STRUCTURED CABLING: Superior Technology, Lower Prices



The biggest worries for network administrators are downtime and lack of
repeatable, installed performance. Researches have pointed out that more often
than not inferior cabling system is the cause. This is ironical, given the fact
that the structured cabling system investment is about just five percent of the
total network investment and it outlives most of the other networking
components.

Ironical still is the lack of attention for the selection of cables for the
network. The more visible and relatively hi-technology connectivity components
attract most of the mind share. The fact is that cable quality is the bottleneck
in most networks, and given that once installed cables are difficult to replace,
this bottleneck remains for the network’s life. Installing standards-compliant
structured cabling systems can reduce downtime to a large extent. Of course,
what is important here is that networks remain standards-compliant post
installation rather than under test conditions. For example, twisted-pair cable
must provide the user with superior electrical performance both
“on-the-reel” and in use.

Category 6: As TIA Defines It

The TIA-published document contains Category 6 end-to-end cabling specifications, component specifications, field tester requirements and measurement procedures, together with accuracy and reproducibility guidelines that ensure a reliable cabling system.

l

The standard satisfies backward compatibility with Categories 5e, 5 and 3 standards

l

Allows products from different vendors to work together

l

Patch cord plug-and-jack interoperability for modular (RJ-45 type) connections

l

Full system specification including testing of components, patch cords, channels and permanent links

l Twice the bandwidth of Category 5e with positive power sum attenuation to crosstalk ratio (PSACR) up to 200 MHz
l All specifications for components and cabling are tested to 250 MHz

The user (read enterprise) needs to view structured cabling as an investment
protection. The first step in deploying a structured cabling solution is to
establish the aims of network implementation. Besides software and hardware,
understanding the networking trends helps. Local area network (LAN) technology
has been around for over 20 years. The first decade of the LAN technology
development was on a department basis. It consisted primarily of Ethernet and
Token Ring products that delivered about 200—500 kbps per user. The entire
network was capped at 10—16 Mbps. But today, the corporate computing
marketplace has been almost completely converted to the LAN-based model, with
over 80 percent of all PCs attached to corporate LANs. The rate at which these
LANs process critical information has multiplied and new higher-speed LAN
technologies like switching, multiple 100 Mbps Ethernet replacements, and ATMs
have come to the forefront.

Technology Options

Cat 6 Must-haves…

Following are the top three areas that required new development work for Category 6 specifications:

l

Test plug qualification for near-end crosstalk (NEXT) and far-end crosstalk (FEXT). This is the fundamental basis for plug and jack interoperability between manufacturers.

l

Patch cord performance requirements and test specifications. Patch cord testing is key to ensuring interoperability. This has been included in the Category 6 standard as a fundamental requirement and not as an addendum, as was the case for Category 5e.

l

Measurement procedures for connecting hardware NEXT and FEXT. These procedures required the creation of brand new fixtures, calibration procedures and many refinements to ensure repeatability in different laboratories.

*Source: TIA White paper

n A Single
System:
Today’s structured cabling is a single cabling system (copper or
fiber), which covers the whole building for all voice and data (including CCTV
and video) requirements. A structured cabling system consists of outlets, which
provide the user with an RJ45 extension. The outlets are either one or two RJ45
connectors mounted in a standard single gang face plate, or as single snap in
modules which can be fitted into floor boxes, single gang face plates (up to two
modules) or dual gang face plates (up to four modules). The system enables each
user outlet to be cabled back to a hub using an individual cable of four twisted
pairs of copper. The cable can be Unshielded Twisted Pair (UTP) or Shielded
Twisted Pair (STP), or Foiled Twisted Pair (FTP). And the cable is connected to
the back of the user outlet by means of an Insulation Displacement Connection (IDC)
connector. In India, it is generally the UTP.

