What are the Services?

The cloud model is composed of three service models: Software as a Service (SaaS), Platforms as a Service (PaaS), and Infrastructure as a Service (IaaS). This graphic displays how the different types of cloud services are geared for different purposes:

Cloud Services

Here is the NIST definition for each service model and examples for each:

Software as a Service (SaaS) -- 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.

Examples:

  • Gov-Apps, Internet Services
  • Blogging/Surveys/Twitter, Social Networking
  • Information/Knowledge Sharing (Wiki)
  • Communication (e-mail), Collaboration (e-meeting)
  • Productivity Tools (office)
  • Enterprise Resource Planning (ERP)


Platform as a Service (PaaS) -- 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.

Examples:

  • Application Development, Data, Workflow, etc.
  • Security Services (Single Sign-On, Authentication, etc.)
  • Database Management
  • Directory Services


Infrastructure as a Service (IaaS) -- 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).

Examples:

  • Mainframes, Servers, Storage
  • IT Facilities/Hosting Services