This document provides an overview of computer networks, including definitions, types of networks and topologies. It defines a computer network as allowing devices to exchange data via physical connections. The main types of networks covered are personal area networks (PANs), local area networks (LANs), metropolitan area networks (MANs) and wide area networks (WANs). The document also discusses peer-to-peer and client-server network architectures, and various network topologies including star, bus, ring and tree configurations.

2. CONTENTS:
Introduction
Types Of Networks
Types Of Network Architecture
Network Topology

3. INTRODUCTION:
 A computer network is a telecommunications network that allows computers to
exchange data.
 The physical connection between networked computing devices is established
using either cable media or wireless media.
 The best-known computer network is the internet.
 For example, it may connect computers, printers, scanners and cameras

4. COMMUNICATIONS:
 Communication is about the transfer of information from a sender, across a distance
to a receiver.
 Communication is an act of transmitting message.

5. COMPUTER NETWORK COMMUNICATION:
 We transmit information or data by using two types of signals, namely analog and
digital.
 Computers communications with digital signals.
 The order forms of communications technology, such as telephones and radios, use
analog signals.

6. TYPES OF NETWORKS:
Based on the size and the coverage area, networks are categorized
into the following types:
◦ Personal Area Networks (PANs)
◦ Local Area Networks (LANs)
◦ Metropolitan Area Networks (MANs)
◦ Wide Area Networks (WANs)

7.  Local Area Network(LAN):
LAN is one of the simplest types of computer networks in which
computers are connected together over the span of small distances. This
type of network is perfect for sharing resources like printers or data storage.
 Personal Area Network(PAN):
In a personal area network, there is an interconnection of information
technology that organized around an individual person typically within a
range of 10 meters. This type of computer network can also be
interconnected without any need for wires to the internet.

8.  Wide Area Network(WAN):
A WAN is a complex type of computer network that connects the computer together over
larger distances. It allows them to have communication no matter how far they are from
each other. One of the best examples of a WAN is internet through computers can connect
all around the world.
 Metropolitan Area Network(MAN):
There is an involvement of a computer network that spreads across the whole city in the
metropolitan area network. It is bigger than a LAN and covers an area that can range from
many miles to ten miles. The major use of the MAN is to connect many LANs together
for forming a larger network.

9. TYPES OF NETWORK ARCHITECTURES:

10. What is Network Architecture?
First and foremost, what is network architecture? It's basically the physical and
logical design which refers to the software, hardware, protocols and the media of
transmission of data. Simply put, it refers to how computers are organized and
how tasks are allocated among these computers. The two types of widely used
network architectures are peer-to-peer aka P2P and client/server aka tiered.

11. TYPES OF NETWORK ARCHITECTURES:
Peer-to-Peer Architecture.
Client/Server Architecture.

12. Peer-to-Peer Architecture:
 In a peer-to-peer network, tasks are allocated to every device on the network.
Furthermore, there is no real hierarchy in this network, all computers are considered
equal and all have the same abilities to use the resources available on this network.
Instead of having a central server which would act as the shared drive, each computer
thats connected to this network would act as the server for the files stored on it.

13. ADVANTAGES:
 Does not require a dedicated server which means its less costly.
 If one computer stops working, the other computers connected to the network
will continue working.
 Installation and setup is quite painless because of the built-in support in modern
operating systems.

14. DISADVANTAGES:
 Security and data backups are to be done to each individual computer.
 As the numbers of computers increases on a P2P network... performance, security,
and access becomes a major headache.

15. Client/Server Architecture:
 In a client/server network, a centralized, really powerful computer(server) acts
as a hub in which other computers or workstations(clients) can connect to. This
server is the heart of the system, which manages and provides resources to any
client that requests them.

16. ADVANTAGES:
 Resources and data security are controlled through the server.
 Not restricted to a small number of computers.
 Server can be accessed anywhere and across multiple platforms.

17. DISADVANTAGES:
 Can become very costly due to the need of a server as well as networking
devices such as hubs, routers, and switches.
 If and when the server goes down, the entire network will be affected.
 Technical staff needed to maintain and ensure network functions efficiently.

