IAM Study Series: Start Here

IAM shows up everywhere once you start working with enterprise systems, and the vocabulary is a minefield. Identity, account, authentication, authorization, directory, IdP, assertion, token — words that sound interchangeable but mean very different things, and mixing them up is how access reviews and incident write-ups go wrong.

I started writing these notes to pin the vocabulary down for myself, one chapter at a time, each with a single running example so the terms stay anchored to something concrete instead of floating as abstract definitions.

This is a study series. I am writing it as I learn, so it will grow. Each chapter has my handwritten notes as a one-page image, plus a short explanation.

The running example

Skyline Manufacturing — a fictional aerospace supplier, 8,000 people, 200+ apps, strict export-control requirements. John Wick — a design engineer on the wing assembly team, who needs to log in, get MFA'd, get into PLM, and stay out of payroll.

Every chapter follows John through one layer of the stack.

Chapters in this series

• Chapter 1: Identity & Authentication
• Chapter 2: Authorization, IdP & Directories
• Chapter 3: Authentication & MFA
• Chapter 4: SAML 2.0 & SSO
• Chapter 5: OAuth 2.0, Part 1

New chapters will be added to this list as I write them.