Despite the continuing spread of the cloud and the software-as-a-service (SaaS) model, you always meet again and again people, who are anchored in the firm belief to offer cloud computing since 20 years. Because ASP (Application Service Providing) was finally nothing else. The situation is similar with traditional outsourcers, whose pre-sales team will gladly agreed for an appointment after a call to model the customers ‚tailored‘ cloud computing server infrastructure locally, which may be paid by the customer in advance. In this post it’s only about why ASP has nothing to do with SaaS and cloud.
ASP: 50 customers and 50 applications
Let’s be honest. A company that wants to distribute an application will come sooner or later to the idea that it somehow wants to maximize its profits. In this context, economies of scale have an important role to place an efficient solution on the market that is designed that it remains profitable in spite of its own growth. Unfortunately, an ASP model can not prove exactly that. Because ASP has one problem. It does not scale dynamically. But is only as fast as the administrator must ensure that another server is purchased, installed in the server room, equipped with the operating system and other basic software plus the actual client software.
Furthermore, in the typical ASP model, for each customer an instance of the respective software is needed. In the worst case (depending on performance) at least even a separate (physical) server for each customer is required. This means in numbers, that for 50 customers who want to use exactly the same application but separated from each other, 50 installations of the application and 50 servers are required. Topics such as databases should not be forgotten, where in many cases, up to three times as many databases must be used as applications are provided to customers.
Just consider yourself the effort (cost) that an ASP provider operates to integrate and manage the hosted systems, to service new customers and beyond that to provide them with patches and upgrades. This is unprofitable!
SaaS: 50 customers and 1 application
Compared to ASP SaaS sets on a much more efficient and more profitable model. Instead of running one application for each customer, only one instance of an application for all customers is used. This means that for 50 customers only one instance of the application is required, that all together are using but isolated from each other. Thus, the expenses for the operation and management of the application is reduced in particular. Where an administrator at the ASP model had to update each of the 50 software installation, it is sufficient for SaaS, if a single instance is updated. If new customers want to take advantage to access the application, it is automatically set up, without an administrator needs to install a new server and set up the application for them. This saves both time and capital. This means that the application grows profitable with the requirements of new customers.
Multi-tenancy is the key to success
The concept behind SaaS, which accounts for a significant difference between ASP and SaaS, is called multi-tenancy. Here are several mandates, ie customers, hosted on the same server or software system, without beeing able to look in the data, settings, etc. of each other. This means that only a customer can see and edit its data. A single mandate within the system forms a related to the data and organizationally closed unity.
As noted above, the benefits of a multitenancy system is to centrally install the application, to maintain and optimize memory requirements for data storage. This is due to the fact that data and objects are held across clients and just need to be stored for an installed system and not per mandate. In this context, it must be stressed again that a software system is not multitenant by giving each client its own instance of software. Within the multi-tenancy method all clients using one instance of an application that is centrally managed.
If you still have the question why not to sell ASP as SaaS, read „Software-as-a-Service: Why your application belongs to the cloud as well„.