CLOUD COMPUTING

UNIT 1
What Is Cloud Computing?

Cloud computing is the delivery of different services through the Internet. These
resources include tools and applications like data storage, servers, databases,
networking, and software.

Rather than keeping files on a proprietary hard drive or local storage device,
cloud-based storage makes it possible to save them to a remote database. As long
as an electronic device has access to the web, it has access to the data and the
software programs to run it.

Cloud computing is a popular option for people and businesses for a number of
reasons including cost savings, increased productivity, speed and efficiency,
performance, and security.

Examples of Cloud Computing

Cloud computing is the use of hardware or software off-site that is accessed over
networks for computing needs. Examples of cloud computing depend on the type
of cloud computing services being provided.

The main types of cloud computing include software as a service, platform as a

service, and infrastructure as a service. Serverless computing, also known as
function as a service (FaaS), is also a popular method of cloud computing for
businesses.

Underlying Principles of Parallel and Distributed Computing System

The terms parallel computing and distributed computing are used
interchangeably.

 It implies a tightly coupled system.

 It is characterised by homogeneity of components (Uniform Structure).
 Multiple Processors share the same physical memory.

Parallel Processing
 Processing multiple tasks simultaneously in multiple processors is called
parallel processing.
  Parallel program consists of multiple processes (tasks) simultaneously
solving a given problem.
 Divide-and-Conquer technique is used.

History of Cloud Computing

Before emerging the cloud computing, there was Client/Server computing which
is basically a centralized storage in which all the software applications, all the data
and all the controls are resided on the server side.

If a single user wants to access specific data or run a program, he/she need to
connect to the server and then gain appropriate access, and then he/she can do
his/her business.

Then after, distributed computing came into picture, where all the computers are
networked together and share their resources when needed.

On the basis of above computing, there was emerged of cloud computing

concepts that later implemented.

At around in 1961, John MacCharty suggested in a speech at MIT that computing

can be sold like a utility, just like a water or electricity. It was a brilliant idea, but
like all brilliant ideas, it was ahead if its time, as for the next few decades, despite
interest in the model, the technology simply was not ready for it.

But of course time has passed and the technology caught that idea and after few
years we mentioned that:

In 1999, Salesforce.com started delivering of applications to users using a simple

website. The applications were delivered to enterprises over the Internet, and this
way the dream of computing sold as utility were true.

In 2002, Amazon started Amazon Web Services, providing services like storage,
computation and even human intelligence. However, only starting with the launch
of the Elastic Compute Cloud in 2006 a truly commercial service open to
everybody existed.

In 2009, Google Apps also started to provide cloud computing enterprise

applications.

Cloud Computing Architecture

As we know, cloud computing technology is used by both small and large
organizations to store the information in cloud and access it from anywhere at
anytime using the internet connection.
Cloud computing architecture is a combination of service-oriented architecture
and event-driven architecture.

Cloud computing architecture is divided into the following two parts –

 Front End
 Back End

The below diagram shows the architecture of cloud computing –

Front End
The front end is used by the client. It contains client-side interfaces and
applications that are required to access the cloud computing platforms. The front
end includes web servers (including Chrome, Firefox, internet explorer, etc.), thin
& fat clients, tablets, and mobile devices.

Back End

The back end is used by the service provider. It manages all the resources that are
required to provide cloud computing services. It includes a huge amount of data
storage, security mechanism, virtual machines, deploying models, servers, traffic
control mechanisms, etc.

Types of Cloud Computing

Major Players in Cloud Computing
Amazon Web Services (AWS) pioneered the IaaS market when the service
went public in 2006. The AWS offering is an integrated IaaS and platform as a
service (PaaS) solution, with Elastic Compute Cloud (EC2) delivering multitenant
and single-tenant VMs and bare-metal servers. AWS continues to lead the pack,
performing strongly in many of Gartner’s critical use cases for CIPS and having a
large resource base to pull from. As Gartner notes, AWS provides more than half
of Amazon’s operating income.

