Rajalakshmi Engineering College

CLOUD COMPUTING
UNIT I
CLOUD COMPUTING CS19741

Department
of CSE
 UNIT III
INTRODUCTION
Design of HDFS

Concepts and Java Interface

Dataflow of File read & File write

Map Reduce, Input splitting,

map and reduce functions.

Case Study: Design and Implementation of Hive, Pig, HBase.

Department
of CSE
 What is the cloud?
"The cloud" refers to servers that are accessed over the Internet, and the
software and databases that run on those servers. Cloud servers are in data
centers all over the world. By using cloud computing, users and companies do
not have to manage physical servers themselves or run software applications on
their own machines.

The cloud enables users to access the same files and applications from almost
any device, because the computing and storage takes place on servers in a data
center, instead of locally on the user device.
 What is Cloud Computing?
The term “Cloud Computing” refers to services provided by the cloud that is responsible for
delivering of computing services such as servers, storage, databases, networking, software,
analytics, intelligence, and more, over the Cloud (Internet). Cloud computing applies a
virtualized platform with elastic resources on demand by provisioning hardware, software,
and data sets dynamically.
 BASIC CONCEPTS & TERMINOLOGIES
VIRTUALIZATION
Virtualization is a technique, which allows to share a single physical instance of a resource
or an application among multiple customers and organizations. It does by assigning a logical
name to a physical storage and providing a pointer to that physical resource when
demanded.
GRID COMPUTING
Grid computing is defined as a distributed architecture of multiple
computers connected by networks that work together to accomplish a
joint task. This system operates on a data grid where computers interact
to coordinate jobs at hand. This article explains the fundamentals of grid
computing in detail.
 CLUSTERING
At a high level, a computer cluster is a group of two or more computers,
or nodes, that run in parallel to achieve a common goal. This allows
workloads consisting of a high number of individual, parallelizable tasks
to be distributed among the nodes in the cluster. As a result, these tasks
can leverage the combined memory and processing power of each
computer to increase overall performance.
 CLOUD CHARACTERSTICS
According to NIST (National institute of standards) there are five essential characteristics of
cloud computing:
On Demand Self Service
Broad network access
Resource Pooling
Rapid elasticity
Measured service
Multi-Tenancy
Virtualization
Resiliency and Availability
Security
Pay-Per-Use Pricing
On Demand Self Services: User gets on demand computer services
like email, applications etc. without interacting with the service provider.
Some of the cloud service providers are- Amazon Web Service,
Microsoft, IBM, Salesforce.com

Broad Network Access: Broad network access means that cloud

services are accessible from anywhere in the world via the internet.
This means that you don’t have to worry about working remotely—
you can simply log into your account from wherever there’s an
internet connection! These fundamental characteristics of Cloud
Computing also enable them to upload data to the cloud from
anywhere.
Rapid Elasticity Rapid elasticity refers to the ability of a cloud service
provider (CSP) like Amazon Web Services (AWS) or Microsoft Azure
to add more capacity. The ability to quickly scale up and down capacity
is perhaps the most important characteristic of cloud computing.
Because the cloud provider owns the hardware, they can adjust
resources as needed to accommodate peak loads.

Resource Pooling Resource pooling is one of the essential

characteristics of Cloud Computing. By pooling resources across
multiple users and applications, cloud computing can be more cost-
effective than traditional IT systems. This resource pooling also
makes it easier to scale up or down resources, which helps
businesses respond quickly to changes in demand without having to
invest in new hardware or software.
Measured Service This is a characteristic of cloud computing that
refers to the ability to pay for only what you use. You are billed for the
resources you have used, rather than paying for your entire
infrastructure based on capacity.

Multi-Tenancy One of the best characteristics of Cloud

Computing is Multi Tenancy. Multi-tenancy refers to the fact that
multiple customers share the same physical infrastructure. This
means that different companies’ data is stored separately, but they
all have access to the same services.

