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.(byNIST)

“an Internet based computing paradigm that delivers on-demand software and hardware computing capability as a ‘service’ through virtualization where the end user is completely abstracted from the computing resources”

3-4-5 Rule

3 : Services

4 : Deployment Models

5 : Characteristics

3 : Services

1. IaaS (Infrastructure as a Service)

The capability provided to the consumer is to provision processing, storage, networks, and other fundamental computing resources where the consumer is able to deploy and run arbitrary software, which can include operating systems and applications. The consumer does not manage or control the underlying cloud infrastructure but has control over operating systems, storage, deployed applications, and possibly limited control of select networking components (e.g., host firewalls)

2. PaaS (Platform as a Service)

The capability provided to the consumer is to deploy onto the cloud infrastructure consumer-created or acquired applications created using programming languages and tools supported by the provider. The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, or storage, but has control over the deployed applications and possibly application hosting environment configurations

Windows Azure, Google App Engine, Hadoop, etc. are some well-known PaaS platforms

3. SaaS (Software as a Service)

The capability provided to the consumer is to use the provider's applications running on a cloud infrastructure. The applications are accessible from various client devices through a thin client interface such as a web browser (e.g., web-based email). The consumer does not manage or control the underlying cloud infrastructure including network, servers, operating systems, storage, or even individual application capabilities, with the possible exception of limited user-specific application configuration settings

Moto: “No Software”

Ex: Salesforce.com for CRM, Google Docs for document sharing, and web email systems like Gmail, Hotmail, and Yahoo! Mail

Cloud Service Models