Cloud Computing

Cloud Computing has emerged as the new industry buzzword.Cloud Computing allows users to tap into a

virtually unlimited pool of computing resources over the Internet (the Cloud).
Unlike traditional IT, Cloud users have little insight or control over the underlying
infrastructure, and they must interact with the Cloud via an API provided by the
Cloud vendors. The most exciting part of the Cloud, however, is its elasticity and
utility-style pricing. Users can provision resources dynamically in a self-service
manner and pay only for what they use – much like how we use utilities like
electricity or water.

CLOUD ANTI VIRUS IS LATEST TREND IN CLOUD COMPUTING

What Is Cloud Computing?

• Computing resources residing on
Internet (‘the cloud’)
• Underlying physical resources not
exposed
– Abstracted at various levels (virtual
machines, database as a service, etc.)
– No direct hardware control
• Infinitely scalable
• Billed by consumption
– Per hour, per GB, etc.
• Typical Interface: Web Services
– REST, SOAP

• Quick, Self-Service Provisioning
– Developers no longer waiting on IT to respond
– Eases and Speeds Up Application Development
• Elastic
– Scale up and down rapidly





Different Levels of Cloud Computing
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Cloud computing is typically divided into three levels of service offerings:
Software as a Service(SaaS),
Platform as a Service (PaaS), and
Infrastructure as a service (IaaS).
These levels support
virtualization and management of differing levels of the solution stack.

Software as a Service
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A SaaS provider typically hosts and manages a given application in their own data center and makes it available to multiple tenants and users over the Web. Some SaaS providers run on another cloud provider’s PaaS or IaaS service offerings. Oracle CRM On Demand,Salesforce.com, and Netsuite are some of the well known SaaS examples.

Platform as a Service
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Platform as a Service (PaaS) is an application development and deployment platform delivered as a service to developers over the Web. It facilitates development and deployment of applications without the cost and complexity of buying and managing the underlying infrastructure, providing all of the facilities required to support the complete life cycle of building and delivering web applications
and services entirely available from the Internet. This platform consists of infrastructure software, and typically includes a database, middleware and development tools. A virtualized and clustered grid computing architecture is often the basis for this infrastructure software. Some PaaS offerings have a specific programming language or API. For example,Google AppEngine is a PaaS offering where developers write in Python or Java. EngineYard is Ruby on Rails. And sometimes PaaS providers have proprietary languages like force.com from Salesforce.com and Coghead, now owned by SAP.

Infrastructure as a Service
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Infrastructure as a Service (IaaS) is the delivery of hardware (server, storage and network), and associated software (operating systems virtualization technology, file system), as a service. It is an evolution of traditional hosting that does not require any long term commitment and allows users to provision resources on demand. Unlike PaaS services, the IaaS provider does very little management other than keep the data center operational and users must deploy and manage the software services
themselves – just the way they would in their own data center. Amazon Web Services Elastic Compute Cloud (EC2) and Secure Storage Service (S3) are examples of IaaS offerings.