Cloud computing

1. Cloud Computing
Elective
Suman Sharma
Asst. Prof. IOE Pulchowk Campus
suman.sharma@ioe.edu.np
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2. Chapter Overview
1. Introduction
2. Cloud Service Models
3. Building Cloud Networks
4. Security in Cloud Computing
• Cloud Computing: Implementation Management and Security, John W. Rittinghouse and James F.
Ransome (Recommended for Unit 1, 2, 3 4)
• Cloud Application architecture, George Reese (Recommended for Unit 4)
• Cloud Computing for Dummies, Judith Hurwitz, Robin Bloor, Marcia Kaufman, Fern
Halper(Recommended for Unit 3)
• Handbook of cloud computing, Borko Furht, Armando Escalante (Recommended for Unit 1)
• Cloud Computing and SOA Convergence in your Enterprise, a step by step guide, David S. Linthicum
(Recommended for Unit 1, 2, 3)
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3. Chapter 1
Introduction
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4. Introduction of Cloud Computing
• Defining the Cloud
• The Emergence of Cloud Computing
• Cloud-Based Services
• Grid Computing or Cloud Computing
• Components of Cloud Computing
• Virtualization
• Cloud Computing Deployment Models (Types): Public, Private, Hybrid,
• Benefits of Using a Cloud Model
• Legal Issues in Using Cloud Models
• Characteristics of Cloud Computing
• Evolution of Cloud Computing
• Challenges for the Cloud computing
• Grid Computing
• Distributed Computing in Grid and Cloud.
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5. Definition of Cloud Computing
• Cloud computing refers to logical computational resources accessible via
a computer network.
• Cloud computing is a model for enabling convenient, on-demand
network access to a shared pool of configurable computing resources
(e.g., networks, servers, storage, applications, and services) that can be
rapidly provisioned and released with minimal management effort or
service provider interaction.
Examples: Google cloud, Microsoft 365, Slack etc.
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6. 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
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7. 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.
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8. Characteristics of Cloud Computing
• Agility
• High availability and reliability
• High Scalability
• Multi-Sharing
• Device and Location Independence
• Maintenance
• Low Cost
• Services in the pay-per-use mode
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9. Advantages of Cloud Computing
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10. Disadvantages of Cloud Computing
• Internet Connectivity
• Vendor lock-in
• Limited Control
• Security
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11. 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.
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12. On the basis of above computing, there was emerged of cloud computing
concepts that later implemented.
• Joseph Carl Robnett Licklider in 1960s
• 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.
• 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.
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13. • 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.
• Microsoft launched Windows Azure, and
companies like Oracle and HP have all joined
the game. This proves that today, cloud
computing has become mainstream.
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14. Cloud Service Models:
There are the following three types of
cloud service models:
1. Infrastructure as a Service (IaaS)
2. Platform as a Service (PaaS)
3. Software as a Service (SaaS)
Cloud Models
Service Model Deployment Model
• Public
• Private
• Hybrid
• Community
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15. Infrastructure as a Service (IaaS)
• Infrastructure as a service (IaaS) is also
known as Hardware as a service (HaaS)
Characteristics of IaaS
• Resources are available as a service
• Services are highly scalable
• Dynamic and flexible
• GUI and API-based access
• Automated administrative tasks
Advantages:
• Cost
• Website hosting
• Security
• Maintenance 15

16. 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
• 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.
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17. Advantages:
• Simplified Development
• Lower risk
• Prebuilt business functionality
• Instant community
• Scalability
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18. 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
• 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
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19. Advantages:
• SaaS is easy to buy
• One to Many
• Less hardware required for SaaS
• Low maintenance required for SaaS
• No special software or hardware versions required
• Multi-device support
• No client-side installation
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20. IaaS Paas SaaS
It provides a virtual data
center to store information
and create platforms for
app development, testing,
and deployment.
It provides virtual platforms
and tools to create, test,
and deploy apps.
It provides web software and
apps to complete business
tasks.
It provides access to
resources such as virtual
machines, virtual storage,
etc.
It provides runtime
environments and
deployment tools for
applications.
It provides software as a service
to the end-users.
It is used by network
architects.
It is used by developers. It is used by end users.
IaaS provides only
Infrastructure.
PaaS provides
Infrastructure+Platform.
SaaS provides
Infrastructure +Platform +Software.
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Comparison:

21. Evolution of Cloud Computing
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22. Evolution of Cloud Computing

23. Distributed computing
• Distributed computing is a model in which
components of a software system are shared
among multiple computers.
• Even though the components are spread out
across multiple computers, they are run as one
system. This is done in order to improve
efficiency and performance.
• In a narrow form, distributed computing is
limited to programs with components shared
among computers within a limited geographic
area.
• Broader definitions, however, include shared
tasks as well as program components.
• In the broadest sense of the term, distributed
computing just means that something is shared
among multiple systems, which may also be in
different locations.
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24. • Hardware and software architectures are used to maintain a
distributed system.
• Everything must be interconnected
• CPUs via the network and processes via the communication system.
Types of distributed systems
• Distributed systems generally fall into one of four different basic
architecture models:
• Client-server
• Three-tier
• n-tier
• Peer-to-peer
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25. Grid Computing
• Grid computing is also called as
"distributed computing."
• It links multiple computing resources
(PC's, workstations, servers, and
storage elements) together and
provides a mechanism to access
them.
• The main advantages of grid
computing are that it increases user
productivity by providing transparent
access to resources, and work can be
completed more quickly.
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26. Grid Computing Vs Cloud Computing
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Cloud Computing Grid Computing
Cloud Computing follows client-server computing
architecture.
Grid computing follows a distributed computing
architecture.
Scalability is high. Scalability is normal.
Cloud Computing is more flexible than grid
computing.
Grid Computing is less flexible than cloud
computing.
Cloud operates as a centralized management
system.
Grid operates as a decentralized management
system.
In cloud computing, cloud servers are owned by
infrastructure providers.
In Grid computing, grids are owned and
managed by the organization.
Cloud computing uses services like Iaas, PaaS,
and SaaS.
Grid computing uses systems like distributed
computing, distributed information, and
distributed pervasive.
Cloud Computing is Service-oriented. Grid Computing is Application-oriented.
It is accessible through standard web protocols. It is accessible through grid middleware.

