Cloud Computing_Module1_ updated.pptx

Module1:
Introduction, Cloud Infrastructure: Cloud computing, Cloud
computing delivery models and services, Ethical issues, Cloud
vulnerabilities.

What is Cloud Computing?
• Cloud Computing is defined as storing and accessing of data and
computing services over the internet.
• It doesn’t store any data on your personal computer. It is the on-
demand availability of computer services like servers, data storage,
networking, databases, etc.
• The main purpose of cloud computing is to give access to data centers
to many users.
• Users can also access data from a remote server.

Cloud Computing refers
to manipulating,
configuring, and accessing the
hardware and software resources
remotely. It offers online data
storage, infrastructure, and
application.
Cloud computing offers platform
independency, as the software is
not required to be installed locally
on the PC. Hence, the Cloud
Computing is making our business

Why Cloud Computing?
• With increase in computer and Mobile user’s, data storage has become a priority in all fields.
• Large and small scale businesses today thrive on their data & they spent a huge amount of
money to maintain this data. It requires a strong IT support and a storage hub.
• For them Cloud Computing is a cheaper solution. Perhaps its efficiency in storing data,
computation and less maintenance cost has succeeded to attract even bigger businesses as
well.
• While accessing e-mail service our data is stored on cloud server and not on our computer.
The technology and infrastructure behind the cloud is invisible

Hosting a cloud: There are three layers in cloud computing. Companies use these layers based
on the service they provide.
Infrastructure
Platform
Application

Benefits of Cloud Hosting:
Scalability: With Cloud hosting, it is easy to grow and shrink the number and size of servers based on the need. This is
done by either increasing or decreasing the resources in the cloud. This ability to alter plans due to fluctuation in business
size and needs is a superb benefit of cloud computing, especially when experiencing a sudden growth in demand.
Instant: Whatever you want is instantly available in the cloud.
Save Money: An advantage of cloud computing is the reduction in hardware costs. Instead of purchasing in-house
equipment, hardware needs are left to the vendor. For companies that are growing rapidly, new hardware can be large,
expensive, and inconvenient. Cloud computing alleviates these issues because resources can be acquired quickly and
easily. Even better, the cost of repairing or replacing equipment is passed to the vendors.
Reliability: Rather than being hosted on one single instance of a physical server, hosting is delivered on a virtual partition
that draws its resource, such as disk space, from an extensive network of underlying physical servers. If one server goes
offline it will have no effect on availability, as the virtual servers will continue to pull resources from the remaining
network of servers.
Physical Security: The underlying physical servers are still housed within data centers and so benefit from the security
measures that those facilities implement to prevent people from accessing or disrupting them on-site.
Outsource Management: When you are managing the business, Someone else manages your computing infrastructure.
You do not need to worry about management as well as upgradation.

To more clarification about how cloud computing has changed the commercial deployment of
the system. Consider below examples:
Amazon Web Services(AWS): One of the most successful cloud-based businesses is Amazon
Web Services(AWS), which is an Infrastructure as a Service(Iaas) offering that pays rent for
virtual computers on Amazon’s infrastructure.
Microsoft Azure Platform: Microsoft is creating the Azure platform which enables the .NET
Framework Application to run over the internet as an alternative platform for Microsoft
developers. This is the classic Platform as a Service(PaaS).

Types of Cloud
Public cloud
Private cloud
Hybrid cloud
Community cloud

Public Cloud
• Public clouds are managed by third parties which provide cloud services over the internet to
the public, these services are available as pay-as-you-go billing models.
• They offer solutions for minimizing IT infrastructure costs and become a good option for
handling peak loads on the local infrastructure. Public clouds are the go-to option for small
enterprises, which can start their businesses without large upfront investments by completely
relying on public infrastructure for their IT needs.
• The fundamental characteristics of public clouds are multitenancy. A public cloud is meant
to serve multiple users, not a single customer. A user requires a virtual computing
environment that is separated, and most likely isolated, from other users.

