What is IaaS (Infrastructure as a Service) and How Does It Work?

Infrastructure as a Service, or  IaaS, is one of the main three fundamental service delivery methods for cloud computing, alongside Platform as a Service and Software as a Service.

It allows you to access compute, storage, networking, servers and virtualisation via the internet from a third-party provider in order to create the IT environment that best fits your business requirements. It is also one of the fastest-growing categories of cloud computing because of the growing number of enterprises that are using IaaS to make the shift from being solely on premise.

IaaS refers to the pool of physical or virtual infrastructure that a cloud provider will deliver for an organisation from its data centres. The components that IaaS provides to a customer include the data centres, the servers, storage, networking as well as the virtualisation or hypervisor layer if required. The customer just decides how much resource it requires and orders it accordingly.

Typically IaaS will also include the management of the infrastructure but can also include other services such as IP address, network connections, load balancers, billing management, access management as well as storage resiliency, backup and replication. These resources allow the users to install operating systems, deploy databases, create storage and install workloads as they require.

IaaS tends to be charged on a pay-as-you-go hourly, weekly or monthly basis. The availability of the service and the details of the way the infrastructure is configured can is very much dependent on the IaaS provider.

IaaS, PaaS and SaaS: What’s the Difference?

Platform as a Service (PaaS) is the next step up from IaaS, where the provider also supplies the operating environment including the operating system, application services, middleware and other ‘runtimes’ for cloud users. It’s used for development environments where the business can focus on creating an app but wants someone else to maintain the deployment platform. It means you have much simpler workloads but you can’t necessarily be as flexible as you want.

At the highest level of orchestration is Software as a Service (SaaS) where applications are accessed on demand. Here you just open your browser and go, consuming software rather than installing and running it. A user simply logs on to access the provider’s application. Users can decide how the app will work but pretty much everything else is the responsibility of the software provider.

Benefits of IaaS

So why would you choose IaaS? IaaS allows you to significantly reduce the cost of your IT infrastructure because there is no need for you to purchase your own data centre hardware or monitor and maintain your own equipment. You hand responsibility for the maintenance of the infrastructure to the IaaS provider whose job it is to ensure its availability.

The main benefits of IaaS are:

  • Cost effective
  • Pay-as-you-go OPEX model
  • High degree of control over resources
  • Scalable capacity to meet changing demand
  • Access services as you need them and from anywhere
  • Secure data centres
  • Redundant and resilient – no single point of failure
  • 24/7/365 availability
  • Develop and get services to market quickly

The drawback to IaaS centres on your ability to manage it. If there are issues with the network or downtime, workloads will be affected so it can be more difficult to manage and monitor. It is therefore essential to have staff who understand it and can manage the relationship with the IaaS provider.

Example Cases for IaaS

There are a many different circumstances in which you would use IaaS. It is particularly useful for creating and testing new workloads. If an organisation is creating a new application it might be cheaper to host and test it with an IaaS provider. Once it’s been tested successfully the workload can then be brought in house or kept on a long-term deployment.

By using IaaS a business can use a third party to host and scale their IT systems as they grow. They can host websites on pooled virtual resources from their provider’s physical servers or create a virtualised network of interconnected servers.

Drivers for choosing IaaS include:

  • Test and development
  • Website hosting
  • Storage, backup and recovery
  • Web application hosting
  • High performance computing
  • Big Data

IaaS Providers

The major IaaS providers are AWS, Microsoft Azure and Google Cloud. However there are other suppliers, such as iomart, that offer all the benefits of IaaS from these hyper vendors along with additional options that are more dedicated to a single tenant who wants the security of knowing that they are being hosted in UK data centres. All offer a broad range of services to support the most complicated of hosting environments.

iomart offers a variety of IaaS solutions which cover the differing requirements of the modern business:

Public Cloud – the multi-tenant option via iomart’s own public cloud or the managed clouds of AWS, Microsoft Azure and Google Cloud.

Private Cloud – a secure single tenant solution for more sensitive data.

Hybrid Cloud – a combination of public and private cloud for scalable, high performance infrastructure.

Dedicated Servers (Bare metal) – the option for single tenants with business-critical operations who have strict regulatory compliance.