SaaS (born software as a service - software as a service, as the English. Software on demand - software on demand) - a business model of selling and use the software, in which the supplier is developing a web-based application and manages them by providing the customer access to the software via the Internet. The main advantage of the SaaS model for the customer services is the absence of costs associated with the installation, upgrade, and support of the equipment and operating software on it.
In the model of SaaS:
app adapted for remote use;
one application is used by several clients (application utilities);
payment is either a monthly fee or based on the volume of transactions;
Technical support is included in the application fee;
modernization and renewal applications are promptly and transparently to clients.
Under the SaaS model, customers pay not for owning the software itself but for its lease (that is, its use through a web interface). Thus, in contrast to the classical software licensing scheme, the customer is relatively low recurrent costs, and does not need to invest heavily in the acquisition of software and hardware platform for deploying and then maintain its performance. Periodic payment scheme implies that, if the need for the software is not available, the customer can stop using it and freeze pay the developer.
From the point of view of the developer of a proprietary software SaaS model can effectively deal with unlicensed use of software, because the software itself does not get to the end users. In addition, the concept of SaaS can often reduce the cost of deployment and implementation of technical and advisory support of the product, although it does not eliminate them entirely.