Network cables

This document covers the basics of Network cables which are used in the site.

1. Network Cables

Network Cable:
Network cable acts like a medium through which information travels from one network device to the other.
The type of cable selected for a network depends on the network’s size, topology, and procedure.

Types of Network Cabling:
1. Copper cabling.
2. Fiber-optic cabling.

Copper cabling:
Copper cabling is the most common type of cabling used in networks today.
Networks use copper media because it is inexpensive, easy to install, and has low resistance to electrical current.
However, copper media is limited by distance and signal interference.
Data is transmitted on copper cables as electrical pulses. A detector in the network interface of a destination device
must receive a signal that can be successfully decoded to match the signal sent. However, the farther the signal travels,
the more it deteriorates. This is referred to as signal attenuation.

Fiber-optic cabling:
Fiber-optic cabling is the other type of cabling used in networks. Because it is expensive, it is not as commonly used at
the various types of copper cabling. But Fiber-optic cabling has certain properties that make it the best option in certain
situations.
Optical Fiber cable transmits data over longer distances and at higher bandwidths than any other networking media.
Data is transmitted on fiber-optic cables in the form of light. Unlike copper wires, they can transmit signals with less
attenuation and is completely immune to EMI and RFI. Optical fiber is commonly used to interconnect network devices.

Interferences in Copper cables and their solutions
Interferences:
• Electromagnetic interference (EMI)
• Cross talk
Solutions:
• To counter the negative effects of EMI and RFI, some types of copper cables are wrapped in metallic shielding
and require proper grounding connections.
• To counter the negative effects of crosstalk, some types of copper cables have opposing circuit wire pairs
twisted together, which effectively cancels the crosstalk.
============================

2. Types of Copper Cabling
There are three main types of copper media used in networking.
1. Unshielded Twisted-Pair (UTP) cable.
2. Shielded Twisted-Pair (STP) cable.
3. Coaxial cable.

Unshielded Twisted-Pair (UTP) cable:
Unshielded twisted-pair (UTP) cabling is the most common networking media. UTP cabling, terminated with RJ-45
connectors, is used for interconnecting network hosts with intermediary networking devices, such as switches and
routers.
In LANs, UTP cable consists of four pairs of color-coded wires that have been twisted together and then encased in a
flexible plastic sheath that protects from minor physical damage.

1. The outer jacket protects the copper wires from physical damage.
2. Twisted-pairs protect the signal from interference.
3. Color-coded plastic insulation electrically isolates wires from each other and identifies each pair.

Shielded Twisted-Pair (STP) cable:
Shielded twisted-pair (STP) provides better noise protection than UTP cabling. However, compared to UTP cable, STP
cable is significantly more expensive and difficult to install. Like UTP cable, STP uses an RJ-45 connector.
STP cables combine the techniques of shielding to counter EMI and RFI, and wire twisting to counter crosstalk. If the
cable is improperly grounded, the shield may act as an antenna and pick up unwanted signals.

1. Outer jacket.
2. Braided shield.

3. 3. Foil shields.
4. Twisted pairs.

Coaxial cable:
Coaxial cable consists of the following:
• A copper conductor is used to transmit the electronic signals.
• A layer of flexible plastic insulation surrounds a copper conductor.
• The insulating material acts as a shield for the inner conductor.
• The entire cable is covered with a cable jacket to prevent minor physical damage.
Although UTP cable has essentially replaced coaxial cable in modern Ethernet installations, the coaxial cable design is
used in the following situations:
Wireless installations - Coaxial cables attach antennas to wireless devices. The coaxial cable carries radio frequency (RF)
energy between the antennas and the radio equipment.
Cable internet installations - Cable service providers provide internet connectivity to their customers by replacing
portions of the coaxial cable and supporting amplification elements with fiber-optic cable. However, the wiring inside
the customer's premises is still coax cable.


1. Outer jacket
2. Braided copper shielding
3. Plastic insulation
4. Copper conductor
==========================

4. UTP Cabling
UTP cable does not use shielding to counter the effects of EMI and RFI. Instead, cable designers have discovered other
ways that they can limit the negative effect of crosstalk:
Cancellation - Designers now pair wires in a circuit. When two wires in an electrical circuit are placed close together,
their magnetic fields are the exact opposite of each other. Therefore, the two magnetic fields cancel each other and also
cancel out any outside EMI and RFI signals.
Varying the number of twists per wire pair - To further enhance the cancellation effect of paired circuit wires, designers
vary the number of twists of each wire pair in a cable.

