Welcome to Gaia! ::

Welcome to Lesson 8 part 1. In this lesson we will look at some of the requirements for good copper testing.


2: Testing Procedures.

Testing is defined as an organized, systematic method for verifying the performance and quality of the installed network. The testing process can be divided into three phases: visual inspection, performance testing and analyzing the results. We covered the visual inspection in a previous lesson and this is included as part of the certification you sign off when a site is registered with your name as the approved I&M trained engineer. Now we will look at the testing process.


3: Results.

There are several testers available on the market but in this lesson we will show screen shots from the two most common ones, as most testers have similar style interfaces. Calibration: Calibration on the Fluke DSX5000 is modular so each module that is used for either copper or fiber will have its own calibration date. This can be accessed through the tools menu and then by clicking on module. This calibration date is the date the unit is calibrated from and that period of calibration is for one year. If using the tester near to the end of that period it will let you know that the renewal date is imminent. The calibration date is shown on the test report and can be reviewed by your customer and could be legitimately rejected if it is not up to date. The same applies if submitting results for a CommScope warranty. Out of calibration - results are invalid! Time and date: Don't forget to check date and time. That might sound obvious but if that is wrong and the results are submitted to the customer showing that the testing was allegedly completed at 3.00am in the morning, when it was actually done in the day, the results could be considered invalid. Setting up the project: It is easier to set a project before arriving on site if possible, as testing is usually done at the end of the project when time is shortest, or appears to be! This would include the name of the project, the cable type, the outlet configuration TIA-568A or 568B and the cable 'id' setup. The cable setup usually asks for the first 'id' and the last 'id'. Some testers can be set so that if you set 1A as your first 'id' and 9D as the last, if would actually set up 36 tests because it would recognize there were 4 tests 1A to 1D through to 9A to 9D. Results: Most testers today allow results to be saved to a USB stick. The Fluke DSX5000 also has a 'cloud' based service called LinkWare Live that lets you manage certification jobs anywhere and runs on most PC-based devices. The tester will require a USB Wi-Fi dongle to be connected to it. Linkware Live allows 'projects' to be set up in the cloud from a laptop, PC or tablet etc and then these can be sent to the testers on site, as required. Other benefits include test sets automatically being updated with the latest software, but primarily and the main advantage from an engineer's perspective is that the results can be uploaded to the cloud. If working remotely there could be 2000 test results or more after a week's testing, and if the tester was stolen, would never be retrievable. Uploading to the cloud ensures the main office has instant access to the results and the engineer has confidence the results are saved.


4: Visual Inspection.

Visual Inspection: The equipment itself needs a basic inspection. The permanent link test adapter leads must be checked or, if in poor condition, replaced. There is nothing worse that being on site with a faulty lead and trying to nurse it through site testing. On the Fluke test equipment the RJ45 jack tips are rated to about 5000 insertions but the tips can be replaced providing the cords themselves are in good condition. On the Viavi Certifier testers, the whole lead, if worn, can be replaced fairly economically if required. Some manufacturers offer 'Gold support' where replacement leads are included in the annual calibration service.


5: Visual Inspection.

Before testing it is essential that the correct cable parameters are set, otherwise your results will be invalid. The screen here shows a Category 6A test but this is generic cable type and most testers have these standards based tests, either ISO or TIA, that are selectable. For warranty purposes though it is important to set the correct cable from the manufacturers list. SYSTIMAX cable is found under SYSTIMAX, not CommScope, so scroll through these to find the correct one. Finally check the settings are correct on the home screen. Remember for warranty purposes a 'standards' based test is not sufficient.


6: Testing Procedures.

The next step is to set the reference for the tester. You will have already set in the tester the category of test that you want to do. Connect the permanent link adapter on one unit and the channel adapter on the other. On the Fluke tester the permanent link head should be on the main unit, while on the Viavi Certifier it doesn't make any difference. Go into the set-up menu and find the 'set reference' setting. Follow the instructions and now you are ready for testing.


7: Channel Testing.

Channel testing is not often called for and if it is completed, the tests are not normally saved unless the client has requested them. The reason for this is, if any of the cords in the link are replaced, even with one of the same length, that test will not be reproducible. Prior to channel testing, channel adapters need to be fitted and the correct test parameters selected from the menu. The testers here are ready to test a Category 6 channel but the test cords being used in the testers need to be left in place at either end of the link under test, at the completion of the test. Do not use the same set of cords for all the tests. Those with good eyesight will see that Category 6A channel test heads are being used here in this image. This will not affect the result as Category 6A channel adapters are used in most modern testers, because they are backwardly compatible and also the first connector of each link is not included in the test results. If testing a GigaSPEED XL channel, providing everything in the link is to the same specification including the GigaSPEED XL patch cords and there is no more than 10m of stranded patch cords in the channel, SYSTIMAX guarantee a NEXT headroom margin of 6dB with 4 connections in the channel and 4dB with 6 connections. This can be seen on the performance tab of the results. Here is a screenshot of a short link tested using the channel test. The NEXT headroom figure here is 8.7dB, so pretty generous!


8: Testing Procedures.

Here are some practical recommendations when testing. Make sure that there is no active equipment connected at the other end of the link or channel being tested, or the tester could be damaged. If there is active equipment, arrange for it to be disconnected. Inform the user/owner about the ongoing testing activity, especially if you need to disconnect equipment. Disconnecting video circuits during a teleconference, for instance, will not make you popular! Cabling may receive interference from radios, but most testers have talk features allowing engineers to communicate over the link being tested, so use those in preference to cell phones.


9: Testing Procedures.

Always try and start the day with a tester with fully charged batteries. A unit that is running low on charge will just add more stress to your day. The Viavi Certifier units show the battery condition on both the main and remote unit. The Fluke DSX5000 only shows the battery condition on the main unit, but there is a method of checking the remote unit too. Turn on the remote test set and all the lights will illuminate. After 5 seconds they will all go out and then depending on the state of the battery either all or some will come on. This unit here is only showing two lights so really should go on charge before it fails.


10: Test Results.

Test results, once saved, are rarely seen by the engineers again, but they can be printed out in either summary or individual style and this is where the project information added prior to testing can be seen. Time and dates cannot be changed at this stage and this could fail a whole project if this information was wrongly entered. When testing, spending a little time before you begin, pays dividends at the end.


13: Marginal Results.

Now let's consider marginal results. A marginal PASS is considered a PASS by standards but it may be that your client or your company will not allow marginal passes. We have just seen the headroom margin with GigaSPEED so getting several marginal passes in a row is indicative of a poor installation procedure. Obviously each marginal pass can be analyzed by clicking the diagnostic tab to investigate the problem. If they are all in the same area or the same type of fault, then that becomes the first place to look. Another area to investigate before ripping out faceplates or panels is to re-check the test leads, adapters and plugs to ensure they are all in a good condition. Older testers used to display a 'marginal fail', but as far as TIA and ISO are concerned this parameter doesn't exist as the test either passes or fails.


14: That Completes This Lesson.

Welcome to Lesson 8.2 Fiber Inspection and Testing.


2: Causes for Network Failures.

Fiber optic communication most commonly works in duplex transmission by transmitting light to a receiver in one direction on a fiber and receiving transmitted light back to a second receiver on the second fiber. Most engineers can understand that and also the fact that anything in that light path will degrade the amount and quality of light, but fail to appreciate how easy it is for that path to become contaminated. Contamination of connector end-faces can have a significant impact on network performance, as applications that run over fiber have a power budget which becomes smaller the higher the speed of the application such as 10G Ethernet. This graph highlights a study that was undertaken by NTT, where they polled various network installers and owners and asked them what the primary cause of fiber network failures are, so when 98 percent of the installers responded that it was down to contamination on the end-faces of the fiber, it came as no surprise.


3: Fiber Cleaning Equipment.

Clean connectors are essential throughout the channel and if you are working with fiber termination or even basic fiber patching, understanding the need for this cleanliness is critical. Basic equipment should consist of fiber stick cleaners which are currently the most efficient dry cleaners available on the market. Stick cleaners have a small reel of cleaning tape inside them, and when the stick is compressed against the end-face of the connector, or in a bulkhead, the cleaning tape inside runs over the end-face, cleaning it. These are available for LC, ST or SC and MPO connectors. Another piece of essential equipment is a scope, either manual or electronic (if available). Electronic scopes can also record the details of each connector's cleanliness and be supplied as part of the customer's documentation. It is critical that all contamination is removed before patching, as any particles in the core area will reduce the transmission of light. Two other items that should be in an engineer's kit for advanced cleaning are as follows: Fiber optic cleaning fluid: this is preferred over Isopropyl Alcohol as it dries faster and with less residue; and cleaning sticks (like high grade cotton buds) in different sizes for 'wet' cleaning bulkhead connectors.


4: Illustration of Particle Migration.

Let's look at cleanliness as its not only contamination on the fiber core that is important. Debris elsewhere can also cause problems because when two connectors are mated together, the particles, especially larger ones, are very likely to 'explode' as the pressure is applied to them. This graphic shows a picture of a connector using a 400x microscope that had some fairly large pieces of debris on it. Watch what happens as the connection is made and then re-mated several times. A lot of the debris is spread everywhere like shrapnel on each mating. There is no pattern to where it's moved, but notice that debris at the beginning was not on the core, however it now shows up on the core where it will prevent the transmission of light. In addition, large particles can create barriers or air gaps between the connectors that prevent contact and therefore affect performance. Small particles also tend to embed themselves into the fiber surfaces, creating damage to the connector end-face.


5: Wet Cleaning Fiber Connectors.

Sometimes there may be a requirement to 'wet' clean a fiber connector. As mentioned earlier, alcohol, if allowed to dry by itself, will leave stains behind on the end-face. Fiber prep fluid doesn't do this and is safe on glass, ceramic, metal, plastic optical fiber, will remove uncured epoxies, is non flammable and kind to the environment. Perhaps it's time to upgrade your fiber optic cleaning kit? If cleaning a patch cord connector, use a lint free wipe, moisten it with fiber cleaning fluid and clean the end of the connector. The connector can then be 'dried' with a stick cleaner or using a 'tex' wipe or lint free cloth. When cleaning fiber connectors with dry wipes, it is quite common to see engineers wiping back and forth against the end of the connector. The correct way to clean a connector is to clean it in one direction on the wipe, then move it to another part and again wipe in the same direction, otherwise dirt will be put back on the end-face. Wet cleaning connectors in fiber shelves or cassettes where they cannot be removed easily, can be achieved using fiber cleaning sticks. These are available in two sizes, 1.25mm for LC connectors and 2.5mm for ST or SC connectors. Again these are made using special materials so do not attempt to use a standard cotton bud. Cotton buds are very hairy! Moisten the tip of the cleaning stick with fiber cleaning fluid (do not allow it to be dripping as this will cause problems) and insert it into the coupler of the shelf/cassette. Rotate the cleaning stick gently, as it is quite a tight fit, then remove it and discard, as you do not want any dirt removed to be put back on to the next connector. Dry the connector with another cleaning stick or a dry stick cleaner and check with a scope before continuing!


6: Inspect, Clean, Inspect, & Go!

The best way to test fiber is to assume that the connectors are dirty before starting. The test procedure should go like this: inspect, clean if necessary, inspect and then connect. At the panel, before connecting the fiber cord, the couplers on the fiber shelf or outlet must be inspected. If they are dirty they must be cleaned, then re-inspected before connecting. If testing a fiber panel, it would make sense to inspect the complete panel before starting testing. This may seem long winded, but at least this way it will make the testing thorough and give good results.


7: Multimode Fiber Inspection.

The relevant standard for optical fiber inspection is the ISO/IEC61300 series. For typical campus and building installations, the inspection of fiber connectors is easy to do using a fiber microscope. An ideal end-face is one that is clean and scratch-free. Here are some examples of unacceptable fiber end-faces and are typical of field terminated hand polished connectors and should have been failed at the inspection stage. This one has been damaged with a heavy cleave, while this second one has a shattered fiber caused by the termination. The fiber is broken inside the ferrule and this connector should be discarded and is not repairable. This end-face has a chipped fiber, but would transport light through it as the chip is outside the immediate core area. It is polished cleanly though and a poor cleave is the most likely cause. Lastly here is an over-polished fiber end, but it looks fairly good at first glance. On closer inspection it has a number of heavy scratches across the core area, most likely caused by over-polishing on the first of a two-part polishing process. It could possibly be repaired with a repair paper but is indicative of a poor polishing process by the terminator.


8: Inspection of Fiber.

We have just been looking at multimode connectors but when evaluating the end-face quality of single-mode connectors it is easy to see the difference. Here are a single-mode and multimode connector side by side. The single-mode is backlit allowing the 8 micron core to be seen, while with the multimode connector the backlit core can just be made out. The main difference between a single-mode and a multimode connector is the connector tolerance, and to some extent the cladding tolerance. Both connectors have a fiber cladding of 125 microns. However the alignment for a single-mode 8-micron core is critical as a micron of movement will impact the amount of laser light lost at the interface. For a multimode fiber this is not so critical, as it has a relatively large core area for light to excite and a few microns of alignment either way will not have the same impact. Surrounding the cladding is a layer of epoxy glue which holds the fiber in the ferrule. With the single-mode connector this can hardly be seen but is clearly visible in the multimode connector and shows the fiber is also marginally offset. This is why a single-mode connector is more expensive than a multimode one. If the single-mode fiber was used in the multimode connector and was fully offset, the 8 micron core would be offset by up to 4 microns, having a disastrous effect on the light transmission. This shows the importance of using single-mode connectors on single-mode fibers.


