The document discusses computer networking and network models. It provides an overview of the purpose of computer networking including sharing resources, reducing costs, and quick information exchange. It then describes the seven layer OSI model and the four layer TCP/IP model, explaining the functions of each layer such as the physical, data link, network, and transport layers. Finally, it briefly introduces internetworks, the Internet, the World Wide Web, and different types of e-commerce.

1. COMPUTER NETWORKING
Submitted to : Sapan Jain
Submitted by : Vishal Kumar
CS-3
1st Sem

2. The interconnection of computers and various devices
into a strategic infrastructure is called computer
networking.
INTRODUCTION

3.  Sharing of resources
 Cost reduction
 Performance increased
 Quick exchange of information
 Minimum loss of informaton
 Reduced redundancy
PURPOSE OF COMPUTER NETWORKING

4. The first architecture model for networking of computers was
purposed by the international standard organisation (ISO) in
1983.
The OSI model is a seven layered architecture to provide the
framework for design of computer networking and for internat -
ionalization of the protocol used in computer network.
ISO-OSI MODEL

5. ISO-OSI MODEL

6. 1. Physical
2. Data link
3. Network
4. Transport
5. Session
6. Presentation
7. Application
The seven layers of OSI model

7. Physical layer
The lowest layer of the OSI reference model has been identified
as the physical layer, which is responsible for direct interaction
with the hardware and networking devices to establish physical
communication between the end user computers.
THE FUNCTIONS OF DIFFERENT LAYERS

8. Data link layer
This layer defines the format of data called frames . The data link
layer collects packets from the network layers to form packet
which are then transmitted over the physical network line

9. Network layer
The network layer is concerned with the transmission of packets
from the source computer to the destination computer. It deals
with data traffic on the network. It is responsible for identifying
the way in which data is transmitted over the network from one
devices to another.

10. Transport layer
The important function of transport layer is to receive the data
from the and to segment the data into packets for transport to
the network layer, and ultimately across the network in the
proper sequence

11. Session layer
The session layer is mainly responsible for establishing, managing
and terminating the session/ connection between the computers
on the network and notifying the errors that occurred on the
layers above it.

12. Presentation layer
The presentation layer ensures that the information sent from
the application layer of one system must be readable by that of
another system

13. Application layer
The topmost or the highest layer of the OSI reference model,
which provides an interface for the end user operating a device
connected to a network through which users can communicate
and transfer data on the network.

14. In 1974, the TCP/IP model was developed by Defence Advance
Research Project Agency (DARPA) on the lines of the OSI model.
DARPA is a party of US Department of Defence.
TCP/IP stands for transmission control protocol/internet
protocol. It is derived from the names of two major protocols in the
family of protocols, that is the TCP and IP protocols. The TCP/IP is a
family of protocols that represents the family of way in which
communication are carried out over a network.
TCP-IP MODEL

15. TCP/IP model has four
layers
 Application layer
 Transport layer
 Network (Internet) layer
 Network Interface layer

16. ISO-OSI MODEL & TCP/IP MODEL

17. An inter-network is a collection of various individual networks
connected by intermediate networking devices. The inter-
network function as a single large network.
The internet is defined as a vast inter connected network of
computer networks, where world wide information resources
can be shared through the World Wide Web.
INTRODUCTION TO INTERNET

18. World Wide Web
The concept of WWW was developed at
CERN (Centre European de Researchers
Nucleaire) that is Centre European particle
physics laboratory in 1992 by the group of
researchers including Team Berners Lee.
The internet is an inter connection of
large number of computers, but it is very
difficult to get all the information available
on the internet. Therefore a user interface
called WWW was developed.

19. E-Commerce
Electronic commerce is considered
to be a subset of e-business. It is
defined as dealing with buying and
selling of services and product over
electronic system such as the
internet.
The customers need not go to the
market for shopping; rather they
can place their orders online.

20. E-Commerce can be categorized into several types –
 Business to Business(B2B)
 Business to Consumer(B2C)
 Consumer to Business(C2B)
 Consumer to Consumer(C2C)
E
COMMERCE
B2B
C2B
C2C
B2C