UTP Cabling Standards and Connectors:
UTP cabling conforms to the standards established jointly by the TIA/EIA. Cables are placed into categories based on
their ability to carry higher bandwidth rates.
The categories of UTP cable are as follows,
• Category 3 was originally used for voice communication over voice lines, but later used for data transmission.
• Category 5 and 5e is used for data transmission. Category 5 supports 100Mbps and Category 5e supports 1000
Mbps.
• Category 6 has an added separator between each wire pair to support higher speeds. Category 6 supports up to
10 Gbps.
• Category 7 also supports 10 Gbps.
• Category 8 supports 40 Gbps.
UTP cable is usually terminated with an RJ-45 connector.

5. RJ-45 UTP Plugs & Sockets:



UTP cable Types and Applications:

Cable Type
‘
Standard

Application
Straight-through Both ends T568A or T568B Connects a network host to a network device such as a switch or hub
Cross-over One end T568A, other end
T568B
Connects two network hosts Connects two network intermediary
devices (switch to switch or router to router)
Rollover Cisco proprietary Connects a workstation serial port to a router console port, using an
adapter


==========================

6. Types of UTP cables with Shielded, Unshielded
and Foiled Scenarios
The Types of UTP cables with Shielded, Unshielded and Foiled Scenarios are as follows,
1. F/UTP: Foiled with Unshielded Twisted Pairs.
2. S/UTP: Shielded with Unshielded Twisted Pairs.
3. SF/UTP: Shielded and Foiled with Unshielded Twisted Pairs.
4. U/FTP: Unshielded with Foiled Twisted Pairs.
5. F/FTP: Foiled with Foiled Twisted Pairs.
6. S/FTP: Shielded with Foiled Twisted Pairs.
7. SF/FTP: Shielded and Foiled with Foiled Twisted Pairs.

F/UTP: Foiled with Unshielded Twisted Pairs:
This type of cable features an overall foil shield wrapped around unshielded twisted pairs and a drain wire. When the
drain wire is correctly connected, unwanted noise is redirected to ground, offering extra protection against EMI/RFI.

S/UTP: Shielded with Unshielded Twisted Pairs:
This cable construction has an overall braid screen with unshielded twisted pairs. The cable is capable of supporting
higher transmission rates across longer distances than UTP and provides better mechanical strength and grounding due
to the braid.

SF/UTP: Shielded and Foiled with Unshielded Twisted Pairs:
This cable has both an overall braid shield and foil shield with unshielded twisted pairs. This cable offers effective
protection from EMI both from the cable and into the cable as well as much better grounding due to the additional
braid.

7. U/FTP: Unshielded with Foiled Twisted Pairs:
This type of cable has no overall shielding but the individual twisted pairs are wrapped in a foil screen, offering some
protection from EMI and crosstalk from adjacent pairs and other cables.

F/FTP: Foiled with Foiled Twisted Pairs:
This type of cable features an overall foil shield with individually foil tape shielded twisted pairs. The cable construction
is designed to provide the assembly with greater protection from crosstalk from adjacent pairs and other cables, RFI and
EMI.

S/FTP: Shielded with Foiled Twisted Pairs:
The individual twisted pairs are wrapped in a foil tape before being wrapped in an overall flexible yet mechanically
strong braid screen. The additional foil on the twisted pairs helps to reduce crosstalk from adjacent pairs and other
cables. The braid provides better grounding.

SF/FTP: Shielded and Foiled with Foiled Twisted Pairs:
Offering the maximum protection from RFI/EMI, crosstalk and alien crosstalk, this cable has both an overall braid shield
and foil shield, with individually foil tape screened twisted pairs. This type of cable provides the best level of protection
from interference and better grounding due to the braid.

8. ===================================


Comparison between different types of Copper Cabling

Common Industry
Acronyms
ISO/IEC11801 Name Cable Shielding Type Twisted Pair Shielding Type

1

UTP

U/UTP

None

None

2

FTP, STP, ScTP

F/UTP

Foil

None

3

STP, ScTP

S/UTP

Braiding

None

4

SFTP, S-FTP, STP

SF/UTP

Braiding & foil

None

5

STP, ScTP, PiMF

U/FTP

None

Foil

6

FFTP

F/FTP

Foil

Foil

7

SSTP, SFTP, STP, PiMF

S/FTP

Braiding

Foil

8

SSTP, SFTP

SF/FTP

Braiding & foil

Foil


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9. Types of Fiber-Optic Cabling
Fiber-optic cables are classified into two types.
1. Single-mode fiber (SMF).
2. Multi-mode fiber (MMF).
Note: Cladding is 10 times thicker than the core & Micron is one-millionth of a metre.
Single-mode fiber (SMF):
SMF consists of a very small core and uses expensive laser technology to send a single ray of light. SMF is popular in
long-distance situations spanning hundreds of kilometers, such as those required in long haul telephony and cable TV
applications.

Multi-mode fiber (MMF):
MMF consists of a larger core and uses LED emitters to send light pulses. The light from an LED enters the multimode
fiber at different angles. It is popular in LANs because they can be powered by low-cost LEDs. It provides bandwidth up
to 10 Gbps over link lengths of up to 550 meters.