9: Common Contaminents.

Here are some examples of typical problems found during inspection. These dust particles are typical of a connector having been brushed against an item of clothing or dropped on a floor. Fingerprints are the culprit here, caused by the resultant grease or sweat, typically. Natural moisture from skin will leave a nice layer of contaminants on the end-face and is caused by careless handling of the connectors. These two images are taken using a different style of viewer and the complete end of the ferrule can be seen. These are badly contaminated and look more like a culture you might find in a laboratory. Any sort of sweat or grease from the finger will develop into images such as this and if dried as they will do in a warm communications room, the resultant contaminants might need wet cleaning to remove. Where Isopropyl Alcohol has been used incorrectly, it can cause more problems. This is a typical dried alcohol stain. So cleaning if not done correctly will also cause problems. There is a video in the download area of this lesson that explains the correct procedure for single fiber connector cleaning.


10: Losses & Testing.

As interface speeds have moved from 100Mbps to 10Gbps, and now 40Gbps and 100Gbps, the loss budgets for fiber optic links have become tighter and tighter. Because of this, in the early stages of the project, the designer will have had to calculate these losses using the SYSTIMAX Link Loss calculator. The results from this are then supplied to the fiber engineers so that when testing they can ensure the installed link or channel conforms to the designed attenuation specification. Higher performance equals lower allowable loss, so with such tight attenuation tolerances, even factory pre-terminated fiber cables and component interfaces need to be evaluated for cleanliness (dirt and dust) prior to connection.


11: Link Loss Calculator.

Let's look more closely at this link loss calculator and see how it works. A copy of this is available in the lesson download area. It's basically an Excel spreadsheet that allows you to put in all the components in the link and calculate the losses over it. The designer will have used this when checking the installation.


12: Link Loss Calculator.

Let's give it a run! In the cable type box there is a drop down menu so here we have selected 'LazrSPEED fiber with field termination @ 850nm'. The link is 200m long and the patch panels at each end have LC connectors, so we entered '2' there as that equates to 2 patch panels. Don't worry about the patch cords as that is all taken into account by the spreadsheet's hidden calculations. You can also see it has a box for loss test set uncertainty and SYSTIMAX allows us to enter 0.25dB there, which is generous, according to two of the major test set manufacturers, but that works to an installer's advantage though, as it gives extra margin. Looking to the bottom orange strip we can see the loss is already calculated there at 1.5dB.


13: Link Loss Calculator.

If we change those two LC patch panels to SC, the loss has increased from 1.50dB to 2.02dB. That is over half a dB, but if there were more than two SC connections in the channel those losses would increase much more than if LC connections are used. LC connectors have a much lower loss than both ST or SC and therefore when it comes to running long distances these are the connectors of choice. They are also the most common style of connectors found on 10Gb interfaces.


14: Link Loss Calculator.

In many installations today, fusion spliced pigtails are quite common. These need to be added into the calculations too, if used. By adding 2 to the quantity of splices box, our original LC link loss has increased from 1.50 to 1.81 which is an overall increase of 0.31dB, which again is very generous when most of today's fusion splices record a 0dB loss upon completion. This box must also be used if using pre-polished splice connectors such as QWIK connectors as they have effectively a mechanical splice at the back of the connector which must be taken into account. So now we can see how the calculations are made, let's continue on with the testing procedure.


15: Fiber Testing.

Standards have now introduced a requirement into the latest IEC and TIA test documents that introduces Encircled Flux (EF) metrics. This change is being driven by the recognition that loss budgets have diminished as data rates have increased, thus necessitating more precise measurements. Most new fiber test equipment comes with these EF launch cords as part of the kit, either included in the test leads or the test heads. These work by restricting the number of mode groups launched from the test cord to within EF specifications, ensuring that the resulting measurements are precise and repeatable.


16: Fiber Testing.

Let's now look at setting up the test equipment. The examples shown here are the Fluke Versiv and Viavi certifier, but most test sets have the same menu-type functions for setting the parameters and basic hardware. 1) No matter what tester you are using, the test cords must be checked before you start. Shown here are reference grade test cords one pair straight and the other with EF controllers built in. They should be in good condition with no kinks in them and should be fitted with dust caps. If the dust caps have been left off it would be advisable to check them with a scope, clean them then inspect them again to make sure they are actually clean. If the dust caps are on, preventative cleaning with a click cleaner is essential before starting. Remember the animation we saw earlier of connector contamination. You don't want to get any contamination between connectors.


17: Fiber Testing.

The next thing to do is set up the parameters. Most testers take you through the options. This screen shot all seems fine but these settings are not acceptable for a SYSTIMAX warranty. The correct fiber type needs to be set and in this instance it should be LazrSPEED 300, so select fiber type and go to 'manufacturers' and find the 'SYSTIMAX' options. Allow both units to stabilize for at least five minutes before starting to test.


18: Fiber Testing.

Now the test limits need to be changed. These will need to be entered manually so select the 'custom' setting and create a new one. We will create a new project and call it 'Cab 2 to Gatehouse'. Projects can be set up in advance, minimizing wasting an engineer's time on site, so all they have to do is find the correct project and start testing. The test parameters in this instance must be set according to the calculator spreadsheet we saw earlier, so the length here is 125m and we have LC patch panels on each end. The loss budget should be set to 'fixed'. Below this there are three options for setting the losses at different wavelengths. Remember that for testing horizontal MMF links, testing is required at 850 or 1300nm while for backbone and composite links it has to be tested at 850 and 1300nm.


19: Fiber Testing.

Set the loss according to the spreadsheet and press Done. Then add the 1300nm loss (if required) according to the fiber calculator. Click Done and the unit is set up for testing.


20: Fiber Testing.

One of the most common problems with fiber testing is setting up the reference correctly. To do this, most machines will walk you through the options so you do need to follow them. Press 'set ref'. Now, STOP. Have you checked your cords? Are they clean as they must be before you start. 2) Follow the on-screen instructions and connect the cords. 3) The screen tells you which way round to do so, and in this instance the red ends connect to the output ports. Once connected the tester lets you know the main and remote units are connected. Press Next. 4) The reference is set and now the loss of the additional jumper cords need to be verified. Follow the connection instructions and you will also need a single-mode coupler to connect the cords together. 5) Remember we discussed earlier that single-mode connectors and couplers are built to a higher tolerance than multimode ones, so by using a single-mode coupler here, will give the best results. 6) The losses of the cords are now shown and as these are within specification the link is ready for testing. 7) The diagram here on the screen is showing that the tester is ready to test the link. Just remember, do not remove the cords from the tester otherwise the reference will have to be reset. Remember for SYSTIMAX warranty purposes, SYSTIMAX parameters must be set. TIA an ISO ones are not acceptable.


21: Link Loss Calculator on the CertiFiber Pro!

The latest version of the link loss calculator is now included as part of the software on the Fluke Certifiber Pro. This includes the Ultra Low Loss OM5 fiber that was discussed in an earlier lesson. Setting up the test limits correctly will allow the pass / fail criteria to be set automatically when testing.


22: Link Loss Calculator on the CertiFiber Pro!

The software works by configuring a link based on the type of system and then number of connections in the link. Having selected the type of fiber i.e. Field terminated, InstaPATCH or ULL (Ultra Low Loss) the interface allows you to enter the number and type of connections, splices and also the jumper reference method.


23: Link Loss Calculator on the CertiFiber Pro!

Those of you familiar with the Fluke products will also be aware of Linkware Live that is a cloud-based offering allowing the test results to be uploaded via the Internet, from the test equipment on the job site. This can then be accessed by the project manager to download and store / distribute as required. This cloud service prevents results being lost when equipment is stolen or damaged, which is a technician's nightmare because of the time invested and consequential financial losses. Another option included with Linkware Live is that the project manager can also set up new parameters as required,


26: Multi-Fiber Inspection and Cleaning.

We have looked at single connectors but more and more data center type environments are using MPO, multi-fiber connectors with fibers in a single plug. Basically there are two sorts of MPO connector styles to be found, male and female! Of course they come in different densities, from 8 up to 72 fibers, but all in a single connector and the fiber cleaning and inspection procedures are the same for each. The female connector can be seen here and has two holes on either side of the fibers for alignment but is basically a flat topped connector. A tap on the end with a finger could cause contamination and will need cleaning! The male has two pins for alignment so the end-face is partially protected but at a first glance may be more difficult to clean and inspect! Single-mode versions of these have slightly angled head of about 8° so like the APC connectors we saw in an earlier lesson, give reduced reflections when connected, improving performance.


27: MPO to MPO Trunk Testing.

Testing of MPO trunk cables would be greatly enhanced by the availability of an MPO interface and OLTS equipment that could automatically test bi-directionally across the MPO interface. This is an example from Fluke that can test multimode and single-mode trunk cables with a choice of four selectable wavelengths. There is a bar graph on the screen and once both ends are connected, all the cores of the trunk cable connectors are displayed showing continuity and also if they are clean enough for the test to commence. If all is okay the test itself only takes six seconds, during which the polarity and power loss for each of the 12 fiber cores is displayed. Should any of the cores not pass the testing process because of a dirty connector end-face, the failed cores will be visible on the screen. This testing procedure negates the need for fanout cables being used at either end and any additional couplers, so greatly simplifies the testing process.


28: MPO/MTP Connectors: Fiber End-Face Condition.

For multi-fiber connectors, having the right inspection equipment is essential. Because the connector is about 10mm (3/8 inch) wide the viewer needs to be able to scan across the end-face checking each of the fibers. The scope being used here has a special tip on the end of the probe to allow the camera to be scanned across the X axis or the Y axis of the connector by using the adjustable controls, to visually inspect each of the fibers. This is a close up of just two of the fibers, looking like fried eggs against a very lumpy background. In order for the connector to be good, all of these fiber ends must be clean.


29: MPO/MTP Connectors: Fiber End-Face Condition.

Before and after inspecting the MPOs, they need to be cleaned. The best piece of cleaning equipment on the market is the stick cleaner as seen here. The cleaning stick is keyed to ensure the cleaning tip only fits one way onto the connectors and is able to clean both male and female ends by either using or removing the adapter on the end. This cleaner works in the same way as the other ones we have seen for single connectors except this one has a woven lint free tape that cleans the connector end-face. MPO connectors are either male or female, so this universal tool will cope with both. In a close up of the back of this module it can be seen that the connector is keyed, and as the cleaning probe is keyed as well it ensures that when cleaning male connectors, the tape cleans between the male pins without leaving any contamination on them. If wet cleaning is required, then use the appropriate cleaning stick and wipe it across the fiber array, top to bottom rather than side to side. If the array is side to side to you will just pass the contaminants from one fiber to the next.


30: MPO/MTP Connectors: Fiber End-Face Condition.

Careful cleaning of connectors and adapters is a top priority. It maximizes channel performance and can resolve many issues seen during system validation. Please review the videos in the download section of this lesson, that cover the cleaning of simplex and multi-fiber connectors.


31: That Completes This Lesson.

Welcome to Key Standards - Standards Bodies. As you will discover, there is no shortage of standards in the infrastructure market. In this lesson we will review the main standards bodies that are applicable to cabling infrastructure design and their inter-relationship and national relevance. Please note that each country may have its own standards and recommendations not covered in this course. The International standards are used as a basis to cover the global requirements. The US and Europe standards are used to illustrate how standards can differ.


2: Commercial Building Wiring Standards.

There are three commercial building wiring standards. Let's have a quick overview of them. ANSI/TIA 568 is the U.S. regional standard. Drafted originally in the late 80's, following EIA establishment of the TR-42 committee, with the first revision published in 1991. In 2000 the B revision sub-divided it into a number of parts and since then it has moved through a succession of major revisions, A through to C with parts 0 (Generic) and 1 (Office) being revision D. Between these revisions they have been updated where needed with addendums. The graphic highlights a key of these key dates in its evolution. ISO/IEC IS11801 is the international cabling standard that incorporates all variants of cabling types used around the world, titled Generic Cabling for Customer Premises. It was published in 1995 and Working Group 3 has undertaken a number of editions, 1 through and towards Edition 3.


3: Commercial Building Wiring Standards.

EN50173 is the European standard, which has been largely derived from IS11801. Each of these standards includes design and performance specifications for twisted pair, fiber infrastructures and connecting hardware within commercial buildings and campuses. IS11801 and EN50173 allow for more product variants because of their larger regional market differences. The designer may need to be aware of these differences in selecting cabling systems that comply with these standards. In this course we will focus on these three standards for the basis of design, highlighting the differences between them when applicable. It should also be noted that these three documents cross reference and refer to a whole plethora of other related standards documents.


4: Design & Installation Standards.

In addition to the three main commercial building wiring standards we have just seen, there are now a number of design standards published that cover more specific customer environments such as industrial, homes, data centers, building services and more. There is also a comprehensive series of installation standards that the designer will need to be aware of. These are shown here but will also be referenced more completely later in the lesson and throughout the course.