Private cloud
Private clouds are distributed systems that work on private infrastructure and provide the users
with dynamic provisioning of computing resources. Instead of a pay-as-you-go model in private
clouds, there could be other schemes that manage the usage of the cloud and proportionally
billing of the different departments or sections of an enterprise. Private cloud providers are HP
Data Centers, Ubuntu, Elastic-Private cloud, Microsoft, etc.

The advantages of using a private cloud are as follows:
Customer information protection: In the private cloud security concerns are less since customer
data and other sensitive information do not flow out of private infrastructure.
Infrastructure ensuring SLAs: Private cloud provides specific operations such as appropriate
clustering, data replication, system monitoring, and maintenance, disaster recovery, and other
uptime services.
Compliance with standard procedures and operations: Specific procedures have to be put in
place when deploying and executing applications according to third-party compliance standards.
This is not possible in the case of the public cloud.
Disadvantages of using a private cloud are:
The restricted area of operations: Private cloud is accessible within a particular area. So the
area of accessibility is restricted.
Expertise requires: In the private cloud security concerns are less since customer data and other

Hybrid cloud:
A hybrid cloud is a heterogeneous distributed system formed by combining facilities of the
public cloud and private cloud. For this reason, they are also called heterogeneous clouds.
A major drawback of private deployments is the inability to scale on-demand and efficiently
address peak loads. Here public clouds are needed. Hence, a hybrid cloud takes advantage of
both public and private clouds.
Advantages of using a
Hybrid cloud are:
1) Cost : Available in cheap
cost than other clouds because
it is formed by distributed
system.
2) Speed : It is efficiently fast
with lower cost, It reduces
latency of data transfer
process.
3) Security : Most important
thing is security. Hybrid cloud

Community cloud:
Community clouds are distributed systems created by integrating the services of different clouds
to address the specific needs of an industry, a community, or a business sector. But sharing
responsibilities among the organizations is difficult.
In the community cloud, the infrastructure is shared between organizations that have shared
concerns or tasks. The cloud may be managed by an organization or a third party.

Sectors that use community clouds are:
1. Media industry: Media companies are looking for quick, simple, low-cost ways for
increasing the efficiency of content generation. Most media productions involve an
extended ecosystem of partners. In particular, the creation of digital content is the
outcome of a collaborative process that includes the movement of large data, massive
compute-intensive rendering tasks, and complex workflow executions.
2. Healthcare industry: In the healthcare industry community clouds are used to share
information and knowledge on the global level with sensitive data in the private
infrastructure.
3. Energy and core industry: In these sectors, the community cloud is used to cluster
a set of solution which collectively addresses the management, deployment, and
orchestration of services and operations.
4. Scientific research: In this organization with common interests in science share a
large distributed infrastructure for scientific computing.

Infrastructure as a Service (IaaS)
IaaS is also known as Hardware as a Service (HaaS). It is a computing infrastructure
managed over the internet. The main advantage of using IaaS is that it helps users to
avoid the cost and complexity of purchasing and managing the physical servers.
Characteristics of IaaS
There are the following characteristics of IaaS -
Resources are available as a service
Services are highly scalable
Dynamic and flexible
GUI and API-based access
Automated administrative tasks
Example: DigitalOcean, Linode, Amazon Web Services (AWS), Microsoft Azure,
Google Compute Engine (GCE), Rackspace, and Cisco Metacloud.

IaaS Suitability
● IaaS, as the name suggests, is a way of providing Cloud computing
infrastructure such as virtual machines, storage drives, servers, operating
systems & networks, which is also an on-demand service like that of SaaS.
● Rather than purchasing servers or developing software, clients buy those
resources as a fully outsourced service based on their requirements.
● "Public cloud" is considered as an infrastructure that consists of shared
resources, based on a self-service over the Internet.
● It is the only layer of the cloud where the customer gets the platform for
their organization to outsource IT infrastructure on a pay-per-use basis.
● Who uses IaaS?
Companies of different sizes prefer IaaS solutions. For example, startups and small businesses can stick to it to avoid
spending money and time on purchasing or creating software and hardware. At the same time,

Pros and Cons of IaaS
Advantages of IaaS are:
● Dynamic: Users can dynamically opt & configure devices such as CPU, storage drive, etc.
● Easy Access: Users can easily access the vast cloud computing power.
● Renting: Flexible and efficient while renting IT infrastructures.
● Full control of computer resources along with portability.

