IaaS (Infrastructure as a Service)
IaaS is a cloud computing model that provides virtualized computing resources - such as servers, storage, and networking - over the internet.
What is IaaS?
Infrastructure as a Service (IaaS) is a cloud service model where providers deliver on-demand infrastructure resources, including virtual machines, storage, networks, and load balancers. Organizations manage the operating systems, applications, and configurations, while the provider manages the physical hardware and virtualization layer.
Why IaaS matters
IaaS is important because it:
- Eliminates the need to purchase and maintain physical servers
- Enables rapid provisioning and scalability
- Provides flexibility and control over system configuration
- Supports hybrid and multi-cloud architectures
- Serves as the foundation for many cloud workloads
IaaS is often the first step in cloud adoption.
What IaaS typically includes
IaaS offerings commonly provide:
- Virtual machines and bare-metal instances
- Virtual networking (VPCs, subnets, routing)
- Block, file, and object storage
- Load balancers and firewalls
- Basic monitoring and availability services
The infrastructure is delivered via self-service portals and APIs.
IaaS vs PaaS vs SaaS
| Model | You manage | Provider manages |
|---|---|---|
| IaaS | OS, runtime, apps | Hardware, virtualization |
| PaaS | Application code | Infrastructure, OS, runtime |
| SaaS | Configuration & data | Entire stack |
IaaS offers the most control and the most responsibility.
IaaS and virtualization
IaaS relies heavily on:
- Hypervisors for workload isolation
- Virtual networks for segmentation
- Software-defined storage
Virtualization enables elastic scaling and multi-tenant infrastructure.
IaaS and security responsibilities
Under the shared responsibility model:
- Providers secure physical data centers and hardware
- Customers secure operating systems, applications, identities, and data
Misconfigurations at the OS or network level are a common risk.
IaaS use cases
IaaS is commonly used for:
- Hosting legacy applications
- Disaster recovery and backup
- Development and testing environments
- High-performance or specialized workloads
- Private cloud and hybrid scenarios
Benefits and trade-offs
Benefits
- High flexibility and customization
- Pay-as-you-go pricing
- Rapid scaling and global reach
Trade-offs
- Higher operational complexity
- Greater security responsibility
- Cost management challenges
- Requires skilled IT operations
Common misconceptions
- "IaaS is just another name for virtualization"
- "IaaS is always cheaper than on-premises"
- "Cloud providers handle all security"
- "IaaS removes the need for system administration"