In-Depth Report on Fiber Optic Networks: History and Applications

This report provides a comprehensive overview of fiber optic networks, starting with their history and evolution from early light transmission experiments to modern communication infrastructure. It details the different types of fiber optics, including multi-mode and single-mode fibers, and discusses th...Read More

Fiber optic

Table of Contents
Introduction......................................................................................................................................1
History of fiber optic networks........................................................................................................1
Types of fiber optic / splicing machine and preparation for splicing/ encapsulation......................4
Types of fiber optic networks..........................................................................................................7
Hybrid networks / convert fiber optic networks into copper networks...........................................9
Data and Internet Protocol television / data centers / pop's / hub's................................................11
Testing and measuring / optical time domain reflectometer..........................................................14
Reviews..........................................................................................................................................15
References......................................................................................................................................17

Introduction
Fiber optic can be defined as the flexible and transparent fiber which is made up of the
plastic or a drawing glass. It is formed in a slightly thicker manner as compared to the human
hair. It is basically used for the long distance data networking which is highly performable in
nature. It is usually used in the telecommunications services such as telephones and television
along with the internet. It is considered as a technology which is basically used to transfer the
information in the form of pulses of light with the help of strands fiber (Floris, Adam, Calderón
and Sales, 2021). The following discussion is based on the fiber optic networks and its history.
Moreover, discussion is also based on the types of fiber optic and splicing machine and
preparation for splicing or encapsulation. The report also views the types of fiber optic networks
and hybrid networks and also the conversion of fiber optic networks into copper networks.
Furthermore, Data and Internet Protocol television and data centers or pop's and hub's, testing
and measuring or optical time domain reflectometer are also viewed in the below report.
History of fiber optic networks
Fiber optic networks is defined as the medium which helps in transmitting the
information. It uses the signals which is encoded onto the light in order to transfer the
information between the variety of nodes of the networks of telecommunications. They generally
operate from the limited or restricted range of local area networks or can be over the wide area
area networks. The biggest form of fiber optic network is the AT & T fiber. It is has the highest
coverage of 11.66 percent of the population in the US. The fiber optic networks which is ranked
as second is having the 11.11 percent coverage of the population in US. Its works while using the
cables in order to deliver the high speed of data in order to cover the large distances. The data
transfer is done using the cables at the speed of light (Lindsey and Martin, 2021).
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Fiber optic is a concept which is based on the light transmission. The conceptualization
of light transmission is introduced in the early 1840's at the time when French inventors named
Daniel Colladon and Jacques Babinet illustrated the guiding of light with the help of distances
through refraction. It was the time of ten years later in the middle of 1850's, one of the Irish
inventor named John Tyndall has conducted the similar type of illustration again with the help of
water fountains. These are considered as the early experiments which has resulted in the
introduction of the television at the time of the invention of the transmission of moving images
were illustrated at London in 1925 by one of the Scottish inventor named John Logie Baird.
Talking about of the year 1952, one of the UK based inventor named Narinder Singh Kapany has
invented the first and initial actor or real time fiber optic cable which is highly based on the
experiments of the inventor named John Tyndall which has made three decades earlier. Then in
1965 which is 13 years later, there were two British research scientist named Charles Kao and
George Hockman who has worked with standard telephones and cables which was discovered
using the attenuation of fiber optics which was the result of impurities in manufacturing. In 1965,
the very first working fiber optic data transmission system was illustrated by the German
inventor who was the physicist named Manfred Borner at Telefunken research laboratories in
Uim. In 1966, It was then followed by the first patent application for this particular technology.
NASA has used the fiber optics in the cameras of television which were sent to the moon in
1968. inventors were trying to lowering down the attenuation in a sufficient manner in which
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they theorised the concept of fiber optics which can then be used as a practical and real time
means of communication (Wang and Wolfbeis, 2019).
