The document provides an overview of internet fundamentals and applications. It discusses the history of the internet and intranets, and how internet protocols like TCP/IP allow different networks to connect. It also describes common internet elements like clients, servers, internet service providers (ISPs), IP addresses, and the domain name system (DNS). The document is intended as an introduction to fundamental internet concepts.

1. INTERNET FUNDAMENTAL
AND AppLICATIONS
Ashish Gautam
Principal Software Engineer

2. 1. Introduction
a. Introduction: Internet; Intranet; Extranet
b. History: Internet; Intranet; Extranet
c. Internetworking Protocol: Introduction to TCP/IP. The Internet
Architecture: Client, ISP, Regional ISP, and Backbone.
d. Managing the Internet: Governing bodies of the Internet.
e. Connecting to Internet: How to connect to the Internet?
f. Internet Connections: Different internet connections.
g. Internet Address: IP address and domain names.
h. Internet Services: WWW, Email, FTP, Telnet.
i. Uses of Internet: Different uses of Internet.

3. Introduction: Internet
● Its Global Network of Computers ( Client and Server ), to exchange information.
● It is a Global network of computers, (servers or clients). to exchange information. It is a "network
of networks" that includes millions of private and public, academic, business, and government
networks (local or Global), linked by copper wires, wireless connections, and other technologies.
● The Internet is a vast network that connects computers all over the world. Through the Internet,
people can share information and communicate from anywhere with an Internet connection.

4. Intranet
● Internal company network that uses Internet standards (HTML, HTTP & TCP/IP protocols) &
software.
● Accessed only by authorized persons, especially members or employees of the organization
● An intranet is a private enterprise network, designed to support an organization’s employees to
communicate, collaborate and perform their roles. It serves a broad range of purposes and uses,
but at its core, an intranet is there to help employees.

5. Extranet
● Extranet is an Intranet for outside authorized users using same internet technology. Inter-
organizational information system.
● enable outsiders to work together with company’s employees.
● open to selected suppliers, customers & other business partners
● Example: Dealers/distributors have access to product files such as :- 1. product specification, 2.
pictures, 3. images, etc. to answer the queries of the customer.

6. History of Internet
● In 1962, a scientist from M.I.T. and DARPA named J.C.R. Licklider proposed : a “galactic network” of computers that could
talk to one another. Such a network would enable government leaders to communicate even if the Soviets destroyed the
telephone system.
● In 1965, another M.I.T. scientist developed a way of sending information from one computer to another that he called
“packet switching.” Packet switching breaks data down into blocks, or packets, before sending it to its destination.
● Without packet switching, the government’s computer network—now known as the ARPANET—would have been just as
vulnerable to enemy attacks as the phone system.
● In 1969, ARPANET delivered its first message: a “node-to-node” communication from one
● By the end of 1969, just four computers were connected to the ARPANET, but the network grew steadily during the 1970s.
● As packet-switched computer networks multiplied, however, it became more difficult for them to integrate into a single
worldwide “Internet.”
● By the end of the 1970s, a computer scientist named Vinton Cerf had begun to solve this problem by developing a way for
all of the computers on all of the world’s mini-networks to communicate with one another.
● He called his invention “Transmission Control Protocol,” or TCP. (Later, he added an additional protocol, known as
“Internet Protocol.” The acronym we use to refer to these today is TCP/IP.)
● TCP/IP was described to be the “handshake” between computers all over the world. It enabled each computer to have its
own identity.

7. ● Internet in the 1980’s Cerf’s protocol transformed the Internet into a worldwide network.
Throughout the 1980s, researchers and scientists used it to send files and data from one computer
to another. However, this network was still between scientists and researchers from different
universities and labs.
● Internet in the 1990’s However, in 1991 the Internet changed again. Tim Berners-Lee introduced
the World Wide Web: an Internet that was not simply a way to send files from one place to
another but was itself a “web” of information that anyone on the Internet could retrieve. Berners-
Lee created the first browser and the Internet that we know today.
● In 1992, a group of students and researchers at the University of Illinois developed a sophisticated
browser that they called Mosaic. (It later became Netscape.) Mosaic offered a user-friendly way to
search the Web: It allowed users to see words and pictures on the same page for the first time and
to navigate using scrollbars and clickable links.
● That same year, Congress decided that the Web could be used for commercial purposes. As a
result, companies of all kinds hurried to set up websites of their own, and e-commerce
entrepreneurs began to use the Internet to sell goods directly to customers. More recently, social
networking sites like Facebook have become a popular way for people of all ages to stay
connected.

