Understanding Networks and Their Evolution

The assignment is a comprehensive guide to understanding networks and their evolution. It starts with a brief introduction to what a network is and takes the reader on a journey through the history of communication and information sharing, from Stone Age languages to modern internet. The assignment covers basic network components like cables, switches, and hubs, as well as different network architectures such as client-server and peer-to-peer. It also introduces various network topologies including bus, ring, mesh, and star. Finally, it provides an overview of local area networks (LANs), metropolitan area networks (MANs), and wide area networks (WANs). The assignment aims to provide a thorough understanding of networks and their evolution, making it a valuable resource for students and professionals alike.

Contents
1. Executive summary (Part-01)................................................................................................3
2. Introduction............................................................................................................................3
3. Introduction to network..........................................................................................................3
LAN........................................................................................................................................3
MAN......................................................................................................................................4
WAN.......................................................................................................................................4
4. Introduction to network architecture......................................................................................5
1. Peer-to-Peer architecture or P2P.....................................................................................5
Suitable topology for Peer to Peer..................................................................................7
2. Client-Server Architecture..............................................................................................7
Suitable topology for client-server architecture............................................................8
5. Comparison between peer to peer and client-server..............................................................9
6. Physical Layer........................................................................................................................9
I. Guided Media...................................................................................................................10
1. Twisted Pair Cables................................................................................................10
2. Coaxial cable..........................................................................................................10
3. Fiber-Optic cable...................................................................................................10
II. Unguided Media..............................................................................................................11
1. Radio waves...........................................................................................................11
2. Microwaves............................................................................................................11
3. Infrared...................................................................................................................11
4. Wi-Fi..............................................................................................................................11
7. Network Topology................................................................................................................11
I. Importance of network topology...................................................................................12
II. Classification of network topologies.........................................................................12
A. Bus Topology.........................................................................................................12
B. Ring topology........................................................................................................13
C. Mesh topology...........................................................................................................14
D. Start topology............................................................................................................16
Comparison between Mesh and Start topology....................................................................17
8. Conclusion............................................................................................................................17
References................................................................................................................................18
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1. Executive summary ( Part-02 )............................................................................................19
2. Introduction..........................................................................................................................19
3. LAN......................................................................................................................................19
Advantage of LAN...............................................................................................................19
Disadvantage of LAN..........................................................................................................19
4. Wi-Fi....................................................................................................................................20
Advantages...........................................................................................................................20
Disadvantages......................................................................................................................20
5. Comparison..........................................................................................................................20
7. ISP........................................................................................................................................21
1. Sri Lanka Telecom...........................................................................................................21
Growth of SLT................................................................................................................22
2. Dialog...............................................................................................................................22
Growth of network.........................................................................................................22
8. ISP comparison....................................................................................................................23
9. Conclusion............................................................................................................................23
References................................................................................................................................23
Table of figures
Figure 1 LAN Diagram..............................................................................................................4
Figure 2 MAN Diagram.............................................................................................................4
Figure 3 MAN Diagram.............................................................................................................5
Figure 4 Peer to Peer Architecture.............................................................................................6
Figure 5 Client-Server Architecture...........................................................................................8
Figure 6 Transmission Media Table.........................................................................................10
Figure 7 Bus Topology.............................................................................................................12
Figure 8 Ring Topology...........................................................................................................14
Figure 9 Mesh Topology..........................................................................................................15
Figure 10 Star Topology...........................................................................................................16
Figure 11 Logo of SLT.............................................................................................................21
Figure 12 Logo of Dialog.........................................................................................................22
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1. Executive summary (Part-01)
This report provides information about the main aspect of Network architecture, the physical
layer and its design and network topologies. This report include the information about
network architecture such as peer to peer and client-server, advantage and disadvantage of
these architectures, uses of network topology and comparison between them.
2. Introduction
In today’s world network becomes one of the most important and core part of human life.
Most of don’t even realize how network is having impact in our daily life. Our life just
changed dramatically in last decades because of the evolution of the networks. According to
the statistics, nowadays 55.1 percentage of world population has internet access, which is
more than 4 billion. This massive internet is also a network. If you ask how much impact we
have with network is? The best answer is think a day without WhatsApp, Facebook, Twitter,
Call or anything that you do with the mobile or laptops. That’s the disaster that every human
being can face in modern world. The world economy will fall and many terrible things will
happen because nowadays we can’t survive without network in this progressed world.