In the times of 1970, attenuation barrier was broken by the four scientist named Robert
Maurer and Donald Keck along with the Peter Schultz and Frank Zimar. There working corning
glass works at that time. After this type of actions, introduction of the advances of fiber optic
networks were done. Advances were made within the two decades. This is because the
researchers has tried to push the rate of attenuation as low enough for the fiber optics in order to
become the dominant carrier of the online and electronic transfer of information. In the times of
early 1990's, there was the growth of internet in a very high pace. This has resulted in
popularizing the use of fiber optic in order to wiring the whole world. This is done to provide the
basic technical infrastructure. This is basically done to encounter the perceived problems of the
Y2K issue. Now a days, there is a use of fiber optic networks in every nation of the world which
forms the absolute backbone of the modern communications infrastructure (Hui, 2019).
Fiber optics networks contains the light transmission with the help of long fiber rods
either of the glass or can be the plastics. The light which travels through this medium is with the
help of internal reflection. It is considered that the core medium of the cable or rod is much more
reflective as compared to the materials which is surrounding the core. This basically results in
the light to to keep being reflective back inside the core through which it can continue to travel
down the fiber. They are generally used in order to transmit the images and voice along with the
other data at the speed of light. These are much more capable of carrying the 65000 times more
data or information as compared to the copper wire. Such inventions has opened up the door to
the fiber optics networks for the process of commercialization. It has evolved from the long
distance telephone services to the wireless internet and also the medical devices as well such as
endoscope. Therefore, it is considered as the major part of the modern life (Lindsey, Rademacher
and Ajo‐Franklin, 2020).
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Types of fiber optic / splicing machine and preparation for splicing/
encapsulation
There are majorly two primary types of fiber optics. Multi mode fiber is one of the type
of fiber optic. It is known as the multi mode because it carries more than one light rays or modes
and at the same time it also consist the varieties of optical properties at the core. It provides the
concept of light travelling from the shortest path or down the middle which travels the slowest. It
has the larger core which simplifies the connections and also take the advantages of the less cost
VCSEL and LED technologies that has the operations in the 850nm window. Because of the
dispersion, it has the limited range and therefore it has the tendency to use the premises cabling
at less than a kilometre. It basically comes in two fundamental sizes that are 62.5 and 50
microns. Single mode fiber is an another type of the fiber optic. It is known as the single mode
because it carries one light ray or mode. As compared to the multi mode, single mode has much
more smaller core size of 9 microns. It consist of the single path of light which can travel much
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more longer distances up to 100 km. This type of fiber optic highly requires the costly
electronics which can operate in the 1310 and 1550nm windows. It is typically used in longer
distances using local area networks and cable TV along with the telephony applications (Zhao,
Hu, Hu and Peng, 2020).
There are certain fiber optic cable transmission distances which are based on the industry
standards. These are the minimum distances achieved with each of the fiber type. Therefore,
some of the cable manufacturers offers the improved cables which exceeds this. There are some
of the distances which are only for the ratified standards. It is important to check the
manufacturer specifications. Multi mode type has different other types such as OM1, OM2,
OM3, OM4 and OM5. OM1 has 62.5 / 125 core / cladding in um. It has fast Ethernet 100 mb of
2 km. It further has gigabit GbE of 275m. Moreover, 10 Gigabit 10 GbE of 33m. Talking about
OM's they have 50 / 125 of core / cladding in um and 2 km of fast Ethernet 100mb. Single mode
has OS1 and OS2 types. It has 9 / 125 of core / cladding in um and 40 km of fast Ethernet
100mb. There are some of the exceptions to all such discussed distances. Such as gigabit
transmission distance can be extended for all the types of multi mode fiber cable up to 2 km
with the help of proprietary gigabit extenders. It can be useful when there is an existing
installation of the fibre cabling and also when there is an additional performance required. Range
of OM1 fibre optic cable can be increased up to 550m with the help of a mode conditioning cable
and a single mode modules (Pevec and Donlagić, 2019).