Journey to Cat 6: A Timeline
Years Technology
Evolution
1980
lEthernet
IEEE 802.3
lCoax based Bus Physical
Topology
l10Base5 Thicknet
l10Base2 Thinnet Coax
1985
lToken Ring IEEE 802.5
lShielded
Twisted Pair (STP) Ring Physical Topology
lIBM Cabling System–Type 1
& 2
1985
l10BaseT Emerges
lUnshielded
Twisted Pairs (UTP) Star Physical Topology
l2 pair phone cable
(non-standardized)
1991
lEIA/TIA 568
lSets the standard for telecom cables
lPre Category 3
1993
lTechnical Service Bulletin (TSB)
lTSB 36 Cable
lTSB 40 Connecting Hardware–Category 3
lTSB
40A Connecting Hardware–Category
4
& Category 5 and Patch Cord
Requirements
1995
lTIA/EIA
568-A
lRewrite of EIA/TIA 568
lIncluded
Previous TSB’s 1995—1999
New TSB’s
lTSB 67–Field Testing of UTP
lTSB 72–Centralized Fiber
Guidelines
lTSB 75–Open Office/Zone
Cabling
lTSB
95–Additional Testing for Category 5
Cabling
1999
lTIA/EIA Standards Activities
lCategory 5e–Complete
lEnhanced 100 MHz performance
lCategory 6–On 5th Draft
Proposal
l250 MHz Performance
lTIA/EIA 568-B–Rewrite of
568-A
lIncluding TSB’s
lCategory 5e
lOther 568-A Addendum
lRemoves Category 4 and
Category 5
2002
lCategory 6 ratified

Parameters: The most important point about structured cabling is that
every vendor has to conform to the parameters specified by the Standards
Committees like TIA/EIA or ISO. These standards tell you the performance
parameters like how a set cabling system should be and comply with and how the
individual components on the system should measure. The parameters involve:
attenuation, pair-to-pair NEXT, PowerSum NEXT, ELFEXT, Powersum ELFEXT, Return
Loss, Delay Skew, pair-to-pair ACR, and PowerSum ACR. Though all the words are
technical jargons, in short they mean the noise levels rating, the resistance
and data loss as a consequence, etc.

Cable Management: While cables have a very consistent geometry
throughout their length, its when the signal transitions from a cable to a
connector that a potential for discontinuity exists. The use of the cable
manager provides better control over the placement of the wire pairs and
automatically resolves the important issue of keeping the unsheathed wire pairs
as short as possible up to the 45-degree IDC terminals.

Impedance Matching: Impedance defines the best “path” for
data to traverse. For instance, if the signal is transmitting at an impedance of
100 Ohms, it is important that the structured cabling also possess an impedance
of 100 Ohms. Any deviation from this set point will result in part of the signal
being reflected back towards the source of data. Impedance variations can occur
for many reasons. One is from the manufacturing process itself. Any deviation of
conductor-to-conductor spacing or insulation properties will cause impedance to
vary. Another way in which impedance can vary is by mismatched components. In
fact the new Category 6 standard has taken this on board and has brought down
the impedance level from + or – 15 percent for Category 5E to +or- 6 percent for
Category 6.

n Technology
on Copper:
Today one hears mostly about Category 5 Enhanced (Category 5E),
Category 6, and Category 7 solutions. Not going into much detail to what each
Category of systems indicate, it must be mentioned that Category 6 is a ratified
standard today. Prior to June 2002, it was Category 5E that was a ratified
standard, while Category 6 was a draft standard. The other standard, we hear is
the Category 7 standard, which is still an ISO development, and not yet
considered by TIA. Though innovations in Copper cabling are relatively few,
there are differentiated products like bonded pair cable solutions that promise
significantly higher levels of post installation performance.

Category
6 is a full duplex Ethernet Physical Layer specification for 1000 Mb/s operating
over Category 6 Balanced Twisted Pair Cabling (1000 Base-TX.). This means
additional performance parameters for rejection of noise, increased performance
criteria for common parameters like channel attenuation and return loss, and
extended bandwidth from the Category 5.