3. Introduction to network
In simple words computer network is interconnection between two or more computers or
devices, in order to share the internet, peripheral devices such as printer, scanner, etc… In
order to connect to network we need to have network components such as Network Interface
Card, Hub, Switch, Router and etc.… There are many types of network out there such as
1. LAN
2. MAN
3. WAN
To get to know about network topologies and all, we need to have short introduction about
these network types.
LAN
LAN stands for Local Area Network, which is several computers that are interconnected in
small area. LAN can be wired or wireless. For example, network connection that is inside the
home, office, hospital and some other small area.
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Figure 1 LAN Diagram
MAN
MAN stands for Metropolitan Area Network. If we connect two or more LAN connection
together that means, it’s MAN. In order to create MAN, we need to expand the LAN. To do
that we use network components such as Hub, Switch or Router.
WAN
WAN stands for Wide Area Network. WAN is network that cross MAN, connection between
countries, simple a broad network. Best example for WAN is internet.
Figure 2 MAN Diagram
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Figure 3 MAN Diagram
We get to know about these network types. There are more than these network types but these
are most common types.
4. Introduction to network architecture
In simple words, network architecture is design of network or layout of how computers and
components are connected to the network. There two types of most used network
architectures.
1. Peer-to-Peer architecture or P2P
Peer to peer network architecture is also known as tiered architecture. In this architecture
tasks are partitioned or divided between the peers in the network. Actually, every nodes in the
network is has same ability and equal. Any node in the network can become server as well as
client. The term server means, the computer or device which provides or manage the
resources within the network. The term client means, the computer that is accessing or using
the resources that is provided by the server. Peer to peer doesn’t need any centralized
controller such as server and all. A node in the peer to peer network work as resource supplier
and consumer. In simple words, computer in the networks will connect to another computer
in the network. Upload and download will happen in the same computer.
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Figure 4 Peer to Peer Architecture
Peer to Peer example:
 Torrents
 Bitcoin transaction
 File sharing through Xender and Shareit
 TOR (Onion websites)
Advantages
 Data we send through this architecture is so secured because it’s end to end encrypted.
No any middle man or server can get the data.
 It has low cost infrastructure in the p2p architecture, users use part of their disk
storage, processor or bandwidth.
 P2P network is pretty much redundant, so on delivering a nice experience to user is
much easier than client-server.
 In p2p there is no need of server. So, we don’t need to spend dedicated amount money
on server.
 If one node in the network stop working then it’s not going to down the whole
segment.
Disadvantages
 In this architecture, we have setup separate security for each nodes in the network
 There no control over the data because in peer to peer architecture there is no any
server to manage and control the data transmission.
 Insecurity, Virus, Trojan and more malwares can easily affect the computer in peer to
peer network and every computer in the network has to set its own security by itself.
 Absence of dedicated server cause lack of back system in peer to peer. All the nodes
in the network have their own backups.
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Suitable topology for Peer to Peer
Mesh topology is suitable topology for Peer to Peer architecture. There are several reasons for
that.
 In mesh topology each and every computer is interconnected with another computer.
So far, in peer to peer also all nodes are connected with every other nodes. For some
special cases we can use partial mesh topology to connect a node to several nodes in
the network
 In mesh topology we don’t have any centralized server in the network which is same
for the peer to peer architecture. There is no any centralized device in peer to peer
architecture.
 In peer to peer every node in the network is server and client in case using mesh
topology will make data transmission more effective because in mesh topology
multiple devices can transmit data simultaneously.
 If a one node fail in the network that will not affect the whole segment in the peer to
peer in this case, using mesh topology will be more efficient.
2. Client-Server Architecture
There client-server model is one of the computer will act as server which will provide
resources and manage the network. Other computers or nodes that are connected to the
network will be client which request resources from server. In this architecture, Server
computer holds the core part because it’s providing the resources. Client can’t share their
resources in this architecture, they can request the resources from server computers.
Example for this client-server, the bank provide online banking or ATM services. Clients can
request these services such as, current bank balance, online money transfer, cash withdraw
and deposit and more… In this case bank is server and customer is client.
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Figure 5 Client-Server Architecture
Advantages
 Unlike the peer to peer model, client-server architecture got a centralized
administrator/server. This centralized server will control the data transmission,
manage the network and access of users.
 In client-server architecture, Data is stored in the server and clients can back up there
data in server as well. In some case, if client lost their data they can easily recover it
from the server.
