Computer Networks and Internet Basics: Computer Networks: Introduction to networks, types of networks (LAN, WAN, WLAN), network topologies. Networking Basics: Network components (routers, switches, hubs), IP addressing (IPv4, IPv6), TCP/IP Protocol. Internet and World Wide Web: Understanding the Internet, web browsers, search engines, online research techniques.

1. COMPUTER APPLICATIONS
Dr. Arti Parab
School of Allied Healthcare & Sciences, Jain Deemed-to-be University, Bangalore

2. CONTENTS: MODULE 3
• Computer Networks and Internet Basics:
• Computer Networks:
• Introduction to networks, types of networks (LAN, WAN, WLAN), network
topologies.
• Networking Basics:
• Network components (routers, switches, hubs), IP addressing (IPv4, IPv6),
TCP/IP Protocol.
• Internet and World Wide Web:
• Understanding the Internet, web browsers, search engines, online research
techniques.

3. COMPUTER NETWORKS
• Introduction to networks
• Types of networks (LAN, WAN, WLAN)
• Network topologies

4. What is a computer Network?

5. • A computer network is a collection of
interconnected devices, such as
computers, servers, routers,
switches, and other networking
hardware, that are linked together to
facilitate communication and data
sharing.
• It allows these devices to exchange
data, resources, and information with
each other, enabling efficient
communication and collaboration.
• A computer network can be as small
as two devices connected together or
as large as a global network that
spans across different geographic
locations. Networks can be classified
into different types based on their
size, scope, and purpose.

6. What are the different types of Computer Networks?

7.  Personal Area Network (PAN)
 As the most basic type of network, a PAN consists of a wireless modem, one or two computers, mobile phones,
printers, tablets, etc. These types of networks are usually found in small offices or residences and are managed
from a single device by one person or organization. It can also be used to communicate between personal
devices to connect to a digital network and the Internet itself.
 Local Area Network (LAN)
 LAN connect a number of computers and low- voltage devices over short distances (in a building or in close
proximity between two or three buildings) to share information and resources. Companies normally manage and
maintain LAN. All machines on LAN are connected to one cable. Usually, it is a private network. LAN can connect
to wide area networks (WANs) with routers to transmit data quickly and safely.
 Wide Area Network (WAN)
 The WAN connects large number of computers spreading across a long geographical distance. This allows
computers and low- voltage devices to communicate remotely over a large network. Due to WAN’s capacity of
wide reaching; it is usually owned and maintained by several administrators or the public. The majority of WAN
networks are used to transmit large data blocks between their users.
 Metropolitan Area Network (MAN)
 These network types are larger than LANs but smaller than WANs– and include elements of both network types.
MANs cover a whole geographical area (typically a city or town, but sometimes a campus). Ownership and
maintenance are carried out by one person or company (local council, large company, etc.).
 Campus Area Network (CAN)
 Campus area network consists of a LAN connection with a limited geographical area. Network devices such as
switches, routers, optical fiber etc. are entirely owned by the campus network owner. Typically, these types of
networks are seen in universities, large K-12 school districts or small companies. They can be spread over
several buildings which are relatively close together so that users can share resources.

8. 5 COMMON TYPES OF COMPUTER NETWORKING
Computer networks have
some common
applications –
•Share available hardware
resources
•Share software and
database
•Establish communication
among connected
computers
•Exchange of data and
information
•Share information over
geographically wide areas

9. What is Network Topology?

10. • Network topology refers to the
physical or logical arrangement
of devices in a computer
network. It defines how devices,
such as computers, servers,
routers, switches, and other
network components, are
connected to each other and
how data flows between them.
• Network topology describes the
structure of the network and the
pattern of communication
among devices.