There are basically two types of splicing machines. Mechanical splicing is one of the type
of splicing machine. It is the type which do not fuse two optical fibres together in a physical
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form. But instead, two fibres are held in the form of butt to butt inside a sleeve with the help of
some mechanical mechanism. It results in the worse insertion losses and back reflection as
compared to the second type. This is the type which is mostly used for the repairs which are in
the emergency and also for the fibre testing as well. Fusion splicing is an another type of splicing
machine. In this type, two fibres are fused or welded together with the help of the electric arc. It
is considered as the most broadly used method of this type. This is because it renders the lower
insertion loses as compared to the mechanical splicing and also the no back reflection in a
virtual manner. Moreover, it also renders the most reliable joint among the two fibres. It has the
process which is done by the automatic machine which is known as the fusion splicer or fusion
splicing machines (Du, Dutta, Kurup and Wang, 2020). There are certain steps for fusion
splicing using the splicing machine. First step is to put the fusion splice protection sleeve.
Second step is to strip the fibre which means stripping back all the coatings of fibre down to the
125um bare fibre and cleaning the bare fibre using 99% isopropyl alcohol. Third step is to
cleaving the fibre using the high precision cleaver. Quality of the splice is based on the cleave
quality that is why it is considered as the most important step. Fourth step is to put the fibre into
the holders of the fibres in the fusion splicer. Then pressing the start button in order to start the
fusion splicing. Fifth step is to heat and shrink the protection sleeve in order to protect the
splicing joint (Bai, Li, Barreiros and Shepherd, 2020).
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Types of fiber optic networks
There are several types of fiber optic networks and such classifications is based on the
three major points that are the refractive index and materials used along with the mode of
propagation of light. Type of fibre optics which is based on the refractive index classification are
the majorly of two types such as step index fibers and graded index fibers. Step index fibres is
one of the type of refractive index in fiber optic. It is the type which mainly contains the core that
is surrounded by the cladding. It basically has the single uniform index of refraction. Graded
index fibres is an another type of refractive index in fiber optic. It is the type in which there is a
decrement of optical fibre refractive index because of the increment of the radial distance from
the fiber axis (Keiser, 2021). Type of fibre optics which is based on the materials used
classification are the majorly of two types such as plastic optical fibers and glass fibers. Plastic
optical fibers is one of the type of materials used in fiber optic. It is the type in which the
transmission of light is performed with the help of some core materials named as
polymethylmethacrylate. Glass fibers is an another type of materials used in fiber optic. It is the
type in which it highly contains the fine glass fibers in an extreme manner. Type of fibre optics
which is based on the mode of propagation of light classification are the majorly of two types
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such as single mode fibers and multi mode fibers. Single mode fibers is one of the type of mode
of propagation of light in fiber optic. It is the type in which it is used for the transmission of
signals for a long distances on a single path. Multi mode fibers is an another type of mode of
propagation of light in fiber optic. It is the type in which it is used for the transmission of signals
for a short distances on more than one path (Bao, Huang, Hoehler and Chen, 2019).
There are four combination types of optic fibers in which the mode of propagation of
light and the refractive index is used for the combination as a core. Step index single mode fibers
is one of the type of this combination. It is the combination of step index fibers and single mode
fibers. Graded index single mode fibers is an another type of this combination. It is the
combination of graded index fibers and single mode fibers. Step index multi mode fibers is also
one of the type of this combination. It is the combination of step index fibers and multi mode
fibers. Graded index multi mode fibers is also an another type of this combination. It is the
combination of graded index fibers and multi mode fibers (Zhou and Jokerst, 2020). Fiber optic
networks work on the principle of total internal reflection. It uses the rays of light in order to
transfer the large amount of data. But there is an issue that the rays of light travels only in a
straight line. Therefore, it is important to have the long straight wire with no bends in order to
make it work. This cannot be possible as it creates problems while implementing and using of it.