8. History Of Intranet
1990s: The World Wide Web explodes into wide commercial use. This period also makes the
earliest appearance of the intranet, traditionally as a singular welcome page with essential, basic
company information. Flat, text-heavy with the traditional blue hyperlinks, they served to deliver
basic company communications before developing to a clunky document management system
(DMS) by the mid-late 1990s.

9. 2000s: Technology was developing, and the intranets followed suit. Help desk features were
introduced, enabling users to perform transactional processes such as finding colleagues on the
employee directory, performing basic HR functions such as booking absences or searching for
information.
Platforms began to integrate the company brand and identity with content and applications
designed to support employees in their day-to-day roles. While still heavily weighted as a company
information tool, intranets could deploy better search features, allowing employees to access the
information they needed quickly and effectively.

10. 2010s: Entering the public domain is the phenomenon that became social media. Recognizing the
value of these tools, many intranets began to follow suit and integrate basic social functions
including limited blogging tools, wikis and discussion forums. Now, the intranet was no longer
about one-way communication from the top down: it was a place for conversations.
Intranets also swept up developments in document management, offering better access to
centralized information. Communities began to appear, as early forms of collaboration emerged.
Forms also saw improvements, meaning intranets could serve a cross-functional role in business:
helping employees to self-serve and making some basic, common workflows more efficient.

11. Recent years: Sweeping up developments in social media, intranets now give precedence to user
profiles and incorporate an array of social features, such as @mentioning, #tagging,
microblogging or commenting. Activity streams provide real-time insights and information, while
increasingly sophisticated algorithms and data analytics allow for greater personalization, pushing
recommended content to users.
User experience is given greater focus and investment, with developments in design, accessibility,
performance and user journeys. Integration functionality is now common, with intranets designed
to work in partnership with other applications.
Intranets, as we know and recognize them today, are far removed from the earliest versions in the
corporate market and show great flexibility to evolve and change with wider technological trends.

12. History of Extranet
During the late 1990s and early 2000s, several industries started to use the term 'extranet' to describe
centralized repositories of shared data (and supporting applications) made accessible via the web only to
authorized members of particular work groups - for example, geographically dispersed, multi-company
project teams. Some applications are offered on a software as a service (SaaS) basis.
For example, in the construction industry, project teams may access a project extranet to share drawings,
photographs and documents, and use online applications to mark-up and make comments and to manage
and report on project-related communications. In 2003 in the United Kingdom, several of the leading
vendors formed the Network for Construction Collaboration Technology Providers (NCCTP) to promote
the technologies and to establish data exchange standards between the different data systems. The same
type of construction-focused technologies have also been developed in the United States, Australia and
mainland Europe.

13. Internetworking Protocol
Internetworking is the practice of interconnecting multiple computer networks, such that any pair
of hosts in the connected networks can exchange messages irrespective of their hardware-level
networking technology. The resulting system of interconnected networks are called an
internetwork, or simply an internet.
The most notable example of internetworking is the Internet, a network of networks based on
many underlying hardware technologies. The Internet is defined by a unified global addressing
system, packet format, and routing methods provided by the Internet Protocol

14. Introduction to TCP/IP
Just like people, it’s important for computers to have a common way to communicate with each other. Today most
computers do this through TCP/IP. TCP/IP is typically built into computers and is largely automated, but it can be useful
to understand the TCP/IP model, particularly when you’re setting up a computer to connect with other systems
TCP/IP (Transmission Control Protocol/Internet Protocol) is a set of protocols independent of the physical medium used
to transmit data, but most data transmission for Internet communication begins and ends with Ethernet frames.
TCP/IP was developed by the U.S. Department of Defense to specify how computers transfer data from one device to
another. TCP/IP puts a lot of emphasis on accuracy, and it has several steps to ensure that data is correctly transmitted
between the two computers.

15. The four layers of the TCP/IP model
TCP/IP is a datalink protocol that is used on the internet. Its model is split into four distinct layers. Used together,
they can also be referred to as a suite of protocols.
Datalink layer
The datalink layer (also called the link layer, network interface layer, or physical layer) is what handles the physical
parts of sending and receiving data using the Ethernet cable, wireless network, network interface card, device
driver in the computer, and so on.
Internet layer
The internet layer (also called the network layer) controls the movement of packets around the network.
Transport layer
The transport layer is what provides a reliable data connection between two devices. It divides the data in
packets, acknowledges the packets that it has received from the other device, and makes sure that the other
device acknowledges the packets it receives.
Application layer
The application layer is the group of applications that require network communication. This is what the user
typically interacts with, such as email and messaging. Because the lower layers handle the details of
communication, the applications don’t need to concern themselves with this.