5: Design & Installation Standards.

So what do the three main building wiring standards 568, 11801 and 50173 include? Commercial building wiring standards cover the topology and structural hierarchy of network cabling. They also cover specifications for the medium through which data is transmitted, distances over which data can be transmitted, specification of both copper and fiber cables, hardware, cords and lastly specification and testing of cabling links and channels. Following are a few examples from the TIA and ISO standards. Remember the CENELEC 50173 cabling standard is very similar to that of ISO IS11801.


6: Wiring Standard Topics.

Let's start with a look at the ANSI/TIA 568 wiring standard and just one fundamentally important design topic it includes, topology. We want to demonstrate the relationship between the parts of the standard - that way you will make some sense of how the design standards for a given region relate to each other. The generic part of this TIA standard defines a high level design that is common to a number of the TIA standards below it, as shown by the arrow. So let's compare first the TIA568.0 topic of topology and its relationship when designing the topology inside an office using TIA568.1 below.


7: ANSI/TIA-568 Topology.

Fundamental to all three regional wiring standards is a hierarchical star topology for cabling and patching design recommendation. This graphic depicts the generic design layout from the latest version D of the ANSI/TIA-568.0 standard. All three standards now use the term 'distributor' to describe a 'connection facility', which means a patching position or reconfiguration point. This first diagram represents what the TIA refers to as the 'functional elements' of the generic cabling system. There are three layers of distributor in the hierarchical star topology. Distributor A (DA): Is an optional connection facility that is cabled between the equipment outlet and Distributor B or directly to Distributor C; Distributor B (DB): Is an optional intermediate connection facility that is cabled to Distributor C; Distributor C (DC): Is the central connection facility in the hierarchical star topology. The Equipment Outlet (EO) serves the equipment. A Consolidation Point (CP) is an optional connection facility for interconnection of cables extending from building pathways to the equipment outlet.


8: ANSI/TIA-568 Topology.

TIA568.0 defines three levels of interconnection cabling subsystem. Cabling Subsystem 1: Cabling from the Equipment Outlet to Distributor A, Distributor B, or Distributor C; Cabling Subsystem 2: Cabling between Distributor A and either Distributor B or Distributor C (if Distributor B is not implemented); Cabling Subsystem 3: Cabling between Distributor B and Distributor C. Optional 'tie' cabling may be applied. Two logical examples (shown here) are DA to DA and DB to DB. It's important to understand that the TIA 'generic cabling system' topology is flexible enough to be applied in any design scenario from a data center, a hospital campus or even a tall enterprise building. The numbers of distributors will change and some may not be optioned, but a maximum three-level distributor hierarchy and three cabling subsystems in a star topology will remain the foundation. It will help you if we visualize this particular example in terms of a campus site. Let's add three buildings in the background: Buildings 1, 2 and 3. Hopefully it makes more sense.


9: ANSI/TIA-568 Topology.

ANSI/TIA 568.1 is the commercial building premises standard. It applies the generic 568.0 model we have just covered and adds specific terminology that you are probably more familiar with. The distributors are given names, as you can see. Distributor A becomes the Horizontal Cross-connect (HC); Distributor B becomes the Intermediate Cross-connect (IC); Distributor C becomes the Main Cross-connect (MC). Cables linking them are now referred to as Horizontal or Backbone. The optional CP is still shown, but note that the EO (Equipment Outlet) is now referred to as a Telecommunications Outlet (TO) and is one of the specifically named elements within a commercial building cabling system. The standard goes on to specify the spaces these cross-connects occupy inside a building. Examples are the Equipment Room (ER) and Telecommunications Room (TR). TOs also inhabit a space defined as Work Areas (WA). There are other spaces too that we will come across in later lessons.


10: IS11801 Topology.

Now let's compare the ISO/IEC wiring standard IS11801 to the TIA568.1 topology. The ISO standard represents the same thing in a different style using alternative terminology and this can be confusing to the market. There are also minor differences in requirements to be considered between the standards when comparing different vendor's products. ISO terms of use also include TO's and CP's, but in addition there are Floor Distributors (FD), Building Distributors (BD) and Campus Distributors (CD). This is a good example of how these standards relate to each other, or not!


Question answer: [x]

13: Component, Link & Channel Specification.

Another very important topic that the wiring standards include is component, link and channel specifications. It is important that the mechanical properties and transmission categories of components used in the same cabling system be properly matched. This ensures a consistently high level of dependability and transmission performance. To achieve this the wiring standards define a series of specifications for components such as connectors, cables, overall link and channel performance. It should be noted that both the TIA and ISO use the designation of category when describing cable, cord, and hardware but the TIA also refers to categories when describing 'groups of components such as links and channels' while ISO refers to those as a 'class'. The maximum channel distance for horizontal copper cabling is defined as 100m, and the total length of equipment and patch cords plus work area cables should not exceed 10m in any one channel, with a horizontal link cable of 90m. There is also a recommended minimum distance of 15m between the patch field and consolidation point if present in the channel.


14: TIA/ISO Copper Specification.

This graphic represents the evolution of building wiring standards specification for the copper cabling channel. We need to be a little careful about putting dates alongside these standards as we have seen interim addendums are added in between standards and therefore completion and publication dates can vary by months. Sometimes component specifications are completed at different times to the channel specification. In addition, application interfaces are specified by different standards bodies such as IEEE and arrive at a different date again. Let's just run through the copper TIA categories and ISO/CENELEC classes without making it a history lesson, as these are of paramount importance to the cabling designer in our market. Category 3 (Class C) is specified to 16MHz and since the 2000/2002 revisions of TIA/ISO standards is not recommended for use in the horizontal. It is though still used for voice or sometimes Building Automation System (BAS) backbones often in multipair versions of typically 50 or 100 pair. Category 4 and Category 5 (Class D) can now be considered obsolete. Category 5E (Class D 2002) is specified up to 100MHz and is optimized for 4-pair transmission models whereas the now obsolete Category 5 cable was only designed to use two of the four pairs.


15: TIA/ISO Copper Specification.

Category 6/Class E is specified to 250MHz and offers over twice the bandwidth of Category 5E, providing a more stable platform for applications by offering lower error rates for traffic such as VoIP and video. The Augmented version of Category 6 (Category 6A /Class EA) has had component and channel specifications since 2004 and is specified up to 500MHz. Key advantages are: Applications have been developed specifically for Category 6A, with the IEEE802.3 10GBASE-T as one example. Category 6A uses the standard modular jack (RJ45) and offers full backwards compatibility with existing systems. Category 6A is supported by both TIA and ISO standards. Category 7 (Class F) is specified up to 600MHz and is endorsed by ISO, but not TIA. It is based upon S/FTP (shielded) cable with a connector that is different from that of the modular jack (RJ45) to achieve channel compliance. Category 7A (Class FA), is specified to 1000 MHz, requires an S/FTP cable (with individually shielded pairs) and a non-RJ45 style modular jack. To date, there are no applications that require the use of Category 7 or 7A and neither are recognised in TIA-568. Category 8 is a cabling specification to support 40Gbps. This cabling is specified to 2000MHz, so beyond both Category 6A and 7A, but limited to a 30m channel.


16: TIA/ISO Fiber Specification Single-mode.

Let's now take a look at fiber optic cabling standards. The table shown here is from IS11801 and defines the current 'categories', formerly 'types' of Optical Single-mode (OS). OS2 is fiber cable with a Zero Water Peak to the ITU-T (International Telecommunications Union-Telecommunications) G.652C or D standard. OS1a has now replaced OS1 which was not Zero Water Peak, so unable to support the wave division multiplexing that offers higher speeds on fewer cores. OS1a is designed for use indoors with tight buffer support and OS2 which has been available for a number of years is ideal for outdoor use and longer distances still due to its lower attenuation specification.


17: TIA/ISO Fiber Specification Multimode.

This graphic shows the multimode fiber categories. It demonstrates the typical distance to application speed support envisaged within the standards. OM1 and OM2 fibers, like OS1, are now being 'aged' within ISO/TIA standards. This table shows the minimum performance for each of the OM glasses. Overfilled launch defines a light source and Na (Numerical aperture) that results in all of the fiber modes being exposed to the source - typical with LED optoelectronics. Effective Modal Bandwidth (EMB) is dependent on the differential mode delay of a fiber, or DMD, which is the primary bandwidth limiting factor of multimode fiber. This is expressed as megahertz Kilometer. You will note from the table that OM3 and OM4 multimode fiber is laser optimized for transmission at 850nm, they have become the dominant multimode fiber types supporting the lowest-cost interfaces at 1 Gigabit and 10 Gigabit speeds and beyond, over good distances for local area type networks. OM5 is the standard for the Wide Band Multimode Fiber (WBMMF) and has an additional low loss window specified at 953nm allowing it to take advantage of relatively low cost wave division multiplexing (WDM).


Question answer: [x]

20: Which Design Standard?

In addition to the main cabling standards discussed, we need to make some sense of the other associated wiring standards available, by understanding which ones YOU as a designer may have to apply. Then you will be able to select the appropriate design standard, first by applicable region, ANSI/ISO/CENELEC, then by topic area, for example Cable Pathways and Equipment Room design or Intelligent Building Infrastructure design. Let's look at the standards from the regional areas we have just reviewed and in terms of the design topic areas you are very likely to be involved in.


21: Associated Wiring Standards.

There are three associated wiring standards topics that we need to apply in any commercial building wiring project and are not detailed fully or specifically in TIA-568, IS11801 or EN50173. These are: Installation, Administration and Grounding and Bonding. Let's start with the topic area we can refer to maybe as installation design i.e. the more practical aspects of designing a wiring system. TIA-569 is a standard that comprehensively specifies installation planning for cable pathways and spaces. Pathways being cable containment, ie trunking, conduit, trays and voids that are installed before the actual wiring takes place. Spaces may refer to Equipment Rooms and Telecommunications Room design and layouts.
The ISO 14763-2 is the International equivalent. The European EN50174 divides general installation topics into two parts: Part 2 is internal installation including some grounding and bonding and Part 3 is external installation. It should also be noted that some installation practices are also covered in the general cabling standards we covered earlier.
Next up is administration standards which cover labeling and color coding of the infrastructure, which can get very detailed especially with intricate multicore fiber designs we will come across later. So they detail how the infrastructure should be identified to aid accurate administration which would include patching for example. The TIA-606 has for example included more recently a data center cabling addendum. Internationally, admin is covered in 14763-1 and CENELEC 50174 part 1.
The third general topic group is that of grounding and bonding standards which is covered by TIA-607 in North America. This topic area is important in terms of the IT infrastructure and applications operating effectively within or between buildings. Often grounding and bonding is the discipline of the electrical contractor but cabinets, frames and containment systems need grounding and bonding, and it's integral to the performance of an FTP/STP cable system or armored cables. Grounding and bonding can be a regulation as opposed to a recommendation in many instances.
Note: that the International standard, new in 2015, is ISO/IEC30129 and this was based on the CENELEC 50310 application of equipotential bonding and earthing in buildings with information technology equipment, and TIA-607.


22: Associated Wiring Standards.

We also mentioned in this webcast that there are associated design standards targeting specific wiring environments, two common examples would be the data center and building automation, the latter sometimes referred to as intelligent or smart building wiring. The TIA and ISO/IEC also have standard specifications for wireless connectivity (cabling of access points) and the IEEE has a standard for Power over Ethernet. These are not summarized within the cabling standards as 'associated' but are useful in the design, planning and installation of any cable infrastructure.


23: Associated Wiring Standards - Wireless.

In the wireless world, in order to support the high speeds and high densities anticipated for wireless, the cabling industry has been at work updating wireless standards. TIA TSB-162 Telecommunications Cabling Guidelines for Wireless Access Points (WAP) and ISO/IEC 24704 Information Technology - Customer premises cabling for wireless access points, provides guidelines for connecting WAPs to the local area network in the building. The approach suggested in these documents is to pre-cable the building before the access point equipment is installed so that the building is wireless ready and there is minimal disruption when the access point equipment is installed and commissioned. The TIA has introduced another standard in order to address appropriate AP density. ANSI/TIA-4966 is specifically designed to cover educational facilities, but the recommendations are useful for any large indoor areas or buildings with high concentrations of wireless clients. These guidelines identify variations in wireless coverage based on their usage.


24: Associated Wiring Standards - Power Over Ethernet.

Power over Ethernet (PoE) has gone mainstream in recent years with the publication of IEEE802.3af and 802.3at, and the most recent 802.3bt standards. By providing data transmission and power simultaneously over the same industry standard cabling, PoE has enabled a new breed of devices to be delivered to the market. Devices such as Wi-Fi access points, IP phones and security cameras utilize PoE as the primary means of power - external power supplies are no longer needed. This technology has in turn been a true enabler for the market success of these devices. The breadth of existing devices utilizing PoE has driven suppliers to demand more from the underlying infrastructure so other PoE devices can be created. The new infrastructure must deliver more power while increasing efficiency. With some devices exceeding gigabit Ethernet limits, the standards will also need to adapt to allow for PoE on higher bandwidth links, such as 10GBASE-T.