 Client-server architecture is so secured because all the access and rights are controlled
by the centralized administration.
Disadvantages
 If server gets many requests from the clients, then it’ll jam the server means, overload
will break the server.
 Client-server architecture is very expensive, it’s very expensive to manage and
configure. Servers are also very expensive.
 To monitor and manage the server, it need a professional. So it also cost more
 If something happens to server and its goes down, then the whole segment will fail.
Suitable topology for client-server architecture
There many topology will suits for client-server architecture but for the efficient network I
chose start topology as the suitable one. There are several reasons behind that.
 In client-server architecture there will be one server which will provide the resources
for the clients. So when we are connecting new client in the server, if that affect the
network then that’s not efficient. In star topology you can connect and disconnect
clients from the network any time and that’s won’t affect the network.
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 In client-server architecture, there will be many clients. By choosing star topology for
architecture we can get safe from network fail because in most of the topology, if a
node in the network fails that’ll down the whole segment.
 We can easily detect the faults in the network, in topology like bus it’s difficult to
figure the problems in the network.
 In client-server architecture, server will store the data which is go through the
network. In that case, data is more secure in the star topology rather than other
topologies like bus and ring.
 We can send the data simultaneously. It’s not possible in topologies like bus because
in that data flow is in one direction.
5. Comparison between peer to peer and client-server
Client-server architecture is built to operate the network that is based on centralized server
which will provide the resources to clients. In peer to peer all the computer or node that are
connected to the network can be server and client. This is the major difference between these
two architectures.
In client-server architecture, the centralized server will back up the data in its server but in
the peer to peer it doesn’t happen because peer to peer doesn’t have a database like in client-
server architecture. So on, peers need to have their own back up itself.
There is a case called “Bottle-Neck effect” which means, the capacity is limited by the
allocated amount of resources. This phenomenon is mostly could happen in client-server
architecture because in this model on server is providing all the clients. Bottleneck effect
chances are low in peer to peer.
In client-server architecture, server contains all the login information of clients itself. If a
client wants to connect to the server then they have to provide proper email and password but
in peer to peer, each and every nodes in the network need to have their own security such as
windows password for its security. There no any centralized devices to control the peers in
the network. In client-server architecture, there high chance to get the data when the
transmission is high compared to peer to peer. Peer to peer is direct connection, so far chance
of man in the middle attack is low.
6. Physical Layer
Below the physical layer is the place where transmission media is located and also it’s
controlled by the physical layer itself.
Transmission media is something that carry the information from sender to receiver. There
two type of transmission media.
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Figure 6 Transmission Media Table
I. Guided Media
In simple words, guided media is something that transfer the data from sender to receiver
through the physical links.
1. Twisted Pair Cables
I. STP (Shielded Twisted Pair)
These cables are surrounded and twisted by the foil in order to prevent the electromagnetic
interference between pairs of STP wires. These are commonly used in home and company to
connect them to telephone company. These cables are expensive. It’ has good performance
and speed.
II. UTP (Unshielded Twisted Pair)
This unshielded twisted pair cable doesn’t have any foil shield. This makes the cable smaller
but it can’t prevent the electromagnetic interference. These cables are less expensive and Very
speed. Compared to shielded twisted pair cables, these cables’ capacity and performance is
low. It’s best for short distance data transmission.
2. Coaxial cable
This cable is mostly used in TV companies to connect satellite to TV. This is a copper cable
that is metal shield in order prevent or block signal interference.
3. Fiber-Optic cable
Fiber-optics is cable that include glass fiber which is covered by a case. This fiber optic
cables are used for network purposes. This cables are made to transfer data to long distance in
high performance. Fiber-optic cables are mostly used for telecommunication, Internet uses
and television purposes.
10 | P a g eTransmission
media
Transmission
mediaGuided Media
Guided MediaTwisted pair
cable
Twisted pair
cableSTP (Shieled
Twisted Pair)
STP (Shieled
Twisted Pair)UTP
(Unshielded
Twisted Pair)
UTP
(Unshielded
Twisted Pair)Coaxial Cable
Coaxial CableFiber-Optic
cable Fiber-Optic
cableUnguided
Media
Unguided
MediaRadio Waves
Radio WavesMicrowaves
MicrowavesInfrared
InfraredWi-Fi
Wi-Fi

Fiber optic cables supports higher capacity of bandwidth. It can transmit the data for long
distance in high performance without losing its speed.
