The document provides an overview of cloud computing, highlighting its definition, advantages, and applications across various sectors, particularly during the COVID-19 pandemic. It describes different types of cloud services such as public, private, hybrid, and community clouds, along with their respective use cases. Additionally, the document details various cloud service models including Software-as-a-Service (SaaS), Platform-as-a-Service (PaaS), and Infrastructure-as-a-Service (IaaS).

1. Cloud Computing

2. CONCEPTS
Introduction to Cloud Computing.
Advantages and Disadvantages of Cloud Computing

3. Introduction
One of the most important and highly useful invention in the technical advancement
is cloud computing. It facilitates its services in almost all sectors based on computer
applications. For instance, in a pandemic situation caused by COVID-19, most of
the companies, organizations, business firms of both private and government sectors
throughout the globe are using the cloud computing applications for smooth running
of their activities. In particular, the online teaching tools are playing major role in
the educational system. The application of cloud computing is not limited to a
particular sector, it covers almost all sectors. So, in this context, an overview of
cloud computing and its applications are discussed in present article.

4. cloud computing is the delivery of computing services—including
servers, storage, databases, networking, software, analytics, and
intelligence—over the internet (“the cloud”) to offer faster innovation,
flexible resources, and economies of scale.
Cloud computing is the way to access computing technique through internet.
It consists of both software and hardware services, so that the user can locate
easily anywhere in the world.Recently, academics as well as business
industries paid a great deal of attention to cloud computing. The main
objective of cloud computing is to reduce the cost of application tools and
provide 24X7 hours online services to the user.
What is Cloud computing?

5. What is Cloud computing?
The term cloud refers to a network or the internet. It is a technology that uses
remote servers on the internet to store, manage, and access data online rather than
local drives. The data can be anything such as files, images, documents, audio, video,
and more.
There are the following operations that we can do using cloud computing:
 Developing new applications and services
 Storage, back up, and recovery of data
 Hosting blogs and websites
 Delivery of software on demand
 Analysis of data
 Streaming videos and audios

6. Why Cloud Computing?
Small as well as large IT companies, follow the traditional methods to provide the
IT infrastructure. That means for any IT company, we need a Server Room that is
the basic need of IT companies.
In that server room, there should be a database server, mail server, networking,
firewalls, routers, modem, switches, QPS (Query Per Second means how much
queries or load will be handled by the server), configurable system, high net speed,
and the maintenance engineers.
To establish such IT infrastructure, we need to spend lots of money. To overcome all
these problems and to reduce the IT infrastructure cost, Cloud Computing comes
into existence.

7. Characteristics of Cloud Computing:
The characteristics of cloud computing are given below:
a) Agility
The cloud works in a distributed computing environment. It shares resources
among users and works very fast.
b) High availability and reliability
The availability of servers is high and more reliable because the chances of
infrastructure failure are minimum.
c) High Scalability
Cloud offers "on-demand" provisioning of resources on a large scale, without
having engineers for peak loads.

8. d) Multi-Sharing
With the help of cloud computing, multiple users and applications can work
more efficiently with cost reductions by sharing common infrastructure.
e) Device and Location Independence
Cloud computing enables the users to access systems using a web browser
regardless of their location or what device they use e.g. PC, mobile phone, etc. As
infrastructure is off-site (typically provided by a third-party) and accessed via the Internet,
users can connect from anywhere.

9. f) Maintenance
Maintenance of cloud computing applications is easier, since they do not need to
be installed on each user's computer and can be accessed from different places. So, it reduces
the cost also.
g) Low Cost
By using cloud computing, the cost will be reduced because to take the services of
cloud computing, IT company need not to set its own infrastructure and pay-as-per usage of
resources.
h) Services in the pay-per-use mode
Application Programming Interfaces (APIs) are provided to the users so that they can access
services on the cloud by using these APIs and pay the charges as per the usage of services.

10. TYPES OF CLOUDS
1. Public Clouds :Public clouds are owned and operated by companies that use them to offer rapid
access to affordable computing resources to other organizations or individuals. With public cloud
services, users don’t need to purchase hardware, software or supporting infrastructure, which is
owned and managed by providers. Public clouds are made available to the general public by a service
provider who hosts the cloud infrastructure. Examples of public clouds include Amazon Elastic
Compute Cloud (EC2), IBM’s Blue Cloud, Sun Cloud, Google AppEngine and Windows Azure Services
Platform. A public cloud is the obvious choice when:
 Your standardized workload for applications is used by lots of people, such as e-mail.
 You need to test and develop application code.
 You need incremental capacity. You’re doing collaboration projects.

2. Private clouds : are data center architectures owned by a particular organization that provides
flexibility, scalability, provisioning, automation and monitoring. The goal of a private cloud is not sell
“as-a-service” offerings to external customers but instead to gain the benefits of cloud architecture
without giving up the control of maintaining your own data center. Private clouds are more expensive
but also more secure when compared to public clouds. Private cloud is needed in the following cases:
• You need data sovereignty but want cloud efficiencies
• You want consistency across services
• Your data center must become more efficient
• You want to provide private cloud services

11. 3. Hybrid Clouds : Hybrid Clouds are a composition of two or more clouds (private, community
or public) that remain unique entities but are bound together offering the advantages of
multiple deployment models. In a hybrid cloud, you can control third party cloud providers in
either a full or partial manner; increasing the flexibility of computing. For instance during peak
periods individual applications, or portions of applications can be migrated to the Public Cloud.
Here are situations where a hybrid environment is suitable:
•Your company wants to use a SaaS application but is concerned about security.
•Your company offers services that are tailored for different vertical markets.
•You can provide public cloud to your customers while using a private cloud for internal IT.
4. Community Clouds : A Community Cloud is designed to meet the needs of a community.
Such communities involve people or organization that has shared interests. This includes
industrial groups, research groups, standards groups, and so on. Community clouds are a
hybrid form of private clouds built and operated specifically for a targeted group. These
communities have similar cloud requirements and their ultimate goal is to work together to
achieve their business objectives. The goal of these clouds is to have participating
organizations realize the benefits of a public cloud with the added level of privacy, security, and
policy compliance usually associated with a private cloud. Situations where a community cloud
is best:
• Government organizations within a state that need to share resources
•A private HIPAA compliant cloud for a group of hospitals or clinics
• Telco community cloud for Telco DR to meet specific FCC regulations

12. SERVICES OF CLOUD COMPUTING
1. Software-as-a-Service (SaaS) : A software that is deployed over the Internet is
considered as Software as a Service (SaaS).
2. Platform-as-a-Service (PaaS) : A computing platform that allow the designing
of web applications quickly and easily without the complexity of buying and
maintaining the software and infrastructure is defined as Platform as a Service.
3. Infrastructure-as-a-Service (IaaS) : Infrastructure as a Service (IaaS) is a way
of distributing Cloud computing infrastructure – servers, storage, network and
operating systems – as an on-demand service. Instead of buying servers,
software, Data center space or network equipment, clients instead buy those
resources as a fully outsourced service on demand.

13. Thank You