So thereby optical cables are designed in order to fulfil the purpose of it. Such cables bends all
the rays of light in an inward manner with the help of TIR. Such installation of cables has helped
in the travel of rays of light in a continuous manner which bounces off the optical fiber walls
which further supports in transmitting the end to end information. Fiber optic has the relay
system which mainly contains of some of the components. Such as the transmitter is one of the
component. It is responsible for producing the light signals and also encodes them so that they
can get fitted for transmission. The optical fiber is an another component. It is responsible for
providing the medium in order to transmit the signal or light pulse. The optical receiver is also
one of the component. It is responsible for receiving the transmitted signal or light pulse and also
decodes them so that it can get fitted to be used. The optical regenerator is also an another
component. It is responsible for the long distance transmissions (Zhang, Fang, Stefani and Tan,
2020). It has several advantages such as it economical and cost effective in nature. It has the
positive feature that it is thin and non flammable. It consume less power and also has the less
signal degradation. Moreover, it is flexible and lightweight in nature.
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Hybrid networks / convert fiber optic networks into copper networks
Fiber optic hybrid networks is also known as the hybrid fiber coaxial which is an access
network management. It is the kind of technology which is specified under the domain of
telecommunications technology in which the fiber cables and coaxial cables are widely used. It is
used in the several portions of the network in order to carry the data and all its content. Format of
the data are such that the video and music along with the voice and recordings and many more.
There is a formation of hybrid fiber coaxial access network manager in order to support the
assorted types functions which are associated with the management and operations of the hybrid
coaxial fiber access plant. It facilitates the monitoring of the upstream and downstream paths of
transmission which supports the faults sectionalization. There are basically two kinds of
modulations or technologies used for the cable modem transportation such as QPSK technology
and QAM technology. QPSK stands for the quadrature phase shift keying. It is responsible for
modulating the two bits at once while selecting one out of four carrier phase shifts which has
high possibility such as 0, 90, 180 or 270 degrees. It facilitates with the signal which carries two
times the information as compared to the normal PSK with the help of same bandwidth. QAM
stands for quadrature amplitude modulation. It is the digital television standard and a format
through which the encoding is done of the digital cable channels and also then transmitted
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through cable television renders. It is generally used in the several communication systems for
example dial up modems and Wi-Fi (Zheng, Zhu, Xiao and Deng, 2020).
There are basically three techniques of monitoring the hybrid fiber coaxial system.
Monitoring bit error rate is one of the technique. It is calculated by simply dividing the received
quantity of bits in error by the bits transmitted which is total in number with the same time
duration. Frame error rate is an another technique. It is used to identify the number of frames
used in order to test before resulting out either pass or fail. It sets the percent of frame errors
from the range between 0.1% to 30%. Carrier to noise ratio is also an another technique. It is
considered as a measure of the carrier strength received which is related to the strength of the
noise which is received. It renders good quality of reception and high accuracy and reliability in
communications (Esfahani Monfared, 2020). There are various advantages of hybrid fiber
coaxial. Such as it facilitates with the high quality performance in cost efficient method. It make
sure that no one is changing the existing using networks as it helps with the separate connection.
It supports the high frequency bandwidth and is more responsible to any outside disruption or
noise in an efficient and highly immune manner. There are various disadvantages of hybrid fiber
coaxial. Such as it can get damages due to the lightning in the network area. It has only restricted
node connections which cannot be increased even after changing its process of installation.
Installation in the local environment has a huge cost and can also raise the overall budget as well
(Liu, Li, Zhang and Zhao, 2021).
Copper networks is referred to the copper based telephone wiring which are majorly used
in homes and also via wireline phone lines. There are DSL networks such as ADSL and VDSL
along with the xDSL are also relied on the copper networks. Such networks are formulated using
bulky copper wires which uses electrons for data transmissions. Fiber optic to copper converters
helps in connecting of the copper based Ethernet equipment over the link of fiber optic. This
facilitates the extension of the links over large distances using the fiber optic cable which
safeguards information from any noises and also from any interferences. It future proofs the
network along with the additional capacity of bandwidth (Gong, Xiang, OuYang and Chan,
2019).
