This document provides an overview of computer networking. It defines a network as a group of interconnected computers that share resources through communication links. It discusses the development of early networks like ARPANET and defines a computer network. It describes applications of networks like resource sharing, communication, and information sharing. It also categorizes networks based on area into LAN, MAN, WAN, and PAN and discusses characteristics of each. Additionally, it outlines hardware used in networks like NICs, routers, switches and modems. Finally, it differentiates between peer-to-peer and client-server networks.

1. COMPUTER NETWORKING

2. Introduction
• A network is a group of Interconnected
computer systems by means of a shared
communications link.
• A computer network is nothing but two or
more computers and devices like printers
connected together.
• A network is a group Interconnected sharing
services and Interacting by means of shared
communications link. A network therefore
requires two or more individual with
something (data) to share

3. In 1969 the Department of Defense (DOD) of USA
developed a network first and named it as ARPA Net
(Advance Research Project Administrative Network).
A computer network may be defined
As a group of computers that are capable
of sharing resources.
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Linking up of two or more autonomous
computers & peripherals with the help
of a media (wire , OFC, Wi-Fi, satellite etc)
and utilization of resources over the network by different users.

4. Applications of Networks
Resource Sharing
Hardware (computing resources, disks, printers)
Software (application software)
Information Sharing
Easy accessibility from anywhere (files, databases)
Search Capability (WWW)
Communication
Email
Message broadcast
Remote computing

5. N/W According to AREA
• LAN ( Local Area N/W)
• MAN(Metropolitan Area N/W
• WAN(Wide Area N/W)
• PAN(Personnel Area N/W)

6. LAN
A Local area Network is a group of
computers and network
communication devices inter
connected within a geographically
limited area such as campus or
building.
LANs are characterized by
They transfer data at high speed. They
exist in limited area-building, campus.
Their technology is generally less
expensive.

7. MAN
A Metropolitan Area Network
is a group of computers and network
communication devices inter
connected within a geographically
limited area such as city

8. WAN
Wide Area Network interconnects
LAN. WAN may be located entirely within a
state or country or it may be inter connected
around the world. WAN are characterized by
the following.
They exist in a widely scattered
geographical area-country continent. They are
more susceptible to error due to the large
distance data travel. They inter connect
multiple LANs

9. The Local Network (LAN)
Client
ClientClient
Client Client
Client

10. Metropolitan Area Network (MAN)

11. • Wide Area Network

12. Hardware device use for Networks
• Network Interface Card (NIC)
• Routers
• Switch
• Modem

13. Network Interface Card (NIC)
• NIC provides the physical interface between computer and cabling.
• It prepares data, sends data, and controls the flow of data. It can also
receive and translate data into bytes for the CPU to understand.
• The following factors should be taken into consideration when choosing a
NIC:
1. - Preparing data
2. - Sending and controlling data
3. - Configuration
4. - Drivers
5. - Compatibility
6. - Performance

14. Based on the role of computers attached to a
network, Networks are divided into two types:
1. Peer to Peer Network
2. Clint Server Network

15. A peer to peer network is characterized by the lack of central control
over the network. There is no dedicated server in peer to peer network.
Every computer act as a client and a server. Resources can be shared by
any one who has access to the network.

16. 1. No extra investment in server hardware and software
is required
2. The set-up is easy
3. Network administrator is not required
4. User can control the sharing of resources
5. Low cost

17. 1. The security weak
2. Users are required to administer their own computer
3. There is additional load on the computers because of
resource sharing
4. It is not possible to handle as many network connection
as in server based networks.

18. S
E
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S
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A server based network is characterized by servers that reside on the
network and provide security and administration.
This type of network has clients that rely on the services that the server
provide. Servers are optimized to quickly service request from network
client and to ensure the security of files and directories.

19. 1. Strong central security
2. Central file storage
3. Functionality of servers to pool the available
hardware and software lowering over all cost
4. Easy management of a large number of users
5. Freeing users from the task of managing the
shared resources

20. 1.Dedicated software
2.Expensive network operating system and
client licenses
3.Required a dedicated network administrator
4.On failure of server the whole network is
effected