Microsoft Azure offers an integrated IaaS and PaaS solution. The vendor
provides metered-by-the-second Hyper-V-virtualized multitenant compute (Azure
Virtual Machines), as well as specialized large instances (such as for SAP HANA).
Gartner noted its commitment to better serving software developers; in
particular, Microsoft has made efforts to support the open-source software
community. It also has a high market share in the application developer PaaS
segment thanks to its suite of DevOps and application development tools.

Google Cloud delivers IaaS, application platform as a service (aPaaS), and PaaS
services. Some of the vendor’s capabilities include object storage, a Docker
container service (Google Kubernetes Engine), and event-driven serverless
computing (Google Cloud Functions). Google has put a strong emphasis on hybrid
capabilities, particularly with the launch of Anthos last year, and its continued
focus on supporting open-source software. Gartner’s clients particularly praised
Google’s data science and significant data capabilities.
Issue of Cloud Computing

1, Privacy:
The user data can be accessed by the host company with or without permission.
The service provider may access the data that is on the cloud at any point in time.
They could accidentally or deliberately alter or even delete information.

2. Compliance:
There are many regulations in places related data and hosting. To comply with
regulations (Federal Information Security Management Act, Health Insurance
Portability and Accountability Act, etc.) the user may have to adopt deployment
modes that are expensive.

3. Security:
Cloud-based services involve third-party for storage and security. Can one assume
that a c3loud-based company will protect and secure one’s data if one is using
their services at a very low or for free? They may share user’s information with
others. Security presents a real threat to the cloud.

4. Sustainability:

This issue refers to minimizing the effect of cloud computing on the environment.
Citing the server’s effects on the environmental effects of cloud computing, in
areas where climate favours natural cooling and renewable electricity is readily
available, the countries with favourable conditions, such as Finland, Sweden, and
Switzerland are trying to attract cloud computing data centres. But other than
nature’s favours, would these countries have enough technical infrastructure to
sustain the high-end clouds?

5. Abuse:

While providing cloud services, it should be ascertained that the client is not
purchasing the services of cloud computing for a nefarious purpose. In 2009, a
banking Trojan illegally used the popular Amazon service as a command and
control channel that issued software updates and malicious instruction to PCs
that were infected by the malware So the hosting companies and the servers
should have proper measures to address these issues.

6, Higher Cost: If you want to use cloud services uninterruptedly then you need
to have a powerful network with higher bandwidth then ordinary internet
networks and also if your organization is broad and large so ordinary cloud service
subscription won’t suit your organization. Otherwise, you might face hassle in
utilizing an ordinary cloud service while working on complex projects and
applications. This is a major problem before small organisations, that restricts
them from diving into cloud technology for their business.

7. Recovery of lost data in contingency: Before subscribing any cloud service

provider goes through all norms and documentations and check whether their
services match your requirements and sufficient well-maintained resource
infrastructure with proper upkeeping. Once you subscribed the service you almost
handover your data into the hands of the third party. If you are able to choose
proper cloud service then in future you don’t need to worry about the recovery of
lost data in any contingency.

8. Upkeeping(management) of Cloud: Maintaining a cloud is a herculin task

because a cloud architecture contains a large resources infrastructure and other
challenges and risks as well, user satisfaction etc. As users usually pay for how
much they have consumed the resources. So, some times it becomes hard to
decide how much should be charged in case if the user wants scalability and
extend the services.

9. Lack of resources/skilled expertise: One of the major issue that

companies and enterprises are going through today is the lack of resources and
skilled employees. Every second organization is seeming interested or has already
been moved to cloud services. That’s why the workload in the cloud is increasing
so the cloud service hosting companies need continuous rapidly advancement.
Due to these factors, organizations are having a tough time keeping up to date
with the tools. As new tools and technologies are emerging every day so more
skilled/trained employ

Eucalyptus
Eucalyptus is an open source software platform for implementing Infrastructure
as a Service (IaaS) in a private or hybrid cloud computing environment.