16. Client
A client is a computer or a program that, as part of its operation, relies on sending a request to another program or a
computer hardware or software that accesses a service made available by a server (which may or may not be located on
another computer). For example, web browsers are clients that connect to web servers and retrieve web pages for display.
Email clients retrieve email from mail servers. Online chat uses a variety of clients, which vary on the chat protocol being
used. Multiplayer video games or online video games may run as a client on each computer. The term "client" may also be
applied to computers or devices that run the client software or users that use the client software.
A client is part of a client–server model, which is still used today. Clients and servers may be computer programs run on
the same machine and connect via inter-process communication techniques. Combined with Internet sockets, programs
may connect to a service operating on a possibly remote system through the Internet protocol suite. Servers wait for
potential clients to initiate connections that they may accept.
The term was first applied to devices that were not capable of running their own stand-alone programs, but could interact
with remote computers via a network. These computer terminals were clients of the time-sharing mainframe computer.

17. server
In computing, a server is a piece of computer hardware or software (computer program) that provides functionality for
other programs or devices, called "clients". This architecture is called the client–server model. Servers can provide various
functionalities, often called "services", such as sharing data or resources among multiple clients, or performing
computation for a client. A single server can serve multiple clients, and a single client can use multiple servers. A client
process may run on the same device or may connect over a network to a server on a different device.Typical servers are
database servers, file servers, mail servers, print servers, web servers, game servers, and application servers.
Client–server systems are today most frequently implemented by (and often identified with) the request–response model:
a client sends a request to the server, which performs some action and sends a response back to the client, typically with a
result or acknowledgment. Designating a computer as "server-class hardware" implies that it is specialized for running
servers on it. This often implies that it is more powerful and reliable than standard personal computers, but alternatively,
large computing clusters may be composed of many relatively simple, replaceable server components.

18. ISP
An Internet service provider (ISP) is an organization that provides a myriad of services for accessing, using, or
participating in the Internet. Internet service providers can be organized in various forms, such as commercial,
community-owned, non-profit, or otherwise privately owned.
Internet services typically provided by ISPs can include Internet access, Internet transit, domain name registration, web
hosting, Usenet service, and colocation.
Example: WorldLink, Vianet

19. In 1990, Brookline, Massachusetts-based The World became the first commercial ISP.
ISP can be:
Access providers:
SPs employ a range of technologies to enable consumers to
connect to their network
Hosting ISPs:
Hosting ISPs routinely provide email, FTP, and web-hosting
services. Other services include virtual machines, clouds, or entire physical servers
where customers can run their own custom software
Transit ISPs:
Just as their customers pay them for Internet access, ISPs themselves
pay upstream ISPs for Internet access. An upstream ISP usually has a larger
network than the contracting ISP and/or is able to provide the contracting ISP with
access to parts of the Internet the contracting ISP by itself has no access to.

20. Virtual ISPs:
A Virtual ISP (VISP) is an operation which purchases services from
another ISP (sometimes called a "wholesale ISP") which allow the VISP's
customers to access the Internet using services and infrastructure owned and
operated by the wholesale ISP.
Free ISPs:
Free ISPs are Internet Service Providers (ISPs) which provide service
free of charge. Many free ISPs display advertisements while the user is connected;
like commercial television, in a sense they are selling the users' attention to the advertiser. Other free
ISPs, often called freenets, are run on a nonprofit basis, usually with volunteer staff

21. IP
An Internet Protocol address (IP address) is a numerical label assigned to each device connected to a computer network
that uses the Internet Protocol for communication. An IP address serves two main functions: host or network interface
identification and location addressing.
Internet Protocol version 4 (IPv4) defines an IP address as a 32-bit number.However, because of the growth of the Internet
and the depletion of available IPv4 addresses, a new version of IP (IPv6), using 128 bits for the IP address, was
standardized in 1998.IPv6 deployment has been ongoing since the mid-2000s.
IP addresses are written and displayed in human-readable notations, such as 172.16.254.1 in IPv4, and
2001:db8:0:1234:0:567:8:1 in IPv6. The size of the routing prefix of the address is designated in CIDR notation by
suffixing the address with the number of significant bits, e.g., 192.168.1.15/24, which is equivalent to the historically used
subnet mask 255.255.255.0.

