1 My second bachelor thesis is about Software as a Service Communication and Collaboration Applications. I compared Google Apps and Microsoft Office 365, but although showed off advantages and disadvantages, risks and which factors have to be taken in consideration if a migration is imminent.
2 At first I want to point out the common architecture of SaaS services. As you can see, the ideal way to distribute the software is the web - using web 2.0 technologies. The hardware and interfaces used by the services are defined by scalable layers to compute and store data and are normally made available by further providers. That is called Utility Computing.
The whole infrastructure uses a multi-tenant architecture. All the customers are using an instance of the same program base. According to the architecture it adds another service layer to control the resources, features and the configuration of several end customers.
3 To define the usage of business applications, it can be generally broken apart into these two arguments. We can mirror whole business processes, like customer relationship management, entity relationship management, human resources management, communication systems or collaboration systems. Principally we just edit, store, share or control data.
4 During my research I read about many advantages of Software as a Service. The most heard fact is that it has minor costs, especially at the beginning or during the migration. That may be true if we don’t include the Total Cost of Ownership that I will mention later.
Reliability is implied by the fact that the customers use the same program base and only different instances of it. If problems occur they are faster detected and can be solved on-the-fly and for free through the general support.
Because the providers need to stay competitive, their software gets further improved by their developers. They almost use the newest technologies and add new features, so the software used is always up-to-date.
The performance is a result of the architecture of SaaS software. The underlying utility computing services are fully scalable.
The costs, at least of the software and support itself, are known. We have user-based, feature-based or time-based pricing models.
The risks are decreased because of the on-demand or leasing model, businesses don’t have to think about maintenance and performance the software because of the SLA and are fully concentrated on the core business tasks.
5 Somebody would think now: Why not SaaS everything up? But in practical there are some barriers to take. I will now list some of the greatest problems of SaaS that I encountered.
6 Most contracts are not dimensioned for business-critical processes. On the slide we can see the SLA of Google Apps. Actually Google convinces its future customers with an availability of 100%, but the contract doesn’t comply.
The greatest fail concerning this matter was the breakdown of Amazons EZ2 in 2009, which is one of the biggest utility computin