The terms “on-premises,” “IaaS” (Infrastructure as a Service), “PaaS” (Platform as a Service), and “FaaS” (Functions as a Service) refer to different deployment and service models in the realm of cloud computing and infrastructure management. Here’s an overview of the key differences between these concepts:

Aspect On-Premises IaaS PaaS FaaS
Location On-premises Cloud Data Centers Cloud Data Centers Cloud Data Centers
Ownership and Control Full control Limited control Minimal control No control (abstracted)
Responsibility Full ownership Infrastructure management Application development Function implementation
Scalability Manual, hardware purchase On-demand virtual resources Automatic, based on app demand Automatic, event-driven
Examples Traditional data centers AWS, Azure, GCP Heroku, Google App Engine AWS Lambda, Azure Functions
Management Complexity High Moderate Low Very Low
Infrastructure Details Managed in-house Managed by IaaS provider Abstracted by PaaS provider Fully abstracted by FaaS provider
Use Cases Legacy systems, data-sensitive workloads Scalable web apps, virtualized environments Web and mobile app development Event-driven, microservices
Deployment Speed Slower due to hardware provisioning Faster virtual resource provisioning Fast application deployment Instant function deployment
Resource Cost Flexibility Limited flexibility Flexible based on resource usage Resource cost bundled with platform Granular billing based on function execution
Maintenance Effort High (hardware and software) Moderate (virtual infrastructure) Low (focus on code) Minimal (purely code)