Service Models

IaaS (Infrastructure as a Service)

Includes

• Virtual machines
• Storage
• Networking
• Firewalls
• Load balancers

Your Responsibilities

• Operating system
• Runtime
• Scaling
• configure with autoscaling groups, etc...
• Applications
• Data

Provider Responsibilities

• Physical servers
• Data centers
• Networking hardware
• Virtualization layer

PaaS (Platform as a Service)

Includes

• Managed OS
• Managed runtime (Node, Java, Python, etc.)
• Auto scaling by provider (you define limits or policies)
• Built-in monitoring

Your Responsibilities

• Application code
• Application configuration
• Data

Provider Responsibilities

• Infrastructure
• Operating system
• Runtime
• Scaling
• Platform-level security
• Platform availability

SaaS (Software as a Service)

Includes

• API access
• Application access

Example

• Gmail
• Meta Platforms (Facebook)
• Salesforce

Your Responsibilities

• User configuration
• Data

Provider Responsibilities

• Everything

Responsibilities Comparison

Layer	IaaS	PaaS	SaaS
User Configuration	You	You	You
Data Ownership	You	You	You
Application Code	You	You	Provider
Runtime	You	Provider	Provider
OS	You	Provider	Provider
Scaling	You	Provider	Provider
Infrastructure	Provider	Provider	Provider