ENTERPRISE EQUIPMENT STRUCTURED CABLING: Get Past Cat 5e

Delhi has managed to avoid a traffic catastrophe, thanks to the large number

of highways that have changed the skyline of the capital city. The same can’t

be said of other metros though, where traffic is comparatively a snarl.

Enterprise data traffic too is growing at an alarming rate. It is estimated

that it could soon be doubling every 18 months.

Is the data highway aka bandwidth there in place to take the impending load?

That’s the question that network managers keep visiting on a periodic

basis. Finding the right answers to this and other related questions is what

will help enterprises avoid jams in their network.

Technology

Trends



The structured cabling market has been witnessing technology swings for a

year or so. The erstwhile prevalent Cat 5 standards have been totally replaced

by the Cat 5e as the default standard.

So far, Cat 5e cabling has been able to take care of various network

application needs of enterprises. Times are changing though….

Soon, as newer applications begin pushing the limits of Cat 5e, the standard

may not prove a choice good enough. True, some vendors have packed more

enhancements into the standard and therefore such installations will be able to

service the needs better, and longer too, but then that’s not going to be a

very long term solution.

In particular, as streaming media applications such as video and multimedia

become commonplace and spawn new applications, enterprises will feel the need

for the higher bandwidth offered by Cat 6. This is exactly what happened in the

early ’90s when the higher bandwidth of Cat 5 cabling compared to Cat 3 caused

most LAN applications to choose the better media to allow simpler,

cost-effective, higher-speed LAN applications such as 100 BASE-TX.

As far as LAN is concerned, standards committees are already working on 10G

BASE-T and the fact is that they have ruled out Cat 5e as the underlying support

infrastructure. That should make the alarm bell ring in the minds of network

managers! It, therefore, makes sense to plan for Cat 6-based deployments.

Enter the fiber….



Big-bandwidth Fiber: Fiber has the capacity to carry much more data at a

better speed as compared to copper. It offers potentially unlimited bandwidth.

In the past, fiber was not so popular due to its high cost. Things, however,

have significantly changed today. Moreover, as the trend of

gigabit-to-the-desktop in the horizontal run catches up, fiber will increasingly

become the preferred choice for campus-wide backbone applications too.

Fiber-to-the-desktop is getting popular among end users, mainly due to the high

speed it offers.

Copper vs Fiber: Trends indicate that in years to come, the choice for

enterprise-wide backbone will become equally distributed between copper and

fiber and many organizations will use both fiber and copper for their vertical

cabling. However, the main reason for continued usage of copper will be economy–copper’s

cheaper and easier to implement than fiber.

Globally too, as reported by various market research firms, a long inning is

indicated for copper. A majority of users don’t see copper becoming obsolete

even after 2007. Quite many see it going strong for another five years.

Moreover, the constant technological improvement on the copper front means a

prolonged life for the medium.

Backbone over Fiber?: Depending on the network usage and the kind of

applications, the choice of the backbone cabling system can be determined.

Multimode fibers are the preferred choice in most of the network designs today.

Multimode fiber (both 62.5u and 50 u) offers virtually unlimited bandwidth to

the entire network. The second choice for the backbone is 100 Ohm Cat 5e cables

in multiple runs. This is a comparatively economic solution.

The most popular horizontal cabling system today is Cat 5e or Cat 6 UTP. Both

these systems are capable of carrying data in the gigabit speed range. Fiber

(two-core) is also seen in a few applications in the form of fiber-to-the-home (FTTH).

Cat 6 versus Cat 5e: Although Cat 6 cabling is taking a major ground

as against Cat 5e and would completely dominate in near future. However, major

deployments of Cat 5e cabling products are still going on. The continuing

popularity of Cat 5e may be attributed to its capacity to deliver the gigabit

speed. It is also a very reasonable solution, something that’s a major

criterion in most projects.

Buying Tips

Look at the Layout First: Enterprises need to keep the physical layout and

structure in view when doing the procurement. An implementation plan can

typically have these components: vertical cabling; horizontal cabling, the

backbone media, and user points.

When enterprise locations are spread over two or more nearby buildings, it

calls for external cabling.

Internal cabling takes care of intra-building needs, and can be across

various floors (vertical cabling) or floor-wise (horizontal cabling).

Map Requirements to Technologies: Costs can be optimized, without

compromising on the performance, by opting for different levels and types of

technologies.

For example, it’s better to install a fiber-optic backbone to interconnect

the buildings. Additionally, there can be some coupling with multi-paired copper

telephone cables for the connection of buildings with the public telephone

network and the provision of internal lines/services between buildings.

Internal Cabling Needs Special Attention: Internal cabling should be

designed in such a way that it’s able to meet present as well as future needs.

This is because the internal cabling is much more complex than external cabling

and an improper plan can make a future expansion a big nightmare. In other

words, the infrastructure should be fully extendable, especially in terms of

technologies.

Ensure Robustness: Robustness of a structured cabling solution should

be high on the buyer’s priority. That comes from the solution’s ability to

facilitate smooth and uninterrupted heterogeneous traffic while ensuring high

network uptime.

’Cause You Can’t Dig It Every Year…   Life to cost ratio: The cabling infrastructure is expected to last far longer than software or hardware. A good cabling infrastructure will therefore need to reflect a lot of vision regarding future applications and yet be cost effective

Look at Fiber’s No-interference Advantage: Fiber is completely

future proof. It remains unaffected by EMI and RFI effects. Two core

tight-jacketed cables are normally used for these applications. Mostly multimode

62.5u fiber goes in multi-storied buildings as a vertical backbone and 50u laser

graded or single-mode fiber goes as a horizontal backbone in the big campus-wide

projects.

