Cloud application services, or Software as a Service (SaaS), represent the largest cloud market and are still growing quickly. SaaS uses the web to deliver applications that are managed by a third-party vendor and whose interface is accessed on the clients’ side. Most SaaS applications can be run directly from a web browser without any downloads or installations required, although some require plugins.
Because of the web delivery model, SaaS eliminates the need to install and run applications on individual computers. With SaaS, it’s easy for enterprises to streamline their maintenance and support, because everything can be managed by vendors: applications, runtime, data, middleware, OSes, virtualization, servers, storage and networking.
There are a few major characteristics that apply to most SaaS vendors:
- Updates are applied automatically without customer intervention
- The service is purchased on a subscription basis
- No hardware is required to be installed by the customer
SaaS is also known as hosted software or on-demand software.
SaaS is a natural evolution of software. The old model of getting physical DVDs and installing on local servers was the only realistic solution for many years. In fact, the client-server model is still required for many scenarios. That said, in recent years a number of developments have allowed SaaS to become mainstream. One factor is bandwidth; the internet is simply faster than it was a decade ago. Other major factors include the evolution of both virtualization and tools in big data. All these advances have made it much easier for providers to scale and manage their own infrastructure and thus provide SaaS solutions.
SaaS is used in a number of common business areas, including customer relationship management (CRM), document management, accounting, human resource (HR) management, service desk management, content management and collaboration. There are literally thousands of SaaS vendors, but Salesforce.com is perhaps the best known example, as it is one of the first vendors to significantly disrupt a traditional software vertical.
SaaS is closely related to platform as a service (PaaS) and infrastructure as a service (IaaS). It falls under the umbrella of the larger category of cloud computing, although many people view the terms as synonymous.
Popular SaaS offering types include email and collaboration, customer relationship management, and healthcare-related applications. Some large enterprises that are not traditionally thought of as software vendors have started building SaaS as an additional source of revenue in order to gain a competitive advantage.
SaaS Examples: Google Apps, Salesforce, Workday, Concur, Citrix GoToMeeting, Cisco WebEx
Common SaaS Use-Case: Replaces traditional on-device software