IaaS Vs PaaS Vs SaaS
While working with any of the cloud providers we usually come across these terms in real life scenarios. IaaS, PaaS and SaaS are the cloud service models provided by any of the cloud service providers like AWS or Azure. IaaS vs Pass Vs SaaS is a very meaningful comparison when you start to learn about cloud computing and it could lead to better understanding of the cloud concepts.
Infrastructure as a service (IaaS):
We often use some hardware components to make out application successful. These could be physical servers which can be used to host the web server or DB server. Or it could be the internet router or switches which could be used to route the traffic to these servers.
It could be quite cumbersome and time consuming to maintain these hardware. And it would result in high costs if we want to scale up or scale out the capacity.
But with the introduction of cloud providers like AWS or Azure provisioning a server is just a matter of time. And you can have your own server hosted with any amount of desired capability in no time.
The best part of this model is you have to pay only for the capacity which you are consuming.
Platform as a service (PaaS)
To develop a full fledged service we have to use many software like SQL server. Cloud providers provide out of the box support to host these services or platform in their environments.
We can say that PaaS is the super set of the IaaS.
Software as a Service (SaaS)
SaaS has a very good examples as Office365 or Google Docs. Before the existence of cloud we had to install these software on our servers or computers to use them. This is not the case anymore, we can use these software now with the minimum requirement of having an internet connection and a browser installed.
All these software are provided as service to the end user. Apart from these software, now most of the enterprise software are provided as SaaS service. For example, salesforce.
The onus to upgrade hardware and software lies on the software provider. We as a consumer have to use it on the pay as use basis.
Function as a Service (FaaS)
We can run our code in the cloud infrastructure. This has coined a new term in cloud terminologies known as serverless.
The code can be deployed as function to be invoked as web API or as a trigger to some other action in the cloud infrastructure. There would not be any bottle necks for the code in form of infrastructure as it is backed by the enormous capabilities of the cloud providers.
Below figure summarizes and helps to you understand all of the service models with quick points with relative to Azure cloud. This image can help you to have IaaS vs Pass Vs SaaS comparison with examples.
Shared responsibility model
When it comes to maintain and updated the services in the cloud platform, it becomes the shared responsibility of the user and the cloud provider based on the service model.
As far as on premise is concerned, everything is responsibility of the administrator. It includes right from updating the software, applying patched, keeping the latest OS version and so on.
For IaaS the onus to have the updated physical infrastructure is on the cloud provider.
Below figure gives you more detailed description of the Shared responsibility model in IaaS vs PaaS vs SaaS comparison.
Conclusion:
Services are the core of any cloud provider and there are three main ways to go about it.
- IaaS provider servers, storage and networking as a service
- PaaS is a superset of IaaS and also includes middleware, such as database management tools.
- SaaS is when a service is built on top of PasS, like Office 365.
- Serverless or FaaS means that you don’t have any servers. Let’s a single function be hosted, deployed, run and managed on its own.