II. Unguided Media
Unlike guided media, unguided don’t use any sort of physical media to transfer data. It uses
electromagnetic signal as transmission medium.
1. Radio waves
In some case we have to pass our data to some other building, in the case our data have to
pass through the walls and all. One of the best way to transmit the data through the building
is radio waves. It’s easy and efficient because the antennas do have to be aligned for
transmission. Phones and FM radios are using this radio waves for the data transmission.
2. Microwaves
In order the transfer data via microwaves, the antennas should be aligned. Microwaves got
high frequency waves. These frequency is made by many transmitters. In phone we have
transmitter chip.
Mobile phones is also using microwaves for communication. Even for the television channel
distribution we use microwaves.
3. Infrared
This is used for short distance data transmission. In our daily life, we use remote to control
the TV. It also made by infrared. Wireless mouse and keyboard also using this infrared. This
infrared al penetrate through the wall.
4. Wi-Fi
The term Wi-Fi stands for wireless fidelity. Best way to understand the Wi-Fi is to home and
company or most of the public places support Wi-Fi now. To transmit wireless signal for Wi-
Fi, we need devices like router, smart phone or computer. Using Wi-Fi we can communicate
and transfer the data via wireless signals.
7. Network Topology
Network topology is the systematic and visual representation of network arrangement and
connection of nodes, connecting lines and wires.
There are two types of network topologies.
1. Physical topology
Physical topology is just like a map of network. It describes the workstation, cables and all
other components in the network visually. This physical topology is based on the physical
layer of the OSI model that we see before.
2. Logical topology
Logical topology is about how the information and data flows through the network. Logical
topology defines how data should transfer in the network. This defines the way signals react
with network and how nodes in the network communicate with each and another.
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I. Importance of network topology
1. After the advent of network topology, the evolution in network field is very huge and
efficient.
2. By knowing about topologies will give good understanding in network field. People
will know how computer network will works? And importance of it also. Through
network topologies people will get better understanding in components like router,
cables and more.
3. Network topology is helping us to improve the performance and efficient of network.
4. By using network topologies, we can effectively manage the network components and
resources.
II. Classification of network topologies
There are many network topologies out there. So far I gave here four basic network
topologies.
A. Bus Topology
In this topology all the nodes are connected to one cable. The cable that is all the nodes are
connected called “Back Bone”, which means the whole network is depends on that one and
only cable. If the back bone gets broken than the whole segment will fails. Every single data
will send and receive through this back bone. It’s a linear topology. Every devices in the
network will see (Data is visible for all nodes is the network) the data that’s send through this
cable but the computer which request the data should access it. Data is usually transmitted in
one direction in this topology. To expand a bus topology, we have to connect the two bus
cables/ back bones together. This network is most suitable for small network, such as 12 or
less devices in single bus network.
Figure 7 Bus Topology
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Pros
1. it’s so easy to add more devices in the network. Many other server and system can be add
in.
2. It is so cheap.
3. it’s best for LAN and small networks.
4. Cables that required to this network is lesser that any other network topologies.
5. Topology is best for small network.
Cons
1. Whole network works on single line. Finding a problem in this is difficult
2. Bus topology efficiency get decreased when more nodes added to network.
3. Security is not that good in this network.
4. Data send through the back bone is visible for all the nodes in the network.
5. Since data transmission is one direction, we can’t send data simultaneously.
6. If network goes down, it’s difficult to identify the problem in network.
B. Ring topology
In this topology data will travel in one way. The data will take place by one token. Every
node in network is connected to two nodes in each sides. Its’s nearly like loop. The data will
transfer one by one through the nodes until it reaches the destination. If there is many nodes
in the ring topology then the repeater is used to prevent the data lose because I’ll keep data
fresh until data reach its destination. There is topology called “Dual ring topology. In usual
ring topology data will flow in one direction but in the dual ring topology data will transmit
in both direction. This can done by creating two rings in network. One ring will flow the data
in one direction while other ring transmit the data in opposite direction.
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Figure 8 Ring Topology
Pros
1. Speed is very good because all data flows in single direction.
2. Network server doesn’t need to control the work stations.
3. Every system has equal access to resources/
4. it’s easy to figure the problem in the network because it’s point to point connection.
