The most simple definition of cloud computing means storing and accessing data and programs over the Internet instead of on a local computer's hard drive or on a server inside your company’s firewall.
Not all clouds are created equal, however. Today there are three primary models for cloud computing in business:
Infrastructure as a Service (IaaS)
Infrastructure as a Service provides the basic building blocks for IT such as servers, databases and data storage. Infrastructure as a Service is most similar to traditional on-premise IT departments who are used to managing individual servers, databases and networking tools but these components will reside within the cloud provider's data centers rather than locally within a company’s own premises. While providing some efficiencies and cost savings through use of the cloud provider’s data centers, IaaS has little or no impact on application functionality or capability as the underlying technologies, while running in a different location, are fundamentally the same.
Platform as a Service (PaaS)
Platforms as a service also remove the need for organizations to manage the underlying technical components such as servers and operating systems but also allows a business to focus on the deployment and management of business applications running on a shared technical backbone or platform. With a platform, businesses can run applications developed by multiple 3rd parties alongside applications they build themselves. These apps use common services and capabilities such as single security model, reporting, analytics, mobile and social collaboration tools. End users of platform applications benefit from ease of use and familiarity of user interface. Businesses benefit because of increased speed of development and rollout of new capabilities often through simple point and click configuration rather than requiring developers to write and maintain code. Businesses can also gain better business insight when data from all their applications resides in a shared single common database.
Software as a Service (SaaS)
Software as a Service provides end user applications that are built, run and managed by a 3rd party service provider, however the focus is purely on the end user apps and the underlying technologies are not exposed to the user of those applications. SaaS does not require end users to maintain or access the underlying technical services used by that application, but the danger of using multiple applications running on different underlying technical architectures is that integration can quickly become complex, data needs to be replicated and synchronized and it becomes harder to get a complete view across the entire business. The proliferation of SaaS apps on multiple architectures within a single company have been described as a “FrankenCloud."
For more information on how FinancialForce applications, delivered using the Salesforce platform as a Service, help you avoid your own FrankenCloud, download the FrankenCloud white paper.