IaaS, PaaS and SaaS: Definitions and differences
Cloud computing has enabled companies to access a number of services over the internet. This system has been set up by cloud service providers across the globe. It facilitates the use of software, applications, platforms and infrastructures to develop an organisation’s activity. These services fall into three categories: IaaS (Infrastructure-as-a-Service), PaaS (Platform-as-a-Service) and SaaS (Software-as-a-Service). Each term refers to a resource made available to users as an on-demand model. This means users do not need to invest heavily in infrastructure to host and use their services.
What are the differences between IaaS, PaaS and SaaS?
Each solution has a different resource type. Each of them has its own distribution, billing method and usage.
- Infrastructure-as-a-Service (IaaS). A set of raw IT resources offered to the user by the cloud service provider. They can be used to virtualise an infrastructure, or for resource-intensive projects — i.e. machine learning, big data, hosting, etc.
- Platform-as-a-Service (PaaS). A platform that a provider offers to its customers via the internet. It enables teams — especially developers — to build applications and software on a solution without having to maintain it. Some applications support a wide variety of programming languages, which means they deliver more flexibility than an application hosted on a local infrastructure.
- Software-as-a-Service (SaaS). This is the most popular cloud service. It is software that runs on a provider’s infrastructure. The user pays for the licence, but does not manage the data storage or physical hardware maintenance.
These different models each have their own advantages, and they do not meet the same needs.
IaaS, PaaS, or SaaS — which cloud solution should you choose?
There is no right or wrong choice — each solution has features that are adapted to different projects. Each one also brings a different layer to your information system (IS).
However, there are cloud computing solutions to suit every type of company. It all depends on the scale of your projects. Take a look below for details on each of these solutions.
1. SaaS: Simplicity on demand
If you already have an on-premises infrastructure, you may only need certain software or applications to meet specific business needs. You may also not have an infrastructure, and you may not feel the need to have one (SMEs, freelancers). In this case, a SaaS solution is the best choice for you. With it, you simply pay for your user licence by entrusting experts with hosting and hardware maintenance.
The advantages of SaaS
- It saves you time. This is the main advantage of SaaS — you get the cloud solutions you need quickly and easily, and you do not need to spend time monitoring the physical infrastructure.
- It is predictable. By paying a fixed monthly or annual subscription, you control your budget even more.
- It is simple. Choose your application or software, and distribute the user licences between your teams — it really is that quick and simple.
SaaS use examples:
- Security. Data encryption software for your transactions or to store your company's passwords, for example.
- CRM. There are many CRM software products available on the market to manage your customer data. Most of them work via an API, which makes them very easy to use.
- BPM. SaaS software represents a solid asset for managing your business processes. You can use it to centralise your data, and get a simplified overview.
There are thousands of SaaS solutions available online. However, we recommend choosing a certified provider. Our Marketplace offers a wide range of solutions from trusted partners for various needs (marketing, accounting, cybersecurity, project management, etc.). This way, you have all the tools you need to develop your IT infrastructure.
2. PaaS: The ultimate solution for your web applications
Do you have data to process, or need an environment to deploy code? If so, PaaS is the best solution for you.
The advantages of PaaS
- Optimisation. You can help your teams focus on their core business, and avoid having to maintain the platform. They will save them time as a result, and can track their work clearly.
- Centralisation. Group your information on the platform to improve collaboration between your teams.
- Cost reduction. You don’t have to invest in an IT infrastructure to host your platform, or train maintenance teams — your provider takes care of it all.
PaaS use examples:
- Development. PaaS simplifies work for DevOps engineers by enabling them to create and deploy their code on optimised environments. Some of these solutions even include CI/CD (continuous distribution), which ensures that the process of delivering applications to users is seamless. These solutions are also compatible with a wide variety of programming languages. This is the most popular use for PaaS services.
- CRM. With these solutions, you can improve how you manage customer data. CRM tools have optimised interfaces and low-code building modes, so non-technical employees can optimise their applications. Salesforce is a great example of this platform type.
- Data management. There are cloud platforms available to help you exploit your data. For example, Apache Kafka helps you structure your data streams, and extract key information on your applications.
Even though it’s getting easier to use, PaaS is not suited to all companies. It improves your time to market, and reduces your overall costs. However, most of the time it requires teams that are trained to use it.
3. IaaS: Scalability for complex projects
Infrastructure as-a-Service is a simple way for organisations to get additional resources that meet their needs. With this service, the end user can develop their projects without having a local infrastructure. IaaS solutions can be included in a public, private or hybrid cloud model. A cloud service provider hosts physical hardware in a datacentre.
The advantages of IaaS
- Scalable. With this model, you can quickly ramp up the power on projects that are facing critical workload peaks. This means you get more responsiveness to ensure business continuity. This flexibility will give you the ultimate peace of mind, especially if your projects include sensitive data.
- Customisable. You can build a virtual infrastructure that fits your needs, and get a catalogue of resources.
- Accessible. Maintaining your own physical infrastructure requires heavy investment. By outsourcing this type of resource to a cloud provider, you can get the same services at a lower cost.
IaaS use examples:
- Hosting services. Make your complex websites, applications and software accessible. This model is suitable for a resource-intensive set of IT services.
- Resilience. You can use IaaS to build a model for storing and recovering your data (backups) in the event of an incident. A disaster recovery plan (DRP) is an essential element for ensuring both business continuity and high availability for your web applications.
- Developing artificial intelligence (AI). This technology uses a lot of resources (CPU, RAM, storage space, bandwidth) because it involves storing and analysing high volumes of data (big data), as well as training machine learning algorithms. This is why additional resources available at any time are a real asset for your AI projects.
Consequently, an IaaS solution is an important tool for developing web projects that require responsiveness. It is suitable for large-scale projects, and requires teams with the knowledge to apply it within your company. Some steps, like machine virtualisation (via VMware) or containerisation (with Kubernetes), are complex processes. Please refer to our range of guides and blog posts for further information on these topics.
By outsourcing your services (SaaS, PaaS or IaaS), you can access technologies and resources at a lower cost. You can also get them up and running much quicker than you would if you were investing in an on-premises infrastructure. OVHcloud offers all of these cloud computing services in a sovereign, open cloud — so that you have full control over your data. We support you in your cloud migration with a range of trusted solutions. You can explore all of our Bare Metal Cloud, Public Cloud and Hosted Private Cloud solutions to launch your projects.