The Eucalyptus cloud platform pools together existing virtualized infrastructure to

create cloud resources for infrastructure as a service, network as a service and
storage as a service. The name Eucalyptus is an acronym for Elastic Utility
Computing Architecture for Linking Your Programs To Useful Systems.

Eucalyptus was founded out of a research project in the Computer Science

Department at the University of California, Santa Barbara, and became a for-profit
business called Eucalyptus Systems in 2009. Eucalyptus Systems announced
formal agreement with Amazon Web Services (AWS) in March 2012, allowing
administrators to move instances between a Eucalyptus private cloud and the
Amazon Elastic Compute Cloud (EC2) to create a hybrid cloud. The partnership
also allows Eucalyptus to work with Amazon’s product teams to develop unique
AWS-compatible features.

Eucalyptus features include:

 Supports both Linux and Windows virtual machines (VMs).

 Application program interface- (API) compatible with Amazon EC2 platform.
 Compatible with Amazon Web Services (AWS) and Simple Storage Service
(S3).
 Works with multiple hypervisors including VMware, Xen and KVM.
 Can be installed and deployed from source code or DEB and RPM packages.
 Internal processes communications are secured through SOAP and WS-
Security.
 Multiple clusters can be virtualized as a single cloud.

Nimbus
Nimbus is an open-source toolkit to convert a computer cluster into an
Infrastructure-as-a-Service cloud to provide compute cycles for scientific
communities. It allows a client to lease remote resources by deploying virtual
machines (VMs) on those resources and configuring them to represent an
environment desired by the user.

Nimbus is comprised of two products:

 Nimbus Infrastructure is an open source EC2/S3-compatible Infrastructure-

as-a-Service implementation specifically targeting features of interest to
the scientific community such as support for proxy credentials, batch
schedulers, best-effort allocations and others.
 Nimbus Platform is an integrated set of tools, operating in a multi-cloud
environment, that deliver the power and versatility of infrastructure clouds
to scientific users. Nimbus Platform allows you to reliably deploy, scale, and
manage cloud resources.

The Nimbus cloud client allows the user to provision customized compute nodes,
called a workspace, and maintain full control over it using a leasing model based
on the Amazon’s Elastic Compute Cloud (EC2) service.

OpenNebula
OpenNebula is a free and open source software solution for building clouds and
for data centre virtualisation. It is based on open technologies and is distributed
under the Apache License 2. OpenNebula has features for scalability, integration,
security and accounting. It offers cloud users and administrators a choice of
interfaces.

OpenNebula is an open source platform for constructing virtualised private, public

and hybrid clouds. It is a simple yet feature-rich, flexible solution to build and
manage data centre virtualisation and enterprise clouds. So, with OpenNebula,
virtual systems can be administered and monitored centrally on different Hyper-V
and storage systems. When a component fails, OpenNebula takes care of the
virtual instances on a different host system. The integration and automation of an
existing heterogeneous landscape is highly flexible without further hardware
investments.

Cloud Computing is one of the hottest topics in town. It has completely

transformed how modern-day applications are developed and maintained with
high scalability and low latency.

CloudSim
CloudSim is an open-source framework, which is used to simulate cloud
computing infrastructure and services. It is developed by the CLOUDS Lab
organization and is written entirely in Java. It is used for modelling and simulating
a cloud computing environment as a means for evaluating a hypothesis prior to
software development in order to reproduce tests and results.

For example, if you were to deploy an application or a website on the cloud and
wanted to test the services and load that your product can handle and also tune
its performance to overcome bottlenecks before risking deployment, then such
evaluations could be performed by simply coding a simulation of that
environment with the help of various flexible and scalable classes provided by the
CloudSim package, free of cost.