When Tom Sawyer talked his buddies in to white-washing Aunt Polly’s fence he didn’t call it outsourcing. But he could have.
To “outsource” is to go “outside” (in Tom’s case, outside of the household) and find a solution. The latest buzzword for outsourcing is “cloud computing.”
Cloud computing has lots of definitions but I like to start at virtualization. To virtualize is to remove the hardware requirement from a resource. A virtual network (VLAN) is the ability to create separate logical networks on the same hardware, virtual machines (VMs) are multiple logical computers on one physical server. The “cloud” provides you a resource and hides everything but the resource. “Cloud” doesn’t require virtualization itself, but does hide the underlying components from the provided resource.
Ok, so what is a resource?
A computer requires physical space, hardware, storage, networking, OS, and the application layer (database, client access, processing, reporting). A Cloud will provide one or all of these resources except physical space (hey it’s a cloud!).
Like Tom and Huck (or, maybe Huck and Jim?) one good buzzword needs another. Cloud proponents like to tack on to each resource the cloud can provide with “?-as-a-Service” and then abbreviate it “?aaS”
Thus we have :
Storage-as-a-service – provides storage only
Network-as-a-service – provides networking only
Infrastructure-as-a-Service – provides with hardware, you add the OS and applications
Platform-as-a-Service – provides an Operating System, you add the applications
Software-as-a-Service – provides the complete experience for the end-user (quickbooks online, etc)
Communications-as-a-Service – typically outside of the server/app model this usually means the phone/ IM / FAX / carrier pigeons / African swallows are being provided.
As you move down the line you outsource more and more of your IT needs to the cloud provider.
