Infrastructure-as-a-service (IaaS) is an on-demand, online, and pay-as-you-go delivery of scalable computing resources, including hardware, storage, virtualization, network, security, operating system, and software applications designed to replace a traditional data center.
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The IaaS model
Sun Microsystems identifies Infrastructure as a Service as one of three layers of cloud computing, in addition to Software as a Service (SaaS) and Platform as a Service (PaaS).
Keeping a cloud infrastructure requires a team of engineers and programmers on top of its high acquisition and maintenance costs. Such a steep capital outlay is prohibitive to small and medium businesses. Thus, there is rising demand for Infrastructure-as-a-Service, as it allows companies to scale processes based on requirements and workloads without necessarily owning the infrastructure. With the IaaS model, software and servers are purchased as a fully outsourced service and billed on usage and how much of the resource is used – compared to the traditional method of buying software and servers outright.
How does IaaS work?
IaaS consists of hardware and software resources for running computer applications and different types of end-user workloads in the cloud.
The provider owns and manages the entire cloud infrastructure—virtual machines, servers, routers, load balancers, firewalls, switches, disks for memory storage, and other facilities in the data center. End users are charged based on either a consumption or per-use model for access to the resources over the internet instead of acquiring the whole thing.
How is IaaS different from SaaS and PaaS?
Sun Microsystems identifies Infrastructure as a Service (IaaS) as one of three layers of cloud computing, in addition to Software as a Service (SaaS) and Platform as a Service (PaaS).
While IaaS delivers networking, virtualization, and cloud storage to customers, PaaS offers hardware and software tools for applications development. SaaS, which can be integrated with IaaS, provides software applications built on IaaS or PaaS platforms that are ready for use by customers or end users.
Read more on the differences between the three layers of cloud computing from TechRepublic.
IaaS use cases
Customers, usually businesses, take advantage of IaaS for various uses and different types of workloads:
- Software development, including testing and deployment
- Website hosting
- Web applications management and support
- Server resource
- Content delivery
- High-performance computing
- Data warehousing and analytics
- Ultra-large data storage for backup and recovery
What are the advantages of IaaS?
Choosing IaaS offers businesses with financial and efficiency benefits, including:
- Cost-Efficiency: Reduces up-front capital expenditure since users only pay the services based on consumption. Having no team of computer experts to maintain the otherwise expensive infrastructure, the business can allocate its resources to other profitable ventures.
- Scalability: Provides flexibility as usage depends on the amount and type of workloads. Users can scale up or scale down to fit the demands and data requirements.
- Security: Delivers data privacy and security maintained by teams of top security experts. Security, which is fundamental to data storage, is part of every IaaS offering. In cases of data loss due to disasters or theft, multiple locations make recovery possible and easy.
- Increased Productivity: Allows businesses to accelerate their work and enhance growth due to reduced downtime and high-performance computing.
- Customizabiity: Offers customers solutions based on their specific needs.
Some examples of IaaS
Infrastructure-as-a-Service can be deployed through a private, public, or hybrid cloud. And the market is dominated by the big names in the cloud service industry, like Amazon Web Services (AWS), Microsoft Azure, Google Cloud, IBM Smart Cloud, and Oracle Cloud.