18. NETWORK TOPOLOGY:

19. TOPOLOGY:
Topology refers to the layout of connected devices on a network.
• Here, some logical layout of topology.
Mesh
Star
Bus
Ring
Tree and Hybrid

20. MESH TOPOLOGY:
• Here every device has a point to point link to every other device.
• Node 1 node must be connected with n-1 nodes.
• A fully connected mesh can have n(n-1)/2 physical channels to link n devices.
• It must have n-1 I/O ports.

21. DISADVANTAGES:
• The amount of cabling and the number of I/O ports required are very large. Since every
device is connected to each devices through dedicated links.
• The sheer bulk of wiring is larger then the available space.
• Hardware required to connected each device is highly expensive.
APPLICATIONS:
• Telephone Regional office.
• WAN.(Wide Area Network).

22. STAR TOPOLOGY:
• In star topology, all the devices are connected to a single hub through a cable.
This hub is the central node and all other nodes are connected to the central
node.

23. ADVANTAGES:
• If N devices are connected to each other in a star topology, then the number of cables
required to connect them is N. So, it is easy to set up.
• Each device requires only 1 port i.e. to connect to the hub, therefore the total number of
ports required is N.
• It is Robust. If one link fails only that link will affect and not other than that.
• Easy to fault identification and fault isolation.
• Star topology is cost-effective as it uses inexpensive coaxial cable.
DRAWBACKS:
• The cost of installation is high.
• Performance is based on the single concentrator i.e. hub.

24. BUS TOPOLOGY:
• It is a network type in which every computer and network device is connected to a single
cable. It is bi-directional. It is a multi-point connection and a non-robust topology because
if the backbone fails the topology crashes.

25. ADVANTAGES:
• If N devices are connected to each other in a bus topology, then the number of cables required to
connect them is 1, known as backbone cable, and N drop lines are required.
• Coaxial or twisted pair cables are mainly used in bus-based networks that support up to 10 Mbps.
• The cost of the cable is less compared to other topologies, but it is used to build small networks.
• Bus topology is familiar technology as installation and troubleshooting techniques are well known.
DRAWBACKS:
• A bus topology is quite simpler, but still, it requires a lot of cabling.
• If the common cable fails, then the whole system will crash down.
• Security is less

26. RING TOPOLOGY:
In a Ring Topology, it forms a ring connecting devices with exactly two
neighboring devices. A number of repeaters are used for Ring topology with a
large number of nodes, because if someone wants to send some data to the last
node in the ring topology with 100 nodes, then the data will have to pass through
99 nodes to reach the 100th node. Hence to prevent data loss repeaters are used in
the network.
The data flows in one direction, i.e. it is unidirectional, but it can be made
bidirectional by having 2 connections between each Network Node, it is
called Dual Ring Topology. In-Ring Topology, the Token Ring Passing protocol
is used by the workstations to transmit the data.

27. ADVANTAGES:
• he data transmission is high-speed.
• The possibility of collision is minimum in this type of topology.
• Cheap to install and expand.
• It is less costly than a star topology.
DRAWBACKS:
• The failure of a single node in the network can cause the entire network to fail.
• Troubleshooting is difficult in this topology.
• The addition of stations in between or the removal of stations can disturb the whole topology.
• Less secure.

28. TREE TOPOLOGY:
• This topology is the variation of the Star topology. This topology has a hierarchical
flow of data. In Tree Topology, protocols like DHCP and SAC (Standard Automatic
Configuration ) are used.

29. ADVANTAGES:
• It allows more devices to be attached to a single central hub thus it decreases the distance
that is traveled by the signal to come to the devices.
• It allows the network to get isolated and also prioritize from different computers.
• We can add new devices to existing network.
• Error detection and error correction are very easy in a tree topology.
DRAWBACKS:
• If the central hub gets fails the entire system fails.
• The cost is high because of the cabling.
• If new devices are added, it becomes difficult to reconfigure.

30. HYBRID TOPOLOGY:
This topological technology is the combination of all the various types of topologies we
have studied above. Hybrid Topology is used when the nodes are free to take any form. It
means these can be individuals such as Ring or Star topology or can be a combination of
various types of topologies seen above. Each individual topology uses the protocol that
has been discussed earlier.

31. ADVANTAGES:
• This topology is very flexible.
• The size of the network can be easily expanded by adding new devices.
DRAWBACKS:
• It is challenging to design the architecture of the Hybrid Network.
• Hubs used in this topology are very expensive.
• The infrastructure cost is very high as a hybrid network requires a lot of cabling and
network devices.

32. THANKYOU!