What’s the difference between PaaS, SaaS, and IaaS? | Sailet

With the advent of cloud technologies, companies have found new ways to deploy, manage, and scale their applications and infrastructure. The three main cloud service models: PaaS (Platform as a Service), SaaS (Software as a Service), and IaaS (Infrastructure as a Service) offer different levels of control and responsibility. Let’s take a closer look at their features.

What is PaaS?

PaaS is a cloud model that provides a platform and tools for developing, testing, and deploying applications. It separates infrastructure layers, allowing developers to focus on coding the application, not managing servers and networks. PaaS is suitable for creating applications, web services, and APIs, enhancing productivity and simplifying development.

Unlike other systems, this platform does not have access to the server’s operating system, nor can you configure their configuration or perform load balancing. Your provider takes care of all these tasks. However, you have access to the tools provided by the platform: uploading your data, installing application software.

Examples of PaaS services include database processing systems, artificial intelligence platforms, and container platforms like Kubernetes. Essentially, PaaS includes any platform that can be used as a basis for application development.

Advantages of PaaS:

  1. Accelerated development: 

Provides ready infrastructure and tools, allowing developers to focus on creating application functionality, speeding up the development process.

  1. Automatic scaling: 

Automatically scales resources depending on the load, ensuring optimal performance even during sudden peak loads.

  1. Cost reduction: 

Ready infrastructure and optimized resources can reduce hardware and maintenance costs.

  1. Simplified updates and support: 

Automatic updates and maintenance of infrastructure free developers from routine tasks and ensure security.

Disadvantages of PaaS:

  1. Limited customization options: 

Using a ready platform can limit the ability to customize infrastructure and configurations, problematic for projects with specific requirements.

  1. Dependency on the provider: 

PaaS can create dependency on a specific cloud provider, complicating the process of moving to another platform or infrastructure.

  1. Limited choice of technologies: 

Some platforms may limit the choice of technologies and programming languages used.

  1. Security and confidentiality: 

Transferring data to third-party servers can raise concerns about data security and confidentiality, especially for sensitive information.

What is SaaS?

SaaS is a model where applications are provided to users over the internet by subscription. Users do not need to install and update software on their devices, as these actions are performed on the provider’s remote servers.

Typically suitable for applications that require wide distribution, such as customer relationship management, email, project management, etc.

Advantages of SaaS:

  1. Ready solution: 

No need to develop from scratch, saving time and resources.

  1. Focus on business: 

Concentration on solving business tasks without being distracted by software development.

  1. Easy access: 

Just need a browser and an internet connection to start working with SaaS.

Disadvantages of SaaS:

  1. Limited functionality: 

Your functionality is limited within the program.

  1. Dependence on the provider: 

The operation of SaaS is controlled by the supplier, and you have to rely on its reliability.

  1. Limited integration: 

Integration with other applications and services may be limited.

What is IaaS?

IaaS is a model that provides virtual computing models, such as network resources and storage. Users can create and manage infrastructure, whether servers, networks, or storage, both locally and in the cloud.

This model can be compared to a virtual «machine» from which you get computing power and can use it as you wish. You only pay for the consumed resources, while the provider monitors the equipment’s condition.

Features of IaaS:

  • Renting dedicated servers: 

You can rent virtual or physical servers and install the necessary software on them, providing flexibility and control over your infrastructure.

  • Resource management: 

IaaS providers offer special settings for efficient management of your computing resources, allowing you to divide them among projects and set access rights for different users.

  • Load balancing: 

You can evenly distribute the load between servers using balancers, ensuring more stable and efficient operation of your infrastructure.

  • Cloud storage: 

Using cloud storage, you can store files and create data backups. This provides instant access to information and the ability to store large volumes of data.

  • Disaster recovery: 

Services are provided for backing up your infrastructure and automatically transferring the load to backup systems in case of failures, ensuring data safety and quick recovery.

Advantages of IaaS:

  1. Flexibility and scalability: 

You can instantly adapt your computing resources to your needs, scaling them up or down without investing in your servers.

  1. Time and resource savings: 

With ready infrastructure and resource management by the provider, you save time and effort that would go into deploying and maintaining your servers.

  1. Backup and recovery: 

IaaS providers ensure automatic backup and recovery mechanisms, securing data and quick correction after failures.

Disadvantages of IaaS:

  1. Complexity of use: 

Effective use of IaaS requires special knowledge and skills, as it is a complex service model.

  1. Dependence on the provider: 

The quality of your infrastructure’s functioning highly depends on the reliability and responsibility of the provider—how they maintain the equipment and how often they update it. Choosing a cloud service provider requires careful consideration.


Choosing between PaaS, SaaS, and IaaS depends on your needs and priorities. PaaS facilitates application development, SaaS offers ready solutions without worries about support, and IaaS gives full control over infrastructure. Consider the advantages and disadvantages of each model when making a decision to optimally meet the requirements of your project or business.