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 250 MHz for Category 6. This includes better insertion loss,
Near End Cross Talk (NEXT), return loss, and Equal Level Far End Cross Talk (ELFEXT).
These improvements provide a higher signal-to-noise ratio, allowing higher
reliability for current applications and higher data rates for future
applications. Ideally suited to high performance applications such as gigabit
Ethernet, Category 6 has some significant advantages over and above Category 5E
cabling infrastructure. Full characterization to 250 MHz provides for two and a
half times the usable bandwidth of Category 5E systems.

There is already an increased talk about Category 7. This is an ISO
development only, not even considered by TIA. It is proposed ISO 11801 Class F
and addresses bandwidth up to 600 MHz. Category 8/Class G is again proposed ISO
draft.

This is seen as “Broadband Premises Cabling” for 1 to 2 GHz.
However, the proposed channel length would be contained to 50 m. Now that the
Category 6 has so much more and that there are simultaneous developments
happening in fiber too, experts advise not to bother even beyond Category 6.

n Technology
on Fiber:
Two general types of fiber have emerged to meet user requirement:
multimode and single mode. Single mode fibers can propagate only the fundamental
mode. Multimode fibers can propagate hundreds of modes. However, the
classification of an optical fiber depends on more than the number of modes that
a fiber can propagate. An optical fiber’s refractive index profile and core
size further distinguish single mode and multimode fibers. The refractive index
profile describes the value of refractive index as a function of radial distance
at any fiber diameter. The standard core sizes for multimode step-index fibers
are 50µm and 100µm. The standard core sizes for multimode graded-index fibers
are 50µm, 62.5µm, 85µm, and 100µm. Standard core sizes for single mode
fibers are between 8µm and 10µm. In most cases, the material used in the
preparation of optical fibers is high-quality glass.

Market Information

n The Big
Three:
Avaya, Tyco, and D-Link were the major shareholders in the Indian
structured cabling market. Avaya and Tyco, which account for close to 60 percent
of the market share, are continuing to dominate the market. Avaya had about 40
percent market share, while Tyco has about 21 percent. D-Link’s market share
stood at close to 17 percent.

Systems integrators today see Tyco as number one in south, east, and central
India, while Avaya is considered strong in north and west. Meanwhile D-Link,
Krone, Molex, Panduit, and Finolex too are consolidating their bases. This year,
some more international brands like Belden and Nexans could be making their
presence felt.

n Copper Rules
the Roost:
On the technology front, the adoption of latest technology is
gaining momentum. The market is moving from Category 5E to Category 6. Copper is
winning the horizontal battle, primarily because of the cost of components for
100BaseT and backward compatibility to easily support legacy systems. Though
fiber costs will continue to decrease due to economies of scale, the belief is
that there will still be a substantial price premium on fiber components such as
NICs and switches, and potentially much more infrastructure to replace with a
move to fiber. Category 6 standards copper cables promises enhanced performance
of 250 MHz and copper to desktops, which is still cheaper.

n Fiber
Picking Up:
The penetration of fiber in the backbone has been about 30
percent, and rising. The attractive proposition for fiber has come from campus
networks. But fiber to the desktops will take several more years. In India, it
has been the 62.5 micron multimode fiber that has been growing. However, of
late, 50 micron multimode is gaining ground. Single-mode is still sparsely
deployed. It is not because the cost of the cable. Though the cable is cheaper
than the multimode, the electronics required to run on the single-mode are
expensive. Only, telecom companies have been deploying single-mode fiber in
their WANs.

n Price Drops:
In India, most of the cables are still imported and the duty rate too is
high. As a result, significant price drops were not a norm until the previous
years. However, tough market conditions last fiscal saw forced erosion in
prices. The pressure came from the unorganized sector, which offered low-priced
cabling solutions sourced from the gray market. Major vendors made about 10—12
percent reduction on the price front.

