This paradigm is more than just a theory; there are multiple cloud computing providers today. And the number of providers will most probably grow as people start seeing greater savings and work to reduce adoption barriers starts showing results.
Cloud computing environments can be public (offered as a service, typically for a fee) or private (deployed behind an organization’s firewall). The most common cloud computing environments take the form of infrastructure-as-a-service (IaaS), platform-as-a-service (PaaS), or software-as-a-service (SaaS).
In IaaS environments
- Computational infrastructure is available over the Internet (e.g., compute, storage, and so on).
- A variety of interfaces facilitate interaction.
- Services are provided on top of the infrastructure.
- Feature application development platforms
- Allow developers to leverage the resources of established organizations to create and host applications of a larger scale than an individual or small business would be able to handle
- Feature application-specific capabilities (e.g., a service that provides customer management)
- Allow organizations and developers to use business-specific capabilities developed by third parties. Examples of third-party business specific capabilities are
- Force.com, which is provided by salesforce.com (the SaaS leader) to give enterprise users a platform to build and run applications and components bought from AppExchange or custom applications
- Zoho, which provides a large suite of web-based applications, mostly for enterprise use