Question answer: [x] [x]

27: That Completes This Lesson.

Welcome to Key Standards - Applications. This lesson will cover the relationships between the standards and the applications used on these channels.


2: Applications Role In Cabling Design?

So why is it important to know about applications in order to design cable systems, and what defines applications in this context? Applications in the context of building wiring design are the OSI Layer 1 physical interfaces and Layer 2 data link layer protocols that will directly run over a cable design. These are covered by the standards and many are developed by IEEE, such as the various versions of Ethernet but another application example is 'Fibre Channel' that is used particularly in data center design. You don't need to be an expert on these layers necessarily but enough to understand the limitations and impact they will have on your cabling design or of course vice versa! The short answer to why is it important to know about applications, is that they are intrinsically linked to cabling design. A decision has to be made on the media used i.e. copper, fiber or wireless and then the specifications of that media. This will include the interfaces used on the media to couple to application equipment, the current and future capacity of cabling required for the applications, the flexibility required in reconfiguration, the performance of the application and the future application aspirations. The applications planned now and in the future may even dictate the installation process and the final testing of the cable system, or the way the results are verified.


3: Applications Role In Cabling Design?

Probably the most important aspect needed to be understood about applications is the media options available, the distance it can be supported before performance starts to be impacted and also which interfaces it requires. It is also important to understand right from the offset that the applications standards committees such as IEEE802.3 Ethernet will offer more than one style of Layer 1 interface for a given speed of application. So for example 10Gbps Ethernet may run on multimode or single-mode fiber and certain copper categories of media. Apart from the media differences there will be several variances including the physical interfaces (connectors), the number of fiber cores or pairs required, the frequency and wavelengths used and the distances supported. So you can see how cabling design and applications are intrinsically linked.


4: Copper Applications - Next Generation.

It is important that the designer understands trends and new developments to make informed choices. We discussed earlier that the development of Category 8 copper specification and this coincided with the IEEE802.3bq study group work on NGBASE-T transceiver (NG meaning Next Generation). The goal was to offer backward compatibility to existing legacy cabling and applications using the RJ45 equipment outlet interface connector, but as application speeds continue to rise, a consequence is that the supported distances become shorter. With this in mind, IEEE 802.3bq supports 40Gbps over a 30 meters cabling channel using Category 8 cabling, so this copper interface is likely to be restricted mostly to data center applications designs. However as we will see it can more easily be achieved using fiber over more useable drive distances.


5: Fiber Application Standards 40GbE & 100GbE.

The main media proposed for 40G and 100G is fiber and the IEEE802.3ba study group are working on it. Both single-mode and multimode fiber systems are supported but limited to different distances using various optical PMD interfaces. All of the optical PMDs developed share the common architecture and naming convention of SR (short range), LR (long reach) or ER (extended reach). The 40GBASE-SR4 and 100GBASE-SR10 PMDs are based on 850nm wavelength and support transmission maybe to 100m on OM3 fiber and potentially 150m possible using OM4 fiber with Multi-Fiber Push On (MPO) connectors. The MPO-12 shown here on the SR4 PMD has 12 terminated fibers, 4 lanes (fibers) of each are used in either direction. The effective data rate per lane (fiber) is 10Gbps. Therefore, the 40GBASE-SR4 PMD supports transmission of 40Gbps Ethernet over a path consisting of 4 parallel OM3 fibers in each direction, while the 100GBASE-SR10 PMD will support 100 Gigabit Ethernet over a path consisting of 10 parallel OM3 fibers in each direction using an MPO-24 connector.


6: WBMMF SR PMD Alternative.

The potential for OM5 WBMMF fiber, that we saw mentioned in the previous webcast, now becomes apparent. Instead of using large numbers of parallel fibers to multiplex, four colors of light are multiplexed instead. This graphic shows a comparison of the previous SR4 PMD's versus the prospective of using WBMMF PMD's. The 40G SR PMD uses four 10 Gigabit signals in parallel, depicted by the four blue stripes, each one representing a separate fiber. One set for the transmitter and one set for the receiver, requiring a minimum of eight fibers. In contrast, 40G using SWDM can be condensed down to transmission on a single fiber in each direction, each carrying four wavelengths instead of one, so a total of two fibers used. For 100G, SR10 uses 10 parallel lanes (20 fibers) each using 10Gbps, but if using SWDM this could be collapsed further to a single fiber pair by transmitting 25Gbps signals on each wavelength. This is a demonstration of the continual advances being made in fiber PMD technology.


7: Backbone Distance - Fiber.

Standards still define the maximum enterprise design distance of a fiber backbone as 2000m. As with copper, application interface drive distances may limit this distance depending upon the type of fiber used and of course the number of connections in any channel design. There is much to consider when planning fiber backbones so let's start by reviewing the standards based fiber types now defined as categories. This graphic simply demonstrates the relationship between categories of multimode fiber and drive distance of certain application interfaces. Optical Multimode OM1, and OM2 have now been aged and are not recommended as they are not laser optimized and as such cannot support the higher speed interfaces often required today in the horizontal or backbone. OM3 and OM4 are LOMMF fibers so optimized for low cost high speed lasers, increasing the available bandwidth. OM5 offers a future for even higher speed applications to take advantage of its additional wavelength specification, being able to support wave division multiplexing in the 850nm to 953nm range.

The attenuation of each of these categories is also defined in the standards and we can see here OM5 being slightly lower attenuation at at 850nm.

Looking at supporting longer backbones and or higher speeds still the use of single-mode OS1a has now replaced OS1 which was not Zero Water Peak, so unable to support the wave division multiplexing that offers higher speeds on fewer cores.

OS1a is designed for use indoors with tight buffer support and OS2 which has been available for a number of years is ideal for outdoor use and longer distances still due to its lower attenuation specification.



8: IEEE Optical Applications up to 400G.

As adoption of 10G is declining, the IEEE has been hard at work in the development of optical applications beyond 10G spanning from 25 to 400 Gbps. To support the market requirements for relatively low cost transceiver technologies, a number of options have been developed or are in process of development for multimode fiber, up to 400 Gbps to support at least 100m over OM4 fiber. The SR suffix is used to denominate "Short Range" for multimode applications. Single-mode options up to 400 Gbps have also been defined, with some of the newer alternatives reducing the distance support to 500m in order to cover the requirements of hyperscale data centers, while reducing the cost of single-mode transceivers. The single-mode suffixes include LR for "Long Reach" 10km specifications, ER for "Extended Reach" 40km specifications, and the more recently introduced FR that stands for "Fiber Reach" (2km) and DR for Data Center Reach (500m). Duplex options highlighted here in green are generally preferred by customers in order to minimize the fiber cabling requirements, and duplex options have been defined for both multimode and single-mode. Parallel options, highlighted in brown here using more than two fibers have also been defined for multimode and single-mode. This is in order to increase data rates by using multiple pairs simultaneously. The SR4 suffix is used to denominate the use of 4 fiber pairs in multimode applications. For single-mode, although the numeric suffix was originally used to designate the number of wavelengths for multi-wavelength applications, the numeric suffix is now starting to be used to designate the number of pairs, such as DR4, designating 4 pairs for 500 m data center reach. Wave Division Multiplexing, highlighted in grey, has been defined for single-mode variants for some time already, such as 10 km Long Reach four wavelength LR4, and has most recently been defined for multimode with a two wavelength objective for 400 Gbps. Additional optical applications have become available in the market, including options to achieve extended reach over installed multimode fiber for 25, 40 and 100G. Additionally, the Fiber Channel (FC) specifications continue to evolve towards 128 Gbps on multimode and single-mode. Wave division multiplexing technologies enable the support of 40 and 100 Gbps Ethernet applications over duplex fiber, and extended versions of serial and WDM applications are available to deploy over the installed base of multimode. Parallel and WDM options are also available for single-mode.


Question answer: [x]

11: Standards Summary.

In some respects we appreciate standards is a painful topic to study, but some like bonding, fire and smoke will have serious risk implications if not applied, although many are recommendations only. As we mentioned at the offset, even those that are recommendations will likely be specified as contractually binding and have legal implications if you fall outside of them.


12: That Completes This Lesson.

Welcome to Horizontal Designs - Standards. In this section, we will deal with the standards-based enterprise horizontal channel design. Design standards provide minimum requirements for specification. The key standards covering horizontal design are covered in ANSI/TIA-568 for North American, ISO/IEC11801 (International) and CENELEC EN50173 for Europe.

2: Horizontal Channel.

Let's ensure we have an understanding of the basics first, as this section will only show the upper schematic-style graphics, although we can see here how the design relates to the components as shown below them. The example shows the maximum recommended channel connector count of 4. So, the first thing to notice is that the connector at the equipment at either end is not included in this number. There is insertion loss at the end connectors but it's taken into account within the network interface design. 'C' in the graphic indicates a mated connector, typically a plug to jack that many would know as RJ45. Other connector type options are possible though as we will see.
Remember the horizontal channel can also be fiber based but this is still fairly rare in commercial office space other than in data center environments. Looking along the top graphic, from the left, we can see the equipment cable shown as half pink and half blue, which infers this can be cord (stranded - flexible multi-wire) or cable (solid conductor). It is worth considering here for a moment the pro's and con's of each type.
Stranded conductor is more flexible and places less strain on its terminated connector interface when handled. Solid conductor generally exerts lower attenuation, so it is good for longer runs. As we will see, standards recommend a maximum of 10 meters of stranded in the channel design, otherwise any attenuation deficiency will need to be taken into account for the overall channel length. We can also see the that the equipment end of this cable has a modular plug. But, the other end is terminated to the rear of the purple panel (1) and directly punched down.

3: Horizontal Channel.

The cord between panels 1 and 2 is a double-ended patch cord (usually stranded). In most cases, this cord will be terminated at each end in a modular plug. However, depending on the type of administration hardware (patch panels) being used, the plugs may be proprietary, for example 110-type or some other style. So, note that the standards only specifically specify the modular plug/jack style for copper at the Telecommunications Outlet (TO). It's also the connector of choice on most active hardware at either end.
Alternative connector styles still need to comply with standards-based performance specifications. Alternatively, in the case of low performance connections, for example traditional voice or BAS applications, administration patching may even be completed using jumper wire, but this is becoming rarer as application performance increases.
The horizontal cable indicates a solid-conductor cable. It is terminated directly to the 'blue' distribution field panel (2) and to the CP to the right (3). In this diagram, this is the Consolidation Point (CP) position. Moving further to the right, we can see a CP cable, again shown in pink/blue, meaning it can be solid or stranded. But, as we will see, some standards require solid-conductor cable for this.
Finally, the cord to the right connects the TO to the terminal equipment. Again, this is usually a stranded-conductor cord, with a modular plug on each end. You can now picture what we are looking at when we see these channel diagrams in the graphics.

4: Cordage Reductions.

ISO, CENELEC and TIA have design models for the horizontal copper channel, with the CENELEC and ISO models being virtually identical. So, for the rest of this lesson where it says ISO, also read CENELEC. There are minor differences between the TIA and ISO channel design.

Both ISO and TIA recommend the following: The maximum length of the channel shall not exceed 100 m; The maximum length of cords or jumpers should not individually exceed 5 m (the TIA specify a maximum of 5m work area cord); 'H' (the 'fixed' horizontal - Permanent Link) must be no more than 90 m, but may need to be less depending upon the cabling reduction required for excess cordage. TIA further infers that the maximum combined length of all work area cords, patch cords, and equipment cables should not exceed 27m whereas ISO does not have this limit.

5: Cordage Reductions.

It is important to understand that solid-conductor pairs are used in the majority of horizontal cables. As mentioned previously, these have lower attenuation than stranded cable, which is typically used in patch cords. How much is this attenuation? It depends on the vendor and the construction of the cable but typically, the attenuation of a stranded UTP cable is no greater than 120 percent of that of a solid cable. Shielding a cable will often increase its attenuation, so both ISO and TIA allow a stranded shielded cable to have up to 150 percent to that of a solid-conductor shielded cable.
TIA refers to this as the cord dB/100m versus solid cable dB/100m ratio, which is usually expressed as a percentage and is called the 'de-rating' value. The original standards model allows for 10m of stranded cordage in a 100m channel, but if your design exceeds that 10m, then your link channel lengths will have to be reduced. In today's modern designs where cable managed furniture and partitions, raised floors and large equipment rooms can allow for potentially long runs of flexible cord, it is easy for the total length of stranded cord to exceed 10m.

6: Cordage Reduction Calculations - TIA.

This diagram is exactly the same as the last but an interconnect direct to the TO, so an example of a simple two connector channel. ISO and TIA calculate cordage reduction in different ways, but the concept is the same. They both start by turning the channel into an all-solid-conductor cable length, as it saves the designer from working in dB's.
Let's tackle the TIA cordage reduction formula first, as its slightly less complex than that of ISO. In the following calculations we will work in meters. It starts not at 100m, but at 102m. The 102m is a combination of the 10m of cord accounted for at a worst case of 120 percent attenuation, so its equivalent to 12m of solid cable plus the 90m solid link cable = 102m equivalent all-solid-conductor channel. The TIA formula is written as C = (102 - H) ÷ (1 + D) where C = the cordage, H = the solid link length and D = the de-rating factor (percentage). D = 0.2 (20 percent), therefore 1 + D = 1.2. Note that we are using a 20 percent de-rating factor, but this varies per vendor. 20 percent, however, is fairly common for UTP cables.