● Advantages of IaaS:
There are the following advantages of IaaS computing layer -
● 1. Shared infrastructure
IaaS allows multiple users to share the same physical
infrastructure.
● 2. Web access to the resources
Iaas allows IT users to access resources over the internet.
● 3. Pay-as-per-use mode
IaaS providers provide services based on the pay-as-per-use
basis. The users are required to pay for what they have used.

● 4. Focus on the core business
IaaS providers focus on the organization's core business
rather than on IT infrastructure.
● 5. On-demand scalability
On-demand scalability is one of the biggest advantages of
IaaS. Using IaaS, users do not worry about to upgrade software
and troubleshoot the issues related to hardware components.

Cons of IaaS:
● Internet connection is a must.
● IaaS depends on virtualization services.
● This service restricts user-privacy & customization.

● Disadvantages of IaaS
● 1. Security:
Security is one of the biggest issues in IaaS. Most of the
IaaS providers are not able to provide 100% security.
● 2. Maintenance & Upgrade
Although IaaS service providers maintain the software, but
they do not upgrade the software for some organizations.
● 3. Interoperability issues
● It is difficult to migrate VM from one IaaS provider to the other,
so the customers might face problem related to vendor lock-in.

● IaaS provider provides the following services -
1. Compute: Computing as a Service includes virtual central
processing units and virtual main memory for the Vms that
is provisioned to the end- users.
2. Storage: IaaS provider provides back-end storage for
storing files.
3. Network: Network as a Service (NaaS) provides networking
components such as routers, switches, and bridges for the
Vms.
4. Load balancers: It provides load balancing capability at the
infrastructure layer.

IaaS Service Providers
The full list of top ten IaaS examples is:
1. Amazon Web Services (AWS)
2. Digital Ocean
3. Microsoft Azure
4. Rackspace Open Cloud
5. Google Compute Engine
6. HP Enterprise Converged Infrastructure
7. IBM SmartCloud
8. Green Cloud Technologies
9. CloudStack
10. Linode
IaaS can be more efficient for companies than owning and managing their infrastructure. But this is only possible if the provider is reliable.

IaaS Solutions
1. Website hosting. Using IaaS solutions for running websites can be less expensive than traditional web
hosting.
2. Backup, recovery, and storage. IaaS requires no skilled staff to manage data, so it’s useful for handling
growing storage needs. It can also be used to manage recovery and backup systems.
3. Support for online applications (including networking options). Organizations can quickly deploy web
apps on IaaS when needed.
4. Testing and development operations. IaaS solutions make it easier to scale up test and development
environments.
5. Computing. This includes modeling, evaluating projects, and computer clustering.
6. Analysis of big data. This includes patterns, algorithms, and trends practice.

Platform as a Service (PaaS)
PaaS cloud computing platform is created for the programmer to develop, test, run, and
manage the applications.
Characteristics of PaaS
There are the following characteristics of PaaS -
Accessible to various users via the same development application.
Integrates with web services and databases.
Builds on virtualization technology, so resources can easily be scaled up or down as per
the organization's need.
Support multiple languages and frameworks.
Provides an ability to "Auto-scale".
Example: AWS Elastic Beanstalk, Windows Azure, Heroku, Force.com, Google App
Engine, Apache Stratos, Magento Commerce Cloud, and OpenShift.

Platform as a service (PaaS)
⮚ Platform as a service (PaaS) is a cloud computing model where a third-party provider
delivers hardware and software tools to users over the internet.
⮚ Usually, these tools are needed for application development. A PaaS provider hosts
the hardware and software on its own infrastructure
⮚ PaaS does not replace a company's entire IT infrastructure for software development. It
is provided through a cloud service provider's hosted infrastructure.
⮚ Users most frequently access the offerings through a web browser.
⮚ PaaS can be delivered through public, private and hybrid clouds to deliver services
such as application hosting and Java development.
⮚ Example: Google App Engine, Force.com, Joyent, Azure.