Cons
1. Data and information is passed through node to node so that makes it slow.
2. If any node go down the whole network get break.
3. Security is not that good in this network.
4. Moving and adding more workstations in this network can affect the network.
C. Mesh topology
In this network all computers are interconnected to each other. This allowing for most
transmission to be distributed even one of the connections goes down. In this network if a
path is broken than it will reroute by taking some other path to destination. It’s mostly used in
WAN including internet. There are two type of mesh topology. One is Full mesh topology
and Partial mesh topology.
Partial mesh topology means, some of nodes in the network connected to all the nodes in the
network while, rest of the nodes are transmit the data to certain amount of nodes in the
network. Unlike partial mesh topology, in full mesh topology all the nodes are connected to
each and every nodes in the network.
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There main two techniques in the mesh topology to transmit the data in the network. One is
routing. Routing will used to avoid broken path in the network or to find the shortest pat in
the network in order to transmit the data to its destination fast as possible. Second one is
flooding. This is transferring the data to each nodes in the network. Using this make the
network overload.
Figure 9 Mesh Topology
Pros
1. Can manage high amount of traffic in network because data in this network will transmit
simultaneously
2. If a one device get failure that not going to break the network or transmission of data.
3. Adding more devices in the network is not going to disrupt the data transmission that
happens in the other devices
4. In some router protocols travelling packets find the quickest route path in the network.
5. Robust because in flooding all the nodes will have the data, so far data losing is less.
Cons
1. Its cost more than other network topologies
2. Building, maintaining and this topology takes time and it’s difficult.
3. There are more connection than we want, so because of this redundancy its cost high.
4. Using flooding will overload the network.
5. Data isolation and redundancy will happen in flooding technique
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D. Start topology
In star topology all nodes are individually connected to a hub or switch. Every single
computer in the network will controlled by central point which is hub or switch. Star
topology takes many cables than any other topology but the thing is we can get more benefits
from it than other topology. We can see the star topology in most of the places like wise, in
home. In that network, router or switch or hub is centralized administrator. Ethernet cable or
twisted pair cable is used to connect to the network, in some case we use fiber optics also. If
single node in the network goes down that not going to shut the whole segment. All the data
will go through the centralized administrator before it reach its destination. It’s mostly used in
10BaseT, 100BaseTX.
Figure 10 Star Topology
Pros
1. Connecting and disconnecting devices from network is easy
2. In this network, all devices are controlled and monitored by central point (Hub or Switch)
3. If a one device in network got problem that won’t affect the whole network because all
nodes are connected individually
4. Not much cables is needed to configure the star topology
Cons
1. More devices in the network going to cost more money.
2. Capacity of central junction affects the performance of all the devices in network.
3. If central hub gets down that will shuts the whole segment.
4. it’s expensive to install and maintain.
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Comparison between Mesh and Start topology.
 In start topology we use centralized hub for controlling the data flow. All the nodes in
the network is connected to it and data will go through it. On the other hand, in mesh
topology, each node is connected other nodes. In this case, connecting and removing a
device in the star topology way to easy compared to mesh topology. Mesh uses point
to point connection, so far, it is making the things complicated.
 In star topology the whole segment is based on centralized hub. If it goes down then
the whole segment will fail but in mesh topology its different there’s nothing like
centralized hub and it’s robust.
 In mesh topology, if a path get broken it’ll reroute and use another path to transmit the
data. On the other hand, in the star topology, if a path get broken there no any
alternative way to transmit the data to its destination.
 Wiring and design in mesh is complex compared to star topology.
 Mesh topology is expensive compared to star topology because more nodes we adding
will increase the cost because of wires and input or output ports.
According to comparison, star topology is more convenient if less cost is aim but if we
consider the speed and security then mesh is best.
8. Conclusion
In this progressed world, internet is one of the most valuable resource that human ever found.
We got this internet because of networks and internet is also called as “Network of
networks”. In this report first we saw about the network types for example LAN, WAN and
MAN. After that we have network architecture. There are two types of architectures, one is
Client-Server model and another one is Peer to Peer model. In order to manage the network
we need design of it. That is Network Topology. There are many topologies, best topology for
client-server model in my view is star topology because of several reasons and suitable
topology for peer to peer is mesh topology. Even though there are many topologies out there,
every topology got its advantages and disadvantages but nowadays star topology and mesh
topology are the most usable and efficient topologies.