7: Cordage Reduction Calculations - TIA.

So, let's look at the example in the graphic. Unfortunately, the formula is set up to calculate the cordage C. So, for our example where we need to calculate H, we have to re-organize the formula using a bit of simple algebra to: H = 102 - C (1 + D) where D is the de-rating factor of 0.2 (20 percent more attenuation). TIA allows 20 percent for 24 AWG UTP or ScTP (F-UTP), but up to 50 percent for 26AWG (finer gauge) ScTP cables, which is a de-rating value of D = 0.5. Using the example shown here, H = 102 - 35(1.2) which gives us a solid permanent link maximum of 60m. Therefore, the maximum channel will be 60m plus the actual cord length, for a total of 95m. Note in this TIA formula it assumes that all four standards-based insertion loss connections can exist inside this channel.

If all the stranded cords in the three positions indicated add up to 40m, what length is the Permanent Link (blue field to TO) allowed to be?

Answer: 54m

10: Cordage Reduction - Practice.

Even if math is not your strong point you do need to understand how this calculation works. Remember we said earlier that if you add the solid cable maximum length of 90m to the stranded cable length (the equivalent length, as if it were a solid cable) that is 10m, plus 20 percent, that makes the total length 102m. Now any stranded we use in the link, we must add the 20 percent to it, then take that away from the total length of equivalent solid cable (102m). Your answer would have been calculated as 40m plus 20 percent = 48m. The sum now looks like this: 102m - 48m = 54m. This also means the length of the channel is now 94m not 100m. You must always take this calculation for stranded cord performing worse than solid cable into account.

11: Cordage Reduction Calculations -ISO.

This diagram is exactly the same as the last, an interconnect direct to the TO. Now, let's tackle the ISO version that is slightly more complex. In all honesty, there is not much of a difference, so after explaining this once, we suggest you use the TIA calculation. ISO's suggested calculation accounts for both excessive cordage and the number of connections used in the channel. It starts not at 100m but at 107m. How you get to the 107m is a long story, but in summary it is a combination of the 10m of cord accounted for at a worst case of 50 percent attenuation, so it's equivalent to 15 m of solid cable plus the 90 m solid link cable, plus a minimum of two connectors (as shown in the graphic above) and that makes the 107 m. So, with 107 m as a starting point, and calculating the two connector interconnect model above, we would use the formula H (Horizontal cable) = 107m - 3m - FX. The 3m accounts for an allocated margin to accommodate the 2 connectors in the channel at the blue field and the TO (each equivalent to approximately 1m of solid cable) and 1m for deviation (think of deviation as a safety meter). F = the combined lengths of all of the stranded cordage (remember TIA used C for this in their formula) and X = the ratio of stranded cable insertion loss versus solid cable insertion loss which in the case of many U-UTP cables is 1.2.

12: Cordage Reduction Calculations -ISO.

Okay, let's try a calculation. If the equipment cord and work area cord total 35 m, the formula will be H = 107 - 3m - (35m x 1.2), therefore 62m. That's the permanent link in this model. So to calculate the channel, add the actual length of the cord to the link (62m + 35m = 97m). You will note this is different by 2m to the TIA calculation, partly because of the allowance for two connectors rather than four, but also because the 107m came from a worst case ratio for stranded versus solid of 1.5. You will get a chance to practice this later, so make sure you have your calculator at hand if you don't already. Now, let's take a look in detail at the design options within the Telecommunications Room and the Floor Distributor, or as TIA calls it - the Horizontal Cross-connect.

13: Horizontal Interconnect.

Within the Telecommunications Room or Equipment Room that will be serving the horizontal, we now need to consider the connection from the active equipment to the horizontal distributor, the FD (HC). This connection is made in one of two ways: Interconnect or Cross-connect. These are two terms that are of fundamental importance in design so you must be certain that you understand each and the difference between them. It is also worth introducing at this point the concept that there is a standard color code scheme recommended when labeling administration fields. We will go into this in more detail in a later lesson. The color coding scheme for administration systems has been used since the earliest days of copper cabling and has now been adopted across all three main standards bodies: TIA, ISO, and CENELEC.

The two patch fields we will now relate this to are the blue field which is used for horizontal distribution and the purple field which is used when active equipment is connected at a cross-connect panel. The use of the term 'field' just describes a group of panels. Panels may be positioned in racks, frames, cabinets or may even be wall mounted. The interconnection architecture is an alternative solution allowed when the equipment is located in the telecommunications room with the distribution (blue field). In this design, patch cords are installed between typically LAN equipment ports and the horizontal cabling. The purple fields are eliminated, therefore this architecture requires less space than a cross-connect architecture. Administration can be more difficult and less flexible when larger amounts of equipment are present, so it only suits smaller telecommunications rooms.

14: Horizontal Cross-connect.

The cross-connect architecture is a design where equipment is terminated on a separate termination field, color coded purple. The equipment ports are connected to the horizontal cabling using patch cords between the purple and blue field panels. Cross-connect design offers the following advantages. The active equipment does not need to be sited in or adjacent to the administration area, therefore it can be as shown here, positioned in an environmentally conditioned cabinet or in a separate room. The active equipment can be made secure, caged or locked off allowing cross-connects to provide the ability to separate active equipment from administration areas. This will also help reduce accidental network outages caused by administration staff activity. Active equipment does not typically have any cable management hardware, so is not as neatly and easily managed as panels. Active panel ports are expensive and will wear with constant use of patch cords.

15: Standards - Cross-Connect.

So far, we have only looked at a simple horizontal model with two connectors in the channel, the interconnect and the TO. We will now look at a cross-connect model, which is very popular in any sizeable ER or TR. You can see that a cross-connect administration position has been added to the previous example. This adds a third connection to the channel. You will note that the equipment cable here, can be either a solid or stranded conductor type. This cable could be of considerable length, especially if you have an equipment room or data center scenario where the active equipment is in separate environmental or security space. In this instance, we know that stranded-conductor cord is higher attenuation and will need reduction so it makes sense to use a solid conductor cable in this case.

The pros and cons of solid versus stranded, other than attenuation, is that the solid conductor cord should only be used for 'low-MAC' (Moves Adds and Changes) administration use. The equipment cable area is low-MAC. BAS, data, or voice equipment will be attached to the equipment panel in a fairly permanent manner, and will typically only be re-patched when equipment is replaced or upgraded. So, it is a fairly stable administration area, which is ideal for the use of solid-conductor cords, which have lower attenuation, and usually lower cost, than stranded cords. TIA would use the same reduction formula for this model, as it always assumes up to four connections within the channel, while ISO modifies the formula to allow for this additional connector by reducing the 107m to 106m. The additional purple field mated connection accounts for 1m of solid conductor cable in terms of insertion loss. The adapted formula is shown in the graphic.

16: Horizontal Topology - Home Run.

There are two horizontal distribution topologies, referred to as Home Run and Zone. The choice between the methods is based on the building characteristics and customer needs. As you will see, Home Run is a simple cost-effective way of distributing horizontal cabling. Zone wiring offers additional flexibility in design, especially useful in pre-cabled multi-tenant environments, false floor or where ceiling-fed power poles are used, allowing floor boxes and poles to be moved or removed easily.

The graphic shows that with the home run method, cables are routed directly from the serving telecommunications room's FD (HC) to the TO's at the work areas. This method is economical and direct and accounts for the majority of horizontal topology designs to date. This graphic is showing four outlets in each work area.
Note: Recall these standards-based notations: Telecommunications Room (TR), Telecommunications Outlet (TO), and the patch field in the TR. ISO calls it the Floor Distributor (FD), while TIA refers to it as the Horizontal Cross-connect (HC).

17: Horizontal Topology - Zone Cabling & CP.

Zone cabling is an approved alternative to Home Run cabling. This method is called Zone Wiring or Open Office cabling. It is referenced in the IS11801 standard and is also covered within the TIA/EIA-568 standard. Zone cabling is a useful option for supporting open office work areas. Open office design is now an established practice based on modular furniture, flexible partitions and project workgroups. Similarly, zone cabling is very suitable and recommended for above-ceiling horizontal design. Although this seems to be a more complex channel design and introduces more components and potentially cost into the channel, this can be untrue.

Zone wiring allows for more flexibility in final TO and equipment positioning, which suits many projects and may reduce costs in the short term. The CP to TO 'extension' can be added at a later stage and removed when not needed. Equipment may even be fed directly from the CP, although as we will see later this then has a different name.

18: Horizontal Topology - Zone Cabling & CP.

Zone cabling divides horizontal cabling into two parts. First, a permanent section from the telecommunications room FD (HC) to the consolidation point (CP). ISO calls this the CP link. Secondly, a flexible section of cabling run from the CP to the TO's (extension cables). This may be installed in flexible conduit or left individually run. ISO and CENELEC allow for flexible cord (stranded copper) to be used between the CP and TO, but TIA-568 recommends solid cable be used here. The consolidation point establishes a cluster or group of work areas (zone). These work groups can contain maybe 6 to 12 Work Areas although TIA-568 and ISO recommend a maximum of 12 WA's served from a single CP. Determining the serving area of the CP will help the designer lay out the CP locations on the floor plan. Columns, or pathways near a column, are a natural mounting location for access ceiling CPs since they provide a hidden place to transition the cabling from the ceiling to the work area space. Access floors provide the best method for placing CPs since cables can easily be hidden to virtually any location.
Consolidation points must house and otherwise protect the interconnection of the zone and extension cables. The Zone method requires the use of at least Category 5E cabling. At least one vendor makes a 25-pair Category 5E cable. This has some advantages in terms of installation speed and containment space. Alternatively, if you need a higher category, you can pull multiple 4-pair cables to the CP. Some vendors make pre-terminated connectors to modular jack assemblies that can be used between the CP and TO. Alternatively, you can build your own solid or flexible assemblies, using single-ended cords or double-ended cords cut in two.

19: Horizontal Topology - Zone Cabling & CP.

This graphic is showing another 3-connector channel design, although now it's an interconnect (no purple field to the left) but we have introduced a CP (Consolidation Point). You will note that the CP cable here can be either a solid or stranded conductor type. TIA requires this cable to be solid conductor, but ISO allows it to be a stranded conductor cable. It's a best working practice to use solid-conductor cable, provided the MAC rate is low, which typically it will be as individual floor boxes will rarely be removed from the CP. The standards define the zone cable as 4-pair, Category 5E minimum. The CP cable could be of considerable distance, especially if you have a raised floor environment scenario where the TO is in a floor box.
The TIA reduction formula for calculation remains the same. The ISO formula, as in the previous graphic allows for this additional connector reducing the count from 107m to 106m. In addition, the formula adds an allowance for two different reductions (FX and CY) in case two different cord types are used. One is for the CP to TO and one is for the patch cordage. In reality, it is definitely a best working practice to ensure only cables from a single vendor are allowed in the channel, so we can ignore this if using the ISO formula. You should also notice that a minimum 15m rule has been applied between the blue field and CP. This was introduced into the TIA and ISO standards after the introduction of the 1000BASE-T application, in their 2001 and 2002 revisions. You need to be careful in the application of this rule, as it will also apply in a data center design where you may be cabling cross-connect to cross-connect within the computer room.
Remember, TIA and ISO allow up to twelve Work Areas to be supported from a single CP. Standards do not allow the CP to offer a cross-connect. It has to be an interconnect, as a cross-connect would take the connector count to potentially five. In other words, as an example, a modular plug is connected into a jack at the CP, so the TO cannot be also terminated at the CP and then patched. There is an exception for this in BAS design, where a cross-connected HCP (Horizontal Connection Point) can be created to serve a BAS coverage area. This is a specialized design topic that is addressed in the SP7700 Cabling for Intelligent Buildings course.

20: Standards Cross: Cross-connect & CP.

We can see here the full four connector horizontal design envisioned by the standards. Let's use this graphic to stop and take stock of what we have learned so far in this part of the lesson. We know it makes sense to use solid conductor cables for the equipment cable and CP cable. In fact TIA requires it. We also know that we need to allow for the additional attenuation of stranded cordage, but ONLY if the total cordage in the design exceeds 10m. TIA uses one formula and ISO/CENELEC uses another, but there is not much difference between them. We have learned that there are not only maximum distances, but also a 15m minimum distance between the blue field and the CP.
Incidentally, it is worth pondering at this point: are all these distances the physical length of the cable or the electrical length of the cable (tested pair length)? Before we answer that, you may ask, are they not the same? The answer to that is 'No', because the electrical (and tested) length will be looking at the length of the pair, not the length of the cable jacket. Obviously the length of the twisted pair will be longer than that of the cable jacket. The answer to the original question is that cable jacket length should be used. This may seem a bit odd, but as different cables, vendor designs, and pairs will vary enormously, not to mention testers, the physical length is always going to be on the safe side.

21: Standards MUTOA.