11. TYPES OF NETWORK TOPOLOGY

12. TYPES OF NETWORK TOPOLOGY
1. Bus network topology -- Also known as backbone network topology, this configuration connects all
devices to a main cable via drop lines. The advantages of bus network topology lie in its simplicity, as there
is less cable required than in alternative topologies, which makes for easy installation.
2. Mesh network topology -- A dedicated point-to-point link connects each device on the network to
another device on the network, only carrying data between two devices.
3. Ring network topology -- Two dedicated point-to-point links connect a device to the two devices located
on either side of it, creating a ring of devices through which data is forwarded via repeaters until it reaches
the target device.
4. Star network topology -- The most common network topology, star topology connects each device in the
network to a central hub. Devices can only communicate with each other indirectly through the central hub.
5. Hybrid network topology -- Any combination of two or more topologies is a hybrid topology.
6. Tree network topology -- This topology consists of a parent-child hierarchy in which star networks are
interconnected via bus networks. Nodes branch out linearly from one root node, and two connected nodes
only share one mutual connection.

13. FAQS
• Question 1. Which network covers the largest geographical area?
• a) LAN
• b) WAN
• c) MAN
• d) PAN
Answer: b) WAN (Wide Area Network)

14. FAQS
• Question 2. Which network topology uses a central hub to connect all devices?
• a) Star topology
• b) Bus topology
• c) Ring topology
• d) Mesh topology
Answer: a) Star topology

15. FAQS
• Question 3. In which network topology, each device is connected to exactly two other
devices, forming a closed loop?
• a) Star topology
• b) Bus topology
• c) Ring topology
• d) Mesh topology
Answer: c) Ring topology

16. FAQS
• Question 4. Which network topology uses a single communication line where all devices
share the same connection?
• a) Star topology
• b) Bus topology
• c) Ring topology
• d) Mesh topology
Answer: b) Bus topology

17. FAQS
• Question 5. In which network topology, every device has a direct connection to every
other device?
• a) Star topology
• b) Bus topology
• c) Ring topology
• d) Mesh topology
Answer: d) Mesh topology

18. NETWORKING BASICS
• Network components (routers, switches, hubs, etc.)
• IP addressing (IPv4, IPv6)
• TCP/IP Protocol

19. NETWORK COMPONENTS
• Network
components play a
crucial role in the
functioning and
management of
computer networks.
They include routers,
switches, hubs,
modems, network
interface cards
(NICs), and network
cables.

20. NETWORK COMPONENTS
• Routers: Routers are devices that help connect different networks together. They act like traffic controllers, directing
data to the right destination. Think of them as the GPS system for data, guiding it through the network highways to reach
its intended location.
• Switches: Switches are devices that connect multiple devices within a local network, such as computers, printers, and
servers. They are like the central hub of a network, ensuring that data gets delivered to the right device. Imagine switches
as efficient postal workers who sort and deliver packages to the correct addresses within a neighborhood.
• Hubs: Hubs are similar to switches, but they are not as smart. They are like a broadcasting station that sends data to all
connected devices, without considering who the data is meant for. This can lead to congestion and slower network
performance, so hubs are not commonly used in modern networks.
• Modems: Modems are devices that connect your computer network to the internet. They take the digital data from your
network and convert it into signals that can be transmitted over telephone lines or other communication mediums.
Modems are like the gateway to the internet, allowing your network to access online resources.
• Network Interface Cards (NICs): Network Interface Cards are the components that enable devices, such as computers
or laptops, to connect to a network. They are like the entry points or plugs that allow devices to join the network and
communicate with other devices. NICs come built-in with most devices or can be added as an expansion card.
• Network Cables: Network cables are physical cables that connect devices within a network. They are the wires that
carry data signals from one device to another. Ethernet cables, similar to the cables used for internet connections at
home, are commonly used in networks. Think of network cables as the roads that enable communication between
devices in a network.

