Introduction

In this tutorial, we will delve into the three main service models of cloud computing: Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). Our goal here is to understand what these services are, how they differ, and where they are used.

By the end of this tutorial, you will have a clear understanding of the differences between IaaS, PaaS, and SaaS, and you'll be able to identify real-world examples of each.

Prerequisites: Basic understanding of cloud computing.

Step-by-step Guide

Infrastructure as a Service (IaaS)

IaaS provides virtualized computing resources over the internet. It is an instant computing infrastructure, provisioned and managed over the internet.

Example: Amazon EC2, Google Compute Engine (GCE)

Best practices and tips

• Use IaaS if you want to maintain maximum flexibility and management over your IT resources.
• IaaS is great for temporary, experimental, or unexpected workloads.

Platform as a Service (PaaS)

PaaS provides a platform allowing customers to develop, run, and manage applications without the complexity of building and maintaining the infrastructure.

Example: Google App Engine, Red Hat OpenShift

Best practices and tips

• Use PaaS if you want to speed up application development and deployment, and simplify administrative tasks.
• PaaS is great for developers as it allows them to focus on coding, without worrying about the infrastructure.

Software as a Service (SaaS)

SaaS is a software distribution model in which a third-party provider hosts applications and makes them available to customers over the internet.

Example: Google Apps, Salesforce, Dropbox

Best practices and tips

• Use SaaS if you want to use applications over the internet on a pay-as-you-go basis.
• SaaS is great for end-users as it allows them to use the software without worrying about the underlying infrastructure.

Code Examples

As the concepts of IaaS, PaaS, and SaaS are more theoretical and don't involve direct coding, we won't have code snippets in this tutorial.

Summary

In this tutorial, we have learned about the three main service models of cloud computing: IaaS, PaaS, and SaaS. IaaS is about getting infrastructure, PaaS about getting the platform, and SaaS about getting software as a service.

Next steps for learning would be to delve deeper into each service model and explore how to work with them in real-world scenarios.

Practice Exercises

1. Identify which service model (IaaS, PaaS, SaaS) would be most appropriate for the following scenarios:
2. You're starting a new business and need a CRM solution, but don't want to manage any hardware or software.
3. You're a developer who wants to focus solely on coding your application, and not worry about infrastructure.

4. Your company needs extra servers temporarily to handle the increased traffics during the holiday season.

5. For each of the service models, find an additional real-world example not covered in this tutorial.

6. Think of a scenario where a combination of IaaS, PaaS, and SaaS could be used together.

Solutions with explanations

2. SaaS would be the most appropriate for the CRM solution.
3. PaaS would be the most suitable for the developer scenario.

4. IaaS is the best option for temporary server needs.

5. Additional examples:

6. IaaS: Microsoft Azure
7. PaaS: AWS Elastic Beanstalk

8. SaaS: Microsoft Office 365

9. A scenario where all three services could be used together might be a web-based business that uses IaaS to maintain its server and network, PaaS for environment setup and development, and SaaS for its customer relationship management system.