n Improved
Channels:
The focus of vendors has been on training and consolidating
channel partners. Vendors like Molex, D-Link, Krone, Panduit, and Tyco focused
on roadshows and education. Moreover, they not only have added stockists and
increased their presence to other cities, but have also looked at becoming total
solutions providers.

n More
Manufacturing in India:
Players like Tyco, Molex, Krone and D-Link are
having their manufacturing plants expanded and are gearing up to provide
products for the global markets. Molex announced that it would be manufacturing
majority of the Category 6 products in India. Tyco too is looking at India as a
big manufacturing base. Europe would be offloading work to India. It would be
manufacturing copper patch chords, fiber optic accessories, and then follow it
up with IOs. India is the No 1 priority for all these global vendors in the APAC
region.

n New Offers: In
line with the standards and even beyond them, players have been launching new
products in copper. For example, Krone launched the TrueNet Category 6 solution
that offers a 100 percent throughput warranty or a zero bit error rate; Molex
will be introducing data patching systems and the patch chords; Tyco introduced
OM3 fiber for gigabit Ethernet and AMPACT system among several other products.
Belden is bringing into India its patented Bonded Pair technology, wherein
conductors in pairs remain attached to each other, ensuring virtually nil impact
of installation stresses. It is also to introduce a product that guarantees
performance up to 600 MHz. Panduit introduced a complete Category 6 solution and
has also launched Panview, an active cable management system.

Buying Tips

n Involvement:
Remember, you get what you spec and inspect, not what you expect! So remain
involved during technical discussions and evaluation. Don’t leave cable
selection to chance or to a party that has vested interests different from your
objectives.

n Technical
Specs:
The technical considerations to keep in mind while designing a
network and choosing components and vendors include:

Lower bit error rate

  • Higher throughput of a system
  • Less network downtime

  • Future proofing

  • Easier installation – “reduced testing time”

  • Easier migration to higher data rates

  • More attenuation & NEXT available for other
    components

To achieve the best results keep the following tips in mind:

n Committed
Brands:
There would be minimal difference between one vendor and the other
for Category 5e systems. But going for branded solutions from those vendors who
are committed to the Indian market really pays off, as cabling is a very
important investment. The point that needs to be kept in mind is to go for the
technology leaders and those organizations, which are part of the international
standards committees. This would ensure that one is not only getting a quality
solution but also future-proofing the investment. Installing a Category 6
compliant network requires much more effort up front to ensure that genuinely
compliant systems are short-listed, and provide installed performance as per the
recently ratified Category 6 standards

n Standards
Compliance:
Standard Complaint solutions are a must. This is because these
standards are independent of both technologies and the vendors. And they are
designed to meet future technology adoptions. With convergence coming to the
forefront, and attention moving towards VoIP in the enterprises, wiring shouldn’t
be an afterthought. Enterprise can migrate to VoIP even if they have a legacy
Categories 3—6 cable with upgrade to 100-Mbps switched Ethernet and above.

The approach to take on standards compliance is “Let The
Manufacturer Hide Nothing”. Obtain written performance values on Input
Impedance and RL; Attenuation; NEXT (including PowerSum); ACR (including
PowerSum); Delay Skew; FEXT/ELFEXT; CAP Unbalance.

Obtain all the data for physical, electrical and mathematical
equations and make an effort to compare and contrast values along with
conducting some actual testing. Some manufacturers publish their products’
best performance as their spec, while the best manufacturers publish their
products’ worst performance as their spec. Stick to the latter category and
you are unlikely to go wrong.

n Construction:
Category 6 cables use 0.59 mm (23AWG) plain annealed copper, polyethylene
insulated twisted pairs, laid up around an internal support X-spline within a
PVC jacket. The internal support spline ensures crosstalk advantages, while
providing support for individual pairs and the cable as a whole.

