TH5: IaaS vs PaaS vs SaaS - DevWithNehaCloud/Oracle-Cloud-Infrastructure-wiki GitHub Wiki
IaaS vs PaaS vs SaaS
Cloud services are commonly divided into three models:
- IaaS (Infrastructure as a Service)
- PaaS (Platform as a Service)
- SaaS (Software as a Service)
The main difference is who manages what.
| Component | On-Premises | IaaS | PaaS | SaaS |
|---|---|---|---|---|
| Applications | You | You | You | Provider |
| Data | You | You | You | Provider |
| Runtime | You | You | Provider | Provider |
| Middleware | You | You | Provider | Provider |
| Operating System | You | You | Provider | Provider |
| Virtualization | You | Provider | Provider | Provider |
| Servers | You | Provider | Provider | Provider |
| Storage | You | Provider | Provider | Provider |
| Networking | You | Provider | Provider | Provider |
IaaS (Infrastructure as a Service)
In IaaS, the cloud provider manages the infrastructure, while the customer manages the operating system, applications, and data.
Examples
| Service Provider | Example |
|---|---|
| Oracle Cloud Infrastructure (OCI) | Compute Instance |
| AWS | EC2 |
| Microsoft Azure | Virtual Machines |
| Google Cloud | Compute Engine |
Responsibilities
Provider Manages:
- Networking
- Storage
- Servers
- Virtualization
Customer Manages:
- Operating System
- Middleware
- Runtime
- Applications
- Data
Use Case
Use IaaS when you need full control over the server and operating system.
PaaS (Platform as a Service)
In PaaS, the cloud provider manages both the infrastructure and platform components, allowing developers to focus only on application development.
Examples
| Service Provider | Example |
|---|---|
| OCI | Autonomous Database |
| Google Cloud | App Engine |
| Microsoft Azure | App Service |
| AWS | Elastic Beanstalk |
Responsibilities
Provider Manages:
- Networking
- Storage
- Servers
- Virtualization
- Operating System
- Middleware
- Runtime
Customer Manages:
- Applications
- Data
Use Case
Use PaaS when you want to focus on coding and application deployment without managing servers.
SaaS (Software as a Service)
In SaaS, the provider manages everything and delivers a ready-to-use application over the internet.
Examples
| Provider | Example |
|---|---|
| Gmail | |
| Microsoft | Microsoft 365 |
| Salesforce | Salesforce CRM |
| Zoom | Zoom |
Responsibilities
Provider Manages:
- Applications
- Data
- Runtime
- Middleware
- Operating System
- Infrastructure
Customer Manages:
- Application Usage Only
Use Case
Use SaaS when you simply need to use a software application without managing any infrastructure or platform components.
Quick Comparison
| Feature | IaaS | PaaS | SaaS |
|---|---|---|---|
| Control Level | High | Medium | Low |
| Server Management | Customer | Provider | Provider |
| Application Management | Customer | Customer | Provider |
| Maintenance Effort | High | Medium | Low |
| Best For | System Admins | Developers | End Users |
Easy Memory Trick
IaaS
Rent the Infrastructure
- Example: OCI Compute, AWS EC2
PaaS
Rent the Platform
- Example: OCI Autonomous Database, Azure App Service
SaaS
Use the Software
- Example: Gmail, Microsoft 365, Zoom
IaaS = Infrastructure
PaaS = Platform
SaaS = Software
OCI Services Classification: IaaS vs PaaS vs SaaS
OCI provides services across Infrastructure, Platform, and Software layers. Understanding where a service fits helps in designing and managing cloud environments.
IaaS (Infrastructure as a Service)
In IaaS, Oracle provides the infrastructure, while you manage the operating system, applications, and data.
OCI IaaS Services
| OCI Service | Purpose |
|---|---|
| Compute Instance | Virtual Machine (VM) |
| Bare Metal Instance | Physical Server |
| Block Volume | Persistent Storage |
| Object Storage (Bucket) | Store files, backups, logs, images |
| File Storage | Shared File System |
| VCN | Virtual Network |
| Subnet | Network Segmentation |
| Route Table | Traffic Routing |
| Security List | Firewall Rules |
| Network Security Group (NSG) | Instance-Level Firewall |
| Load Balancer | Traffic Distribution |
| Internet Gateway | Internet Connectivity |
| NAT Gateway | Outbound Internet Access |
| Service Gateway | Private OCI Service Access |
| Dynamic Routing Gateway (DRG) | Hybrid Connectivity |
| FastConnect | Dedicated Private Connection |
Example
If you create:
- Compute Instance
- VCN
- Subnet
- Object Storage Bucket
You are using IaaS services because you are responsible for managing the OS, applications, and data.
PaaS (Platform as a Service)
In PaaS, Oracle manages the infrastructure, operating system, and platform components. You only focus on application logic and data.
OCI PaaS Services
| OCI Service | Purpose |
|---|---|
| Autonomous Database | Self-Managing Database |
| Oracle Database Service | Managed Database |
| Oracle Integration Cloud (OIC) | Application Integration |
| API Gateway | API Management |
| Oracle Analytics Cloud | Analytics & Reporting |
| Data Flow | Serverless Apache Spark |
| Data Integration | ETL Pipelines |
| OCI Functions | Serverless Computing |
| Container Engine for Kubernetes (OKE) | Managed Kubernetes Platform |
| DevOps Service | CI/CD Automation |
Example
If you create:
- Autonomous Database
- OCI Functions
- API Gateway
Oracle manages patching, backups, and infrastructure while you focus on the application.
SaaS (Software as a Service)
In SaaS, Oracle manages everything and provides a ready-to-use application.
Oracle SaaS Examples
| Oracle SaaS Product | Purpose |
|---|---|
| Oracle Fusion ERP | Enterprise Resource Planning |
| Oracle Fusion HCM | Human Capital Management |
| Oracle Fusion SCM | Supply Chain Management |
| Oracle CX Cloud | Customer Experience |
| Oracle NetSuite | Business Management Suite |
Example
If your company uses Oracle Fusion ERP, you simply log in and use the application. Oracle manages the entire backend infrastructure and platform.
Quick Classification of Common OCI Services
| OCI Resource | Category |
|---|---|
| Compute Instance | IaaS |
| Bare Metal Instance | IaaS |
| VCN | IaaS |
| Subnet | IaaS |
| Route Table | IaaS |
| Security List | IaaS |
| NSG | IaaS |
| Block Volume | IaaS |
| Object Storage Bucket | IaaS |
| File Storage | IaaS |
| Load Balancer | IaaS |
| Internet Gateway | IaaS |
| DRG | IaaS |
| FastConnect | IaaS |
| Autonomous Database | PaaS |
| OCI Functions | PaaS |
| API Gateway | PaaS |
| Data Flow | PaaS |
| OKE | PaaS |
| Oracle Analytics Cloud | PaaS |
| Oracle Fusion ERP | SaaS |
| Oracle Fusion HCM | SaaS |
| Oracle NetSuite | SaaS |
Interview Question
Is OCI Object Storage (Bucket) IaaS, PaaS, or SaaS?
Answer: Object Storage (Bucket) is an IaaS service because Oracle only provides the storage infrastructure, while you manage the files, backups, and data stored inside it.
Is Autonomous Database IaaS or PaaS?
Answer: Autonomous Database is a PaaS service because Oracle manages patching, backups, tuning, and database infrastructure automatically.
Is Oracle Fusion ERP IaaS or PaaS?
Answer: Oracle Fusion ERP is a SaaS service because it is a complete business application that users consume directly.