PAAS: Platform As A Service (PAAS) is a cloud delivery model for
applications composed of services managed by a third party.
It provides elastic scaling of your application which allows
developers to build applications and services over the internet
and the deployment models include public, private and hybrid.

● PaaS Services:
● PaaS offers IT infrastructure for software development within the whole application
lifecycle, including application building, testing and deployment. Other PaaS
services include:
• web service integration;
• information security;
• data management;
• analytics;
• business intelligence;
• database integration;
• artificial intelligence and machine learning;
• real-time communications.
● Users normally buy the services on a pay-as-you-go basis and access them over the
internet. Sometimes a flat monthly fee can be charged for using the PaaS platform.

Suitability of PaaS
● The cloud, and specifically PaaS, have significantly changed
how applications are developed, deployed, and managed. With
PaaS, applications can be delivered fast and without worrying
about the underlying infrastructure and software.
● However, PaaS is not for every application scenario. Before
switching to PaaS, you should consider its limitations so that
you can make an informed, strategic decision.
● PaaS can be a good choice as a part of a company’s digital
transformation initiative.

● Collaborative development: To increase the time to market and
developmentefficiency, there is a need for a common place where the
development team andother stakeholders of the application can
collaborate with each other.
● Automated testing and deployment: Automated testing and building of
anapplication are very useful while developing applications at a very
short timeframe.The automated testing tools reduce the time spent in
manual testing tools.

● Time to market: The PaaS services follow the iterative and
incrementaldevelopment methodologies that ensure that the application is
in the market as perthe time frame given.
● Frequent application migration: The major problem with PaaS services
arevendor lock-in. Since there are no common standards followed among
PaaSproviders, it is very difficult to migrate the application from one
PaaS provider tothe other.Customization at the infrastructure level: PaaS
is an abstracted service, and thePaaS users do not have full control over
the underlying infrastructure.

● Advantages of PaaS –
 Programmers need not worry about what specific database or
language the application has been programmed in.
 It offers developers the to build applications without the
overhead of the underlying operating system or infrastructure.
 Provides the freedom to developers to focus on the application’s
design while the platform takes care of the language and the
database.

Platform as a service (PaaS)- Advantages
1) Simplified Development
PaaS allows developers to focus on development and innovation without worrying about
infrastructure management.
2) Lower risk
No need for up-front investment in hardware and software.
Developers only need a PC and an internet connection to start building applications.
3) Prebuilt business functionality
Some PaaS vendors also provide already defined business functionality so that users can
avoid building everything from very scratch and hence can directly start the projects only.
4) Instant community
PaaS vendors frequently provide online communities where the developer can get the ideas
to share experiences and seek advice from others.
5) Scalability
Applications deployed can scale from one to thousands of users without any changes to the
applications

● Less coding time. In building a highly scalable application, developers often
need to write a piece of code to handle load balancing, caching, microservices,
and so on. With PaaS technology, such capabilities are available as an on-
demand service. Therefore, the programmers don’t have to constantly reinvent
the wheel (thereby increasing productivity).
● Faster time to market. PaaS automates and even eliminates some routine
tasks that every developer must perform in building their application. With a
platform-as-a-service model, a program can be created in less than a day
rather than weeks or months.
● Reduced costs. In traditional on-premises development, teams purchase and
manage the hardware and software necessary to build and run the application.
In a PaaS cloud model, the required computing resources are provided by a
third-party vendor usually on a pay-as-you-go basis or for a fixed monthly fee.
Therefore, the PaaS costs can be less, however, not in all cases.