21. IP ADDRESSING
• IP addressing, short for Internet Protocol
addressing, is a system used to identify and
locate devices on a network. It provides a unique
numerical label to each device connected to a
network, allowing them to communicate with
each other using the Internet Protocol (IP).
• IP addresses consist of a series of numbers
separated by periods. In the most common form,
known as IPv4 (Internet Protocol version 4), IP
addresses are represented by four sets of
numbers ranging from 0 to 255. For example, an
IPv4 address could look like 192.168.0.1.

22. TECHNICAL FACTS ABOUT AN IP ADDRESS
• An IP address is a 32-bit binary number that is
divided into four sections by periods
• Each individual set of numbers in an IP address
is called an octet
• There are four octets in an IP address and each
octet is 8 bits
• An octet can range from 0 to 255 in value. (255
is the largest number that you can represent
with 8 bits)
The IP address serves two main purposes:
 Device Identification: Each device connected to a network,
whether it's a computer, smartphone, or any other
network-enabled device, is assigned a unique IP address.
This address acts as a digital identifier for the device,
allowing it to send and receive data across the network.
 Routing: IP addresses are used for routing data packets
across networks. When data is transmitted from one device
to another, it is broken down into smaller packets. Each
packet carries the source IP address (the address of the
sending device) and the destination IP address (the address
of the receiving device). Routers on the network use the
destination IP address to determine the most efficient path
for the data packets to reach their destination.

23. What is IPv4 and IPv6?

24. IPV4 AND IPV6
• IPv4 (Internet Protocol version 4):
• Imagine the internet as a vast neighborhood with millions of houses. In order for different devices (like computers,
smartphones, and tablets) to communicate and send data to each other within this neighborhood, they need unique
addresses, just like houses have unique street addresses.
• IPv4 is like an older system of house addresses with a limited number of unique addresses available. It uses a series of four
numbers separated by dots, such as 192.168.1.1. However, with the rapid growth of the internet and the increasing number
of devices, the available IPv4 addresses have become scarce, similar to running out of house addresses in a crowded
neighborhood.
• IPv6 (Internet Protocol version 6):
• To address the shortage of unique addresses in IPv4, a new system called IPv6 was introduced. Think of IPv6 as an expanded
and more advanced address system for the internet neighborhood. Instead of four numbers, IPv6 uses eight groups of four
characters, such as 2001:0db8:85a3:0000:0000:8a2e:0370:7334.
• With IPv6, there are so many unique addresses available that it's like having an almost infinite number of houses in the
neighborhood. This means that as more and more devices join the internet, they can all have their own unique address,
allowing for seamless communication and connection across the entire internet community.

25. TCP/IP PROTOCOL
• TCP/IP (Transmission Control
Protocol/Internet Protocol) is
like a set of rules or a language
that computers use to talk to
each other over the internet.
Imagine it as a communication
system that allows devices, like
computers, smartphones, and
tablets, to understand each
other and exchange
information smoothly.

26. TCP/IP PROTOCOL
• Transmission Control Protocol (TCP): Think of TCP as a reliable messenger. When you want to send a message
(data) from your computer to another computer over the internet, TCP makes sure that the message is delivered
accurately. It breaks the message into smaller packets, sends them one by one, and makes sure they arrive in the
correct order. If a packet gets lost or corrupted during the journey, TCP will request a re-send to ensure that the
entire message is received correctly.
• Internet Protocol (IP): IP is like a postman delivering letters to the right addresses. It assigns a unique address to
each device connected to the internet, just like your home has a unique address. This address is called an IP
address (e.g., 192.168.1.1 for IPv4 or 2001:0db8:85a3:0000:0000:8a2e:0370:7334 for IPv6). When you send a
message, IP uses the destination IP address to find the correct computer and deliver the data packets to the right
place.
• Combining TCP and IP: Together, TCP and IP work hand in hand. TCP ensures that your message is sent reliably
and without errors, while IP ensures that the message reaches the right destination. It's like a team of messengers
who make sure your data is sent correctly and safely to its intended recipient over the vast internet network.

