Learn in the textbookCloud Service Models (○aaS)
DefinitionIaaS (Infrastructure as a Service) is a model in which a provider offers, over the network, hardware resources (ハードウェア資源) such as server processing power, storage and network lines.
ExplanationUsers choose and rent the number of machines and the capacity they need, then install and manage the software from the OS up on their own. They are free to decide the configuration, but in exchange more of the operating work stays on their side.
AnalogyIt is like renting a building where only the frame and walls are finished, and fitting out the interior and furniture yourself.
Memory hookI stands for Infrastructure, the things like roads and water mains that hold everything up from below. It points to the bottom layer of the service models.