1. Infrastructure as a Service (IaaS)
Infrastructure as a Service (IaaS) is the most flexible cloud service, giving you maximum control over computing resources. In IaaS, the cloud provider manages the physical hardware, network connectivity, and data center security. Everything else—including operating systems, applications, databases, and network configurations—is your responsibility. Essentially, you are renting virtual hardware in the cloud, and how you use it is up to you.
Shared Responsibility
Provider: Physical infrastructure, network access, and data center security.
User: Operating system, applications, patches, configuration, and security.
Examples
Microsoft Azure Virtual Machines
Amazon EC2 (Elastic Compute Cloud)
Google Compute Engine (GCE)
Common Use Cases
Lift-and-shift migrations: Move existing on-premises applications to the cloud without redesigning them.
Development and testing environments: Quickly deploy or remove environments as needed while maintaining full control.
High-performance computing: Running resource-intensive workloads like simulations, scientific computing, or big data analytics.
Backup and disaster recovery: Quickly replicate infrastructure for failover purposes.
2. Platform as a Service (PaaS)
Platform as a Service (PaaS) provides a ready-to-use platform for developing, testing, and deploying applications without managing the underlying infrastructure. The cloud provider handles the hardware, network, OS, middleware, and runtime environment, so you can focus on your code and business logic.
Shared Responsibility
Provider: Physical infrastructure, network, OS, runtime, and middleware.
User: Application code, data, and user access management.
Examples
Common Use Cases
Application development: Build and deploy web apps or APIs quickly without worrying about the underlying infrastructure.
Analytics and business intelligence: Use tools for data processing, visualization, and forecasting.
IoT applications: Collect and process data from IoT devices efficiently.
Microservices architectures: Run containerized applications and services using built-in orchestration tools.
3. Software as a Service (SaaS)
Software as a Service (SaaS) delivers fully developed applications over the internet, ready to use. The provider manages everything from infrastructure to application updates. Users only need to manage their data, users, and access. SaaS requires minimal technical expertise and is quick to deploy.
Shared Responsibility
Provider: Everything, including software, infrastructure, security, updates, and patches.
User: Data input, user access, and devices used to access the service.
Examples
Microsoft 365 (Word, Excel, Teams, Outlook)
Google Workspace (Gmail, Docs, Drive)
Salesforce CRM
Zoom, Slack
Common Use Cases
Email and messaging platforms
Productivity tools and collaboration applications
Customer Relationship Management (CRM) systems
Accounting, finance, and expense tracking software
E-commerce platforms for small businesses
![saas]()
4. Choosing the Right Cloud Service
| Cloud Service | Ideal Use Cases | Examples |
|---|
| IaaS | Lift-and-shift migrations, development and test environments, high-performance computing, backup, and disaster recovery | Azure VMs, AWS EC2, Google Compute Engine |
| PaaS | Application development, analytics, business intelligence, IoT apps, microservices | Azure App Service, Google App Engine, Heroku |
| SaaS | Ready-to-use applications, email, collaboration, CRM, and finance tracking | Microsoft 365, Google Workspace, Salesforce, Zoom |
Key Takeaways
IaaS: Maximum control, you manage most of the stack.
PaaS: Focus on your applications while the provider manages the platform.
SaaS: Minimal effort, provider handles everything except your data and access.
![cloud]()