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References
 Techgenixcom. 2018. TechGenix. [Online]. [20 March 2019].Available
from: http://techgenix.com/network-topology/
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from: https://blog.finjan.com/a-closer-look-at-network-topology/
 Techgenixcom. 2018. TechGenix. [Online]. [20 March 2019].Available
from: http://techgenix.com/network-topology/
 Claranet. 2019. Claranet. [Online]. [20 March 2019].Available from:
http://www.darvill.clara.net/emag/emagmicro.htmhttps://www.csesta
ck.org/importance-of-network-topology
 Lifewirecom. 2019. Lifewire. [Online]. [20 March 2019].Available
from: https://www.lifewire.com/fiber-optic-cable-817874
 Geeksforgeeksorg. 2018. GeeksforGeeks. [Online]. [20 March
2019]. Available from: https://www.geeksforgeeks.org/types-
transmission-media/
 Ukessayscom. 2019. UKEssayscom. [Online]. [20 March
2019]. Available from:
https://www.ukessays.com/essays/information-technology/the-
computer-networks-information-technology-essay.php
 Devto. 2019. The Practical Dev. [Online]. [20 March 2019].Available
from: https://dev.to/cadellsinghh_25/types-of-network-architecture-
56i7
 Quoracom. 2019. Quoracom. [Online]. [20 March 2019].Available
from: https://www.quora.com/What-problem-does-peer-to-peer-
networking-solve
 Quoracom. 2019. Quoracom. [Online]. [20 March 2019].Available
from: https://www.quora.com/What-are-some-advantages-and-
disadvantages-of-client-server-networks
 Wisdomjobscom. 2019. Wisdom Jobs. [Online]. [20 March
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1. Executive summary ( Part-02 )
Global university has dedicated internet leased line connected to all the terminals through the
campus. Students and faculty are free to access the internet. Wi-Fi faculty should be provided
to the related company according to the new design, and you are supposed to analyze the
importance of LAN technology and the Wi-Fi technology and choose the best out of it
showing the key points. There are many ISPs in Sri Lanka. This report provide two most
popular ISPs in Sri Lanka. This report include the details, growth and comparison between
them.
2. Introduction
We’re living in era which information and communication are most important in our daily
life. Where ever we go information and communication is essential. Nowadays, we can get
these information and communication easily like never before. The only reason behind this is
internet. A massive and best invention of human being. Internet is everywhere, in college,
campus, hospital, home and etc… The reason behind this is we know the importance of
internet. In order to get the internet connection we use many things. There many solution out
there to get the internet connection such as LAN, Wi-Fi and more. This report will provide
justification of which one is best.
3. LAN
LAN means Local Area Network. Which is connecting several computers or devices in small
area. In order to do this we mostly use Ethernet cable to connect the devices to network. Not
only that we also use components such as router, hub, switch and more.
Advantage of LAN
 All the nodes are connected to one network. If any files or resources needed then that
can be shared from the computer which has the resources. In case, we don’t need to
buy separate printer, scanner or any resources. We can use one for all in the LAN
network.
 We can use Client-Server network. In that case, we can store data in server computer.
If any user in the network needs data then it can request the data from server.
 If a node in the network has internet than it can be shared to all the nodes in the
internet.
 Data in LAN is so secured because if we made some changes in data then the new
data can be access by the nodes in the network. It’s time saver. Server can only access
able by the authorized users.
Disadvantage of LAN
 If server doesn’t has proper security configuration then unauthorized users also can
access the server. In case, data is not secured and it can be leaked.
 If an organization needs LAN setup then it’ll cost more to start it because they have to
buy the hardware equipment in order to setup the LAN network. If the company or
organization is large then they need a network technician in order to manage and
maintain the network, so far they have to pay salary then its additional cost.
 LAN work under the small area such as office, school, campus and more.
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4. Wi-Fi
Wi-Fi stands for wireless fidelity. It’s wireless connection that connects the devices to
internet. Wi-Fi doesn’t use any physical devices.
Advantages
 It’s easy to connect many devices in organization because Wi-Fi is more convenient.
 Connecting and disconnecting the devices is easier and that’ll not disrupt other
devices in the network.
 Internet can be access from anywhere and we don’t need any wire or physical
components to connect the devices to internet.
 Nowadays new devices are already coming with the antennas and adapter that are
need in order to connect the devices to Wi-Fi.
 We don’t need any special persons to manages the Wi-Fi because it easier to manage
and maintain the network.
 It’s not too expensive because we don’t need any cables or any other components to
connect devices to the network.
Disadvantages
 We though Wi-Fi comes with the fast internet connection, we don’t’ get that in every
places but in LAN we can get 10 Gbps speed.