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Data and Internet Protocol television / data centers / pop's / hub's
Internet Protocol Television is defined as the content of television which is delivered over
the protocol of internet networks. It is done with contrasting to the delivery via traditional
terrestrial and satellite along with the cable television formats. It only helps in displaying the
downloaded media but also has the ability to stream the source media continuously. It provides
the service in terms of television programming and also the other content of the video with the
help of transmission control protocol or internet protocol suite instead of broadcast TV and cable
TV along with the satellite signals. Internet protocol television is used because it has the ability
to collaborate and integrate TV with other internet protocol based services such as high speed
internet access and VOIP (Kumari, Samiappan, Kumar and Sudhakar, 2019). There is another
type is the switched internet protocol network which facilitates the delivery of the content and
functions in a more efficient manner. Internet protocol TV works while using the internet
protocol which is considered as the transport protocol. It is a delivery mechanism which delivers
videos to the users. It works when the user clicks on any TV program, it means they are
requesting for the video. Then the requested video is divided from assorted servers or sources
into the data packets and the it is sent over the internet. It provides both types of content that are
the live videos and pre recorded videos as well along with the audio over IPTV (Martin, Lindsey,
Ajo‐Franklin and Biondi, 2021).
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Data centers can be defined as the buildings or a group of buildings which is used to
house the computer systems and related components as well. Such as storage systems and
telecommunications systems. Data centeres are important because it has several uses to
businesses and also for the personal use as well. Such as it supports and facilitates with the
emails and file sharing along with the productivity applications also. It also assist in the customer
relationship management and enterprise resource planning and databases. It also aids in big data
management and uses artificial intelligence along with the machine learning. It makes use of the
virtual desktops and provides collaboration and communication services as well. There are three
basic core components of data centers such as network infrastructure and storage infrastructure
and also the computing resources. Network infrastructure connects servers of both the types that
are virtualised or physical and data center services along with the storage and external
connectivity to the end user locations. Storage infrastructure stores the data which is considered
as the fuel of the modern data center therefore such storage systems is basically used to hold this
type of valuable commodity. Computing resources provides applications which are considered as
the engines of data centers (Spica, Perton, Martin and Biondi, 2020). These are the servers which
renders processing and memory along with the local storage and network connectivity which
fosters the applications. Data centers operates using the appliances of network security and
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application delivery assurances as well. Appliances includes the firewall and intrusion protection
in order to protect the data center. Application performance is being maintained because such
mechanism renders the resiliency and availability of applications through automatic failover and
load balancing. There are various components of data center which need essential infrastructure
in order to support the hardware and software of the center. All such includes the power
subsystems and uninterruptible power supplies along with the ventilation and cooling systems
which is followed by the fire suppression and backup generators and also the connections to
external networks. There are certain standards of data center infrastructure such as ANSI/TIA-
942 is one of the widely adopted data center design. It makes sure the compliance using four
level of tiers that rated for the fault tolerance and redundancy. Tier 1 is based on the basic site
infrastructure which offers limited protection against any physical events. Tier 2 is based on the
redundant capacity component site infrastructure which offers enhanced protection against
physical events. Tier 3 is based on the concurrently maintainable site infrastructure which offers
protection against all virtual physical events. Tier 4 is based on the fault tolerant site
infrastructure which offer highest level of fault tolerance and redundancy (Amiri and Rashed,
2019). There are several types of data centers such as enterprise data centers and manages
services data centers along with the colocation data centers and cloud data centers.
Testing and measuring / optical time domain reflectometer
Optical time domain reflectometer can be defined as the optoelectronic instrument which
is used to feature the optical fiber. It is an instrument which is used to analyse and detect the
back reflected and scattered light with the help of an optical fiber because of the imperfections
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and impurities in the fiber. OTDR has the operating principle which is similar to that of the radar
because it performs the measurement of time of the reflected light. It basically consist the
characteristic of an optical fiber cable with the help of the propagation is done of the optical
signal (Shi, Tian and Gervais, 2020).
