But, SaaS is used interchangeably and sometimes used to replace the definition of "Application Services Providers" (ASP). Many of you may know about ASPs and ISPs (Internet Service Providers). SalesForce is a good example of ASP. ASPs deliver application functionality (rather than software) as an outsourced service and charge on usage basis. ISPs provide internet service as an outsourced service. AOL is a good example of ISPs. For lack of better term we can call service providers who delivers software as a service as "Software Service Providers" (SSP).
Unlike the existing definitions and differentiations between SaaS and ASPs, I think there is an important distinction between ASP and SaaS. In case of ASPs, the software is not shipped to the customers; the customers access the "required functionality" and use the functionality via a remote client i.e. the software execution happens in the ASPs' end while the customers access the application. In case of SSPs, the software is shipped to (or downloaded by) the customers, deployed within customers' premises (or their co-location) and gets executed within the customers’ environment. Anti Virus Software is a good example for SSPs, where subscriptions are charged for virus definition updates and not for the anti virus software itself. Moreover in ASP model when a service is stopped, the customer has to migrate their data to a different environment, where as in SSP model the customer can still run the software (along with their data) without any associated value-added services (like future updates).
Here are 5 things you want to adopt if you want to be a SaaS provider:
Murugan Pal is the founder and CTO of SpikeSource, Inc.
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