22. The IP address space is managed globally by the Internet Assigned Numbers Authority (IANA), and by five regional
Internet registries (RIRs) responsible in their designated territories for assignment to local Internet registries, such as
Internet service providers (ISPs), and other end users. IPv4 addresses were distributed by IANA to the RIRs in blocks of
approximately 16.8 million addresses each, but have been exhausted at the IANA level since 2011. Only one of the RIRs
still has a supply for local assignments in Africa.[6] Some IPv4 addresses are reserved for private networks and are not
globally unique.

23. Domain Name System (DNS).
A domain name is an identification string that defines a realm of administrative autonomy,
authority, or control on the Internet. Domain names are formed by the rules and procedures of the
Domain Name System (DNS).
In general, a domain name represents an Internet Protocol (IP) resource, such as a
personal computer used to access the Internet, a server computer hosting a web site, or
the web site itself or any other service communicated via the Internet.

25. ● The right-most label conveys the top-level domain; for example, the domain name www.example.com belongs
to the top-level domain com.
● The hierarchy of domains descends from the right to the left label in the name; each label to the left specifies a
subdivision, or subdomain of the domain to the right. For example: the label example specifies a node
example.com as a subdomain of the com domain, and www is a label to create www.example.com, a subdomain
of example.com. Each label may contain from 1 to 63 octets. The empty label is reserved for the root node and
when fully qualified is expressed as the empty label terminated by a dot. The full domain name may not
exceed a total length of 253 ASCII characters in its textual representation.[8] Thus, when using a single
character per label, the limit is 127 levels: 127 characters plus 126 dots have a total length of 253. In practice,
some domain registries may have shorter limits.
● A hostname is a domain name that has at least one associated IP address. For example, the domain names
www.example.com and example.com are also hostnames, whereas the com domain is not. However, other top-
level domains, particularly country code top-level domains, may indeed have an IP address, and if so, they are
also hostnames.
● Hostnames impose restrictions on the characters allowed in the corresponding domain name. A valid hostname
is also a valid domain name, but a valid domain name may not necessarily be valid as a hostname.

26. Top-level domains
The top-level domains (TLDs) such as com, net and org are the highest level of domain names of the Internet. Top-level
domains form the DNS root zone of the hierarchical Domain Name System. Every domain name ends with a top-level domain
label.
Second-level and lower level domains
Below the top-level domains in the domain name hierarchy are the second-level domain (SLD) names. These are the names
directly to the left of .com, .net, and the other top-level domains. As an example, in the domain example.co.uk, co is the
second-level domain.
Internationalized domain names
The character set allowed in the Domain Name System is based on ASCII and does not allow the representation of names and
words of many languages in their native scripts or alphabets. ICANN approved the Internationalized domain name (IDNA)
system, which maps Unicode strings used in application user interfaces into the valid DNS character set by an encoding called
Punycode. For example, københavn.eu is mapped to xn--kbenhavn-54a.eu. Many registries have adopted IDNA.

27. Internet Connections
Dial-Up (Analog 56K).
Dial-up access is cheap but slow. A modem (internal or external) connects to the Internet after the computer
dials a phone number. This analog signal is converted to digital via the modem and sent over a land-line
serviced by a public telephone network. Telephone lines are variable in quality and the connection can be poor
at times. The lines regularly experience interference and this affects the speed, anywhere from 28K to 56K.
Since a computer or other device shares the same line as the telephone, they can’t be active at the same time.
DSL. DSL stands for Digital Subscriber Line. It is an internet connection that is always “on”. This uses 2 lines
so your phone is not tied up when your computer is connected. There is also no need to dial a phone number
to connect. DSL uses a router to transport data and the range of connection speed, depending on the service
offered, is between 128K to 8 Mbps.

