Core Blog

Three categories of cloud computing explained: IaaS, PaaS and SaaS

Written by Lucy Wright | Nov 23, 2020 9:40:58 AM

Almost every business today runs at least one application in the cloud, and growing numbers of CEOs report having a cloud-first IT strategy. In fact, the stats in our infographic from earlier this year show that the cloud is now normal. And the events of 2020 have meant that even those organisations still lagging behind in their cloud adoption have turned to cloud solutions to enable remote working and business as usual activity to continue during lockdown.

While the cloud has so many benefits for business it’s almost a no-brainer, it isn’t necessarily a “one size fits all” solution.

Different cloud services have different advantages and potential drawbacks, all of which need to be considered. Some organisations are happy to wash their hands of managing their own IT and invest in a full Infrastructure as a Service, such as Azure Active Directory, while others prefer to retain some control over their IT.

Here, we explain the three main types of cloud services and how they can benefit your business.

Infrastructure as a Service (IaaS)

Infrastructure as a Service (IaaS) is the foundation of cloud IT. IaaS is a computing infrastructure that is provisioned and managed over the internet (in the cloud) by a cloud service provider (CSP).

IaaS gives consumers great flexibility, because it can expand and contract with business needs. If business activity increases, for example, during busy retail periods, resources can be scaled up and back down again once activity returns to normal. And because physical hardware and servers aren’t needed with IaaS, organisations can save money on the initial expenditure and setup costs of an on-premise infrastructure, as well as on office space and maintaining the server.

A cloud service provider can also provide security as part of IaaS so that apps and data are protected at all times.

Platform as a Service (PaaS)

Platform as a Service (PaaS) gives organisations a development and deployment environment in the cloud which allows them to build and deliver simple to sophisticated cloud-based apps. PaaS is paid for on a pay-as-you-go basis as a subscription from a cloud service provider. It offers everything an organisation needs for the complete lifecycle of a web app, from building and testing to deploying, managing and updating.

PaaS contains the same infrastructure as IaaS but also includes development tools, database management and business intelligence (BI). The business manages the applications and services they develop, and the CSP manages the rest.

Software as a Service (SaaS)

Software as a Service, also known as SaaS, gives users access to cloud-based apps such as email and office tools, like those found in Microsoft’s enterprise-grade cloud, Microsoft 365.

SaaS is another pay-as-you-use service which automatically scales up and down according to the level of usage, so customers only pay for what they use. The service provider’s data centre holds all the infrastructure, middleware and app data, so SaaS customers don’t have to manage or maintain anything. A Service Level Agreement can be drawn up between the provider and the customer which outlines the minimum acceptable availability, downtime and resolution times if a problem occurs. SaaS lets business quickly deploy and use an app, with minimal initial expenditure.

SaaS allows users to access the apps from anywhere, on any device that’s connected to the internet, so it’s an integral part of enabling mobile working. Because data is stored in the cloud, if a user’s device is lost or damaged, data is still accessible.

Next steps

Wherever you are on your cloud journey, Core can help. We can plan for and migrate you to the Microsoft cloud, provide ongoing support once you’re using the cloud and offer Microsoft-funded workshops to help you get the most value from your licences once you’re using Microsoft 365. Talk to us about how we can help, or click here to view our workshops.