Cloud Computing

Prof. Rajesh Kumar Panda, KIIT University

Cloud Computing


What is cloud computing

• Cloud computing is a model for enabling ubiquitous, 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.


• The cloud isn’t a technology.• It’s more of an approach to building IT services• An approach that harnesses the power of

servers, as well as virtualization technologies that combine servers into large computing pools and divide single servers into multiple virtual machines.

• The term “Cloud” is analogical to “Internet”.


• Cloud computing is internet based computing where virtual shared servers provide software, infrastructure, platform, devices and other resources and hosting to customers on a pay-as-you-use basis.

• Cloud computing customers do not own the physical infrastructure.

• They rent the usage from a third party provider


Characteristics

• Location Independent Resource Pooling• Measured Service• Rapid Elasticity• On Demand Self Service• Broad Network Access• Low cost


Cloud Architecture

Virtualized resources

Compute Networking

Storage

OS

Hardware

Application

Platform

Infrastructure

Basic middleware(database services , application server )

Developments tools

Services and built in functionality



Service Models

http://en.wikipedia.org/wiki/File:Cloud_computing_layers.png


Software as a Service(SaaS)

• SaaS is a model of software deployment where an application is hosted as a service provided to customers across the Internet.

• Saas alleviates the burden of software maintenance/support– but users relinquish control over software versions and

requirements.



SaaS Examples



Platform as a Service (PaaS)

• PaaS provides all of the facilities required to support the complete life cycle of building and delivering web applications and services entirely from the Internet.

– Typically applications must be developed with a particular platform in mind

–Multi tenant environments– Highly scalable multi tier architecture



PaaS Examples


Infrastructure as a Service(IaaS)

• IaaS is the delivery of technology infrastructure as an on demand scalable service

• Provide processing, storage, network capacity, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software.

– Usually billed based on usage– Usually multi tenant virtualized environment– Can be coupled with Managed Services for OS and

application support



IaaS Examples


Deployment Models

The four primary types of cloud deployment models are:

• Public• Private• Hybrid• Community



• Public Cloud A public cloud is a cloud computing model in which services, such as applications and storage, are available for general use over the Internet. Public cloud services may be offered on a pay-per-usage mode or other purchasing models. An example of a public cloud is IBM’s Blue Cloud.

• Private CloudA private cloud is a virtualized data center that operates within a firewall. Private clouds are highly virtualized, joined together by mass quantities of IT infrastructure into resource pools, and privately owned and managed.

• Hybrid CloudA hybrid cloud is a mix of public and private clouds.

• Community CloudA community cloud is an infrastructure shared by several organizations which supports a specific community.



Advantages

• Simplicity – easy to deploy and use• Pay as you use – pay only for the services you

consume• Cost saving – Lesser in-house IT costs• Scalability• Backup and Recovery• Easy to upgrade• On demand availability



Challenges

• Security• Performance• Uninterrupted availability• Integration with in-house IT• Ability to customize to internal needs• Migrating back to in-house• Regulatory requirements prohibit cloud (data

storage abstracted)



Documents

Cloud Computing