Cloud Service Models Tutorial

In this cloud training tutorial, I’m going to cover the different Cloud Service Models. Scroll down for the video and text tutorial.

This is part of my ‘Practical Introduction to CloudComputing’ course. Click here to enrol in the complete course forfree!

Cloud Service Models Video Tutorial

YouTube video

NIST defines three service models of how Cloud services can be offered:

  • Infrastructure as a Service (IaaS)
  • Platform as a Service (PaaS)
  • Software as a Service (SaaS)

I’m going to have individual tutorials where we’re going to cover each of the three different service models in detail.

Cloud Service Models

Large cloud service providers are not going to offer just one service. Typically, they’re going to offer multiple models of service.

Let’s take a look at AWS. On the AWS site, if you click on Services up in the top left, you can see that AWS has got heaps of available services. They have got all the different types of models.

Microsoft got Microsoft Azure for IaaS and PaaS services, and they’ve also got Microsoft Office 365 which is a Software as a Service. You might have smaller cloud providers who might specialize in just one, but the big players will offer multiple different services.

The three models define where the customer and provider areas of responsibility are and at what level the customer gains access to the service. The three models are built on top of one another.

  • SaaS at the top
  • PaaS at the middle
  • Iaas at the bottom

Cloud Service Models 1

Data Center Stack

To explain this we need to start off by looking at the Data Centre Stack. At the bottom of the stack, we’ve got the Facility, it is the actual physical location, with the power and the cooling.

Data Center Stack

The next level up, we’ve got the Network infrastructure, our routers, switches, firewalls, etc., belong here. The next level up is our Storage system, we’re talking about physical things at these levels right now.

Then we have got Compute which is our servers, then the Hypervisor on top of there, so getting into the software level now.

On top of the Hypervisor we’ve got the Operating System, then we’ve got our Applications, and finally our Data.

When we’re looking at the different models that are available for Cloud, it’s easier if we look at a Data Centre Stack in order to understand.

There are two different deployment models namely:

  • Traditional models (On Premise and Colo)
  • Cloud models

We’ll look at the Data Center Stack, and in there we’ll see what is the following:

  • Customer area of responsibility
  • What the customer manages
  • What the provider manages

On Premise

Starting off with On Premise, obviously, the customer manages everything. There is no Cloud provider when we’re using On Premise.

On Premise


Moving on to a Colo facility, again this is a traditional model and this does not count as Cloud. With Colo, the facility is going to be provided by the provider and they’ll make sure that network connections are available there as well.

The customer will negotiate a network connection from one of the network providers. All of the other levels in the stack, from Storage, Compute, Hypervisor, Operating System, Applications, and Data, the equipment is going to be owned by and managed by the customer.


IaaS Infrastructure as a Service

The next model to look at is our first Cloud model, which is Infrastructure as a Service. With Colo, we’ve got the providers Facility, but the hardware equipment in the Facility is ours from the customer point of view.

With Cloud, it’s not just the facility that is owned and run by the provider, but the hardware equipment is owned and maintained by the Cloud provider as well. The Facility, the Network hardware, the Storage hardware, the Compute hardware, and Hypervisor software are all owned and maintained by the provider.

The Operating System will also be installed by the provider and we will get access from the Operating System level. Whoever patches the Operating Systems depends on a particular provider, they might do the patching for you or maybe you have to do the patching.

Everything above the Operating System is going to be customer responsibility. The customer is going to be installing their own applications and managing their own data. If we look at where the customer actually gets access with IaaS, they will get access from the Operating System level.

IaaS Infrastructure as a Service

If it’s a Windows server the customer will be able to Remote Desktop into the actual Desktop, the Operating System, and manage everything up from there.

PaaS Platform as a Service

The next model we have, and this is the one that actually can be quite confusing is PaaS, Platform as a Service. With Platform as a Service, the level goes up a bit in the Data Centre Stack. The provider is going to manage from the Facility up to the Operating System.

PaaS Platform as a Service

The customer looks after the Applications and Data. Platform as a Service is used for developing applications. The customer will come into a Custom Environment which is on top of the Operating System.

PaaS Platform as a Service 1

It’s not like with IaaS where they can get access at the desktop level, they’re going to come into a purpose-built environment which is designed for building applications.

SaaS Software as a Service

The last model is Software as a Service, and with Software as a Service, the provider is going to manage everything from the Facility up to the Data level.

SaaS Software as a Service

Software as a Service is a cloud-based software. For example, Microsoft Office 365 and Salesforce. The customer is going to come in at the Application level and they’re going to use the application. They can also have their own data in there, but everything is going to be managed by the provider.

That was just a quick introduction to the different models. In the next tutorials, I’ll explain these in a lot more detail and I’ll also show you how they work.

Additional Resources

Different Types Of Cloud Computing Service Models:

Cloud Service Models:

This is part of my ‘Practical Introduction to Cloud Computing’ course. Click here to enroll in the complete course for free!

Libby Teofilo

Text by Libby Teofilo, Technical Writer at

With a mission to spread network awareness through writing, Libby consistently immerses herself into the unrelenting process of knowledge acquisition and dissemination. If not engrossed in technology, you might see her with a book in one hand and a coffee in the other.