10. Difference between SMF and MMF:

Single-mode fiber (SMF)

Multi-mode fiber (MMF)
• LASER.
• For long distances.
• 9 microns ➔ 100 km @ 100 Mbps.
• Cable is bit cheaper but costly modules.
• Made up of glass only.
• LED.
• For short distances.
• 50 microns ➔ 2 km @ 100 Mbps
• Cable is expensive but cheaper modules.
• Made up of glass/plastic.

Fiber-optic Cable usage
• Enterprise Networks - Used for backbone cabling applications and interconnecting infrastructure devices.
• Fiber-to-the-Home (FTTH) - Used to provide always-on broadband services to homes and small businesses.
• Long-Haul Networks - Used by service providers to connect countries and cities.
• Submarine Cable Networks - Used to provide reliable high-speed, high-capacity solutions capable of surviving in
harsh undersea environments at up to oceanic distances.

Fiber-optic Connectors
The main differences among the types of connectors are dimensions and methods of coupling. Businesses decide on the
types of connectors that will be used, based on their equipment.
1. Straight-Tip (ST) Connector.
2. Subscriber Connector (SC) Connector.
3. Lucent Connector (LC) Connector.
4. Fixed Connector (FC) Connector.

11. ST connector
A straight tip connector (ST connector) is a connector used in fiber-optic cables that utilizes a bayonet-style plug and
socket. It has become the standard for commercial wirings. The ST connector setup allows for unidirectional
communication, so two ST connectors and two fiber cables are used for bidirectional communication. It is most common
in network environments such as campuses, corporate networks and in military applications where the quick connecting
bayonet had its advantages at the time.
SC connector
SC (Subscriber Connector) stands for subscriber connector and is a standard-duplex fiber-optic connector with a square
molded plastic body and push-pull locking features. SC connectors are typically used in data communication, CATV, and
telephony environments.
LC Connector
LC (Lucent Connector) is a small form factor connector that uses a 1.25 mm ferrule, half the size of the SC. Good
performance, highly favored for singlemode. With the introduction of LC compatible transceivers and active networking
components, its steady growth in the FTTH arena is likely to continue.
FC Connector
The FC (Fixed connector) is a fiber-optic connector with a threaded body, which was designed for use in high-vibration
environments. It is commonly used with both single-mode optical fiber and polarization-maintaining optical fiber.

Fiber Patch Cords & Drop Cords
Fiber patch cords are required for interconnecting infrastructure devices. The use of color distinguishes between single-
mode and multimode patch cords. A yellow jacket is for single-mode fiber cables and orange for multimode fiber cables.

12. A fiber-optic patch cord is a fiber-optic cable capped at either end with connectors that allow it to be rapidly and
conveniently connected to an optical switch or other telecommunication equipment.
The main difference between patch cords and drop cords is that Fiber drop cords are located on the subscriber end to
connect the terminal of a distribution cable to a subscriber's premises.


Construction-wise types of Fiber-optic cables

In-door OFC

Out-door / Direct burial OFC

13. Optical Fiber Distribution Frames (OFDF)

Wall mounted OFDF

Rack mounted OFDF





Laying of OFC
The fiber-optic cable will be laid in a purpose-built trench, manhole, and presented by route markers.


Splicing
The technique to connect two optical fiber cables is called splicing.

14. There are two types of splicing.
1. Fusion Splicing.
2. Mechanical Splicing.


Optical fiber Link loss and Length Calculations

15. SONET & SDH
• SONET (Synchronous Optical Networking).
• SDH (Synchronous Digital Hierarchy).
These are the Standardized protocols that transfer multiple digital bit streams over optical fiber using lasers or highly
coherent light from LEDs

SONET is used in USA / Canada & SDH is used Worldwide

16. Fiber to the X (FTTx)
• FTTN / FTTLA (Fiber-to-the-node, -neighborhood, or -last-amplifier):
Fiber is terminated in a street cabinet, possibly miles away from the customer premises, with the final
connections being copper.

• FTTC / FTTK (Fiber-to-the-curb, -closet, or -cabinet):
This is very similar to FTTN, but the street cabinet or pole is closer to the user's premises, typically within 1,000
feet (300 m).

• FTTP (Fiber-to-the-premises):
This term is used either as a blanket term for both FTTH and FTTB, or where the fiber network includes both
homes and small businesses.
1. FTTB (Fiber-to-the-building). 2. FTTH (Fiber-to-the-home).

• FTTD (Fiber-to-the-desktop):
Fiber connection is installed from the main computer room to a terminal near the user's desk.

