1. Cloud Architecture

2. SPI Model Cloud Computing Classification Model – SPI Cloud Computing Classification Model – SPI - SaaS: (Software as a Service) - SaaS: (Software as a Service) - PaaS (Platform as a Service) - PaaS (Platform as a Service) - IaaS (Infrastructure as a Service) - IaaS (Infrastructure as a Service)

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4. Infrastructure services share the physical hardware Infrastructure services share the physical hardware Platform services share the application framework Platform services share the application framework Software services share the entire software stack. Software services share the entire software stack.

5. Amazon Elastic Compute Cloud (EC2) is a classic example of IaaS Amazon Elastic Compute Cloud (EC2) is a classic example of IaaS Google App Engine is generally considered to be a PaaS Google App Engine is generally considered to be a PaaS Salesforce.com is a well known example of SaaS. Salesforce.com is a well known example of SaaS.

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12. Cloud Delivery Model Public Cloud Public Cloud Private Cloud Private Cloud Partner Cloud Partner Cloud Community Cloud Community Cloud Hybrid or Multi-sourced Delivery Hybrid or Multi-sourced Delivery

13. Public cloud: It has large set of the following features: Public cloud: It has large set of the following features: - Off-premise - Off-premise - Elastisity - Elastisity - Flexible billing - Flexible billing - Virtualization - Virtualization - Service delivery - Service delivery - Universal access - Universal access - Simplified management - Simplified management - Affordable resources - Affordable resources - Multi-tenancy - Multi-tenancy - Service level management - Service level management

14. Private Cloud: only leverages some of the aspects of cloud computing Private Cloud: only leverages some of the aspects of cloud computing - hosted on-premise, - hosted on-premise, - scales “only” into the hundreds or perhaps thousands of nodes, - scales “only” into the hundreds or perhaps thousands of nodes, - connected primarily to the using organization through private network links. - connected primarily to the using organization through private network links. - since all applications and servers are shared within the corporation the notion of multi- tenancy is minimized. - since all applications and servers are shared within the corporation the notion of multi- tenancy is minimized.

15. Copyright © 2012, Elsevier Inc. All rights reserved. 2 - 15 Public Clouds vs. Private Clouds : Characterist ics Public cloudsPrivate clouds Technology leverage and ownership Owned by service providers Leverage existing IT infrastructure and personnel; owned by individual organization Management of provisioned resources Creating and managing VM instances within proprietary infrastructure; promote standardization, preserves capital investment, application flexibility Client managed; achieve customization and offer higher efficiency Workload distribution methods and loading policies Handle workload without communication dependency; distribute data and VM resources; surge workload is off-loaded Handle workload dynamically, but can better balance workloads; distribute data and VM resources Security and data privacy enforcement Publicly accessible through remote interface Access is limited; provide pre- production testing and enforce data privacy and security policies Example platforms Google App Engine, Amazon AWS, Microsoft Azure IBM RC2

16. Partner Cloud: Large IT providers, such as HP Enterprise Services or IBM Global Services, run data center for operations for large customers Partner Cloud: Large IT providers, such as HP Enterprise Services or IBM Global Services, run data center for operations for large customers - manage services in their own facilities; - manage services in their own facilities; - or on customer premises; - or on customer premises; - or on property of a third party - or on property of a third party

17. Community Cloud: it caters a group of organizations with common set of requirements or objectives. Community Cloud: it caters a group of organizations with common set of requirements or objectives. The most prominent examples are government clouds that are open to federal and municipal agencies. The most prominent examples are government clouds that are open to federal and municipal agencies.

18. Hybrid or Multi-sourced delivery: Hybrid or Multi-sourced delivery:

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20. Cloud and Open Source Cloud computing can leverage open source in many ways. Cloud computing can leverage open source in many ways. - Self-supported Linux is by far the most popular opernating system from infrastructure servies - Self-supported Linux is by far the most popular opernating system from infrastructure servies - Cloud provider often use Xen and KVM for virtualization - Cloud provider often use Xen and KVM for virtualization - Distributed cloud framwworks, such as Hadoop, are usally open source - Distributed cloud framwworks, such as Hadoop, are usally open source - Web-based API make the client device less relevant, which can reduce desktop license fees by adopting Linux, Google Chrome or other open- souce client. - Web-based API make the client device less relevant, which can reduce desktop license fees by adopting Linux, Google Chrome or other open- souce client. - Many SaaS solutions leverage open-source software, such as SugarCRM