Transcript Lecture 4

Cabling
Structured Cabling
Standards
Structured Cabling
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Structured Cabling is the foundation for
any communications installation.
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An appropriate cabling installation
ensures the proper operation of
equipment, manageability, organization,
and expandability of a communications
network.
Network Cabling
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In the early 1980's a variety of cable types and
designs were utilized. Coaxial and twin-axial
cables were the most popular.
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Proprietary (non-standardized) designs were
predominant.
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Today cabling and devices have been
standardized in a way which makes them
interoperable and compatible in almost any
implementation.
Standards Bodies
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These organizations are composed of
representatives from various distributors,
manufacturers, and customers in the
communications industry
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ANSI - American National Standards
Institute
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TIA - Telecommunication Industry
Association
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EIA - Electronics Industry Association
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EIA/TIA-568 - first version of the standard published July of 1991.
TSB-36
August of 1991 a Technical Systems Bulletin specifications
for higher grades (Cat 4, Cat 5) of UTP.
TSB-40
August of 1992 TSB-40 published addressing higher grades
of UTP connecting hardware.
TSB-40A
UTP patch cords in more detail, and to clarify testing
requirements for UTP modular jacks.
TIA/EIA-568A/(CSA T529) Commercial Telecommunications Cabling
Standard
EIA/TIA-569/(CSA T530)Commercial Building Standard for
Telecommunications Pathways and Spaces
EIA/TIA-570/(CSA T525) Residential and Light Commercial
Telecommunications Wiring Standard
TIA/EIA-606/(CSA T528) Administration Standard for the
Telecommunications Infrastructure of Commercial Buildings
TIA/EIA-607/(CSA T527) Commercial Building Grounding/Bonding
Requirements
TSB-67
Transmission Performance Specifications for Field Testing of
Unshielded Twisted-Pair Cabling Systems
TSB-72
Centralized Optical Fiber Cabling Guidelines
Commercial Building Telecommunications Cabling
Standard (ANSI/TIA/EIA-568-A-95)
 Committee:
TR-41.8.1
 Published:
October 25, 1995
 Category: Telecommunications
 Description:
This standard specifies a generic
telecommunications cabling system for commercial
buildings that will support a multiproduct,
multivendor environment. It also provides
information that may be used for the design of
telecommunications products for commercial
enterprises. The purpose of this standard is to
enable the planning and installation of a structured
cabling system for commercial buildings
TIA/EIA-569-A
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Title:
Commercial Building Standards for
Telecommunications Pathways and Spaces
(ANSI/TIA/EIA-569-A-98)
Committee:
TR-41.8.3
Published:
October 24, 1990
Category: Telecommunications
Description:
This Standard encompasses
telecommunications considerations both within and
between buildings. The aspects covered are the
pathways into which telecommunications media are
placed and the rooms and areas associated with the
building used to terminate media and install
telecommunications equipment.
Purpose of the TIA/EIA568A Standard
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Establish a generic telecommunications
cabling standard that will support a
multivendor environment
Enable the planning and installation of a
structured cabling system for
commercial buildings
Establish performance and technical
criteria for various cabling systems
configurations
TSB-67
Transmission Performance
Specification for Field Testing of
Unshielded Twisted Pair Cabling
Systems
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TSB-67 defines the allowable worst case
attenuation and NEXT for an installed link.
Scope of the TIA/EIA-568A
Standard
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Minimum requirements for
telecommunications cabling within an
office environment
Recommended topology and distances
Media parameters which determine
performance
Connector and pin assignments to ensure
inter-connectability
The useful life of telecommunications
cabling systems as being in excess of ten
years
The Six Subsystems of a
Structured Cabling System
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1.Building Entrance
2.Equipment Room
3.Backbone Cabling
 Specified Topology
4.Telecommunications Closet
5.Horizontal Cabling
 Specified Topology
 Maximum Distances
 Telecommunications Outlet
 8-Position Modular Jack Pair Assignments
6.Work Area
TIA/EIA 568A Sub
Systems
1. Entrance Facility
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Point where outside plant cables and
associated hardware are brought into the
building.