27. Distributed vs Parallel Computing
• In parallel computing, all processors may have access to
a shared memory to exchange information between
processors.
• In distributed computing, each processor has its own private
memory (distributed memory). Information is exchanged by
passing messages between the processors.

28. Distributed vs Parallel Computing

29. Components in Cloud Computing
• Clients
• Datacenter
• Distributed Servers
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30. • Clients : End Users
• Mobile : Mobile includes PDA, Smartphones, or any other
portable devices which can access internet.
• Thin Clients : Now thin computers are that do not have
internal hard drives or very low internal configuration, but
rather the server do all there work and then display the
information.
• Thick Client : Regular computers, Devices that has own
capabilities to do some computing.

31. • Data Center
• Now datacentre is collection of server where application to
which you subscribe is housed,
• it could be a large room in basement, or room full of server
which you access through internet.
• Distributed Severs
• Server don't have to be housed in same location often
server are in dispersed geographically location but to you
the cloud subscriber, these server acts if they are humming
right away next to each other.
• This gives the service provider more flexibility in option and
security.

32. Cloud Computing Architecture
• As 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
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33. 33
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.

34. Virtualization
• Virtualization is the "creation of a virtual (rather than actual) version of
something, such as a server, a desktop, a storage device, an operating
system or network resources".
• In other words, 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.
• The machine on which the virtual machine is going to create is known
as Host Machine and that virtual machine is referred as a Guest
Machine
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35. Types of Virtualization
1. Hardware Virtualization.
2. Operating system Virtualization.
3. Server Virtualization.
4. Storage Virtualization.
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36. Deployment models:
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37. Cloud Computing Deployment models

38. Public Cloud
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Public cloud is open to all to
store and access information
via the Internet using the pay-
per-usage method.
In public cloud, computing
resources are managed and
operated by the Cloud Service
Provider (CSP).

39. Private Cloud
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• Private cloud is also known as an internal
cloud or corporate cloud.
• It is used by organizations to build and
manage their own data centers internally or
by the third party.
• It can be deployed using Opensource tools
such as Openstack and Eucalyptus.
• Based on the location and management,
National Institute of Standards and
Technology (NIST) divide private cloud into
the following two parts-
•On-premise private cloud
•Outsourced private cloud

40. Hybrid Cloud
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• Hybrid Cloud is a combination of the public cloud
and the private cloud.
Hybrid Cloud = Public Cloud + Private Cloud
• Hybrid cloud is partially secure because the
services which are running on the public cloud can
be accessed by anyone, while the services which
are running on a private cloud can be accessed
only by the organization's users.
Example: Google Application Suite (Gmail, Google
Apps, and Google Drive), Office 365 (MS Office on
the Web and One Drive), Amazon Web Services.

41. Community Cloud
• Community cloud allows systems and
services to be accessible by a group
of several organizations to share the
information between the
organization and a specific
community.
• It is owned, managed, and operated
by one or more organizations in the
community, a third party, or a
combination of them.
• Example: Health Care community
cloud
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42. Cloud Ecosystem

43. Cross Border Legal Issues
• Cloud Cloud inherently being stateless and serves located in different locations and countries
creates issues related to conflict of laws, applicable law and jurisdiction.
• Cross-border data flow, potentially conflicting regulations, applicable regulations.
Involvement of multiple parties
• Cloud services usually involve multiple parties which makes onus and liability shift on one
another. Liability and responsibility of sub-contractors is often limited or disclaimed in entirety.
• Contractual private lacks between the parties which makes it difficult for the client to bind a
provider for a breach.
• Agreements should include liability of provider for acts of sub-contractor.
• Right to conduct due diligence and to understand the model of delivery of services should be
given to the customer.
Cloud Computing: Legal issues and Challenges

44. Privacy and Security
• Multi-tenant architecture
• Data from different user are usually stored on a single virtual server
• Multiple virtual servers run on a single physical server
• Data security depends upon the integrity of the virtualization
Service Level Agreements
• Cloud services are usually provided on standard service level agreements which
are usually non-negotiable.
• Even if negotiation is not agreeable for SLA, higher degree of reporting should be
integrated in the agreement.
• Additional options for termination should be provided.

45. Audit Trail
• As data is on continuous move and flow in the cloud services, client should have the right to know
where and by whom its data is stored, accessed, transferred and altered.
• Confirm whether the vendor provides the audit trails rights or not.
Exit Issues
• In case a user has to change provider in the future the options for portability and
interoperability are critical issues to be considered.
• In case of exit can the records be successfully accessed?
• Can data be extracted from the cloud?
• Obligations of each party in case of exit.

46. Thank You
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47. Questions related to chapter 1
1. Explain the cloud computing model and its benefits. What are the
challenges in cloud computing?
2. Explain the cloud deployment models.
3. What are the difference between public clouds and private clouds?
4. Explain platform-as-a-service and its challenges.
5. Describe about cloud based services.
6. How grid computing differs from cloud computing?
7. What do you mean by virtualization? What is the role of virtualization in
cloud computing?
8. How can you define cloud service? Describe the characteristics of a cloud
service.
9. Differentiate between each of the private, public and hybrid cloud
models with suitable examples.
10. Explain the evolution of Cloud computing.
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