 Wi-Fi signal can go through the walls but signal get reduced in some cases like
concrete wall or some other power wall. So the distance and speed are limited by the
signal
 Wi-Fi has many ways to secure but proper configuration is must to get the proper
security.
 802.11g network got tens of meters distance in the standard equipment
5. Comparison
I chose LAN as the best network for the university because of several reasons.
Since 802.11 n (2009), there is no any new Wi-Fi has improved on the maximum range of
230 feet.
Although we have gigabit Wi-Fi available, even we cannot get gigabit speed at all location
but in LAN we can get 10Gbps in maximum.
On common the university has limited investments. Compared to Wi-Fi, LAN connection is
relatively less-expensive. To setup, maintain and troubleshoot. LAN’s troubleshooting also
quick and cost effective.
LAN is very adaptable. As employees get shuffled in teams and departments and new hires
get into company, a LAN can make sure that all employees and computers are stays
connected.
A LAN is monitored by small team. We’re using router or switch or hub, so we have firewall
to make the network more secure. All devices must provide username and password to get
access to network. That is even more secure for university.
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In case of Wi-Fi, it’s slower than LAN. Speed on most of the Wi-Fi is far slower (1-54Mbps)
than the slowest wired network (100 Mbps).
For now, 801.11 aj is the most recently approved standard in May 2018.
801.11 ah
This is targets lower energy consumption and creates et4ended range of Wi-Fi network that
can go beyond the reach of a typical 2.4 – 5 GHz.
Comparing to Bluetooth its need to less power.
802.11 ac
Its dual band technology that support simultaneous connections on the both the 2.4GHz – 5
GHz Wi-Fi bands. It’s also offers backwards compatibility to 802.11 b/g/n and bandwidth
rated up to 1300 Mbps. On the 5 GHz band plus up to 450Mbps on 2.4Ghz.
802.11 ac is fastest maximum and best signal range even though it’s way too expensive to
implement. Performance and improvement are noticeable in high bandwidth applications.
7. ISP
ISP stands for Internet Service Providers. Which is an organization that provides internet
access for the country. ISP is also providing services like domain name registration, web host
and more. There are many ISP in Sri Lanka. Such as
 Sri Lanka Telecom
 Dialog
 Lanka Bell
More…
1. Sri Lanka Telecom
Figure 11 Logo of SLT
Sri Lanka Telecom is one of the telecommunication service provider in Sri Lanka. It’s a
leading internet service provider and backbone infrastructure service provide in Sri Lanka.
SLT is providing many services in Sri Lanka. Such as
 Next generation technology like ADSL2+, VDSL2, Optical fiber, Carrier- Grade Wi-
Fi, and Mobile 4g.
 Voice calling
 Data hosting
 Cloud Computing Services
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 IPTV
 Mobile based customer services
 Mobitel 3G and 4G LTE networks.
Growth of SLT
1859 - First submarine cable laid between India and Sri Lanka
1996 – Internet and email services introduced in Sri Lanka
2000 – First optical fiber connect 15 cities in Sri Lanka
2003 – SLT launches its internet service on ADSL technology
2005 – First SLT’s CDMA network introduced
2007 – SLT’s broadcasts its IPTV
2008 – Bandwidth upgrades to 3G
2009 – SLT’s IPv6 deployment in ISP network
2012 – Internet speed upgrades up to 10Mbps
2014 – SLT launches 4G/LTE technology
SLT launches cloud computing
SLT launches first public Wi-Fi hotspots in Sri Lanka
2015 – Launches SLT’s fiber optics service
2017 – Successfully tested 5G LTE technology
2. Dialog
Figure 12 Logo of Dialog
Dialog Axiata is one of the largest telecommunication service providers in Sri Lanka. Dialog
owns 44 percentage of Sri Lanka mobile market. It’s 5th largest company in Sri Lanka. Dialog
providing various service in Sri Lanka such as…
 Dialog operates 2.5G, 3G, 4G LTE networks in Sri Lanka
 Dialog TV
 Fixed line and Broadband services
Growth of network
First Dialog was introduced as MTN Networks in 1993. After two years it change its brand
name as “DialogGSM”. It’s the first South Asia Company that’s using GSM technology.
Dialog becomes more popular in 2000. It was able get the leading position in Sri Lanka
mobile market. In 2001 starting its ISP operations by launching GPRS and MMS services.
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In 2006 Dialog launches its DialogTV by taking over the company called CBN SAT for 4.6
million USD.