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Cables from the outside end in an
Equipment Room which is the main
distribution point for the building. This
is often called the BDF (Building
Distribution Frame).
2. Equipment Room
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A centralized space for communications
equipment.
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Equipment Rooms often contain cabling
distribution equipment.
“Patch Panels” and “Cross Connect
Blocks” are used to terminate or end
cables and to connect them with other
cables and equipment.
3. Backbone Cabling
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Interconnections between closets and
equipment rooms within a single
building or between other buildings.
Large buildings may contain several
distribution points or
Telecommunications Closets which
are necessary to overcome distance
limitations.
 Risers are Vertical cable runs which
connect Telecommunications Closets
on different floors.
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4. Telecom. Closet
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A space where horizontal distribution
cables are terminated.
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All cable and media types must be
terminated on compatible connecting
hardware.
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Backbone cables are also terminated in the
closet. Cross connection is done with
jumpers or patch cords to provide flexible
connectivity.
5. Horizontal Cabling
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Physical media used to connect each
outlet to a closet.
Horizontal Cables span from
Telecommunications closets to the wall
jacks with which users connect their
equipment.
 Copper Cables, Coaxial Cables, and
Fiberoptic cables may be used.
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6. Work Area
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Connections and cabling on the other side
of the telecommunications jack.
Horizontal Cabling Distance
Specifications
568A Implementation
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offers voice and data to each workstation
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Mandates 2 jacks (1 for voice 1 for data) per
station
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Voice Jacks 4 pair 100 Ohm Category 3 or
better
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Data Jacks 4 Pair Category 5 or Better or
multi-mode fiber.
Media Types
Unshielded Twisted Pair (UTP) Cable
 Shielded Twisted Pair Cable (STP)
 Single and Multi-Mode Fiber
 Coaxial Cable (Grand-fathered into but
not recognized by the TIA/EIA 568 A
standard).
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Media and Connecting
Hardware Performance
Specifications of the 568
Standard
Media and Connecting Hardware
Performance Specifications
 100 Ohm Unshielded Twisted Pair
(UTP) Cabling Systems
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Horizontal Cable
 Backbone Cable
 UTP Connecting Hardware and Cords
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150 Ohm Shielded Twisted
Pair (STP-A) Cabling
Systems
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Horizontal and Backbone STP-A Cable
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Optical Fiber Cabling Systems
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150 Ohm STP-A Data Connector
150 Ohm STP-A Patch Cable
Optical Fiber Cabling Media
Optical Fiber Connector
Optical Fiber Telecommunications Outlet
TSB-67 Standard
Shielded Twisted Pair (STP)
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Developed by IBM for Token Ring
Rated at 20 MHz
Newer STP 568 A systems can achieve 300
MHz
Electrical Performance of Twisted Pair Cable
Uses electrical signals to carry data
STP cabling systems are more expensive and
harder to install and maintain than UTP
cabling systems, but are not necessarily
better.
UTP (Unshielded Twisted Pair)
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Most Common type
of cable installed in
buildings.
Most common media
for Ethernet and LAN
cabling.
Often used in
conjunction with
Telephone
distribution
Unshielded Twisted Pair
is smaller, more flexible,
and less expensive then
Shielded Twisted Pair.
UTP Cables
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A communications cable using one or
more pairs of wires that are twisted
together. When driven as a balanced line,
the twisting reduces the susceptibility to
external interference and the radiation of
signal energy.
Four Pair, 24 Gauge 100 Ohm copper
cable
 Unbalanced
 PVC or Plenum Jacket
 Types of UTP Cable: Category 3, 4,
5, and “Enhanced Category 5” or
Category 6
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Twist Pitch
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used in UTP cabling to identify the
different length distance of different pairs
within a single cable. The twist pitch
varies between pairs to reduce the affects
of NEXT or signals jumping from one pair
to another.
