Just had an interesting discussion with a senior executive and the topic was what is the difference between PaaS (platform-as-a-service), SaaS (software-as-a-service), and IaaS (infrastructure-as-a-service)?
The very foundation of a "cloud" computing environment centers on these core elements. An effective understanding of them is necessary to compare the options and leverage the cost benefits of the "cloud." By now I believe that the users at large are familiar with and understand what SaaS means but to simply define it; SaaS represents any software tool that is available over the web, utilizing a browser to access, manage, utilize and deploy to the end-user, any application absent the necessity to install such software on their own server platform.
Now to better understand the other two, PaaS and IaaS, we need to first build out three basic concepts; the end-user, the middleware and the core system when one looks at the entire IT system. To build any IT system you first address the core systems-the physical hardware. This can be installed in a closet, a server room or in some data center offsite. It is the offsite installation that brings us to the "cloud". Next you have the middleware- software that runs the hardware on the backend, the operating system, the plug and play software at the heart of every application and lastly the user interface to actually access and use a given piece of software.
The core system and the middleware represent the platform-as-a-service. The large cloud providers will all supply a company with a platform from which to install and run their own IT environment. They essentially provide the hardware, the OS software, the power, connectivity and secure environment for all of the equipment. They rent you the platform based on memory storage, CPU capacity and access bandwidth. From there you install your application software packages; you provide the IT systems admin, the network admin, the programming support for all applications and the licensing to run all systems.
Going a step further, we realize the infrastructure-as-a-service. In the final element the cloud allows us the ability to deliver not only the platform-as-a-service but we can also deliver the software, the licenses, and all levels of system support allowing the company to significantly reduce in-house IT staff from their overhead cost structure. The companies will then realize the economies of scale that a cloud provider can deliver by leveraging their resources in a unique environment or in a multi-tenant environment where the computing resources are shared across many companies and the smart-hands of the skilled administrators and programmers are at their disposal but not on their payroll.
Where does VCO Desk fit into all of this? In VCO Desk the platform is delivered via a secure connection using Citrix. Once you have logged into the system your VCO desktop opens and in it you now have specific software applications available to use. This infrastructure is the supported software (middleware) that the user needs to do their work. These applications are associated with the core operating system, such as XP or Windows 7, and the other basic MS Office applications like Word, Excel, PowerPoint and so forth. Then come the other supported tools like Acrobat, as well as user-specific SaaS applications unique to their own environment. There are other elements that can be layered into VCO Desk such as telephony, document management and direct support server applications provided by the user's company, yet deployed on the Acris Technology cloud server set. All of these IT elements are managed and offered to the user, accessible from any location on any device, via a simple Internet connection to the Acris Technology "cloud."