Infrastructure as a Service (IaaS)
What Is Infrastructure as a Service?
Infrastructure as a Service (IaaS) is a cloud computing delivery model in which a cloud provider supplies virtualized computing resources, including servers, storage, networking, and virtualization, over the internet on a pay-as-you-use basis. Organizations provision and manage the operating systems, middleware, applications, and data within this rented infrastructure, while the provider manages the underlying physical hardware and its maintenance.
IaaS gives organizations the flexibility and scalability of cloud infrastructure without the capital expenditure and operational complexity of owning and maintaining physical data centre equipment.
The Cloud Service Model Hierarchy
IaaS provides the raw infrastructure layer: compute, storage, and networking. The customer controls everything above the hypervisor.
PaaS (Platform as a Service) adds a managed runtime environment, middleware, and development tools on top of the infrastructure. The provider manages the OS and infrastructure; the customer manages applications and data.
SaaS (Software as a Service) delivers fully managed applications over the internet. The provider manages everything; the customer uses the software through a browser or client.
Leading IaaS Providers and Their Offerings
Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP) are the dominant IaaS providers globally. Each offers a broad catalogue of compute instances, storage services, managed databases, networking components, and adjacent platform services. Organizations frequently adopt a multi-cloud or hybrid strategy, using different providers for specific workloads based on pricing, capability, geographic availability, or existing commitments.
IaaS Use Cases in Enterprise Environments
- Hosting web applications and e-commerce platforms without maintaining physical servers
- Development and test environments provisioned on demand and decommissioned when no longer needed
- Disaster recovery: maintaining standby infrastructure in a cloud region for rapid failover
- Big data analytics: spinning up large compute clusters for processing workloads and releasing them when complete
- Backup and archive: low-cost object storage for long-term data retention
Key Takeaways
- IaaS delivers virtualized compute, storage, and networking resources on a pay-as-you-go basis through cloud providers.
- The customer manages the OS, middleware, and applications; the provider manages the physical infrastructure.
- AWS, Azure, and GCP are the leading IaaS providers, each offering broad service catalogs across global regions.
- IaaS eliminates physical data center capex and enables elastic scaling of infrastructure based on demand.
- Common use cases include application hosting, DR environments, development infrastructure, analytics workloads, and cloud backup.