27. FAQS
• Question 1. Which version of IP addressing is a 32-bit address represented in decimal
format (e.g., 192.168.1.1)?
• a) IPv1
• b) IPv4
• c) IPv6
• d) IPv8
Answer: b) IPv4

28. FAQS
• Question 2. Which protocol is responsible for establishing and maintaining a reliable
connection between two devices for data transmission?
• a) TCP
• b) IP
• c) HTTP
• d) FTP
Answer: a) TCP

29. INTERNET AND WORLD WIDE WEB
• Understanding the Internet
• Web browsers
• Search engines
• Online research techniques

30. UNDERSTANDING THE INTERNET
• Internet is a global network that connects
billions of computers across the world with
each other and to the World Wide Web. It
uses standard internet protocol suite
(TCP/IP) to connect billions of computer
users worldwide.
• It is set up by using cables such as optical
fibers and other wireless and networking
technologies. At present, internet is the
fastest mean of sending or exchanging
information and data between computers
across the world.
https://youtu.be/utMtkV-Mf3Y

31. HOW DOES INTERNET WORK?
 The internet works with the help of clients and servers.
 A device such as a laptop, which is connected to the internet is called a client.
 However, it is indirectly connected to the internet through an Internet Service Provider (ISP) and is identified by
an IP address, which is a string of numbers.
 Just like you have an address for your home that uniquely identifies your home, an IP address acts as the shipping
address of your device.
 The IP address is provided by your ISP, and you can see what IP address your ISP has given to your system.
 A server is a large computer that stores websites. It also has an IP address.
 A place where a large number of servers are stored is called a data center.
 The server accepts requests send by the client through a browser over a network (internet) and responds
accordingly.
 To access the internet we need a domain name, which represents an IP address number, i.e., each IP address has
been assigned a domain name. For example, youtube.com, facebook.com are used to represent the IP addresses.

32. WEB BROWSERS
Web Browser (or Internet Browser) is an application that supports
the client-side of the Hypertext Transfer Protocol (HTTP), the
Internet protocol for the World Wide Web (WWW). You can use a
Web browser, also called a “browser,” to access (browse) content
published on a Web server. Each individual web page, image, and
video is identified by a distinct Uniform Resource Locator (URL)
enabling browsers to retrieve these resources from a web server and
display them on a user’s device.
What “web browsers” are the
most used by Internet users?
Web Browser Market Share
Chrome 71.05%
Firefox 9.52%
Safari 5.41%
Internet
Explorer
5.41%
Edge 4.60%
Other 4.43%

33. SEARCH ENGINES
• By typing a simple query into the search box,
a search engine can return a vast amount of
results within a few milliseconds.
• A search engine consists of two main
components, a database of indexed links and
files, and a series of algorithms that search for
and return query results.
• Google’s search engine is the most widely
used in the world; its database consists of
many trillions of links to web pages and its
algorithms takes hundreds of factors into
account to calculate the most relevant search
results.

34. HOW DO SEARCH ENGINES WORK?
• The search engine’s algorithms control three main
functions, web crawling, indexing and ranking.
• Search engines send out web crawlers locate and review
website content. This content is reviewed regularly for any
new changes, and also to determine the type of data
displayed on the websites.
• A scheduler maintains how often the websites will be
reviewed for new updates. Important information from
the websites is extracted and parsed, the scheduler
determines, using a number of different factors, how
often a website needs to be reviewed and crawled again.
• Once a website has been reviewed or ‘crawled’ it is
indexed on the search engine’s database. During the
indexing process, the search engine will use various
factors to determine how and where a particular web
page may be displayed with regards to an end user’s
search query.
https://www.javatpoint.com/top-10-search-engines

35. HOW DO SEARCH ENGINES WORK?
• Scheduler
• The search engine’s scheduler assesses the relative importance of new and already reviewed URLs. It then uses
various algorithms to decide when to crawl new URLs and how often to re-crawl known URLs, depending on their
perceived importance.
• Web Crawling
• Web crawlers are automated software programs that search the internet for new website URLs to analyze the content
contained on the pages.
• Parsing
• The parser extracts links from the page, along with other key information such as content type. It then sends the
reviewed URLs to the stored and the extracted data for indexing.
• Indexing
• Indexing is defined as the process of where parsed information from crawled pages is added to an indexed database.
The database can be compared to a vast digital library of many trillions of web pages.