8. ISP comparison
Like I included in this report, there are many ISP in Sri Lanka. SLT and Dialog are the
competitor in today’s scenario. According to my view SLT is the best ISP in Sri Lanka
because of several reasons.
 SLT providing many facilities like cloud computing, fastest internet connection
through the fiber optics and many facilities which are other ISPs like dialog not
providing.
 SLT has decent package, means its cost is not low and not high it has average price in
current market compared to Dialog or any other ISPs in Sri Lanka
 SLT is one of the oldest company in Sri Lanka, therefore they got trust of Sri Lanka
people’s and also its majority shares holds by the government of Sri Lanka so it’s
trustworthy than private company like Dialog
 SLT providing many ways to get the internet connection like 4G/LTE, Mega line and
fiber optics. It’s also successfully tested out the 5g Technology.
9. Conclusion
In this report we saw about LAN which is stands for Local Area Network, Wi-Fi which is
stands for wireless fidelity. These two got its own advantages and disadvantages. According
to my view LAN is best network for internet access for the university that given in the
scenario because of several reasons like speed and cost. ISP stands for Internet Service
Providers. There the one who provide internet connection, they also provide many services.
In Sri Lanka there are many ISPs out there, for instance SLT, Dialog, Lanka bell and more.
This report include comparison between like major ISPs in Sri Lanka.
References
 Itreleasecom. 2018. IT Release. [Online]. [20 March 2019]. Available
from: http://www.itrelease.com/2018/07/advantages-and-
disadvantages-of-local-area-network-lan/
 Quoracom. 2019. Quoracom. [Online]. [20 March 2019]. Available
from: https://www.quora.com/What-are-the-advantages-and-
disadvantages-of-WiFi
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 Computergapcom. 2019. Computergapcom. [Online]. [20 March
2019]. Available from:
http://www.computergap.com/2014/11/advantages-and-
disadvantages-lan-local-area-network.html
 Wikipediaorg. 2019. Wikipediaorg. [Online]. [26 March
2019]. Available from: https://en.wikipedia.org/wiki/Dialog_Axiata
 Slt, . 2019. SLT about us. [Online]. [26 March 2019]. Available
from: /en/about-us
 Slt, . 2019. Milestones of SLT. [Online]. [26 March 2019]. Available
from: /en/about-us/milestones
Slide 1
World without internet is waste because it’s our current resource of information and
communication.
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Slide 2
In todays world 55.1 percentage of population has internet connection. It means 4 billion of
people. How we got this internet. What is behind that? Obviously it’s network.
Slide 3
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Welcome slide of the presentation
Slide 4
what is network? A small introduction to network.
Slide 5
Introduction to story part in presentation. Story is about the evolution of network. This story
is to make proper understanding of network.
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Slide 6
Since the start of the time, we communicate and share the information. Even in the Stone
Age.
Slide 7
At first, we use languages in order to communicate and share the information.
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Slide 8
After that we came up with the letter, email, phone, and more
Slide 9
Nowadays, we have most efficient way of information sharing and that’s internet.
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Slide 10
Starting slide of the network
Slide 11
Basic things that a person need to know in order to get the understanding of the network.
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Slide 12
First, cables
In order to connect two or more computer we need some basic things. First one is
components. One of the main component is cable. There are many types of cables like RJ 45,
UTP and STP
Slide 13
We use these cables to connect the device to network.
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Slide 14
Ways to expand the network.
Slide 15
To expand the network we use switch and hub. Switch is like a boy and hub is like a girl. And
explanation about the switch and hub because hub will deliver all the data to connected nodes
and the switch will send the data only to the requested node.
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Slide 16
Introduction to network architectures
Slide 17
First one is client server architecture and introduction to it.
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Slide 18
Uses of client- server architecture and real life example for model.
Slide 19
Next, introduction to peer to peer architecture.
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Slide 20
Real life examples for peer to peer architecture.
Slide 21
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Introduction to Network Topologies
Slide 22
Types of network topology
Slide 23
Introduction to bus topology.
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Slide 24
Introduction to ring topology.
Slide 25
Introduction to mesh topology.
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Slide 26
Introduction to star topology.
Slide 27
Introduction to network types.
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Slide 28
First, The Introduction to Local area network.
Slide 29
The Introduction to metropolitan area network.
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Slide 30
The Introduction to Wide area network.
Slide 31
End of the presentation and the conclusion for it.
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