Lesson 2 of 6
Lesson 2 — IaaS, PaaS and SaaS
How much of the stack do you want to manage? Pizza-as-a-Service explains it best.
Learn it
IaaS = you rent raw machines and manage the operating system yourself.
PaaS = you upload your code and the provider runs the servers for you.
SaaS = you just use finished software in a browser, like Google Docs.
Key terms
- IaaS
- Infrastructure as a Service — rented virtual machines, storage and networks.
- PaaS
- Platform as a Service — you deploy code, the platform runs it.
- SaaS
- Software as a Service — ready-made applications delivered over the web.
- Serverless
- Code that runs per event with no server for you to manage or keep running.
- Managed service
- A component (database, queue, cache) operated for you by the provider.
Pizza as a Service
Decide how much of dinner you want to make yourself.
- 1On-premises: You make the dough, sauce, toppings, and use your own oven and dining table.
- 2IaaS: You buy a frozen pizza — the oven and table are yours, the base is provided.
- 3PaaS: Pizza delivery — you supply only the table and drinks.
- 4SaaS: You eat at the restaurant. You bring nothing but an appetite (and your data).
Same app, three models
yaml# IaaS: you own the box
vm: ubuntu-22.04
you_install: [nginx, node, certbot, security-patches]
# PaaS: you own the code
build: npm run build
start: node server.js # platform handles OS, TLS, scaling
# SaaS: you own only content
service: hosted-website-builder
you_manage: [pages, users]The application can be identical — what changes is the size of the list of things that are your problem at 3 a.m.
Try it
Match each product to its service model.
Challenge
A three-person startup is building a booking website. Recommend a service model, justify it, and say what would make you change your mind.
Pick whichever way suits you — every mode earns the same bonus XP.
Write at least 40 more characters to submit.
Mark your own work
Guided walkthrough — 0/4 clues revealed
- Clue 1 locked — reveal it only if you get stuck.
- Clue 2 locked — reveal it only if you get stuck.
- Clue 3 locked — reveal it only if you get stuck.
- Clue 4 locked — reveal it only if you get stuck.
Each clue costs 4 XP (never below 19 XP). You'd earn 38 XP right now.