Cloud Services Explained: SaaS, PaaS and IaaS

By Matthew Reeve on 30th April, 2019.

All About the…As a Service?

Cloud solutions are for the most part no longer seen as an option, but a necessity. The versatility of cloud services has seen them impact everyone from small independent companies to global enterprises. But cloud services aren’t a one-size-fits-all solution, and with so many options and terminology relating to them, finding a suitable solution or service can be confusing.

Cloud Services Explained

We thought it would be helpful to decipher three of the most commonly used cloud service terms; Software as a Service (SaaS), Platform as a Service (PaaS) and Infrastructure as a Service (IaaS). All can be very beneficial to business but despite sounding very similar, their functions differ greatly, and their relevancy ultimately depends on the end users’ requirements. So, let’s break them down.

SaaS: Software as a Service

Definition: A method of software delivery in which software is accessed online via a subscription, rather than bought up-front and installed on individual devices.

Being the most commonly utilised of the three, you’ve likely heard of Software as a Service before and probably use SaaS delivered applications on a regular basis. Essentially, SaaS is remotely accessing cloud-based application services on demand, making them widespread throughout commercial markets using the cloud. As these applications are accessed through the internet, they often need no implementation by the end user. Well-known examples of SaaS applications are Uber, Netflix, Salesforce, Dropbox and Microsoft Office 365.

For businesses, Software as a Service applications provide a cost effective, flexible and simple solution in place of purchasing traditional software, which often came with a hefty up-front investment and installation period. Often multi-platform accessible (both web and mobile), SaaS can streamline business operations into one accessible resource, replacing many previously manual tasks, improving efficiencies and therefore saving time and money. With third parties hosting and maintaining the software, this also removes laborious installation and potentially costly technical support and maintenance costs. The SaaS model can also be scaled easily to meet the demands of the user and market.

PaaS: Platform as a Service

Definition: A cloud-based environment for application and resource design and development.

Similar to how the SaaS model allows users to access ready-to-use software, PaaS allows users to access platforms for software creation. Like SaaS, generally a third party provider will deliver the tools needed for development over the internet. These components provide a framework which the user can then use to build and tailor specific applications. The PaaS provider is usually responsible for hosting servers, storage, network and all other infrastructure. This allows the end user the freedom to focus on the build. Common examples of PaaS providers include Oracle Cloud, and Google’s App Engine.

As PaaS allows users to consume resources they don’t have to invest in or maintain, it can be extremely cost-effective. The PaaS providers environment will also be fully tested and optimised and in most cases, superior to anything the end user could construct themselves. As this model is delivered over the internet, the end user is not bound by location or time restraints, providing a quick and convenient solution. However, the biggest benefit of the PaaS model is the ability to provide a platform to quickly develop and customise applications to the end users’ requirements.

IaaS: Infrastructure as a Service

Definition: A cloud computing service where virtualised computing resources are outsourced and accessed via the internet.

Made possible through virtualisation, the IaaS model allows users to purchase and expand hosting infrastructure without having to make the investment into the actual hardware. The infrastructure isn’t owned by the user, but this also means they aren’t responsible for the maintenance and upkeep of it. Some examples of infrastructure that might be accessed as a service are servers, storage arrays, operating systems or networks. Although the hardware itself is physical on the providers end, the services they provide at the user’s end are virtual. An example of IaaS is Microsoft’s Azure cloud platform and Secura’s VPC.

The fact the service is completely virtual has huge appeal for businesses looking for an easily implemented, managed solution. The lack of responsibility for the managed services can be beneficial as it not only removes the investment needed to purchase the equipment but also the cost of maintaining and housing it.

The ‘as a Service’ Difference

Although each model may seem similar on the surface, as explained they provide very different, specific functions, with the only exact match similarity being that they are all delivered as a service with no tangible elements and no (or minimal) upfront investment.

Hopefully this post has helped break them down and clear any confusion you may have. As always, if you have any questions please don’t hesitate to get in touch.

Image credit: bakhtairzein/

Matthew Reeve

Content Executive

Matthew is Secura's content specialist, producing gripping, emotionally complex, edge of your seat, cloud hosting articles and videos.

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