Nowadays everybody is talking about Cloud so I thought to write a very basic blog about Cloud. Cloud computing provides new tools for the organizations for addressing the changing business needs by providing them with very valuable and effective architectural, delivery, and sourcing options.
The cloud provides options for approach, sourcing, and control. It delivers a well-defined set of services, which are perceived by the customers to have infinite capacity, continuous availability, increased agility, and improved cost efficiency. Cloud options typically are categorized by the following service models:
- Software as a Service (SaaS)
Software as a Service delivers business processes and applications, such as CRM, collaboration, and e-mail, as standardized capabilities for a usage-based cost at an agreed, business-relevant service level. SaaS provides significant efficiencies in cost and delivery in exchange for minimal customization and represents a shift of operational risks from the consumer to the provider. All infrastructure and IT operational functions are abstracted away from the consumer.
- Platform as a Service (PaaS)
Platform as a Service delivers an application execution services, such as application runtime, storage, and integration, for applications written for a pre-specified architectural framework. PaaS provides an efficient and agile approach to operate scale-out applications in a predictable and cost-effective manner. Service levels and operational risks are shared because the consumer must take responsibility for the stability, architectural compliance, and overall operations of the application while the provider delivers the platform capability (including the infrastructure and operational functions) at a predictable service level and cost.
- Infrastructure as a Service (IaaS)
Infrastructure as a Service abstracts hardware (server, storage, and networking infrastructure) into a pool of computing, storage, and connectivity capabilities that are delivered as services for a usage-based cost. Its goal is to provide a flexible, standard, and virtualized operating environment that becomes a foundation for PaaS and SaaS.
IaaS is usually seen to provide a standardized virtual server. The consumer takes responsibility for configuration and operations of the guest Operating System (OS), software, and Database(DB). Compute capabilities (such as performance, bandwidth, and storage access) are also standardized. Service levels cover the performance and availability of the virtualized infrastructure. The consumer takes on the operational risk that exists above the infrastructure.