Virtualization The ability to run multiple operating systems on a

single server. This can be done by using virtual machines, which are
software that allows you to run an entire operating system on a
single machine.
Resiliency and Availability: The ability for your data to be
resilient in the event of a failure or to be available when it’s needed.
This can be accomplished through redundancy and failover features.

Security: Data security is one of the best characteristics of Cloud

Computing. Cloud computing features provide security by using
multiple layers of protection, including firewalls, encryption, and
identity management systems. It provides enhanced security for your
business data and applications by leveraging standard practises in
information security.

Pay-Per-Use Pricing :You can use resources as you need them

instead of paying for storage space that may go unused. This is one of
the many effective cloud computing features.
Cloud Reference Model
Roles & Boundaries
Cloud Provider: The organization that provides cloud-based IT resources
is the cloud provider.

Cloud Consumer: A cloud consumer is an organization (or a human) that

has a formal contract or arrangement with a cloud provider to use IT
resources made available by the cloud provider.

Cloud Service Owner: The person or organization that legally owns a cloud
service is called a
cloud service owner.

Cloud Resource Administrator: A cloud resource administrator is the

person or organization responsible for administering a cloud-based IT resource
(including cloud services).
Organizational Boundary: An organizational boundary represents
the physical perimeter that surrounds a set of IT resources that
are owned and governed by an organization.

Trust Boundary: When an organization assumes the role of cloud

consumer to access cloud-based IT resources, it needs to extend its
trust beyond the physical boundary of the organization to include
parts of the cloud environment.
 ADDITIONAL ROLES
• The NIST Cloud Computing Reference Architecture defines the following supplementary
roles:

• Cloud Auditor – A third-party (often accredited) that conducts independent

assessments of cloud environments assumes the role of the cloud auditor. The typical
responsibilities associated with this role include the evaluation of security controls,
privacy impacts, and performance. The main purpose of the cloud auditor role is to
provide an unbiased assessment (and possible endorsement) of a cloud environment to
help strengthen the trust relationship between cloud consumers and cloud providers.

• Cloud Broker – This role is assumed by a party that assumes the responsibility of
managing and negotiating the usage of cloud services between cloud consumers and cloud
providers. Mediation services provided by cloud brokers include service intermediation,
aggregation, and arbitrage.

• Cloud Carrier – The party responsible for providing the wire-level connectivity
between cloud consumers and cloud providers assumes the role of the cloud carrier.
This role is often assumed by network and telecommunication providers.
Cloud Architecture
 Cloud Delivery Model
A cloud delivery model represents a specific, pre-packaged combination of
computing resources offered by a cloud provider. Each model is
classified as a different type of cloud service offering. The three main
cloud delivery models are:

•IaaS - Infrastructure as a Service

•PaaS - Platform as a Service

•SaaS - Software as a Service

Infrastructure as a Service - IaaS
• The IaaS delivery model represents a self-contained environment that comprises
the infrastructure-centric IT resources to access and manage via cloud service-
based interfaces and tools.
• It may include hardware, networks, connectivity, operating systems, and other
resources. Unlike traditional hosting or outsourcing environments, with IaaS,
resources are virtualized and packaged into bundles that help simplify the
infrastructure's up-front runtime scaling and customization.
• The general purpose of an IaaS environment is to provide cloud consumers with
a high level of control and responsibility for its configuration, utilisation and
management.
• The IT resources provided by IaaS are usually not pre-configured, thus placing
the administrative responsibility upon the cloud consumer.
• Therefore, this model is used by cloud consumers who require a high level of
control over the cloud-based environment they intend to create.
 Platform as a Service - PaaS
• The PaaS delivery model is a pre-defined “ready-to-use” environment that
typically contains deployed and configured IT resources.

• PaaS relies on using a ready-made environment that holds a set of pre-packaged

products and tools to support the entire lifecycle of custom applications. A PaaS
requires an IaaS. It brings development and deployment together to create an
easier way to build, deploy, and scale applications.