OTDL is an instrument which is used to assess and evaluate the several parameters such
as reflectance angle of the light signal and fiber attenuation and also the splice losses. It works
when the signal is transferred with the help of an optical fiber cable, then at the time of
transmission, some of the parts of the signal gets reflected. This is the reflection which leads to
the signal attenuation which majorly occurs because of the defects of the fiber cable. Therefore,
OTDR is an instrument which is used as the testing instrument in the optical fibre
communication systems so that the determination of the signal loss level inside the fiber cable
can be done. OTDR is a device which is generally used to detect the faults in the link of optical
fiber of the communication network. It has several functions which includes the transmission and
generation of the high speed series optical pulses in the fiber. This is a device which is equivalent
to the electronic time domain reflectometer which injects the series of optical pulses in the fiber
under testing methods and extracts the same from the end of the fiber. OTDR generally sends the
short light pulses in the fiber. Occurrence of light which scatters in the fiber is because of the
discontinuities like connectors and splices along with the bends ans faults. After this, OTDR then
detects the backscattered signals along with the analysis of it. The strength of the signals is
measures for the particular intervals of time durations which is used to feature the events
(Davydov, Antonov and Angelina, 2019).
OTDR has several steps to run. For example, turning on the OTDR and allowing the time
in order to get warm up is the first step. Cleaning of the connectors and the mating adaptors is the
second step. Attaching the launching cable to OTDR and then attaching the receiving cable to far
end of the cable is the third step. Setting up the parameters of testing is the fourth step. Attaching
cable to the end of the test of the launching cable and then attaching the receiving cable to far
end of the cable is the fifth step. Then finally acquiring the trace is the sixth step for running the
OTDR. It is an assumption that the typical fiber attenuation is of approximately 0.20 db/km at
1550 nm. It is the splices of every 2 km in a loss of 0.1 db per splice. OTDR displays and
controls encompasses of the tasks options which contains range and pulse width along with the
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wavelength and measuring mode which is followed by the backscatter coefficient and index of
refraction (Mowbray and Amiri, 2019).
There is an optical detector which is used in the OTDR that is the semiconductor
photodiodes. It is the most commonly used detectors in the optical fiber systems because they
supports with the good performances which are compatible with the optical fibers which are
being small in size and also they are relatively of low cost as well. OTDR are simply and easily
available for the measurements through the whole wavelength range. Instruments of OTDR can
be used to perform the tests for both the single and for the dual wavelengths but for the single
mode and also for the multi mode optical fiber links. It majorly used for measuring the optical
losses and dispersion measurements also. It is also having the disadvantage such as the dead zone
can occur at the time of measuring the defects (Lefevre, 2022).
Reviews
It is reviewed that fiber optic is an important concept to learn and study so that its
applications can be applied in the real world organizations. This is because it helps in the internet
connection which connects the entire world in order to have the better communication flow
either for the commercial purposes or for personal use as well. The reason being is that it has
major and essential applications in different industries. Such as world wide web and computer
networking along with the surgery and dentistry which is followed by the automotive industry
and telephone and also the lighting and decorations. Moreover, mechanical inspections and cable
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television or military and space applications. It uses the light as a medium for secure and fast
transmission. Therefore, it is important to analyse the history of fiber optic networks. It is
essential to examine the types of fiber optic and splicing machine and its preparation. It is
necessary to determine the types of fiber optic networks. It is significant to assess the hybrid
networks and conversion of fiber optic networks into copper networks. It is crucial to evaluate
the data and Internet Protocol television and data centers or pop's and hub's. It is vital to
investigate about the testing and measuring or optical time domain reflectometer. Hence, the
above discussion covers all such areas in order to better understand the conception of fibre optic.
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References
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Bao, Y., Huang, Y., Hoehler, M.S. and Chen, G., 2019. Review of fiber optic sensors for
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Davydov, R., Antonov, V. and Angelina, M., 2019, October. Parameter control system for a
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Spica, Z.J., Perton, M., Martin, E.R. and Biondi, B., 2020. Urban seismic site characterization by
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Wang, X.D. and Wolfbeis, O.S., 2019. Fiber-optic chemical sensors and biosensors (2015–
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Zhang, Z., Fang, Z., Stefani, J. and Tan, Y., 2020. Modeling of fiber-optic strain responses to
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