The document discusses key concepts related to how the internet works. It defines the internet as a global network of interconnected computer networks that uses TCP/IP to serve billions of users. It describes the client/server model where clients access web servers to retrieve web pages, images, and files. It also explains important protocols like HTTP and HTML that allow communication and formatting of web pages, and concepts like IP addresses, MAC addresses, and cookies that enable identification and functionality on the internet.

1. Computer Science 2210
Internet Principles of
Operation
By Inqilab Ruknuddin Patel
inqilab@ruknuddin.com
www.ruknuddin.com

2. Objectives:
•show understanding of the role of the browser and
Internet server
•show understanding of what is meant by hypertext
transfer protocol (http) and HTML
•distinguish between HTML structure and
presentation
•show understanding of the concept of MAC
address, Internet Protocol (IP) address and cookies

3. What is Internet?
The Internet is a global system of interconnected computer
networks that use the standard Internet protocol suite to
serve billions of users worldwide.
It is a network of networks that consists of millions of
private, public, academic, business, and government
networks, of local to global scope, that are linked by a broad
array of electronic, wireless and optical networking
technologies.
Internet carries an extensive range of information resources
and services, such as the inter-linked hypertext documents
of the World Wide Web (WWW) and the infrastructure to
support email.

4. Client/Server Architecture
A network architecture in which each computer or process
on the network is either a client or a server.
Internet server (web server) is a special computer, on which
websites are stored. Web Server is constantly switched on
and connected to the Internet so that each Internet user
around the world can access website at all times. This
computer is built up with selected high quality components,
which can endure incessant work and high load.
Clients are PCs or workstations on which users run
applications.

5. Client/Server Architecture

6. Web Client
Web client is a computer, on which user actually
works. It has web browser to locate, retrieve and
display contents on web servers.
The user logs onto a client computer which then
connects to the server, verifies the user and then
allows them access to the files stored on the server
that they have permission to access.

7. Web Browser
Web browser is a software application used to
locate, retrieve and also display content on the
World Wide Web, including Web pages, images,
video and other files.
The major web browsers are Firefox, Google
Chrome, Internet Explorer, Opera, and Safari

8. Web Server
Web server is a special computer, on which
websites are stored.
Web Server is constantly switched on and
connected to the Internet so that each Internet
user around the world can access website at all
times.
This computer stores:
Websites
Images & Videos
Files

9. HTML
HTML is the "mother tongue" of your browser.
HTML (Hyper Text Mark-up Language) is the
authoring language, used to create web pages and
other information that can be displayed in a web
browser.
The websites are developed in HTML and stored on
Web Servers. When User types the URL of website,
browser locates and fetches the website from
server on clients computer and displays contents.

10. HTTP
HTTP (HyperText Transfer Protocol), the underlying
protocol used by the World Wide Web. HTTP
defines how messages are formatted and
transmitted, and what actions Web servers and
browsers should take in response to various
commands. For example, when you enter a URL in
your browser, this actually sends an HTTP command
to the Web server directing it to fetch and transmit
the requested Web page.

11. Protocols
A protocol is the set of rules that define how
devices communicate.
how the communication will start
the transmission speed
the significance of the bits being transmitted
how the bits will be delivered (one at a time or in
groups of 16 for example)
error checking procedures used
The Internet Protocol is known as TCP/IP.

12. IP Addressing
An Internet Protocol (IP) address is a unique 32-bit reference number
that is allocated to devices on a computer network that uses the
Internet Protocol.
IP addresses are stored as 32-bit numbers
2^(32) = 4 billion possible unique IP addresses
For our convenience IP addresses are usually displayed as a series of 4
decimal numbers, each one representing 8 bits of the original binary
address.
32-bit binary version: 110010011010000001011011011111111
11001001  201
10100000  160
01011011  91
01111111  127
decimal version: 201.160.91.127
Some IP addresses are reserved for private network ranges e.g.
10.0.0.0 - 10.255.255.255
172.16.0.0 - 172.31.255.255
192.168.0.0 - 192.168.255.255

13. MAC Addressing
In computer networking, a Media Access Control address
(MAC address) is a unique 48-bit number assigned to a
network interface card (NIC) to identify it on a LAN. Because
they are so long, MAC addresses are usually displayed in
hexadecimal.
48-bit binary version:
000000000000100101111100111100011111011110000101
hexadecimal version: 00-09-7C-F1-F7-85
MAC addresses are stored as 48-bit numbers
2^(48) = 281 trillion possible unique MAC addresses.

14. Cookies
(HTTP cookie, web cookie, or browser cookie)
A cookie is a small piece of data sent from a
website and stored in a user's web browser while
the user is browsing that website. Every time the
user loads the website, the browser sends the
cookie back to the server to notify the website of
the user's previous activity In computer networking.

15. Thank you
By Inqilab Ruknuddin Patel
inqilab@ruknuddin.com
www.ruknuddin.com