An ideal pair is comprised of two perfectly balanced
insulated conductors that are mirror images of each other. To achieve this
balance, the centre-to-centre distance, or centricity between the copper
conductors of a pair should remain fixed and constant along the length of the
cable. With Category 6 standards pushing the boundaries of performance for UTP,
users are relying heavily on installation techniques to maintain good
performance from their installed system. Typically, when cables are installed
they are pulled on, bent around corners and may kink. Each of these factors
changes the physical properties of the cable, which in turn can degrade the
cables’ electrical performance. Thus it is important to seek products with
construction that is forgiving to varied installation practices such as coiling,
pulling around bends, and pulling from the box.

n Consider
the Environment:
When comparing various types of cables, it must be
remembered that the results would be dependent on the implementations, such as
the network cards, hubs, and other devices used and depend on the factors like
the cabling distance, physical location, and environmental effects. For
instance, fiber-optic cable maybe costly on a per-foot basis, but may work out
to be cost-effective a cable has to run for several kilometers. All depends on
the repeaters needed to run the cable. Today Gigabit Ethernet has been approved
for fiber optic cable in 550M and 5 km lengths and for Category 5 copper cable
up to 100 meters. It is important to keep in mind the design consideration of a
structured cabling system including building entrance, equipment room, backbone
cables, intermediate and main cross-connects, mechanical terminations and patch
cords or jumpers used for backbone-to-backbone cross-connection.

Global Market: An Overview


According to
BSRIA, the worldwide market for structured cabling, which includes copper and multimode fiber products used in LAN applications is estimated at $4.05 billion (material at manufacturer sales prices) for 2002. The market is expected to increase by an average of 4.4 percent per year between 2001 and 2005. 2001 was a bad year for particularly the USA where the market fell by 25 percent before staging a modest recovery in 2002. Two-thirds of the worlds structured cabling sales are concentrated in six countries: the US, Germany, UK, China, France and Australia. The largest growth potential is however found in Asia in countries such as China and India, growing at over 15 percent per annum. Other countries with rapid growth rates are: Russia, Saudi Arabia and Brazil. 

The world market is dominated by UTP cable, which accounts for 83 percent of the installed cable at horizontal level in 2001, 7 percent is
STP, 80 percent of which is installed in Germany. FTP accounts for almost 10 percent with the largest countries being Germany and France. But the usage of FTP is more widespread and for many countries commands a significant share.

Category 6 has penetrated the market in most countries in 2001 and now accounts more than 25 percent by volume in
UAE, Singapore, Australia, USA, Switzerland, Finland, Germany and the Netherlands. Proposed Category 7 has only reached a small share of the market in a few countries: Switzerland, Austria, Germany and France.

n Engage
Consultants:
Have a draft plan of action and check if the proposed network
architecture is practical. Engaging consultants will involve expenditure, but
may speed the deployment process up by allowing key issues to be quickly
identified, and questions to be directly and independently answered.

n Go
for Good Integrators:
Considering all these parameters, it is advisable to
go for solution providers who have good track record of support and assistance
with a good list of channel partners, installers, and certified professionals.
They could also help in the documentation process. Documentation will help an
unfamiliar person to quickly grasp the network topology.

They can also enable the network to grow in a planned and
well- structured manner. The final performance of your network is highly
dependent upon installation practices. Simple techniques like following the ½
inch rule (“Never untwist pairs more than half an inch at the point of
termination”) can go a long way in ensuring superior network performance.
So ensure that the SI you choose is known to pay attention to detail.

EXPERTS
PANEL

Asish
Chand,
country manager, Belden
DS
Nagendra,
country sales manager, PremisNET, Krone Communications
KK
Shetty,
country manager, NETCONNECT Solutions Division, Tyco
Electronics
Sreelal
Nellary (RCDD),
regional sales and technical support manager, Panduit
Int’l Corp.

Leave a Reply

Your email address will not be published. Required fields are marked *