The document provides an overview of basic networking concepts. It defines a network as two or more connected electronic devices like computers. A server is described as a powerful central computer that provides services to other devices called clients. It also outlines two common network models - client-server, where a server provides resources and clients access them, and peer-to-peer, where each device can act as both client and server. The benefits of networks include sharing hardware, software, and data between multiple users.

1. Lesson 2: Basic
Concepts of Networking

2. What is a network?
• A network is two or more computers (or other electronic
devices) that are connected together, usually by cables or
Wi-Fi.
• Some computer networks will have a server

3. What a server?
• A server is a powerful computer that often acts as a central
hub for services in a network, e.g emails, internet access and
file storage.
Each computer connected to a server is called a client.

4. Standalone computer
• A computer that is not connected to a network

5. Network Models
1. Client-Server
2. Peer-to-Peer

6. Client-Server
• The Client-Server network model is widely used network model.
Server is a powerful system that stores the data or information in it. On
the other hands,
the Client is the machine which let the users access the data on the
remote server.

7. • The system administrator manages the
data on the server. The client machines
and the server are connected through
a network. It allows the clients to
access data even if the client machine
and server are far apart from each
other.
• In Client-Server model, the client
process on the client machine sends
the request to the server process on
the server machine. When the server
receives the client request, it lookouts
for the requested data and send it back
with the reply.
As all the services are provided by
a centralized server, there may be
chances of server
getting bottlenecked, slowing
down the efficiency of the system.

8. Peer-to-Peer
• Unlike Client-Server, the Peer-to-Peer model does not distinguish
between client and server instead each node can either be a client or
a server depending on the whether the node
is requesting or providing the services.
• Each node is considered as a peer.

9. To become a part of peer-to-peer, a
node must initially join the network.
After joining it must start to provide
services to and must request the
services from other nodes in the peer-
to-peer system.

10. Differences Between Client-Server and Peer-to-Peer Network
1.The key difference between Client-Server and Peer-to-Peer network is
that there is a dedicated server and specific clients in the client-server
network model whereas, in peer-to-peer each node can act
as both server and client.
2.In the client-server model, the server provides services to the client.
However, in peer-to-peer, each peer can provide services and can
also request for the services.

11. 3. In the client-server model, sharing information is more important
whereas, in peer-to-peer model connectivity between peers is
more important.
4. In the client-server model, data is stored on a centralized server
whereas, in peer-to-peer each peer has its own data.
5. In peer-to-peer model, the servers are distributed in a system, so
there are fewer chances of server getting bottlenecked, but in the
client-server model, there is a single server serving the clients, so
there are more chances of server getting bottlenecked.

12. 6. The client-server model is more expensive to implement than peer-
to-peer.
7. The client-server model is more scalable and stable than peer-to-
peer.

13. What are the benefits of a network?
Using a network allows you to share:
• hardware, such as a printer
• software, allowing multiple users to run the same programs on
different computers
• data, so that other people can access shared work and you can
access your data from any computer on the network

14. We use a huge network on a daily basis and this is called the
INTERNET.

15. What problems can occur with a
network?
• If we connect computers or devices together in a network we
can expose ourselves to some problems.
• If the network breaks, this can make a number of tasks it is
used for quite difficult.
• If computers and devices are networked together, we can
expose ourselves to hackers and viruses.

17. Types of network
• PAN (Personal Area Network)
• LAN (Local Area Network)
• MAN (Metropolitan Area Network)
• WAN (Wide Area Network)

18. What is a personal area network
(PAN)?
• A personal area network (PAN) connects electronic devices
within a user's immediate area. The size of a PAN ranges from
a few centimeters to a few meters. One of the most common
real-world examples of a PAN is the connection between a
Bluetooth earpiece and a smartphone.
• PANs can also connect laptops, tablets, printers, keyboards,
and other computerized devices.
• PAN network connections can either be wired or wireless.

19. What Is Local Area Network (LAN)?
A local area network is when computers or devices are
connected together over a small geographical area, such as
within a home, a building or one site.
A LAN can be created to share data or hardware such as a
printer, or to share an internet connection.

21. Attributes of LAN Network:
• The data transmit speed in the LAN network is relatively higher than the other
network types, MAN and WAN.
• LAN uses private network addresses for network connectivity for data and
service exchange, and it uses cable for network connection, decreasing error
and maintaining data security.

22. Advantages and Disadvantages of LAN Network
Advantages Disadvantages
Transmission of data and services is relatively higher
than other network connections.
Need constant administration of
experienced engineers for
functioning.
The Network Server acts as a central unit for the whole
network.
Probability of leak of sensitive
data by LAN administration.

23. What Is Metropolitan Area Network (MAN)?
The Metropolitan Area Network (MAN) is a network type that covers the network
connection of an entire city or connection of a small area. The area covered by
the network is connected using a wired network, like data cables.

24. Attributes of MAN Network:
• Network covers an entire town area or a portion of a city.
• Data transmission speed is relatively high due to the installation of optical
cables and wired connections.

25. Advantages and Disadvantages of MAN
Network:
Advantages Disadvantages
Provides Full-Duplex data transmission in the network
channel for devices.
High probability of attack from
hackers and cybercriminals due to
large networks.
The network connection area covers an entire city or
some parts using the optic cables.
The need for good quality
hardware and the installation cost
is very high.

26. What Is Wide Area Network (WAN)?
A wide area network is when computers or devices are
connected together over a large geographical area.
For example, a company with an office in London and another in
Beijing would use a WAN to allow the employees to share one
network.
Some companies will connect a number of LANs in different
areas together to create a WAN. The biggest WAN we know is
the internet.

28. Attributes of WAN Network:
• The speed of the WAN data transfer is lower than in comparison to LAN and
MAN networks due to the large distance covered.
• The WAN network uses a satellite medium to transmit data between multiple
locations and network towers.

29. Advantages and Disadvantages of WAN
Network:
Advantages Disadvantages
This network covers a high geographical area and is
used for large-distance connections.
High cost to set up the network
and the Support of experienced
technicians is needed to maintain
the network.
They also use radio towers and connect channels for
users.
It is difficult to prevent hacking
and debug a large network.

30. Thank you for listening 😊!