Cloud 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. –NIST Definition of Cloud Computing. Version 15
On the technical side, the SaaS provider hosts the application and data centrally—deploying patches and upgrades to the application transparently, and delivering access to end users over the Internet through a browser or smart-client application. Many vendors provide application programming interfaces (API) that expose the applications data and functionality to developers for use in creating composite applications. A variety of security mechanisms can be used to keep sensitive data safe in transmission and storage. Applications providers might provide tools that allow customers to modify the data schema, workflow, and other aspects of the application’s operation for their use. – Software as a Service (SaaS): An Enterprise Perspective
- Usage. Rates vary based on the actual usage of the application.
- Flat Rate. Pay a one-time flat rate or annual rate for unlimited access.
- Subscription. Pay an ongoing monthly (or annual) fee for use of the application.
Examples: Salesforce.com, Microsoft BPOS, Google Apps
Benefits are the same as the benefits identified in the Cloud Value Proposition.
Additional Considerations: Management, Integration, Security, Disaster Recovery, Data Location and Security, Migration
- Network-based access to, and management of, commercially available software
- Activities managed from central locations rather than at each customer’s site, enabling customers to access applications remotely via the Web
- Application delivery in a one-to-many model (single instance, multi-tenant architecture), including architecture, pricing, partnering, and management characteristics
- Centralized feature updating to download patches and upgrades.
- Integration into a larger network of communicating software – either as part of a mashup or as a plugin to a platform as a service.