36. HOW DO GOOGLE’S RANKING ALGORITHMS WORK?
• Google is well known for the secrecy regarding the exact details of their search engine operations, and
undoubtedly there are many complicated algorithms being used, but there are important factors that have
been made known.
• Topical Relevance
• Search Intent
• Freshness
• Content Quality
• Page Loading Speed
• Mobile-Friendliness
• Personalization

37. ONLINE RESEARCH TECHNIQUES
• Online research is a research method that involves the
collection of information from the internet. With the
advent of the internet, the traditional pen-and-paper
research techniques have taken a backseat and made
room for online research design.
• Online surveys, online polls, questionnaires, forms, and
focus groups are various tools of online research that are
vital in gathering essential information for market
research.
• Online research can be carried out for product testing,
targeting an audience, database mining, customer
satisfaction etc.
https://www.questionpro.com/blog/execute-online-
research/

38. 5 ONLINE RESEARCH METHODS AND TECHNIQUES
• Online focus group: A subset of the online research techniques, online focus groups are methods
usually used for B2B research, consumer research and political research. A moderator is assigned to
conduct and supervise the focus group who invites pre-selected and qualified participants who
represent a specific area of interest to be a part of this focus group at a particular time. The
respondents are usually incentivized to be a part of the discussion, which usually is an hour and 90
minutes.

39. 5 ONLINE RESEARCH METHODS AND TECHNIQUES
• Online interview: This online research method is quite similar to the face-to-face interview methods
yet different in terms of the required standard practices, understanding with respondents, and
sampling. Online interviews are organized using various computer-mediated communication (CMC),
essentially SMS or Email. Based on the response time for these interviews, they’re classified into
synchronous and asynchronous methods. Synchronous online interviews are carried out via mediums
such as online chat, where the responses are received in real-time. Asynchronous online interviews are
those that happen over Email, where the responses are usually not in real-time. Just like face-to-face
interviews, online interviews probe into respondents’ thoughts and feedback about a particular topic to
get insights into their experiences, ideas, or attitudes.

40. 5 ONLINE RESEARCH METHODS AND TECHNIQUES
• Online qualitative research: Other than the mainstream online focus groups and online interviews,
there are various aspects of online qualitative research. These aspects include blogs, mobile diaries, and
communities. These methods contribute toward cost and time savings and are supremely convenient
for the researchers to gather information for their research topics. The level of sophistication that
online qualitative research methods bring to the table is superior to any other traditional forms as the
respondents can be either recruited from existing databases, or panels or can be added by conducting
surveys.

41. 5 ONLINE RESEARCH METHODS AND TECHNIQUES
• Online text analysis: This analysis technique is an extension of text analysis which exists since the
17th century which is a collection of various online research examples used to derive insights from
content available online. By using this online research technique, researchers can explain penned,
verbal or graphic communication formats. Categories such as web pages, paragraphs, sentences, quasi-
sentences, documents, etc. It is most often used for quantitative research but for better interpretation
of the text, researchers also use qualitative techniques.

42. 5 ONLINE RESEARCH METHODS AND TECHNIQUES
• Social network analysis: Social network analysis is an emerging online research technique which is
gaining acceptance due to the increased adoption of social networking platforms. By conducting social
network analysis, a researcher can map and measure flows and relationships between people,
organizations, URLs, groups or computers using graph theory. For instance, the latest meme culture has
developed new social structures in which the people associated are termed as “nodes” and memes are
the “links” between these nodes.

43. THANK YOU!