28. Cable. Cable provides an internet connection through a cable modem and operates over cable TV lines.
There are different speeds depending on if you are uploading data transmissions or downloading. Since the
coax cable provides a much greater bandwidth over dial-up or DSL telephone lines, you can get faster access.
Cable speeds range from 512K to 20 Mbps.
Wireless. Wireless, or Wi-Fi, as the name suggests, does not use telephone lines or cables to connect to the
internet. Instead, it uses radio frequency. Wireless is also an always on connection and it can be accessed
from just about anywhere. Wireless networks are growing in coverage areas by the minute so when I mean
access from just about anywhere, I really mean it. Speeds will vary, and the range is between 5 Mbps to 20
Mbps.
Satellite. Satellite accesses the internet via a satellite in Earth’s orbit. The enormous distance that a signal
travels from earth to satellite and back again, provides a delayed connection compared to cable and DSL.
Satellite connection speeds are around 512K to 2.0 Mbps.
Cellular. Cellular technology provides wireless Internet access through cell phones. The speeds vary
depending on the provider, but the most common are 3G and 4G speeds. A 3G is a term that describes a 3rd
generation cellular network obtaining mobile speeds of around 2.0 Mbps. 4G is the fourth generation of cellular
wireless standards. The goal of 4G is to achieve peak mobile speeds of 100 Mbps but the reality is about 21
Mbps currently.

29. WWW
World Wide Web, which is also known as a Web, is a collection of websites or web pages stored in web servers
and connected to local computers through the internet. These websites contain text pages, digital images,
audios, videos, etc. Users can access the content of these sites from any part of the world over the internet
using their devices such as computers, laptops, cell phones, etc. The WWW, along with internet, enables the
retrieval and display of text and media to your device.
The building blocks of the Web are web pages which are formatted in HTML and connected by links called
"hypertext" or hyperlinks and accessed by HTTP. These links are electronic connections that link related pieces
of information so that users can access the desired information quickly. Hypertext offers the advantage to
select a word or phrase from text and thus to access other pages that provide additional information related to
that word or phrase.

30. A web page is given an online address called a Uniform Resource Locator (URL). A particular collection of web
pages that belong to a specific URL is called a website, e.g., www.facebook.com, www.google.com, etc. So,
the World Wide Web is like a huge electronic book whose pages are stored on multiple servers across the
world.
The World Wide Web was invented by a British scientist, Tim Berners-Lee in 1989. He was working at CERN at
that time. Originally, it was developed by him to fulfill the need of automated information sharing between
scientists across the world, so that they could easily share the data and results of their experiments and
studies with each other.

31. E mail
E-mail is defined as the transmission of messages on the Internet. It is one of the most commonly used
features over communications networks that may contain text, files, images, or other attachments. Generally,
it is information that is stored on a computer sent through a network to a specified individual or group of
individuals.
Email messages are conveyed through email servers; it uses multiple protocols within the TCP/IP suite. For
example, SMTP is a protocol, stands for simple mail transfer protocol and used to send messages whereas
other protocols IMAP or POP are used to retrieve messages from a mail server. If you want to login to your
mail account, you just need to enter a valid email address, password, and the mail servers used to send and
receive messages.

32. Advantages of Email
There are many advantages of email, which are as follows:
● Cost-effective: Email is a very cost-effective service to communicate with others as there are several
email services available to individuals and organizations for free of cost. Once a user is online, it does
not include any additional charge for the services.
● Email offers users the benefit of accessing email from anywhere at any time if they have an Internet
connection.
● Email offers you an incurable communication process, which enables you to send a response at a
convenient time. Also, it offers users a better option to communicate easily regardless of different
schedules users.
● Speed and simplicity: Email can be composed very easily with the correct information and contacts.
Also, minimum lag time, it can be exchanged quickly.
● Mass sending: You can send a message easily to large numbers of people through email.
● Email exchanges can be saved for future retrieval, which allows users to keep important conversations
or confirmations in their records and can be searched and retrieved when they needed quickly.

33. ● Email provides a simple user interface and enables users to categorize and filter their messages. This
can help you recognize unwanted emails like junk and spam mail. Also, users can find specific
messages easily when they are needed.
● As compared to traditional posts, emails are delivered extremely fast.
● Email is beneficial for the planet, as it is paperless. It reduces the cost of paper and helps to save the
environment by reducing paper usage.
● It also offers a benefit to attaching the original message at the time you reply to an email. This is
beneficial when you get hundreds of emails a day, and the recipient knows what you are talking about.
● Furthermore, emails are beneficial for advertising products. As email is a form of communication,
organizations or companies can interact with a lot of people and inform them in a short time.

