Ref: https://learn.cantrill.io/courses/2022818/lectures/45718075

• Summary
• Contents:

Infra Stack (or App Stack)

• Infrastructure layers when deploying a software application:
  1. Application
  2. Data (DB…)
  3. Runtime (RTE, libraries…)
  4. Container (Docker…)
  5. OS (Linux, Windows, MacOS…)
  6. Virtualization
  7. Server
  8. Infrastructure (server racks, network routers…)
  9. Facilities (building, electricity, real estate, security staff…)
• 🔧 Unit of consumption = what the customer pays for and consumes
  • Everything below the unit of consumption in the Infra Stack is managed by the vendor
  • The unit of consumption itself and everything above in the Infra Stack is managed by the customer
  • Each service model differs in its unit of consumption
• On-premises → Customers pay for everything in the Infra Stack
  • 👎 Expensive, has risks
  • 👍 Highest ownership → very flexible
• Data Center (DC) hosted → Customers pay for using facilities (fully or partially), and take care of everything else
  • Popular before cloud computing

Popular Cloud Service Models

IaaS (Infrastructure-as-a-Service)

• 🔧 Unit of consumption: OS
  • Generally, IaaS provides virtual servers/machines (VMs)
• Pricing: generally pay-as-you-go
  • Pay a fee per second/min/hour of VM use
  • No costs when not using the VM
• Lose a bit on flexibility, but gain a lot in cost & risk reductions
• One of the most popular cloud services
• e.g. Amazon EC2

PaaS (Platform-as-a-Service)

• 🔧 Unit of consumption: Runtime Environment (RTE)