Platform as a service (PaaS)- Disadvantages
1) Vendor lock-in
One has to write the applications according to the platform provided by the PaaS vendor, so
the migration of an application to another PaaS vendor would be a problem.
2) Data Privacy
Corporate data, whether it can be critical or not, will be private, so if it is not located within
the walls of the company, there can be a risk in terms of privacy of data.
3) Integration with the rest of the systems applications
It may happen that some applications are local, and some are in the cloud. So there will be
chances of increased complexity when we want to use data which in the cloud with the local
data.

● Security and compliance risks. PaaS software is generally offered in a public cloud where it is shared by multiple
users, which creates a higher risk of security vulnerabilities. It may not suit you if your application contains sensitive
data or you need to meet strict regulatory compliance requirements.
● Vendor dependence. Another downside of PaaS is vendor dependence. PaaS platforms are often designed as one-
size-fits-all solutions. Therefore, developers can be limited by the capabilities of the selected platform, such as
supported PaaS databases or programming languages. And, this brings us to the next disadvantage – service
availability.
● Service availability. With PaaS, you will be highly dependent on a single vendor since it provides and manages all the
hardware and software included in the platform. Therefore, you will have less control over the availability of your
application. Unexpected outages of your cloud provider can potentially cost you lost revenue, customers, and
productivity.
● To ensure high availability, it’s possible to use a failover mechanism in cloud computing. This technology enables
switching to the secondary backup component of the cloud system when the primary one fails through load
balancing, i.e. redistribution of workload across different vendors. However, in PaaS cloud computing, as it mentioned
above, developers are limited to the features of the chosen platform. So it can be difficult for them to create a custom
and reliable failover mechanism.

Platform as a service (PaaS) Providers

Software as a Service (SaaS)
SaaS is also known as "on-demand software". It is a software in which the
applications are hosted by a cloud service provider. Users can access these applications
with the help of internet connection and web browser.
Characteristics of SaaS
There are the following characteristics of SaaS -
Managed from a central location
Hosted on a remote server
Accessible over the internet
Users are not responsible for hardware and software updates. Updates are applied
automatically.
The services are purchased on the pay-as-per-use basis
Example: BigCommerce, Google Apps, Salesforce, Dropbox, ZenDesk, Cisco WebEx,
ZenDesk, Slack, and GoToMeeting.

There are various advantages and disadvantages of SaaS. The advantages are:
• Easy to buy: SaaS's cost is based on monthly or yearly fees allowing new organizations to
access the world of business at a low-cost, at least lesser than licensed application.
• Minimization of Hardware Requirement: All SaaS software is hosted remotely & so there is no
or lesser need for hardware for the organizations.
• Special Software: No special software versions are required, as all the users will use the same
software version. SaaS reduces IT costs by outsourcing hardware & software maintenance.
• Low Maintenance: SaaS removes the daily problem of installing, maintaining, and updating
software. The set-up cost of SaaS is also less in comparison to enterprise software.

Disadvantages are also the points that users and vendors must keep in mind while using the
SaaS:
• Latency factor: comes due to a variable distance of data between the cloud & the end-user, and
hence a possibility of latency may arise while interacting with applications.
• Internet Connection: is a major issue. Without an internet connection, SaaS applications are
unusable.
• Switching between SaaS vendors in case of any change is very difficult.
• The SaaS cloud service is not very secure as in-house deployment.

SaaS
● Software as a service (or SaaS) is a way of delivering applications over the Internet—as a service
● SaaS allows each user to access programs via the Internet, instead of having to install the software
on the user's computer.
● Method of software delivery that allows data to be accessed from any device with an internet connection and
a web browser.
Major characteristics
● The service is purchased on a user subscription basis.
● No additional hardware is required to be installed by the customer.
● Updates are applied automatically without customer intervention.

SaaS Pros and Cons
Cheaper upfront
SaaS is typically subscription-based (no licensing fees) there are lower costs upfront. SaaS exists in
the cloud, meaning hardware installation costs are completely eliminated. This makes SaaS
advantageous for startups.
Easy to implement
SaaS is already installed and configured in a cloud, so no need to worry about setting up the
infrastructure (which can get complicated). Implementation typically only involves registering and
either downloading a web browser extension or the application to your computer.

