resist freezing and clogging.
 Use the Right Rope
We recommend using a 1/4″ to 1/2″ thick pull rope, not pull string. You want to minimize the amount of stretching during your pull and string isn’t very good at doing that. Stretching can make pulling your fiber very unstable.
Pulling Eye Removal
Never use a knife or blade to remove the pulling eye. This can damage the jacket of the fiber, or worse, the fiber itself. Always use a pair of electrician scissors.
Stay up to Code
Honesty is the best policy. The NEC requires that cables used in premises, both commercial and residential, be “listed for the purpose” by a Nationally Recognized Test Laboratory (NRTL, pronounced “nurtle”).Always obey all fire and building codes. Never try to cheat the system just to save a buck, especially when peoples lives are at risk. If plenum rated fiber is required, use plenum rated fiber. It’s the right thing to do.
5) Pre-Terminated Fiber Optic Cable
The greatest thing to happen since sliced bread. Pre-terminated fiber optic cable assemblies save you time and headache. No need for expensive tools. No need for testing. Our pre-terminated fiber comes to you on a wooden spool, with the connectors already assembled on the fiber. We have the connectors staggered by 1/2″ to make it easier to pull through conduit or innerduct. The pulling eye is very strong and wont break on you. Test results are included. It doesn’t get any easier than this.

Everything you need to know about fiber optic cables- Including OM5

by http://www.fiber-mart.com

You’ve started a project to upgrade your network but not sure of what fiber cables you need. Should the cables be single-mode or multi-mode? Is there a specific length or speed needed? All of these questions are great to ask as you prepare your network project and think of future upgrades. Here is everything you need to know about fiber cables including the newest fiber type, OM5.
There are primarily two types of fiber optic cabling in the IT space.  Those two types of fiber optic cable are single-mode and multi-mode.  An optical fiber cable is constructed of a core (inner layer), cladding (layer around the core), and jacket (coating around the cladding).  Some layers of protective sheathing are added depending on the application and environment.
Single-mode fiber optic cables have a typical core size of 8.3 to 10 microns (in diameter) and a cladding size of 125 microns.  Single-mode cables are normally used in long distance applications with lasers for the optical transmission devices.  OS1 and OS2 are the standard types of single-mode fiber cables.  Both types of fiber cables are built to perform between 1310 nm and 1550 nm, but the OS2 types of cables have a better transmission performance especially over longer distances.
Multi-mode fiber optic cables have a typical core size of either 50 microns or 62.5 microns.  They have a cladding size of 125 microns.  Shorter cables distances, especially in data centers, are common uses for multi-mode cables.  Multimode cables are typically manufactured to certain specifications and are classified by Optical Mode categories.  These Optical Modes are known as OM1, OM2, OM3, OM4, and OM5.  OM1 fiber optic cables have a 62.5 micron core size.  All the other OM types listed below have 50 micron core sizes.
OM5 is the newest type of multi-mode fiber optic cables, and it is backwards compatible with OM4.  This type of fiber was formerly called Wideband Multi-mode Fiber.  OM5 is constructed to perform outside the normal operating bands of typical multimode cable.  It can support wavelength division multiplexing (WDM) between the wavelengths of 850 nm and 953 nm.  OM5 fiber cabling can transmit at least 4 wavelengths in the 850 nm to 950 nm range.
OM4 fiber optic cables are a fairly new type of fiber cables as well.  This color of fiber cables has been used for the past couple of years in Europe.  The reason for this was mainly to distinguish between aqua OM3 cables and aqua OM4 cables.  The new violet color of cables helps with this quick distinction.

The Benefits of Using OM1 When Setting Up Your Network

by http://www.fiber-mart.com

OM1 Cable with Orange Jacket
When using fiber optic cable, the information you are sending from one computer to another can get there faster. This is because you are sending the information throw glass. Glass has no restrictions and can allow what is sent to travel long distances and at higher bandwidths than conventional wire.
Of course, there are different types of fiber with data rates that differ, as well, not to mention the distance is also different. Some cables only allow for certain distances, while others can go much further. The base way to consider what type of cable you need is to know what type of network you are setting up.
In order to help you with picking the right cable, I have written a series of four blogs that will cover each type of fiber optic cable we carry, and give you the benefits, as well limitations of each type, so you can judge which one is best for you. The type of cables we sell include OM1, OM2, OM3, and OM4.
In this blog, I will discuss OM1, as this in the first of its kind we sell. As with any type of medium you use, there are variables to consider. These include the fiber transceiver, wavelength, cable type, core size of fiber (micron), and distance.
In general multi-mode, fiber optic cable can deliver up to 1 GB/s. This type of cable is good for up to 2 km. You will find its operating wavelength to be about 850nm and 1300nm. If you are using the wiring at distances of 100m, the bandwidth is unlimited.
With OM1, the data rate is 1GB at 850nm. It’s core size is 62.5 microns. This is why OM1 fiber optic cable is used when building tight space networks, as it can travel up to 300m.
OM1 cable easily supports applications ranging from Ethernet at 10 Mbit/s to 1 Gbit/s. OM1 has been know to support 10 Gigabit Ethernet at a length of 33 meters. Its core size were great to use with LED transmitters.  OM1 is best used to build short-haul networks, local area networks (LANs) and private networks.
OM1 cable can be recognized by  its yellow jacket.
If you are interested in purchasing this cable, go to fiber-mart.com and order yours today.

8 Steps to a Successful Network Cable Infrastructure

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n our last blog post we covered the use of balanced STP (Shielded Twisted Pair) and UTP (Unshielded Twisted Pair) to minimize the effects of RFI (Radio Frequency Interference) and EMI (Electromagnetic Interference), along with crosstalk that can take place between wire pairs carrying dissimilar data.
Because STP is not as common in today’s networked environment,we’ll reference this discussion on UTP only. We’ll also look at some of the basic issues with respect to the proper installation of UTP, such as Category5e, 6, 6e, and 7. This blog article builds on the information contained in our recent blog articles so be sure to have them handy if you need to review.
When we speak of installation with regards to UTP, we’re concerned with the potential for physical changes. Preserving the integrity of our cable(s) will give our network the stability and ongoing support it needs to maintain data rates of 1 Gbps (Cat5e) to 10 Gbps (Cat6, 6e, and 7).
The first place to begin in our effort to avoid problems is in how we install them.
Remove the cable from the spool or pullbox carefully to avoid twisting and kinking. Either one can change the outer dimension of the cable as well as how the conductors twist around one another within it. Kinks can flatten the cable, thus altering its electrical properties. This can adversely affect performance.
Feed cable trays, sleeves, and conduits with care to avoid damaging the outer sheath. Lack of care can also scrape the insulation from one or more conductors within the jacket causing potential short circuits.
Be sure not to pull Cat5e, 6, 6e, or 7 with more than 25 lb. of  pulling force for every 4-pair. To exceed this pull force has the potential to change the inter capacitance and inductive properties of the cable twists which can change the way it transports data. It also can snap conductors within it, in which case wire pairs may have to be substituted or a new cable installed.
Do not exceed a bend radius of 4 x the cable OD (outer dimension). For a  4-pair UTP cable, 10 x the cable OD for a 25-pair backbone cable. Tighter bends can and often will cause changes in the outer dimension of the cable thus causing it to change how it transports data.
Maintain the tight twist of a UTP cable right up to the point of termination at the jack or plug assembly. This will assist in your effort to maintain the rated specification of the cable.
When horizontally hanging UTP cable,maintain a maximum of 4 ft. between hangers. Cable sag should be maintained from 4 to 12 inches. When cable sag exceeds 12 inches, there’s a strong chance that the distance between hangers is greater than 4 in. If cable sag is less than 4 inches, it could indicate that the cable may be pulled too tightly.
When working in return air returns(plenum spaces), use plenum-rated cable because the insulation will not support a flame nor will it emit toxic fumes in the presence of one. Regular non-plenum UTP cable, however, is flammable and it will spread the fire when exposed to it. In addition, it will emit toxic fumes when it burns, and that can cause injury and death.
When binding cable bundles with wireties, do not pull them too tight as it will pinch the outer cable sheath thus causing potential problems with effective bandwidth and data transmission rates. We will continue to drill down into the installation and care of network cable in my next blog post. Thank you for taking the time to visit our blog.