34. Disadvantages of Email
● Impersonal: As compared to other forms of communication, emails are less personal. For example,
when you talk to anyone over the phone or meeting face to face is more appropriate for communicating
than email.
● Misunderstandings: As email includes only text, and there is no tone of voice or body language to
provide context. Therefore, misunderstandings can occur easily with email. If someone sends a joke on
email, it can be taken seriously. Also, well-meaning information can be quickly typed as rude or
aggressive that can impact wrong. Additionally, if someone types with short abbreviations and
descriptions to send content on the email, it can easily be misinterpreted.
● Malicious Use: As email can be sent by anyone if they have an only email address. Sometimes, an
unauthorized person can send you mail, which can be harmful in terms of stealing your personal
information. Thus, they can also use email to spread gossip or false information.
● Accidents Will Happen: With email, you can make fatal mistakes by clicking the wrong button in a
hurry. For instance, instead of sending it to a single person, you can accidentally send sensitive
information to a large group of people. Thus, the information can be disclosed, when you have clicked
the wrong name in an address list. Therefore, it can be harmful and generate big trouble in the
workplace.
● Spam: Although in recent days, the features of email have been improved, there are still big issues
with unsolicited advertising arriving and spam through email. It can easily become overwhelming and
takes time and energy to control.

35. ● Information Overload: As it is very easy to send email to many people at a time, which can create
information overload. In many modern workplaces, it is a major problem where it is required to move a
lot of information and impossible to tell if an email is important. And, email needs organization and
upkeep. The bad feeling is one of the other problems with email when you returned from vacation and
found hundreds of unopened emails in your inbox.
● Viruses: Although there are many ways to travel viruses in the devices, email is one of the common
ways to enter viruses and infect devices. Sometimes when you get a mail, it might be the virus come
with an attached document. And, the virus can infect the system when you click on the email and open
the attached link. Furthermore, an anonymous person or a trusted friend or contact can send infected
emails.
● Pressure to Respond: If you get emails and you do not answer them, the sender can get annoyed
and think you are ignoring them. Thus, this can be a reason to make pressure on your put to keep
opening emails and then respond in some way.
● Time Consuming: When you get an email and read, write, and respond to emails that can take up
vast amounts of time and energy. Many modern workers spend their most time with emails, which may
be caused to take more time to complete work.
● Overlong Messages: Generally, email is a source of communication with the intention of brief
messages. There are some people who write overlong messages that can take much time than
required.
● Insecure: There are many hackers available that want to gain your important information, so email is
a common source to seek sensitive data, such as political, financial, documents, or personal messages.
In recent times, there have various high-profile cases occurred that shown how email is insecure about
information theft.

36. FTP
● FTP stands for File transfer protocol.
● FTP is a standard internet protocol provided by TCP/IP used for transmitting the files from one host to
another.
● It is mainly used for transferring the web page files from their creator to the computer that acts as a
server for other computers on the internet.
● It is also used for downloading the files to computer from other servers.
● It provides the sharing of files.
● It is used to encourage the use of remote computers.
● It transfers the data more reliably and efficiently.

37. Advantages of FTP
● Speed: One of the biggest advantages of FTP is speed. The FTP is one of the fastest way to transfer
the files from one computer to another computer.
● Efficient: It is more efficient as we do not need to complete all the operations to get the entire file.
● Security: To access the FTP server, we need to login with the username and password. Therefore, we
can say that FTP is more secure.
● Back & forth movement: FTP allows us to transfer the files back and forth. Suppose you are a
manager of the company, you send some information to all the employees, and they all send
information back on the same server.

38. Disadvantages of FTP
● The standard requirement of the industry is that all the FTP transmissions should be encrypted.
However, not all the FTP providers are equal and not all the providers offer encryption. So, we will have
to look out for the FTP providers that provides encryption.
● FTP serves two operations, i.e., to send and receive large files on a network. However, the size limit of
the file is 2GB that can be sent. It also doesn't allow you to run simultaneous transfers to multiple
receivers.
● Passwords and file contents are sent in clear text that allows unwanted eavesdropping. So, it is quite
possible that attackers can carry out the brute force attack by trying to guess the FTP password.
● It is not compatible with every system.

39. TELNET
● The main task of the internet is to provide services to users. For example, users want to run different
application programs at the remote site and transfers a result to the local site. This requires a client-
server program such as FTP, SMTP. But this would not allow us to create a specific program for each
demand.
● The better solution is to provide a general client-server program that lets the user access any
application program on a remote computer. Therefore, a program that allows a user to log on to a
remote computer. A popular client-server program Telnet is used to meet such demands. Telnet is an
abbreviation for Terminal Network.
● Telnet provides a connection to the remote computer in such a way that a local terminal appears to be
at the remote side.

