For several days I was thinking to write a post about the differences between ASP and Saas and yesterday I decided to do because of an email I received from one of the readers of this humble blog. In the mail, there was a series of questions using the acronym asp and other using the acronym SaaS, and I was unable to identify whether it was a matter of right or use of the acronym that were really confusing.

If you seek information from the term ASP and Saas and even if “differences between ASP and Saas” many entries appear that attempt to explain the terms but most of the comparisons confuse the term ASP hosting and from there the comparison does not fit with Saas. I would like to clarify first “what is ASP and What is Hosting?” based on these definitions:

ASP is a paid platform. Within its single fee it include licensing, dedicated hosting, maintenance, etc.

In regime, Hosting pay licenses and / or project and servers can host it on your property or perhaps the provider.

I think it is clear that pay-per-use ASP Hosting and pay licenses to use products and machines can be yours or rented but are in provider’s premises. Clarifying these concepts, I will try to clarify the differences between ASP and SaaS.

ASP stands for Application Service Provider and the Wikipedia explains in its first paragraph that it provides software services.

Among the factors that characterize a PSA highlights the widespread use of Internet , the ability to accelerate the deployment and implementation of applications and portability of services and operations to third parties. The main barrier to a PSA lies in convincing their customers that their information with a third remains secure. On the other hand, own and operate the software and hardware environment and rented to customers to use computer applications.

Let us now turn to the definition that makes SaaS wiki:

“Software as a Service (SaaS) is a distribution model of software where the IT company provides maintenance, daily operations, and support software used by the client. In other words, it is to have the information, processing, inputs and outcomes of the business logic of the software. In simple words: The customer has the system hosted in the IT company. It is software accessed via Internet . It is not necessarily to operate through Web browsers, business logic resides in the central city of provider.

And the truth is written in different words but there are very few differences:

• Accessed via the Internet.
• In a service operation and maintenance.
• You pay per use, not license.
• The data and business logic in provider’s premises.

Applications will not necessarily be delivered through web browsers and therefore at times be necessary to install software on the client and not others.

And then ” What are the differences between ASP and SaaS?”. For a though, it does not seem if there are differences:

ASP is a proprietary software from other ISVs . In the SaaS model there are those ISVs (software developers) that offer hosting and software in one package.

Many of the applications running in the ASP are not prepared to provide access via the Internet. I’ve seen agreements of HP, SAP, etc. with ASP to offer internet through the same applications that were designed to run in-house.

These same applications were not designed to serve multiple clients from different companies, moreover, is running an instance for each client of the ASP. Most applications as a service (SaaS) are designed to deliver the application to multiple clients through a single instance (multitenancy).

Relating to the above, to provide coverage instance to several clients at once it is necessary that the application has a high level customization for each client.

Although we have seen that not necessarily the applications offered as a service (SaaS) are consumed through a browser and therefore do not require installation on the client, in fact most of them are consumed by the browser. In fact I know that Saas is not the case. The applications running on ASP may or may not run through the browser and therefore require additional installation on the client (a Windows emulator or unix, remote desktop, terminal server , citrix).

Related to the above, ASP can offer different applications and different types depending on the agreements reached with the companies that own software. This however is more complicated to get into the SaaS model, normally ISV offers a single software but we also have example like google apps.

Finally, something more than evident is that SaaS can enjoy direct support, more personalized, and without intermediaries who can pass the buck to a software problem.

I hope the post has been cleared to add more questions and that in any case in controversy, sufficient to get us to clarify the terms.