• By using PaaS, the cloud consumer is spared the administrative burden of setting
up and maintaining the infrastructure of the resources provided in the IaaS
model. It ensures that developers have a well-tested and integrated environment
to create applications.

• However, the cloud consumer has less control over the underlying IT resources
that host and configure the platform.
Software as a Service - SaaS
• A software program is provided as a cloud service and made available as
a service or utility. Applications are created and hosted by a provider in
a multitenant model.

• In other words, the SaaS model allows a reusable cloud service to be

openly available to a range of cloud consumers. Customers pay for its
consumption on a monthly or yearly basis. An entire marketplace
contains SaaS products that can be leased and used for different
purposes.
• A cloud consumer is granted limited administrative control over a SaaS
product. It is entirely provisioned by the cloud provider, but it can be
legally owned by the entity that owns the cloud service.
Cloud Deployment Model
• Cloud Deployment Model acts as a virtual computing environment that
offers a choice of deployment model according to how much data users
want to store and who will have access to the infrastructure. It signifies
how servers are deployed and provisioned over the internet so that
various organizations and companies can access these servers without
configuring them.
• Using cloud deployment models benefits various companies in
many ways, such as boosting productivity and providing a
competitive advantage. There are mainly four Cloud Deployment
Models available.

Public Cloud Private Cloud

Community Cloud Hybrid Cloud
 Public Cloud
• Public cloud is a commonly adopted cloud model, where the cloud
services provider owns the infrastructure and openly provides
access to it for the public to consume.
• As the service provider owns the hardware and supporting networking
infrastructure, it is under the service provider’s full control. The service
provider is responsible for the physical security, maintenance, and
management of the data center where the infrastructure resides. The
underlying infrastructure is, therefore, outside of the customer’s control
and also away from the customer’s physical location.
• Infrastructure is managed primarily using a web browser but can also be
manipulated using an API, on the command line, or using infrastructure-
as-code tools such as Terraform.
• Commonly used public clouds include Microsoft Azure, Amazon AWS,
Google Cloud, Oracle Cloud, and Alibaba Cloud.
Private Cloud
• Private Cloud lets you use the infrastructure and resources for a single
organization. Users and organizations do not share resources with other
users. That is why it is also called as Internal or corporate model.
Private clouds are more costly than public clouds due to their costly
maintenance.
• Private cloud provides high security and data privacy since only authorized
users can access the resources.
• It offers high scalability and flexible deployment options that allow
companies to customize their infrastructures as per the need.
• Private Cloud supports a legacy system that cannot access the public cloud.
 Community Cloud
• The community Deployment Model is somewhat similar to the Private
cloud. In the private cloud, only one user or organization owns the cloud
server.
• In Community Cloud, several companies with the same backgrounds
share the cloud server. If all organizations or companies have the same
set of security protocols and performance requirements, and goals, this
multi-tenant architecture can help them save cost and boost efficiency. This
model can be used in the case of project development, implementation, and
maintenance.
• It is a very cost-effective solution as the cost is splitting into multiple
partners.
• It improves security, data privacy, and reliability, making it the perfect choice
for the government, banks, and universities.
• As this model is specially designed for a group of organizations, it lets you
easily collaborate and share the data.
Hybrid Cloud
• The Hybrid Cloud is a combination of both public and private
clouds. Very few companies and organizations can migrate their tech
stack to cloud computing rapidly in one go.

• Hence, Cloud vendors came up with a hybrid cloud that offers a smooth
transition with public and private cloud facilities. They keep the sensitive
data in the private cloud and non-sensitive data in the public cloud.

• Typically businesses may have some presence on-premise, and utilizing

this hardware until it has reached end-of-life in the private cloud will
likely be an attractive option if the business already owns the hardware.
In the hybrid model, this can be used to form part of the private cloud.
• ne of the major advantages of a hybrid cloud is that it comes up at a
reasonable cost.
• It enhances the scalability and flexibility of resources.