A MUTOA is a Multi-User Telecommunications Outlet Assembly and is defined in all of the standards. Why define the term MUTOA then? Why is it not just a group of TO's? The reason for that is that designs in modern buildings often have to cope with open plan offices and desk arrangements that are away from fixed building positions - often as a pier or a wall, as in the graphics. So far, we have said that a Work Area cable length is restricted to 5m, but with modern cable-managed furniture or partitions, this can be safely extended. This extended cable will be a stranded cord, as it's a high-MAC area, therefore channel reduction must take place.

22: Standards MUTOA.

So, let's be clear on the differences between this and a CP. A CP, by standards definition, does NOT attach directly to terminal equipment, it connects to a TO. A MUTOA is a multiple TO and connects directly to the terminal equipment but cannot be connected to the FD via a CP. A CP, by standards definition, can be below a floor or above a ceiling (providing plenum rules are applied, if required). So, it may be considered a 'technician' patching position. A MUTOA, like a TO, is a user-patchable position, so it should be 'visible' and easy for the end user to access. As far as standards are concerned both the CP and MUTOA should be fixed in position to the building structure.
In some cable-managed furniture you can install a TO, so if we placed a TO here, what would that make the MUTOA position? That's right, it would turn the MUTOA, by definition, into a visible, user patchable Consolidation Point (CP).

23: That Completes This Lesson.

Welcome to Horizontal Designs - SYSTIMAX.

2: SYSTIMAX PowerSUM v Standards.

In most RFQ responses, you will be required to comply with standards, but remember they are only recommendations (although the RFQ may make them a binding obligation to comply) and standards are minimum-based. The following additional flexibility in SYSTIMAX design in the next graphic may require approval from the customer or consultant, but they are supported under the SYSTIMAX warranty. If we compare the SYSTIMAX PowerSUM guidelines to those of the standards, we will notice the following differences. In zone wiring designs, SYSTIMAX also allows the use of its x061-25F, fully Category 5E-compliant 25-pair cable which is application warranted for up to, and including, 1000BASE-T, over the full 100 m channel. CP positions can be moveable, as long as it does not require re-termination when doing so. SYSTIMAX allows for up to 18 WA's to be supported from a single CP whereas TIA and ISO allow 12. This limitation is really to do with it being an 'interconnection' position, which means that unconnected TO plugs will become unmanageable at the CP area. The CP cable connection, at the CP, can be terminated with a plug to jack, OR as a 'transition' connection, whereby an open ended cord may be punched directly to a VisiPatch 360 panel, and still maintain Category 5E application support.

MUTOA positions can be moveable, as long as it does not require re-termination when doing so. The MUTOA can also be positioned like a CP, if required, below-floor or above-ceiling, etc., as long as the appropriate plenum ratings are observed. The MUTOA area work cables are not limited to 20m and 22m, as in ISO/TIA, as long as the appropriate stranded cord reduction calculation takes place.

3: SYSTIMAX GigaSPEED XL Design.

GigaSPEED XL produces a uniquely 'matched' channel with guaranteed headroom over Category 6 and forms part of the warranty. This performance level is referred to as the XL7 channel (x071 cable). GigaSPEED XL offers the following significant design benefits. Up to 6 connectors within the channel. This example shows two additional connections at an inter-room link, such as in a large equipment room or data center, where interconnection of cabinets is required and it also serves the local blue field horizontal distribution. The 6 connector count also allows for the potential to use a cross-connect CP position, which is very useful in, for example, multi-tenant buildings and retail point of sale environments. The 6 connections can be positioned anywhere within the channel and there is no minimum CP 15 m rule. Again, particularly useful in data center designs, where there can be multiple connections in close proximity (as shown here). XL designs still limit the maximum channel to 100 m, link to 90 m, and apply reduction for stranded cordage over 10 m. IMPORTANT: It should be noted that to maintain the guaranteed XL7 headroom above the standards, XL designs should limit the total stranded cordage in the channel to 10 m. It's good design to use solid conductor cords where changes are less frequent, ie. from CP to TO and equipment cable to panel in a cross-connect. If your channel requires greater than 10m stranded apply the channel reduction calculation and CommScope warranty the channel to Category 6 not XL performance.

4: SYSTIMAX GigaSPEED XL Design.

The scenario we have here shows the use of GigaSPEED XL and its advantage with extra connections within the channel. Here we have a training room where the customer will use up to ten PCs in the room. However, the positioning of the PCs in the room will vary, depending upon the course, so the room is locally cabled with 30 connections back to a VisiPatch 360 CP in a cabinet. The ten cables are then run from the room to the FD (HC). In reality you will want to cable some spare. The advantage of the fifth connection here is that in a traditional interconnect CP design, the 30 cables at the CP will just hang loose unmanaged. In this design, patch cords in the CP provide a tidy managed solution. Equally, this scenario could be used in multi-tenant design or retail P.O.S design and many other environments.

5: SYSTIMAX GigaSPEED XL Design.

In this scenario we can see GigaSPEED XL being used in a data center design that has a secure equipment area within an Administration area, running to a Zone distribution cross-connect. So this is an example of using all 6 connections allowed in the XL Category 6 solution to full advantage. If exceeding 10m of stranded patch cord in the design, the channel length needs to be reduced using the TIA C=(102-H) ÷ (1+2) formula.

6: Design for the Data Center GigaSPEED Xpress.

Xpress has been designed specifically to tackle data center design and installation challenges. It takes the best advantages from both XL and X10D - design freedom, space savings and no Category 6 mitigation required for alien crosstalk suppression. While traditional cable designs are recommended for only 40 percent fill ratios, the strength of this unique cable design allows users to load cable into cable management pathways at a fill ratio of up to 50 percent with full PoE and Alien Crosstalk capabilities or 9 inch (230 mm) deep without altering the performance of the cables due to crushing. The majority of conduit fill guidelines need to be based on internal diameters and recommended maximum fill of 40 percent for 3 or more cables.

7: GigaSPEED Xpress Data Center Solutions.

The main advantage of using Xpress cable over existing standard Category 6A cable is the smaller diameter. It provides 500MHz support to 60m and allows for guaranteed 10GBASE-T, in worst case 6 around 1 channel configurations, without the post-installation testing and mitigation required by Category 6 cabling schemes. There is no 15m minimum rule, up to 4 connectors may be allowed in the channel, and there are no minimum patch cord length restrictions.

8: GigaSPEED X10D Design.

Now, let's look at the design differences for GigaSPEED X10D channel design, both U/UTP and F/UTP.

9: GigaSPEED X10D Design.

The GigaSPEED X10D solution has always supported worst case installation conditions for alien crosstalk both, in the cable design and at grouped connector locations with modular and VisiPatch 360 panel designs. GigaSPEED X10D is designed to alleviate the two alien crosstalk phenomenon ANEXT and AELFEXT. If you recall, ANEXT (near end) and AELFEXT (far end) occurs between adjacent channels. Multiple signal influence into another cable will result in PSANEXT and PSAELFEXT (also known as PSAACR-F). GigaSPEED X10D meets the requirements for off-site pre-bundling and pre-termination, and/or worst-case installation conditions to 100 meters.

10: GigaSPEED X10D U/UTP & F/UTP 'Design Advantage'.

This picture shows a typical X10D installation, in this case using a modular panel. Worst case looming (combing and grooming) of cables over the FULL channel is permitted, the worst case scenario for Alien Crosstalk. X10D design rules include: Apply a maximum 4 connections in the channel design; Apply a 5m minimum cable (91B) length for 3 or 4 connector channel and a 3m length for a 2 connector channel; If exceeding 10m of patch cord in the design reduce the channel using the TIA C=(102-H) ÷ (1+2) formula. For SYSTIMAX U/UTP or F/UTP 91B cable, the de-rating is as before with PowerSUM and XL, 0.2 (20 percent) so use C=(102-H) ÷ 1.2. GigaSPEED X10D design does require some minimum cord lengths. But as we have seen, these have been reduced to just 2 meters for equipment and 1 meter for patch cords.

11: GigaSPEED X10D U/UTP & F/UTP 'Design Advantage'.

There are two ways of running cables - NR and RB. NR stands for 'No Restrictions' Combed (Groomed) and RB stands for 'Restricted from Bundling' or Randomly tied. These were used in design of the original X10D systems to ensure minimum cord lengths are maintained to obtain X10D channel performance over and above the emerging standards. This is now ONLY a design consideration if you are moving to 10G on legacy products, if so consult the appropriate design guideline. Today's GigaSPEED X10D designs using U/UTP MGS600 series information outlets and 360GS10E series cords, and for F/UTP HGS620 series information outlets and G10FP cords, there are no such restrictions, therefore all cables can be combed and groomed if required. There are however minimum distance requirements in the 10G channel and these are the same for both the X10D U/UTP and F/UTP channel designs.

12: GigaSPEED X10D U/UTP & F/UTP 'Design Advantage'.

It is important to understand that the minimum cord lengths only apply to X10D channels (10Gbps). X10D, PowerSUM, and XL cords of any lengths can be used to support Category 6 applications or lower. But planning should include for 10Gbps migration. The table shown here illustrates the Work Area Channel models. We will look at the data center models later.

13: Figure 1: Example of 2 Connection Work Area Channel.

The following illustrations of the various channels identify connections from the central equipment to the work area equipment. They show the ANSI/TIA-568 Commercial Building Telecommunications Cabling Standard and ISO/IEC IS11801 Information Technology - Generic Cabling for Customer Premises defined configurations containing up to four connections. These models are also commonly applied in backbone cabling subsystems. Configurations more like the Data Center Channel models (figures 6 - 10) would then be used. As you work through these models, it is a good idea to cross-reference them to the table we have just reviewed using the copy of the GigaSPEED X10D Design and Installation Guideline found in your download area. The most basic Channel Model has only 2 connections and is typically referred to and tested (without the cords) as a Permanent Link. The Horizontal with the cords may also be tested as a Channel. The figure number, in this case (1), refers to the X10D design guideline.

14: Figure 2: Example of 3 Connector Cross-connect Work Area.

A third connection can support two different channel models, a cross-connect or a Consolidation Point. Figure 2 above shows a cross-connect work area model. At large sites or sites with a high density of work stations or where space constraints might otherwise dictate, the Telecommunications Room can be configured with a cross-connect. The cross-connect is a solution that separates equipment administration from cabling administration, and provides maximum flexibility and protection for horizontal cabling. This configuration is tested with the cords as a channel.

15: Figure 3: Example of 3 Connector Interconnect & CP Work Area.

Where open office spaces may have a high turnover or where installation may be staged, the horizontal cable can be terminated at a Consolidation Point. This is often done for supporting modular office designs, allowing easy cabling changes from the Consolidation Point (CP) to the TO that follow changes made to the open office space. This configuration is typically called a Permanent Link. It may be tested without the cords as a Permanent Link, or with the cords as a channel.

16: Figure 4: Example of 4 Connector Cross-connect & CP Work Area.

Figure 4 is an example of a large open office site, where administration flexibility calls for four connections in the channel. This configuration offers flexibility and protection at both ends of the horizontal cabling, providing the advantages of cross-connection in the TR and the flexibility of the CP for modular office design. This configuration is typically referred to and tested (with the cords) as a channel.

17: GigaSPEED X10D.

Data center cabling is an excellent application for GigaSPEED X10D, allowing data center operations upgrades when 10GBASE-T equipment becomes available. Now let's look at the configurations for supporting the ANSI/TIA-942 Telecommunications Infrastructure Standard for data centers.

The following illustrations identify various channels between different areas within a data center's computer room. These standards defined configurations contain up to four connections. A connection is where two cabling segments come together, while the connections, as usual on the end equipment, are not counted in the models. You will actually notice, if you compare the models with those of the work area we have just reviewed, there are few differences, as in reality a switch or server replaces the work area terminal equipment, so you are running rack to rack. Let's take a look.

18: Figure 6: Example of 2 Connection Interconnect to Interconnect.

We start at Figure 6, as we are in step with the GigaSPEED X10D guideline and Figure 5 is not relevant. The most basic channel model has only two connections and is typically referred to and tested (without the cords) as a Permanent Link. The horizontal with the cords may also be tested as a channel. This could be horizontal switch-to-server or backbone core-switch-to-server-switch.

19: Figure 7: Example of 3 Connector Cross-connect to Interconnect.

A third connection can support two different channel models, a cross-connect or a CP. Figure 7 examples a large site or sites with a high density of switching equipment or where space constraints might otherwise dictate, the Horizontal Distribution Area (HDA) can be configured with a cross-connect. This configuration is typically referred to and tested (with the cords) as a channel. This configuration can also be applied to backbone cabling with a Main Cross-connect (MC).

20: Figure 8: Example of 3 Connector Interconnect with a CP.

Figure 8 may be used where a site administrator may need flexibility or where the installation is staged. The horizontal cable can be terminated at a CP. It might be used for example to terminate a horizontal bundle at the middle of a row of equipment, and allow the site administrator to apportion horizontal cables between sections of the row as needed. This configuration is typically called a Permanent Link. It may be tested without the cords as a Permanent Link, or with the cords as a channel.

21: Figure 9: Example of 4 Connector Cross-connect to CP.