40. Uses of Internet
The Internet is a global networking system that can be used on most devices nowadays and has become an
essential part of our lives. In today's technological era, most of the companies are getting their operations
done over the Internet. There are various uses of the Internet by which companies and individuals are making
their daily tasks more productive and more comfortable.

42. Online Booking & Orders
The Internet has made it a lot easier for people to book tickets for buses, trains, flights
(domestic and international) directly using their devices from anywhere. People can also book a
taxi by choosing their current location, and they will be picked up or dropped at a specified
location. Now no one needs to wait in long queues for their turn to book tickets at the ticket
counter.
Besides, people can order a wide variety of products at home using the Internet and devices. It
can range from grocery products to ready to eat, fashionable clothes to medicines. Most items
can be ordered at home and received directly at the door.
Cashless Transactions
Most countries are promoting cashless transactions and digital payments. This helps people not
carry much cash. People can pay their bills through debit or credit cards using POS devices.
These devices are connected to the payment gateway on the Internet. Besides, People can also
use their smartphone and the Internet for processing transactions on UPI (Unified Payment
Interface). It does not even require them to carry their cards. The UPI payment method is
continuously evolving and is expected to cover most transactions in the near future.

43. Education
Most of the devices nowadays are connected through the Internet. The Internet has the
availability of broad educational content on any topic with different types. People can study the
relevant topic just by spending a couple of minutes over the Internet. Internet Search engines
help people quickly find the relevant study material in multiple formats (such as images, videos,
documents, etc.). This helps eliminate the need to go to the library to read several books to find
the desired information.
Besides, the Internet has also enabled students to participate in their classes through video
conferencing, where students can connect with their teachers or professionals anywhere in the
world.
Electronic Mail
Email or electronic mail is one of the first significant uses of the Internet. The email has enabled
faster communication between people on the Internet. Using email, people can quickly share
information, data files, such as images, audio, video, and other types of files. The use of email
has significantly reduced paper use, which was the primary source of communication in the olden
days. Anyone can have a free email address and can easily communicate with others. This has
also reduced the load on the physical mail system, although it is still in use.

44. Online Banking & Trading
The way of banking has changed after the introduction of the Internet. The Internet has made
banking online where people can manage their bank accounts while sitting at home or traveling
abroad. Nowadays, most of the features of banking are right in people's hands. With the help of
online banking, people can securely transfer the money from one account to another, change
their ATM pins, apply for the physical or virtual credit cards, update credit card limits, enable or
disable international transactions, track their transactions, and many more. Also, they can even
raise an online complaint or contact to bank's support staff.
Apart from this, the Internet has made it a lot easier for people to trade in the Stock market
from anywhere. People can easily buy, sell, or manage stocks online.
Social Networking
Social networking sites have connected people around the world. Social networking is an
essential part of the Internet. With the help of the Internet, people have got the ability to form
social groups where they can share information, thoughts and ideas about anything. The social
networking platform is the largest source of content, covering everything from informative
content to entertainment. The best thing is that people don't have to pay anything to use these
services. This helps businesses develop their community and promote their products.

45. Entertainment
The Internet is the most effective means of entertainment. There are various options available
on the Internet, which people can try, such as watching movies, playing online games, listening
to songs, etc. The Internet has also made it easy for people to download entertainment items to
their local storage. Using the Internet, people can also share their videos, songs, pictures online
with others. Also, nowadays, people can watch live TV or sports on the Internet.
E-Commerce
The Internet is not just limited to ordering things; it can also be used to sell products. Many e-
commerce websites allow businesses and individuals to sell their products. Products are
purchased by these e-commerce companies, stored in their warehouses, packaged in their brand
packaging, and distributed by themselves. E-commerce companies charge some commission to
distribute goods to customers. Also, they offer great discounts and offers to customers. The best
thing is that customers do not have to go to physical stores.
Besides, sellers can also create their website and list their products there. They can refer to all
information about the product, answer customer questions and provide online payment options
to their customers. All these things are possible on the Internet.

46. File Transfer
The Internet has made file transfer between systems or devices easier. With FTP (File Transfer
Protocol), data can be securely exchanged over the Internet. FTP is mainly beneficial when large
files need to be transferred because email allows sharing files with limited size. FTP is the best
way to exchange information between two stakeholders. This method is still quite popular and in
use.