Difference between IaaS, PaaS, and SaaS

The Essential Characteristics of Cloud Computing are:
• On-demand self service
• Multi-tenancy and resource pooling
• Broad network access
• Rapid elasticity and scalability
• Resource pooling
• Measured and reporting service
• Automation
• Resilience
• Large Network Access
• Work from any location
• Comfortable payment structure
• Service Excellence
• Easy maintenance
• Flexibility
• Economical and Security

Ethical issues in cloud computing
Unauthorized access, data corruption, infrastructure failure, or unavailability are
some of the risks related to relinquishing the control to third party services;
moreover, it is difficult to identify the source of the problem and the entity causing
it.
Cloud computing is based on a paradigm shift with profound implications on
computing ethics.
The main elements of this shift are:
1. the control is relinquished to third party services;
2. the data is stored on multiple sites administered by several organizations; and
3. multiple services interoperate across the network.

Cloud Computing is Internet-based computing, where shared resources,
software, and information are provided to computers and other devices on
demand.
These are major issues in 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 to 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 cloud-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 users’ information with others. Security presents a real threat to
the cloud.
4. Higher Cost: If you want to use cloud services uninterruptedly then you need
to have a powerful network with higher bandwidth than 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 organizations, that restricts them from diving into cloud technology for
their business.

5. 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 to the service you almost hand over
your data into the hands of a third party.
If you are able to choose proper cloud service then in the
future you don’t need to worry about the recovery of lost
data in any contingency.

6.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, sometimes it becomes hard to decide how much should be charged in case the user
wants scalability and extend the services.
7. Lack of resources/skilled expertise: One of the major issues 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 rapid 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
employees need to grow. These challenges can only be minimized through additional

8. Pay-per-use service charges: Cloud computing services are on-demand services a
user can extend or compress the volume of the resource as per needs.
so you paid for how much you have consumed the resources. It is difficult to define a
certain pre-defined cost for a particular quantity of services.
Such types of ups and downs and price variations make the implementation of cloud
computing very difficult and intricate.
It is not easy for a firm’s owner to study consistent demand and fluctuations with the
seasons and various events.
So it is hard to build a budget for a service that could consume several months of the
budget in a few days of heavy use.

CLOUD VULNERABILITIES
Cloud vulnerabilities refer to the potential weaknesses or security gaps in cloud computing environments that can be exploited by
attackers. Here are some common cloud vulnerabilities:
1. Data Breaches:
 Unauthorized access to sensitive data stored in the cloud, often due to weak authentication, encryption, or inadequate security
policies.
2. Insecure APIs:
 Cloud services often expose APIs for user interactions. If these APIs are insecure, they can be exploited to compromise systems,
steal data, or cause service disruptions.
3. Misconfigured Cloud Settings:
 Misconfigurations, such as incorrect permissions or failure to encrypt sensitive data, can expose critical information to
unauthorized users.

4. Account Hijacking:
 Attackers can compromise cloud user accounts through phishing, social engineering, or weak passwords, giving
them unauthorized access to cloud services.
5. Insufficient Identity and Access Management (IAM):
 Poor management of user privileges, lack of multi-factor authentication (MFA), or over-permissive roles can lead to
unauthorized access.
6. Data Loss:
 Data in the cloud can be lost due to accidental deletion, malicious attacks (such as ransomware), or failure to back
up data properly.
7. Denial of Service (DoS) Attacks:
 Cloud systems can be overwhelmed by DoS attacks, making services unavailable to legitimate users.

8. Shared Technology Vulnerabilities:
 Cloud environments often share infrastructure, platforms, and applications. Vulnerabilities in shared components can
result in "cross-tenant" attacks, where one user's compromise affects others.
9. Malicious Insiders:
 Employees or contractors with access to cloud systems could intentionally or unintentionally cause harm by leaking
data or damaging cloud resources.
10. Inadequate Security Controls:
 Some cloud service providers may not implement sufficient security controls, leaving customer data vulnerable to
attacks.

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