Category 3
Transmission Frequencies up to 16
MHz
 Intended for low speed data, telephone,
4 Mbs Token Ring, and 10 Mbs
Ethernet applications.
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Category 4
Transmission Frequencies up to 20 MHz
Suitable for all category 3 applications as well as 16
Mbs Token Ring
Category 5
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Transmission Frequencies up to 100 MHz
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Most popular for high speed applications
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Suitable for all Category 3 and 4 applications as
well as any copper based voice, video, or data
application such as: 100 Mbs "Fast Ethernet",
CDDI (FDDI over Copper), and possibly Gigabit
Ethernet over copper.
Enhanced Category 5
and Category 6
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High frequency applications such as Gigabit Ethernet
and certainly ATM will require better and higher
bandwidth cables than originally specified by the
Category 5 standard. While Gigabit Ethernet should be
compatible with Category 5 cabling, it is suggested that
cabling for high speed applications including Fast
Ethernet should exceed Category 5 standards.
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New standards are under development for such cabling,
however “enhanced Category 5” cabling is available
now.
UTP Installation
Considerations
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Unshielded Twisted Pair is smaller, more
flexible, and less expensive then Shielded
Twisted Pair.
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The Entire link or infrastructure (including
jacks and cross connect blocks) must be
composed of Category 5 components.
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All cables and components must be installed
and terminated properly to achieve Category
5 standards.
 Maximum distance of horizontal cabling is 295 feet (90
meters).
 Patch cords max length 6m
 Horizontal Cabling 90 m
 Equipment Cords 2 m
 Maximum pull tension for Category 5 UTP is 25 foot lbs.
(to avoid stretching the twists of the pairs).
 12" Minimum distance from florescent lighting
 5" Minimum distance between power and data cables.
 Minimum bend radius of 1 to 4 inches
 Cables must be dressed, labeled, and managed
 Cable ties must not be tightened (Velcro is better)
 No staples
 At termination points the jacket should be striped as little
as possible < 1/2 ".
Stranded UTP vs.. Solid UTP
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Stranded UTP
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usually used for patch cables
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wires or conductors are made of many
flexible strands in order to make the wire
stronger and more flexible.
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stranded UTP is not suitable for longer
distances due to its lower efficiency than
Solid UTP.
Solid UTP
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usually used in horizontal wiring (wiring to
jacks) in which the wires or conductors
are solid.
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Solid UTP cables are less flexible and
more brittle than stranded cables,
however they are cheaper and more
efficient.
TIA/EIA 568-A/B Modular
Plug Termination
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8 Pin Modular plugs
are used to
terminate UTP patch
cables.
Such cables are
identical on either
end (strait through)
Two “standards” are
available. 568A and
568 B.
TIA/EIA 568-A/B Modular
Jack Termination
Modular Jacks are used in patch
panels and wall jacks for termination
of UTP cables.
 Modular Jacks follow the 568A or
568B similar to Modular Plugs.
 All parts of a Category 5
implementation must be Category 5
certified for proper operation
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Optical Fiber
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Uses Light pulses to transmit data.
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Impervious to EMI (Electro-Magnetic
Interference) and RFI (Radio Frequency
Interference)
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Light looses signal strength much slower than
electricity which is good for distance.
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Fiber offers greater Bandwidth
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1 pair of fiber can offer greater bandwidth than
1,400 copper pairs in a voice system.
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Consists of a glass core surrounded by a
protective coating.
Multi-Mode and Single Mode
Fiber
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Multi-Mode fiber
 Uses LEDs to transmit data
 Offers a number of "paths" for light to traverse
or travel down a cable.
 Light travels down the core with a layer outside
of the glass core reflecting the signal back to
the core.
 The number of modes is determined by the
wavelength of the light source and the size of
the core.
 2Km max distance for multi-mode fiber.
Single Mode Fiber
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Single Mode Fiber
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Uses a laser to transmit data (rather than an
LED)
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More focused single path for light to travel
down.
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Used in long distance high bandwidth
applications