Overview#Infrastructure as a Service (IaaS) is a Cloud Services Model which provides self-service models for assessing, monitoring, and managing remote datacenter infrastructures, such as compute (virtualized or bare metal), storage, networking, and networking services (e.g. firewalls).
With Infrastructure as a Service instead of having to purchase hardware outright, users can purchase Infrastructure as a Service based on consumption, similar to electricity or other utility billing.
Providers still manage virtualization, servers, hard drives, storage, and networking.
Many Infrastructure as a Service providers now offer databases, messaging queues, and other services above the virtualization layer as well. Some tech analysts draw a distinction here and use the Infrastructure as a Service moniker for these other options. What users gain with IaaS is infrastructure on top of which they can install any required platform. Users are responsible for updating these if new versions are released.