Infrastructure as a Service IaaS

What is IaaS (Infrastructure as a Service)?

IaaS, short for "Infrastructure as a Service," is a cloud computing service that provides virtualized resources such as servers, storage, and networking equipment over the internet for building and managing IT systems. Initially referred to as HaaS (Hardware as a Service) to highlight its role as a service for hardware, the term evolved to IaaS to distinguish it from related services like PaaS (Platform as a Service) and SaaS (Software as a Service) and to reflect its broader scope.

The differences between IaaS, PaaS, and SaaS can be summarized as follows:

• IaaS:
  IaaS provides virtualized servers, storage, firewalls, and networking (usually VLANs) in the cloud. Customers are responsible for installing and managing the operating system required to run applications. A representative example of IaaS is Amazon Elastic Compute Cloud (EC2).
• PaaS:
  PaaS offers a platform in the cloud for application development and deployment. It includes pre-installed operating systems, development environments, databases, and middleware (e.g., web servers). Infrastructure management is handled by the service provider. A notable example is Microsoft Azure.
• SaaS:
  SaaS delivers specific applications hosted in the cloud. Users access these applications without managing underlying infrastructure. An example is Google Apps, provided by Google.

IaaS resembles hosting services but differs in some key aspects:

1. Pay-as-you-go model: Unlike hosting services, which often charge a fixed monthly fee per server, IaaS uses a consumption-based pricing structure.
2. Customizable server specifications: IaaS offers greater flexibility in server configurations compared to hosting.
3. On-demand provisioning: Servers can be deployed quickly via self-service portals, reducing setup times.