Software as a service (SaaS, On-Demand Software)
NIST defines SaaS cloud computing as:
“The consumer can use the provider’s applications on a cloud infrastructure. The applications are accessible from various client devices through either a thin client interface, such as a web browser (e.g., web-based email), or a program interface. 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.”
SaaS vendors offer online services that provide structured application software and databases and price their solution on a subscription or pay-per-use basis.
Users access SaaS applications across the internet, usually using a web browser. Meanwhile, the SaaS vendor manages infrastructure and platforms that run the applications, simplifying maintenance and support.
SaaS applications differ from on-premise solutions in that they are designed to scale at run-time to meet changing work demands.
Transparent to the user, this is accomplished by using load balancers to distribute the work over the set of virtual machines.
These applications are designed in this fashion to accommodate many users or data. Additionally, SaaS solutions are almost always multi-tenant solutions, serving more than one organization simultaneously.Back to Glossary