If you are planning on moving to the Cloud, you need to make decisions about exactly which of your applications you will be moving. The National Institute of Standards and Technology (NIST) has developed a Definition of Cloud Computing that outlines the currently available application options: Software as a Service (SaaS), Platform as a Service (PaaS), and Infrastructure as a Service (IaaS) – I gave a brief overview of each of these in a post from last June.
Keep in mind that you don’t need to commit all your resources to one type of Cloud application – you can pick and choose resources according to your needs. For example, moving your website to a PaaS vendor, while using Exchange on IaaS for your mail, and a SaaS CRM application.
Before you make any decisions on which model of cloud you would like to use, first examine the applications you’re currently using – are they performing satisfactorily? Are there any problems with the applications? Do you anticipate problems with them in the future? If you anticipate sales growth, will your CRM be able to keep up with the new customers? If you’re rolling out a new web application, will your web servers be able to handle the extra load?
If an application you’re using is performing well, and you anticipate that it will continue to perform well, but may need more resources, then using IaaS can help you by providing extra resources based on, and priced by, demand. IaaS also has the benefit of allowing you to use the same server platform you’re currently using, making it easier to move applications to and from the cloud. The one drawback IaaS has as compared to other cloud technologies is that, as with any virtual server, you still have to install and administer the OS and applications, and may well need to provide licensing for both.
However, if you have applications that need to be replaced, SaaS applications have the advantage of offloading application development, maintenance and support to the vendor, and vendors may also provide training materials to get your organization up to speed quickly.
There are downsides to SaaS. Applications may not be as customizable as you would like. And, if you want to move to a different application, you need to export the information you’ve configured for your company, and then import it to another application.
PaaS addresses the customization problems found in SaaS – since you develop the application, it can be customized as much as needed. Depending on the platform used to develop the application, it may be very easy to transfer the application to a new PaaS vendor. The drawbacks to PaaS include needing to allocate resources to application development, and having to provide training for the applications.
Another factor to consider when determining which Application model meets your needs is how that model is deployed. In Part 3, we’ll look at the different Cloud deployment models, and what you need to consider when choosing where your cloud is deployed.