What is the difference between IaaS, PaaS, and SaaS?
These are the three main cloud service models based on how much the provider manages. IaaS gives you raw infrastructure like virtual servers and you manage the rest. PaaS gives you a platform to run code without managing servers. SaaS is ready to use software you just log into. The higher you go, the less you manage.
The three models
- IaaS: raw servers, storage, and networking. Example: AWS EC2. You manage the OS and apps.
- PaaS: a platform to deploy code without handling servers. Example: Heroku or App Engine.
- SaaS: finished software over the web. Example: Gmail or Dropbox.
A simple way to remember it is IaaS gives you the building blocks, PaaS gives you a ready workspace, and SaaS gives you the finished product. More convenience means less control.
Use a food analogy if you want to stand out. IaaS is buying ingredients, PaaS is a meal kit, and SaaS is a restaurant meal. Clear analogies make interviewers remember your answer.
Common follow up questions
Related interview questions
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