At large data centers, the cabling administration is typically consolidated at cross-connects, and four connections would be used in channels. These configurations are typically referred to and tested (with the cords) as a channel. There are two configurations, a cross-connection with a consolidation point and a double cross-connect. The consolidation point configuration (Figure 9) allows for two levels of administration to the server equipment, as in Figure 8 on the previous page, but also provides a cross-connect for the switching equipment. The consolidation point may be useful for flexibility, allocating horizontal capacity to many small customers that must be independently maintained.

22: Figure 10: Example of 4 Connector Cross-connect to Cross-connect.

Figure 10, showing the dual cross-connect configuration, is a classic backbone configuration. It provides uniform administration and is suited for large corporate data centers. This configuration is also applicable to backbone cabling from the Main Distribution Area.

23: "Design Advantage" Summary.

At CommScope, we have applied our unique technology to help our customers succeed in the deployment of Category 6A infrastructure. We now offer the shortest channels, backed by our guaranteed performance claims and our design and installation guide. Together, these factors provide customers with the key to the design freedom they have been asking for.

24: That Completes This Lesson.

Welcome to Building Backbone Design - Applications.

2: Copper Backbone.

Let's start with the engineering considerations required for copper backbones. We have already discussed copper backbone design in terms of sizing and topology and have seen that distances for voice backbone applications may be to 2000m, but this will depend upon the choice of switching equipment and signaling systems. BAS backbone support will vary enormously and may be proprietary, but with voice applications and modern IP-based BAS applications moving onto the LAN, copper-based LAN backbones should be specified using high-performance cables, such as Category 6A which will in turn limit them to 90m links and 100m channels. So, fewer multi-pair backbones are being specified, but let's just consider the use of multi-pair cables in a backbone in case your design requires it.
If you recall, when we were sizing the riser cable in step A, we were warned that we needed to consider which signals can share the same sheath or binder group, as this will impact the size of riser cable. When considering signal compatibility, cables of greater than 25 pairs, each individual 25-pair binder group has essentially the same electrical characteristics as individual 25-pair cables. View each 25-pair binder group in the multi-pair cable as a separate 25-pair cable (sheath). Therefore, incompatible signals may be transmitted within the same cable by isolating them within separate binder groups.

3: Copper Backbone.

Some shared sheath guidance can be found in IS11801 and TIA-568 standards, but it is limited due to the complexity and variation of the topic. Some vendors do produce detailed mixed signal (shared sheath) guidelines. Issues to consider before sheath-sharing strategies can be successfully deployed include: transmit amplitudes, signal levels, robustness of protocols and receiver sensitivity. As a best working practice, consider the following.
Applications with different frequencies tend not to interfere with each other. The majority of voice applications (analog and digital PBX and key system circuits) will co-habit within the same mixed sheath. A 25-pair Category 5e binder group can support six 1000BASE-T applications or twelve 100BASE-TX applications. No signals with significantly different power levels should be placed within the same binder group. And finally, do not mix unbalanced (usually legacy) systems with balanced signalling systems.
In short, it is good design practice to size copper backbones to allow for differing applications to run on different multi-pair binder groups and the administration (panel design) should also consider the management and maintenance of this objective.

4: Fiber Backbone.

Increasingly, today's backbones are moving towards fiber, both for distances and application performance. So, let's now look at the more complex environment of fiber channel design and engineering. We have seen that TIA, ISO and CENELEC provide some application distance guidance.

Selection of the fiber media will be based upon the bandwidth, those applications to be supported now and in the future, the distance, the topology and the cost of interfaces. We discussed the implications of the latter in an earlier part of the course and we know that multimode interfaces are less expensive than single-mode. This is very significant in horizontal designs, such as in a data center, where hundreds or thousands of interfaces are required. It may be less significant in backbone design, especially in the campus where fewer links are the norm.
Remember you need to consider the design's longevity so it supports current and future planned applications, for example 25GB or 40G Ethernet today and 100GB or 400GB Ethernet in the future, may be the objective. This, combined with the backbone distances required and interface costs, will help you decide which fiber and connectors are going to be used. We discussed such applications in the standards section of this course. Remember, unlike campus, backbone distances within the building are generally fairly short.

5: Fiber Backbone.

So at this point in the backbone design you or the specification has selected the fiber type to use, the appropriate or practical backbone architecture between rooms, the patching/connectors and any splicing positions, and you have worked out the physical distances for the backbone run along the containment. So the next step is to make sure that the proposed applications such as 10GBASE-SR will operate over that fiber media through that number of connectors and over that distance.
The answer to this is not quite as simple as you may think, as the application drive distance is affected by the media it is running on and amount of attenuation in the channel which is a combination of the losses in the fiber, connectors and the splices. This total is referred to as the power budget for the channel. It can be estimated in advance at the design draft stage and there are two reasons why this is an essential part of the design process:
1. It helps ensure that the proposed channel design does not exceed the power budget supported by the standards for the chosen applications channel. In short the application should work and be within the acceptable error rates.
2. It serves as the benchmark, to ensure that the 'as installed' channel is within the 'as designed' power budget limits. So it is the reference point for post installation testing.

6: Standards Based Loss Allowances.

Estimated power budgets are required to predict the performance of the installed components and to provide a benchmark for testing. These tables show the worst case loss allowances used by ISO and TIA but note they offer different loss allowances on their fiber but the same for connectors. Note that both quote cable attenuation in dB per Km (1000m) and that loss differs depending upon the wavelength. This figure can be used pro-rata. Hardware attenuation offers both insertion loss and return loss figures for connectors and splices. Insertion loss is used in any channel attenuation calculation while the return loss is a factor for vendor connector and termination relevance. You will note the both the mated pair connector and splice allowance is fairly generous especially as it includes both fusion and mechanical splices.

TIA offers a suggested channel calculation: Maximum Length (km) = (Maximum Channel Attenuation minus [(number of connector pairs x 0.75 dB) plus (number of splices x 0.3 dB)] divided by the cable attenuation coefficient. The maximum channel attenuation is taken from a TIA table which relates to each application, and a dB loss figure for either multimode or single-mode fiber.

Question:

Answer: (3.5dB/1000m) x 300m = 1.05dB and 2x 0.75dB = 1.5dB
1.05dB + 1.5dB = 2.22dB


Answer: (3.0dB/1000m) x 500m = 1.5dB and 6 x 0.75dB = 4.5dB
1.5dB + 4.5dB = 6.0dB

11: Step D - Drive Distance Assurance.

So now we have calculated the power budget for our design draft we need to know for a given application if it's acceptable and what drive distance is supported, and for that you have a few options: You can visit the standards application tables found in TIA568.0 or ISO's IS11801. The TIA tables provide columns of applications, each showing a channel attenuation in dB and the supportable distance in meters and feet. In the column entries it includes for OM1, OM2 and 850nm laser optimised OM3 and OM4. There are separate tables for OS1 and OS2 single-mode fibers.

Similar tables are available in the ISO and CENELEC standards. Alternatively the solution vendor supplying the fiber may provide their own tables. Test equipment manufacturers can test channels for given application compliance but of course it's too late by then if it fails, so application drive distance assurance must be completed at the design draft phase.

12: That Completes This Lesson.

Welcome to Building Backbone Design - SYSTIMAX. In this section we will look specifically at the SYSTIMAX backbone components and design advantages.

2: Copper Building Backbone Cable.

SYSTIMAX designs allow the use of both copper cables and fiber optic cables in the building backbone. This graphic shows the copper cables that may be used including 4, 25, 50 and 100-pair cables of various fire ratings. Analog and digital non-VoIP voice applications are typically supported in the backbone by copper Category 3 UTP multi-pair cables which will also support legacy BAS applications. Modern BAS applications however may require a higher category of cable.
Most intra-building backbone distances are actually quite short, so with floor heights between 3m and 4m, 100m covers many floors in a vertical riser design. It is always worth considering running high-performance copper cables between the ER and TRs such as GigaSPEED X10D 91 series cable which will support 10GBASE-T, as long as the channel distance does not exceed 100m, as this can offer some additional flexibility being low-cost to install. However, CommScope primarily recommends a fiber backbone infrastructure, as this will provide optimum longevity and flexibility in design. SYSTIMAX offers one higher-performance 25-pair cable, the 61-series 25F PowerSUM Category 5e cable. This cable is used in horizontal zone cabling and in backbones to support 1000BASE-T over the full 100m channel. Each cable supports up to six 1000BASE-T channels. The advantage of these cables is that they are compact and easy to install.
The 5000-series 4 pair cables offer reduced toxicity and acidity, and low smoke for improved fire safety. They are halogen free and RoHS compliant, making them environmentally friendly. These cables are dual-listed as CMR and CM-LS and offer an extra measure of verification for limited smoke and compliance to the NEC hierarchy for fire safety tests.

3: Fiber Building Backbone Cables.

There are essentially two types of SYSTIMAX fiber cables for use in the building backbone infrastructure: Premises cables or interlocking armored versions. As an alternative, the ULL pre-terminated fiber solution could be used in some backbone designs. Premises cable is an indoor cable constructed with tight buffered fibers and aramid strength yarns, and is available in Riser, Plenum, and LSZH. These cables are designed for point-to-point applications and provide a high level of protection for fibers.

They are available in a single unit of up to 24 fibers and multi-units for higher fiber counts, as well as in a composite mix of the different fiber types.

4: Building Backbone Cable Construction.

This graphic shows the single unit (up to 24 fibers) and multi-unit (36 - 144 fibers) construction. The operating temperature range for all CommScope fiber cables is -40°C to 70°C (-40°F to 158°F). For complete details, refer to the eCatalog which contains the full technical specifications of every cable listed, including pulling tensions.

5: Interlocking Armored Building Backbone Cables.

SYSTIMAX Interlocking Armored Fiber Optic Cable is flexible aluminum conduit containing a tight buffered fiber and is ideal for running up through risers. It speeds installation time as it has its own metal conduit jacket which also protects it from excessive bending while being installed and offers superior protection and security, once in place. It can be used in multiple applications include building backbone, zone distribution, raised floor, data centers, and storage area networks.
Vertical markets include: industrial, manufacturing, airports, stadiums, hospitals, education facilities, multi-occupancy risers, military, and any other areas where increased protection and security for the fibers are desired. The aluminum interlocking armor is applied spirally around the premise distribution cable. The armored cable is then jacketed with a sheath that is color coded to match the enclosed fiber type and is printed with the relevant specifications and fire ratings and so on.

6: Cabling & Pathways Estimators.

Now let's look at SYSTIMAX-specific design considerations for the backbone cables. Once the size and quantity of cables and a splicing strategy is known, it will be necessary to determine the number of 100 mm (4 inch) floor sleeves or lateral conduits needed to accommodate the backbone cables. On the CommScope website in the resources/tools and calculator tab, is the Pathways and Spaces Calculator that allows you to estimate how many cables would fit into the containment you have selected, at the fill percentage you require. For mixed cable types and sizes, that you are likely to find in a backbone, the 'multi cable conduit fill calculator' will be more useful and this calculator can be found in the lesson download area.

7: Performance Specification Tables - Vol 1.

Also here and on the CommScope website, are the Performance Specification Tables which include details for both copper and fiber cables. The table shown here is from Volume One of the Performance Specifications. It shows the guidelines for various applications that can be supported within a 25-pair cable/binder group for SYSTIMAX backbone cables, and within 4-pair LAN cables. As a general BAS guideline, individual systems should only sheath-share with like systems and signals. When working with Building Automation Systems (BAS) applications, refer to the appropriate vendor-specific application guide for detailed guidelines.

8: Copper Application Distances - Vol 1.

Of course most of the copper LAN interfaces are limited to 100 meters. But, where the tables for both copper and fiber become invaluable is when you are dealing with the non-LAN interfaces that we find in the Storage Area Network (SAN), mainframe, BAS, and voice applications.

9: Backbone Fiber Distance SYSTIMAX.

Moving on to fiber in the backbone, this graphic shows the three LazrSPEED variants as well as 62.5 conventional multimode fiber. LazrSPEED 150 is specified as an OM2+ fiber but offers a 10GBASE-S distance of 150m. A survey conducted by CommScope a number of years ago of 45 small and 34 large businesses showed that a high percentage of building backbones were well below 200m, so LazrSPEED 150 offers a 10GBASE-S solution and its associated longevity at a very low cost. Trying to upgrade originally installed fibers such as 50 micron or 62.5 micron fibers to run 10Gb becomes cost prohibitive as much more expensive application interfaces need to be used. This graphic also shows that LazrSPEED 550 OM4 fiber can also run lower speed interfaces such as 1000BASE-SX to 1100m so shows it is a versatile fiber solution. Please note that this distance table is a little simplistic as it shows the maximum distances but does not take into account the number of mated connections, number of splices, or type of connector. Later in this lesson, we will look in more detail at channel design.

10: Backbone Fiber Distance SYSTIMAX.

Transmission speeds are on a constant increase in communications, so it is important to perhaps 'sell' a fiber solution to your customer on longevity, where the fiber remains the same and only the equipment on the end needs to be updated.

The chart here shows the supported distances for the proposed applications. Looking forward to 40G and 100G solutions by promoting the correct fiber now, such as the OM4 (LazrSPEED 550) could pay dividends in the future. Building backbone capacity could also be greatly enhanced with the use of OM5 wideband multimode fiber, allowing familiar duplex topologies to support 40G and 100G duplex links with distances of up to 400 meters or more.

