There are usually 3 cloud services categories – IaaS, PaaS and SaaS and it is crucial to understand the differences between these to make the right technology decisions.
Let’s review IaaS vs. PaaS vs. SaaS in more detail below.
Infrastructure as a Service (IaaS)
IaaS is the most flexible category of cloud services. With IaaS, you have complete control over the infrastructure services like virtual machines, storage, networking and operating systems. This model eliminates the requirement to buy hardware. Instead you will be renting the infrastructure and accessing it over the internet.
IaaS is a shared responsibility model with the cloud services provider (CSP). The CSP ensures that the service is highly available. It is your responsibility to patch and upgrade the system and ensure that it is available to your customers.
Some of the common use cases are:
- Migration of applications from on-premises to the cloud
- Running development and testing environments
- Backup
- Storage
Platform as a Service (PaaS)
PaaS allows you to develop, test and deploy your applications without managing the underlying infrastructure. For example, you can deploy a web application without installing the operating system and worrying about upgrading the system.
Cloud features like scalability, high availability and resiliency are included in PaaS which reduces the coding complexity and administrative overhead for businesses.
Software as a Service (SaaS)
SaaS is software that is centrally hosted and offered as a subscription to the end users. Some examples of SaaS are Salesforce CRM, Office 365, Box, Google Apps, Netflix.
Customers can quickly realize value with minimal management with SaaS.
Below is a good depiction the customer’s responsibilities within each category:
