Wire on fire
With all the advancement in technology and need for speed
you'd think it was time for copper cables to be ousted.
is it? As it turns out, the new improved
copper cables may be the all-in-one solution your business
needs. by Rajesh Kumar
The second edition of ISO/IEC 11801, IEC 61076-3-104 and IEC
60603-7-7 has led to a fully defined and complete standard for Category 7/Class
F systems. Earlier, with Unshielded Twisted Pair cabling, cables within one
shield could not perform more than one function. With the standardized cabling
however, each pair within the cable is shielded. Hence, each pair can run its
own application without disrupting other pairs.
The international standard IEC 61076-3-104 was published and specified for class
F cabling in ISO/IEC 11801 and for BCT cabling in draft ISO/IEC 15018. The connector
uses a quad design with one pair terminated in each internally isolated quadrant.
This enables a host of configuration options within the same cable thanks to
the availability of existing and emerging applications. Users need to consider
that one pair of cables is needed for phone service, two for 10/100 Mbps data
transmission, and just one for video or other applications.
Workstations are generally equipped with two cables, one for phone and one for
data. The telecommunications outlet invariably has all four pairs on one cable
terminated for use with 1Gbps operation. It will probably be forward compatible
with a 10Gbps operation once the standard is drafted. A second four-pair cable
can provide a variety of other applications such as phone, powered Ethernet
devices and video-conferencing. The shielding within an Shielded Twisted Pair
(STP) otherwise known as a Pimf (Pairs in metal foil) style cable virtually
eliminates cross talk between pairs allowing "noisy" applications
to function without disturbing other services running on the same cable. So
it blocks all disturbances outside from entering and prevents leakage of what
it is carrying inside. This is particularly important in environments such as
plant floors where equipment produces high levels of Electromagnetic Interference
Applications Driving the Demand for Cat7/Class F
A relatively new application is xDSL television broadcasts. Phone companies
are beginning to realize that VoIP (Voice over IP) services are causing a shift
in their profit structure. The ability to provide television over xDSL lines
opens an additional revenue stream for service providers. This may well become
a means for teleconferencing and tele-learning application in the future.
The broadcasts use a single cable pair. Broadcasts can be viewed on a PC or
a small television monitor depending on the implementation. The advantage of
having a separate TV monitor is that broadcast viewing and computing resources
can be independent. This could ultimately provide a whole new dimension to collaboration
products. Video on Demand and Broadband Video are expected to be revolutionary
for business. For example, it may enable companies to provide training to employees
at their desktop on demand, which will maximize their training experience. Users
will have the ability to stop and start training sessions, rewind and review
or skip parts they don't require. Plus the company will save travel expenses
and lost productivity during travel. The ROI for these systems is relatively
Videophone technology has now advanced. It has better compression algorithms
and streaming media. These phones operated over a single cabling pair; newer
versions are wireless. It is likely that cabled or not, these phones will gain
popularity as new IP versions are introduced. Possibly, future versions will
include collaboration utilities such as live digital recording of conversations,
or even television broadcasts over the phone set.
More IP Applications
Video surveillance is rapidly growing as companies work to protect their human,
physical and data assets. In addition to transmitting video signals, cameras
can now be powered over Ethernet pairs. The ability to run multiple cameras
over a single cabling channel provides multiple configuration options. It is
possible to add audio to the surveillance through one of the cable pairs. An
additional pair could also be used for biometric authentication (i.e. iris or
fingerprint scanning) and access control. Building Automation systems can now
be implemented over one structured cabling systems and provide for a single
integrated management solution. Fire, life and safety systems, surveillance,
HVAC systems and other building functions could run over the same cabling channels
that typically support voice and data.
In medical environments, the National Electrical Manufacturers Association (NEMA)
created the Digital Imaging and Communications in Medicine (DICOM) standard
as a common denominator for the viewing of medical images. The days of x-rays
are quickly coming to an end. Newer devices provide digital images, which can
be viewed and manipulated via computers rather than being printed on film. With
time and technology these digital images will grow larger. They will require
higher bandwidth and throughput. The ability to provide a shielded solution
in these environments allows an additional level of data protection by isolating
the cabling channel from any noise emitted by the medical scanning equipment.
Data centers and storage area networks are fast becoming highly sophisticated
with new equipment and applications being continuously introduced. Protection
and storage of data is not a luxury but a necessity; businesses cannot function
without it. Data stores are growing exponentially in size. Consequently, the
first 10 Gbps standard was supposed to be adopted last month by the IEEE providing
10 Gbps transfer rates over twinax cabling for short distances. Work has already
begun on a 10 Gbps standard for twisted pair cabling. Category 7/class F cabling
already meets the need for these speeds today and is expected to be a recognized
industry standard for supporting 10Gbps over a full 100 meter, four-connector
Providing multiple services through a single cable channel saves labour and
material costs since fewer cables need to be laid, fewer outlets and patch panels
are needed, less rack space is needed therefore less real estate is required
for telecommunications closets or data centers. In one case study, a company
realized a savings of 66 per cent in cabling materials, 50 per cent in labour,
and gained 332m2 of floor space because of the savings in racks and terminations
in their equipment room. It is thus particularly suited in crowded cities.
What about fiber?
With the bandwidth demands increasing, why not just run fiber to the desktop?
Fiber certainly has its applications. However, one compelling reason for copper
cabling is the ability to provide Power over Ethernet to network devices. Wireless
Access Points (WAPs), phones and a myriad of other devices are either on the
market or coming to the market allow for low voltage power to be supplied via
a switch rather than a separate power outlet. The real advantage to this technology
is provided through enhanced up-time during power outages. The switch, equipped
with backup power, would allow the communication systems to run even when the
building's power is out.
Cost is another criterion. Application sharing over one cable/outlet is not
possible with fiber electronics at the work area. Fiber devices and network
cards are more expensive than copper. While there certainly are applications
where the cost can be justified, it is not usually the case. Fiber to the desktop
does not eliminate the need for copper cabling for phones and other equipment
that may needed at the work-area. Some organizations are opting for the best
of both worlds and while extending the life of their cable plant by providing
one or two Category 7 cables and one dark fiber to each desktop. Certainly,
whatever option a company decides upon will be based upon individual needs,
budget constraints, and a look into a crystal ball to determine the future possibilities.
With the speed limitations of the last mile becoming extinct, applications have
more room to grow than was possible just a year ago.
Rajesh Kumar works in Siemon Cabling. he can be reached