Make It Future-proof: In years to come, since the gigabit reaches to

the desktop, the necessity of 10-gigabit backbones will be a must thing for the

bandwidth-hungry applications. With 10-gigabit backbones installed, companies

will have the capability to begin providing gigabit Ethernet services to

workstations and, eventually, to the desktop in order to support applications

such as streaming video, high-end graphics etc. As the speed and bandwidth of

the network increases the distance that copper cable can support decreases. If

looking at a very long-term plan, it will be a good option to use single-mode

fiber since it will be a much superior solution at a relatively much lower cost.

Real-time cabling management could be very effective in the premises

networking where different groups use the same backbones and share the same

resources. It’s very essential to identify the various groups and provide them

the set up and bandwidth accordingly.

For major projects, sophisticated gigabit solutions are also available. Large

enterprises may find such solutions more suitable.

It is also important to note that cabling infrastructure is generally

considered a 10 year investment as opposed to two or three years for

electronics.

Future Trends

Cat 6 in the horizontal and fiber in the backbone will be the most popular

trends in near future. Bandwidth-hungry applications in some enterprises may see

fiber going till the desktop. Among various fiber options, laser-graded

50-micron fiber and single-mode fibers may gain more popularity as compared to

the conventional 62.5 u fiber.

In fact, five years down the line, fiber will start taking over copper as the

dominant medium in the backbone. Yet, fiber-to-the-desk is not likely to become

a reality (as the needs in general won’t be such) over the same time period.

Some FAQs Developed by the Category 6 Consortium

What is the difference between enhanced category 5e cable rated for 400

MHz and category 6 cable rated for 250 MHz?



Category 5e requirements are specified up to 100 MHz. Cables can be tested

up to any frequency that is supported by the test equipment, but such

measurements are meaningless without the context of applications and cabling

standards. The Category 6 standard sets minimum requirements, up to 250 MHz for

cables, connecting hardware, patch cords, channels and permanent links, and

therefore guarantees reasonable performance that can be utilized by

applications.

If we use a Cat 5e RJ45 connector and connect it to a Cat 6 UTP cable,

will the installation be Cat 5e or Cat 6?



By definition (of the standard), it will be a Cat 5e channel. The actual

performance will probably be somewhat better, but nowhere near Cat 6

requirements. Of course, you can set up a channel using any components and

measure it using a Cat 6 (level III) compliant tester, and if it passes, it is

Cat 6 performance compliant. It would not be standards compliant however,

because the components have requirements in and of themselves to assure

interoperability with other Cat 6 components.

Why did Cat 6 cables use to have a spline earlier?



Some Cat 6 cable designs have a spline to increase the separation between

pairs and also to maintain the pair geometry. This additional separation

improves NEXT performance and allows Category 6 compliance to be achieved. With

advances in technology, manufacturers have found other ways of meeting Cat 6

requirements. The bottom line is the internal construction of the cable does not

matter, so long as it meets all the transmission and physical requirements of

Cat 6. The standard does not dictate any particular method of cable

construction.

Is a Cat 6 connector also an RJ45 and will it fit into a Cat 5e socket?



The physical dimensions of the Cat 6 connector interface are identical to

Cat 3, Cat 5, and Cat 5e modular connectors and are fully backward compatible.

What will happen if one mixes and matches different manufacturers’

hardware?



If the components are Category 6 compliant, then you will be assured of

Category 6 performance. Consult the manufacturer for specific warranty

provisions that may be applicable.

How Cat 5e and Cat 6 Compare…

The general difference between Category 5e and Category 6 is in the

transmission performance and extension of the available bandwidth from 100 MHz

for Category 5e to 200 MHz for Category 6. This includes better insertion loss,

near end crosstalk (NEXT), return loss and equal level far end crosstalk (ELFEXT).

These improvements provide a higher signal-to-noise ratio, allowing higher

reliability for current applications and higher data rates for future

applications.

Because of its improved transmission performance and superior immunity from

external noise, systems operating over Category 6 cabling will have fewer errors

vs. Category 5e for current applications. This means fewer re-transmissions of

lost or corrupted data packets under certain conditions, which translates into

higher reliability for Category 6 networks compared to Category 5e networks.

The Connectors: Although Cat 6 and Cat 5e connectors may look alike,

Cat 6 connectors have much better transmission performance. For example, at 100

MHz, NEXT of a Cat 5e connector is 43 dB, while NEXT of a Cat 6 connector is 54

dB. This means that a Cat 6 connector couples about 1/12 of the power that a Cat

5e connector couples from one pair to another pair. Conversely, one can say that

a Cat 6 connector is 12 times less ‘noisy’ compared to a Category 5e

connector. This vast improvement in performance was achieved with new

technologies, new processes, better materials and significant R&D resources,

leading to higher costs for manufacturers.

Source: www.tiaonline.org

Why not Skip Cat 6 and Go Straight to Optical Fiber?

One can certainly do that, but a fiber system is still very expensive.

Ultimately, economics drive businesses, and today optical fiber together with

optical transceivers is about twice as expensive as an equivalent system built

using Category 6 and associated copper electronics. Installation of copper

cabling is more craft-friendly and can be accomplished with simple tools and

techniques. Additionally, copper cabling supports the data terminal equipment (DTE)

power standard developed by IEEE (802.3af).

PCs ship with copper network interfaces included, in fact, recent

announcements indicate that the major PC vendors are shipping 10/100/1000 with

all new systems. Moving to fiber would mean buying a fiber-based network card to

replace equipment already included in the PC.

The Category 6 Consortium is an emerging working group whose mission is to

create market and industry awareness–as well as demand–for cabling systems

and components based on TIA’s new category 6 cabling standard.

Source: www.tiaonline.org