• FTTE / FTTZ (Fiber-to-the-telecom-enclosure or fiber-to-the-zone):
It is a form of structured cabling typically used in enterprise LAN, where fiber is used to link the main computer
equipment room to an enclosure close to the desk or workstation.
============================
UTP and Fiber-optic Cabling Comparison


Implementation Issues

UTP Cabling

Fiber-optic Cabling

Bandwidth supported

10 Mb/s - 10 Gb/s

10 Mb/s - 100 Gb/s

Distance

Relatively short (1 - 100 meters)

Relatively long ( 1 - 100,000 meters)

Immunity to EMI and RFI

Low

High (Completely immune)

Immunity to electrical
hazards

Low

High (Completely immune)

Media and connector costs

Lowest

Highest

Installation skills required

Lowest

Highest

Safety precautions

Lowest

Highest

17. I/O Jack & Face Plate

I/O Jack
The I/O ports and connectors on the back panel of the system are the gateways through which the system
communicates with external devices.

19. Server Racks & Network Racks

Server Racks
The primary use of server racks is to accommodate server-related equipment. To put it simply, a server rack is used to
house a server computer which might contain equipment like UPS ES, PSU, monitors, Media Storage Drives,
Motherboard, CPU, Memory and so on.
The most common server racks come with 36 inches depth and 24 inches height. Aside from that, these server racks
come in different types, shapes, and sizes. For instance, we might see a server rack which can be mounted on the wall.
In contrast, there might be another which is portable and can only be placed on the floor.
Most of the server racks are designed keeping some key factors in mind like air flow, the safety of the pieces of
equipment. So, most popular server racks come with secure doors and perforated side panels and front/rear.



Network Racks
A network rack is used to house networking related equipment like routers, network cables, switches, patch panels, and
other accessories. These network racks are very narrow in size. Usually, the depth of network racks won’t be higher
than 31 inches. They do come with doors and side panels in most cases. But they don’t have perforated doors. Also, they
are designed in a way so that it can be perfect for managing all the network cables easily.

20. Difference between server rack and network rack
1. The Depth
In terms of height, a server rack can be similar to a network rack. But, in terms of depth, there can be
dissimilarities. For instance, a server rack needs to contain bigger and larger equipment compared to a network
rack. So, a server rack must have more depth than a network rack. Therefore, a server rack will take a bit more
space than a network rack.


2. The Design
Server racks will almost always have doors and side panels. Some of them can be locked from outside for further
security. And, the front door and the rear panel might come with plenty of holes to allow required ventilation.
But the network racks don’t have perforated doors usually. They come with tempered glass or polycarbonate
doors. And most of the network racks don’t have any side panels.

3. Cable Management
A server computer might not come with a lot of cables. Thus, it can be quite compact and also hard to do cable
management in it. However, as it is likely that a network rack will have to contain a hefty number of cables, it
will have plenty of features for easy and fast cable management. That way, we will be able to keep all of your
cables organized.



4. The Air Flow System
As we know that network devices don’t produce a lot of heat. On the other hand, a server might generate a
huge amount of heat. It is always a good idea to keep the heat under control to run the servers at its best
capacity. As a result, we will find various ventilation system on a server rack such as perforated door, movable
side panels, and so on.

21. High-density Polyethylene pipes (HDPE)

Polyethylene has become the most popular material of pipe distribution systems as it offers significant benefits
compared to alternative materials.

Following are the most important features of HDPE Pipes:
• High flexibility. Can be bent as much as 25-40 times of the pipe diameters, thus reducing unnecessary pipe joints
• Light weight with only 0.95 grams/cm 2. Weigh only 1/5 of steel pipes of the same size
• Rust proof and high resistance to damaged chemicals, making the product last up to 50 years
• Super smooth internal surface, reducing the chance of pipe blockage.

Benefits of HDPE
1. Heat Fused Joints
HDPE pipe can be heat fused together to form a joint that is as strong as or stronger than the pipe itself and is
leak free.

2. Flexible and Fatigue Resistant
HDPE pipe can be bent to a radius 25 times the nominal pipe diameter. This can eliminate many fittings required
for directional changes in a piping system where fittings are required with alternate materials.

3. Construction Advantages
Polyethylene is about one-eighth the density of steel, it does not require the use of heavy lifting equipment for
installation.

4. Cost effective and Long-term Usage
Polyethylene pipe installations are cost effective and have long term cost advantages due to its physical
properties, leak free joints and reduced maintenance costs.

5. Corrosion and Chemical Resistant
HDPE pipe has superb chemical resistance and is the material of choice in harsh chemical environments.

6. Handling
It is much easier to handle and install HDPE pipe vs. the heavier metallic or concrete pipe segments.

22. Face Plate
Networking faceplates are plastic or metal plates used for Cat5, Cat5e or Cat6 ethernet cable installation. They organize
and keep network cables out of reach, so are ideal for use in residential or commercial settings. They are also known as
wallplates or outlet covers.



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