Cloud computing relies on sharing computing resources over a network rather than local devices. It has evolved from mainframes to client-server models to today's cloud systems. The cloud is characterized by on-demand self-service, broad network access, resource pooling, rapid elasticity, and measured service. There are several cloud service models including Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). Cloud computing provides green benefits such as reduced hardware, energy usage, and emissions through server consolidation and virtualization.

1. Cloud Computing
2012/2013

2. Outline
• Introduction
• History
• The nature of the cloud
• The cloud elements
• Green benefits of Cloud Computing
• Conclusion

3. What is cloud computing ?
Cloud computing is a type of computing that relies
on sharing computing resources rather than having
local servers or personal devices to handle
applications.
1
Introduction

4. History of Computing
Mainframe
Client Server
Minicomputer
Cloud
Web
Virtualization
1960 1970 1980 1990 2000 2

5. The nature of the cloud
On-demand self-service A consumer can provision computing capabilities :server time and network
storage, as needed and automatically.
Broad network access Capabilities are available over the network and accessed through standard
mechanisms that promote use by heterogeneous thin or thick client
platforms (e.g., mobile phones, laptops, and PDAs).
Resource pooling The provider’s computing resources are pooled to serve multiple consumers
using a multi-tenant model, with different physical and virtual resources
dynamically assigned and reassigned according to consumer demand.
Rapid elasticity Capabilities can be rapidly and elastically provisioned.
To the consumer, the capabilities available for provisioning often appear to
be unlimited and can be purchased in any quantity at any time.
Measured service Cloud systems automatically control and optimize resource use by leveraging
a metering capability
3

6. Cloud elements
Management & Administration
Software as a service
Plateforme as a service
Infrastructure as a service
Cloud service delivery models
4

7. SaaS
Where off-the shelf applications
Are accessed over the internet
• Free or paid via subscription
• Accessible via any computer
• Facilitate collaborative working
• Generic application not always suitable
for business use …
Software as a service
5

8. examples
Office Apps: Word Processors, Spreadsheets and Presentation Packages
Google Docs Zoho SlideRocket
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9. PaaS
Provide environment and tools
for creating new applications
• Rapid development at low coast
• Private or public deployment
• Limits developers to provide languages
and tools
Platform as a service
7

10. examples
Platform as a Service (PaaS) Vendors :
Google App Engine Windows Azure Salesforce
8

11. IaaS
Allows existing applications to be
run on a cloud supplier’s hardware
Infrastructure as a service
IaaS Categories:
9

12. private cloud •The customer rents a number of co-located servers in part
of a data center,
•The cloud hardware is as separated from the cloud of
other users,
• The most secure form of IaaS.
dedicated
hosting
• The customer rents dedicated physical servers on demand
from anywhere,
• Less costly than a private cloud,
•dedicated hosting can be dynamically scaled.
The customer is able to increase or decrease the number
of servers.
hybrid hosting •The customer rents on demand a mix of dedicated physical
servers and some less expensive virtual server instances.
cloud hosting • The customer rents virtual server instances required on
demand.
Customers share all his servers with other customers.
10

13. examples
IaaS Providers:
Amazon Web Services GoGrid Elastic Hosts
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14. Cloud elements
Public Private Hybrid
Deployment
Models
Service
Models
Software as a
Service (SaaS)
Platform as a
Service (PaaS)
Infrastructure as a
Service (IaaS)
Essential
Characteristics On-Demand
Self Service
Broad Network
Access
Resource Pooling
Rapid ElasticityMeasured Service
Community
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15. Green benefits of Cloud Computing
Servers  Reduce the number of servers : 5 to 10 virtual servers to 1 physical server
 Less space required
 Reduced power
 More energy efficient servers
Workstations  Thin clients -> reduced power ,
 Virtual workstations running on servers : 30 to 70 wks to 1 server
IT Support  Workstations that are not used are switched off,
 Maintenance performed real time.
Environmental  Lower carbon emissions : less power needed
 Recycle old equipment
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16. Conclusion
• Clouds
 Provide internet based services
 Available on demand
 And fully managed by the provider
 There is no one “Cloud”. There are many models and
architectures
• Clouds let you
 Avoid capital expenses on hardware, software, and service
 Share infrastructure and costs
 Lower management overhead
 Access a large range of apps

17. • http://e-university.wisdomjobs.com/cloud-computing
• http://www.webopedia.com/TERM/C/cloud_computi
ng.html
• http://csrc.nist.gov/publications/nistpubs/800-
145/SP800-145.pdf
• http://technet.microsoft.com/en-
us/magazine/hh509051.aspx
References

18. Thank you for your attention