11: Fiber Performance Specifications.

The performance specifications in the download area of this lesson is a really useful document. It can help you at the design stage, to confirm that your new cable and connector choice will run the application, 1Gb or 10Gb for example, over the distance required. It can also help if you are looking at the customer's existing cable and they are asking if they can upgrade their existing fiber link from 100Mb to 1Gb (1000BASE-SX) out to their remote building. They have told you the total distance is 284m according to their old test documentation, over two runs of OM1 external fiber with SC spliced pigtails. Yes, your first reaction is to tell them it won't work but this document will confirm it to the customer.

Table 9 here shows that the maximum distance on this type of fiber is 245m with 4 connections and 4 splices, so they will have to buy a new one. They want to keep their patch panels so what type of fiber would you suggest they install? This is an easy solution. We know that OM3 LazrSPEED runs 10G to 300m, so looks ideal, but we will come back to that later.

12: Fiber Channel Design.

To accurately calculate the fiber losses on a link though, the SYSTIMAX Fiber performance calculator is an essential designer's tool and must be used as part of the warranty documentation. It is very easy to use. Having opened up the zip files and of course read the instructions, the XL Calculator file can be opened. It is fairly intuitive. At the top here we have entered the name of the link and the racks it is connecting between. Select the fiber type and length, so in this example we have made it 100m. Now we need to move down to look at the connector types at each end. We are going to use LC Standard Loss connectors here at both ends. One end will be hand polished and the other end spliced. Click on the connector type and it will jump into the link at the bottom of the page. Now that has been done, you are presented with your completed calculated losses. Note that an allowance of 0.25 has automatically been made for test set uncertainty as well.
Losses are shown at 850nm of 1.36 and also at 1300nm of 1.16. You will need both of these results as this link is a backbone so it needs to be tested at two different wavelengths. The calculator has a second page to the spreadsheet and allows you to save and print off the results so they can be given to the engineers to ensure their losses when testing are equal to, or less than those calculated.

13: Fiber Channel Design.

The other great thing about this calculator is that it is combined with the Performance Specifications, showing instantly the applications it is guaranteed to run. This is a great selling tool and can be shown to the customer as part of the tender or quotation. So the link required here will be 90m and the baseline fiber to install for short distances internally is OM3 LazrSPEED 300 fiber. Not only will this serve the customer's 10G immediate requirement but this calculator will also prove to him that the fiber being installed will also run to 40G providing a long term upgrade path in the future if required.

14: Fiber Channel Design.

Let's return to that scenario we were discussing earlier using the customer's existing cable. The customer wants to run a 10G channel over a 284m fiber link, via 4 SC patch panels using fiber pigtails spliced on to the external fiber. What options do we have? Download the Fiber performance calculator from the lesson download area and work out what is the best solution. The webcast will pause while you do this. Click next to restart.

15: Fiber Channel Design.

If you did the exercise, you would see that spliced SC connectors onto OM3 fiber would not meet the application assurance distance requirements. This leaves you with two options. If they were determined to keep their SC patch panels you would need to change the fiber to OM4 which would then run to 450m. Alternatively you could change the customer's patch panels to LC and then this would give them everything they need. LC connectors have much lower losses than SC's and when you are on the limits of an application's distance this can often help. There are also no real benefits available to the customer by using OM4 fiber either, looking at the faster applications shown here. Both the LazrSPEED OM3 and OM4 offer a 10G solution.

16: Fiber Channel Design.

Just another thing on this calculator, both LazrSPEED OM5 and TeraSPEED fibers use the ULL (Ultra Low Loss) SYSTIMAX pre-terminated fiber solution, so by selecting either of these fibers a new selection of connector types becomes available. These are shown here. The ULL solution is mainly used in data centers or high end computer rooms where multiple fibers are used to link equipment together.

17: Link Loss Calculator.

A more familiar calculator might be the original SYSTIMAX Link Loss calculator. It is similar to the Fiber Performance Calculator and rather than being graphical it offers you a spreadsheet type interface where you can select the fiber type, connectors and number of splices etc. Compared to the Fiber Performance Calculator we looked at earlier, it doesn't display whether your chosen application is guaranteed to run over the link you have created. You will still need to refer back to the Performance Specifications document to check this. Both of these calculators will give you the same results though and should be used as part of your warranty and test documentation. This calculator is also available in the lesson download area.

18: Calculate this Loss.

So as both of these calculators are easy to use, download the one of your choice and calculate this link. Press next to continue when you have worked out the loss!

19: Calculate this Loss - Results.

Here are the results from both calculators. There was 333m of LazrSPEED 150 fiber, 4 SC connections and 2 SC spliced connections. Same either way: -4.27dB loss.

20: Records.

Remember that when you are making these calculations as part of a project, you need to print and keep them for your records and for the installers to test against. You must also submit these records with your SYSTIMAX warranty application.

21: That Completes This Lesson.

Welcome to Campus Backbone Design - OSP Cable and Component Selection.

2: Choosing the Right Campus Cable.

The majority of OSP building connections are now made using fiber. Category 3 copper multi-pairs are still sometimes used for voice but there are also Category 6 and 6A OSP cables for smaller external links such as connecting to a gatehouse or weighbridge. For OSP fiber, there is much more choice, multimode OM2, 3 or 4 or single-mode OS1a or 2. Fiber construction is either loose tube or tight buffered and in a previous lesson we learned that tight buffered is suitable for vertical riser cables but it tends to have a slightly higher attenuation, while the majority of cables installed in campus are loose tube construction, taking advantage of the improved attenuation and the ability of the fiber to flex more easily during the rigors of duct or aerial installation. OSP cables are constructed with either a medium or high density polyethylene jacket, are black with a carbon component in their jacket to help resist UV radiation. Being OSP rated they are designed for external use either on cable trays, direct buried, in ducts or suspended aerially and have moisture barriers to prevent the ingress of water, and these are either 'gel filled' or what is referred to as 'dry fill' construction. Dry filled cables are much faster and cleaner to work with so always check the supplier's specification.

3: Campus Backbone Cable Selection.

Selection of fiber campus backbone cables can be made using the eCatalog. Select the type, indoor/outdoor, outside plant, drop or hybrid and like most eCatalogs, using the drop down menus you can fine tune your requirements right down to gel filled or gel free. Armored cables with steel armor underneath the MDPE jacket offer the highest level of wear and tear and also rodent resistance, while some armored cables can have steel strength members built in. Remember, the steel tape armoring only makes the cable construction rodent resistant, not rodent proof. If rodents are determined, they will gnaw through anything to get at what they want. Once you have narrowed down your choice, a colored specification sheet can be printed off if required. Consult your local CommScope representative should you have concerns or unusual physical requirements for OSP cables.

4: Campus Backbone Cable Selection.

This is the one of the toughest OSP campus cables available. Starting with the 250 micron fibers in the central gel-filled tube, this is over-coated with corrugated steel armor. Alongside that are steel strength members on each side of the cable which is then over-coated with a medium density polyethylene jacket. This cable needs a certain amount of end preparation, including grounding clamps, fiber splitters, and core sealant to prevent the gel from leaking out.

5: Campus Backbone Cable Selection.

An alternative fiber is an armored loose tube stranded construction having 250 micron fibers in 2.5mm dry fill tubes surrounding a central fiberglass strength member. The black jacket on this particular fiber is HDPE (High Density Polyethylene Jacket) over the steel armor. The choice of fibers and constructions is sometimes almost down to customer choice and their budget, but the product specification sheets are ideal to help them make their decisions.

6: Fiber Drop Cables.

Fiber drop cables are an excellent choice if you are looking specifically for a lower-count cable. These can be found in the CommScope Drop Fiber section of the eCatalog. These non-armored, gel-filled cables may be useful in some applications, as they include some that are riser rated, which means they will be suitable where you have long vertical sections of cable run. Again, carefully narrow down the options and check to make sure it is exactly what you require.

7: Fiber Drop Cables.

Aerial self supporting cables have a figure 8 construction containing the fibers and a metallic messenger wire. They are available in both OSP and drop styles. Their construction is always gel-filled loose 3 mm tube with 250 micron fibers, as they are designed to cope with lateral movement. The messenger wire can be removed along parts of the route where suspension is not required. The armored version, with corrugated steel armoring and water-swellable tapes, is shown here but a dielectric (non metallic version) is also available.

8: Campus Overview.

Indoor/outdoor cables have the advantage that they can be run in the buildings without the same restrictions as outdoor only cables. The advantages here are that many of these are riser, plenum or LSZH-rated, meaning they can be pulled between buildings, from EF to EF, without any inline connections or splices. This can be advantageous if you are working with a limited power budget, as reducing the number of connectors will minimize attenuation. Fiber counts for these cables are from 2 to 144.

9: Campus Overview.

This is an indoor/outdoor stranded loose tube cable. In contrast to the one we have just seen, this is a metallic indoor/outdoor loose tube with 2 mm gel-filled tubes and 250 micron fibers. Water-swellable tapes are included, as water ingress into a fiber cable can cause serious damage.

10: Campus Overview.

Another indoor/outdoor option is the interlocking armored cable we saw earlier in the backbone lesson. As we said then, this is available in a variety of fiber types and the different options can be found in the eCatalog.

11: Campus Overview.

The fibers we have seen so far have been armored, but non metallic (dielectric) versions of indoor/outdoor cables are also available. This is dielectric indoor/outdoor tight buffered version, with 900 micron buffered fibers around a plastic coated central strength member. The advantage of this construction is there are no metal components, so no issue with ground potential or bonding considerations. Looking at the smaller cables, with fiber counts of up to 24, the construction is similar to standard premises cables, with kevlar strands supporting and protecting the fibers inside the sheath. These cables feature a UV-stabilized black jacket. Several versions are available, including plenum and LSZH, so this cable can enter the building and depending on the AHJ normally be placed into a riser without having to be spliced to a suitable indoor building cable.

Question:


14: Outside Plant Cable.

So far, we have only discussed fiber OSP cables. But CommScope also offers two 4-pair copper OSP cables. SYSTIMAX Category 6 outdoor 1571 cable consists of eight polyethylene-insulated conductors that are tightly twisted into four pairs. The pairs are stranded around a polyolefin fluted central member, filled with a flooding compound, and covered with a black polyethylene outer jacket. The 1571 cable is fully compliant with the Category 6 requirements of TIA-568 and ISO/IEC 11801. 1592 is a Category 6A F/UTP OSP cable and has the same gel filled construction as the 1571. Termination of this cable would be to the Shielded HGS620 F/UTP connector.

15: OSP Closures.

Returning to the subject of fiber, there may be instances where fibers need to be spliced mid-route because of damage and it is more practical to splice than to replace the entire cable. The FOSC 400 range of closures combine proven fiber management hardware with a highly reliable sealing system, so they not only are they easy to install but are designed to also allow for simple re-entry, making them practical to use in telecom environments. These units are available in a variety of sizes and are designed for use with any cable construction (loose buffer tube, central core tube, loose fiber, and ribbon), in any environment (aerial, pedestal, buried, handhole, and manhole), and for numerous splice applications (express, tapoff, branch, and repair).

16: Building Entrance Enclosures.

CommScope offers a range of products for housing fiber connections at the point of entry into buildings. This WBE-FXS is a metal cabinet with a sealed, lockable front door that can hold up to 864 fusion splices. It can also be used for multi-pair copper OSP cable termination.

17: Campus Overview.

This smaller wall-mounted building enclosure (WBE) is another option. In many instances, you will be required by codes or cost to complete the transition from OSP to indoor as close to the cable entrance position as possible. This metal enclosure can be used for a combination of splicing and termination of fiber optic building cables, OSP cables, or even pre-terminated fibers. There are three models to choose from, depending on the density required, with either 2, 4, or 8 modular cassette or adapter panel positions. They have a strain relief fitting for securing the cable and can be independently secured with a padlock.

18: Grounding of OSP Metallic Cables.

We mentioned the need for grounding metallic cables as they come into the building and this is exactly what the 12A1 clamp kit is designed for. The kit contains not only the grounding fittings but also clamps, allowing the cable to be securely fastened to the side of the fiber shelf or a wall. The 12A2 clamp kit is designed for non-metallic cables so does not include the bonding and grounding hardware.

19: Indoor Termination of OSP Fiber Panels.

OSP cables will normally require consumables kits. Apart from the 12A1 clamps that may be needed, 900 micron buffer tubing must be installed over all 250 micron fibers from the core tube to the connector, if the fiber is to be direct terminated. This tubing is not required if the fibers are to be fusion spliced. If using central tube cables, a splitter kit must be used to group the fibers into bundles in 3mm tubing and then 900 micron buffer tubing for each fiber is required for direct termination. For stranded loose tube cables with fibers in 2.5 or 3 mm tubes, there is a pre-assembled breakout kit that has integral 900 micron buffer tubing. Remember, gel-filled fiber cables will also require sealing with B-Sealant to stop gel leaking out. When estimating costs, the designer will need to account for these items, in addition to pre-terminated pigtails or field-installable connectors and consumables.

20: That Completes This Lesson.