The document provides an overview of the history and components of the Internet. It discusses how the Internet began as a US Department of Defense project called ARPANET in the 1960s and has since evolved to become a global network connecting billions of devices. It describes the various protocols used to communicate over the Internet like TCP/IP as well as common applications and services available online like email, the World Wide Web, streaming media, and social networks. It also provides details on how data is transmitted at each layer of the OSI reference model.

2. INTERNET
Internet or internetworking refers to a wide
network through which computers are interconnected
globally with one another, capable of sharing
resources among themselves. This network is called
‘internet’. Internet refers to millions of computers,
connected in a gigantic network, which communicate
via TCP/IP protocols.

3. It is a network of networks. Internet carries an
extensive range of information resources and services,
such as the inter-linked hypertext documents
and applications of the World Wide Web (WWW),
electronic mail, telephony, and peer-to-peer
networks for file sharing.

4. HISTORY OF INTERNET
1950S - electronic computers.
 Packet networking -computer science laboratories
in the United States, United Kingdom, and France.
 1960s -US Department of Defense developed
the ARPANET
1961s - Wesley Clark- Interface Message Processor
computer interface between computer and WAN
 1972 - Bob Kahn – Packet switched network
1973s -TCP/IP
 1980 - Ethernet

5. 1982 - Simple Mail Transfer Protocol
 1983 - Domain Name System
 1985 – First .Com domain name registered
 1988 - OSI Reference Model released
 1990 - Search engine
 1991 - WWW
 1995 – Amazon
 1996 – Hotmail
 1998- Google search
 2001- Wikipedia
 2003- Skype

6. 2004- Facebook
2005- Youtube
2006 - Twitter
2007- Kindle
2009- Bing
2010- Instagram

7. SERVICES AND ACCESSIBILITY
Electronic mail
Electronic mailing lists
USENET newsgroups
Real-time communication
File transfer protocol
Telnet
Gopher
World Wide Web (WWW)

8. INTERNET CONNECTIONS
Dial-up connections
High Speed Connections
–Digital Subscriber Lines (DSL)
–Cable
–Satellite
–Integrated Services Digital Network (ISDN)

9. TYPES OF NETWORK
Example Range Bandwidth
(Mbps)
Latency
(ms)
Wired:
LAN Ethernet 1-2 km 10-1000 1-10
MAN ATM 250 km 1-150 10
WAN IP routing worldwide .01-600 100-500
Internetwork Internet worldwide 0.5-600 100-500
Wireless:
WPAN Bluetooth (802.15.1) 10 - 30m 0.5-2 5-20
WLAN WiFi (IEEE 802.11) 0.15-1.5 km 2-54 5-20
WMAN WiMAX (802.16) 550 km 1.5-20 5-20
WWAN GSM, 3G phone nets worldwide 0.01-2 100-500

10. USES OF THE INTERNET
 Telecommuting
 News, jobs, software
Online courses, virtual classrooms, coaching
Government services, politics and national
defense
Electronic publishing
Entertainment
Teaching and learning
Scholarly research

11. BENEFITS OF USING INTERNET
 Global Audience
 Operates 24 hours, 7 days a week
 Relatively Inexpensive
 Product Advertising
 Distribute Product Catalogs
 Online Surveys
 Announcements
 Obtain Customer Feedback
 Immediate Distribution of Information
 Multimedia

12. DISADVANTAGES OF THE INTERNET
 Spam Mail
 Kids Exposed to Adults-Only Content
 Addiction to Internet
 Leakage of Private Information
 Virus, Trojan and Other Malware

13. WEB CONCEPT
 WWW – hypertext – millions of documents
 hypertext link
 Web page- HTML
Website- related pages
 Web server
 Web Browser

14. WORKING Of CLIENT /SERVER MODEL
 Client
 Server
http
 URL – Uniform Resource Locator
Protocol
 Domain Name
Path
http: //www.vvvc.org/students.html
 Host names
.edu .com .org .gov

15. PROTOCOLS
Set of rules or an agreement
 Ethernet
 Internet Protocol
 Transport Control Protocol
 File transport Protocol
 Hypertext Transport Protocol
 Simple Mail Transfer Protocol

16. INTERNET PROTOCOL
IP Address
Network Address – 128.213
Host Address – 1.1
Types of Internet Protocol
7 24
Class A: 0 Network ID Host ID
14 16
Class B: 1 0 Network ID Host ID
21 8
Class C: 1 1 0 Network ID Host ID
28
Class D (multicast): 1 1 1 0 Multicast address
27
Class E (reserved): 1 1 1 1 unused0

17. TRANSMISSION CONTROL PROTOCOL
 OSI reference model
 Reliable transmission, Connection oriented
 Application to IP layer
 Detect lost packets
 Request for retransmission
USER DATAGRAM PROTOCOL
 Connectionless
 no reliability
 Source port, Destination port, Length and
checksum.

18. OVERVIEW OF OSI REFERENCE MODEL
 Open Systems Interconnection
 Created by International
Standards Organisation
 Seven Layer model
 Relationship and interaction
between network services
 Rules and conventions for
various functions within
each layer

20. PHYSICAL LAYER
Deals with all aspects of physically moving data
from one computer to the next
Cable standards, wireless standards, and fiber optic
standards
Used to transmit data
Hub
DATA LINK LAYER
Is responsible for moving frames from node to node
or computer to computer across routers
Ethernet Protocol and Point-to-Point Protocol (PPP)

21.  Switch
Two sub layers: Logical Link Control (LLC) and
the Media Access Control (MAC)

22. Logical Link Control (LLC)
Data Link layer addressing, flow control, address
notification, error correction
Media Access Control (MAC)
Determines which computer has access to the
network media at any given time
Determines where one frame ends and the next one
starts called frame synchronization

23. Network Layer
Responsible for moving packets (data) from one
end of the network to the other, called end-to-end
communications
logical addresses such as IP addresses
Router
Routing is the ability of various network devices
and their related software to move data packets
from source to destination

24. TRANSPORT LAYER
Data transmission
Reassembled in correct order at destination
connection-oriented protocol
connectionless protocol
Reliability of the transport of sent data
SESSION LAYER
Managing the dialog between networked devices
Establishes, manages, and terminates connections
Provides procedures for establishing checkpoints,
adjournment, termination, and restart or recovery
procedures

25. PRESENTATION LAYER
How data is presented to the network
Handles three primary tasks:
Translation
Changes data so another type of computer can
understand it.
Compression
Makes data smaller to send more data in same
amount of time.
Encryption
Encodes data to protect from interception or
eavesdropping.

26. APPLICATION LAYER
Contains all services or protocols needed by
application software or operating system to
communicate on the network
Firefox web browser uses HTTP
E-mail program may use POP3 to read e-mails and
SMTP to send e-mails

28. Thank you