Infrastructure as a Service is a provision model in which an organization outsources the equipment used to support operations, including storage, hardware, servers and networking components. The service provider owns the equipment and is responsible for housing, running and maintaining it. The client typically pays on a per-use basis.

Characteristics and components of IaaS include:

• Utility computing service and billing model.
• Automation of administrative tasks.
• Dynamic scaling.
• Desktop virtualization.
• Policy-based services.
• Internet connectivity.

IaaS is one of three main categories of cloud computing service. The other two are Software as a Service (SaaS) and Platform as a Service (PaaS).

Infrastructure as a Service is sometimes referred to as Hardware as a Service (HaaS).