Single Sign-On looks easy—until it isn’t.
Most teams can make a login screen work. Many can integrate an IdP. Very few truly understand what happens after authentication: how identity is brokered, how users are provisioned safely, how sessions and logout propagate across systems, and why production identity failures are so difficult to diagnose.
This book is written for engineers and architects who want to build identity systems that don’t break.
What This Book Is Really About
This is not another “how to configure SSO” guide.
This book is about enterprise identity brokering—the discipline of placing a trusted intermediary between applications and external identity providers, and using that broker to control authentication, authorization, provisioning, lifecycle, and auditability without hard-coding identity logic into every app.
Using Spring Boot, Spring Security, Keycloak, and Okta (SAML 2.0), you will learn how real-world identity systems behave under load, during failures, and across organizational boundaries.
You will see identity as a system of protocols, state, trust, and lifecycle—not just login screens and tokens.
Why This Book Exists
There are excellent books on Spring Security.
There are excellent books on Keycloak.
There is extensive documentation for Okta.
But production systems do not use these tools in isolation.
In real enterprises:
- Identity is federated across companies
- Users are created dynamically
- Attributes arrive late—or incorrectly
- Logout is unreliable
- Audit trails matter
- Compliance teams ask uncomfortable questions
- And failures surface months after go-live
This book fills the gap between documentation and production reality.
What You Will Learn
By the end of this book, you will be able to:
- Design an identity brokered architecture instead of coupling apps directly to IdPs
- Run Keycloak as a standalone enterprise Identity Provider
- Build a local user directory with Spring Boot and MySQL
- Integrate Spring Security applications using Keycloak-native authentication
- Federate external identity using Okta SAML 2.0
- Configure SAML attribute statements correctly for enterprise use
- Implement Just-In-Time (JIT) user provisioning
- Write Keycloak First Broker Login and Post Login authenticators
- Trace full login and logout flows at the HTTP, cookie, and session level
- Understand why logout breaks—and how to design around it
- Diagnose identity failures using protocol-level thinking, not guesswork
How This Book Is Different
This book is:
- Protocol-first, not UI-first
- Failure-aware, not happy-path only
- Production-oriented, not demo-driven
- Architectural, not checkbox-based
You will see:
- Real HTTP call sequences
- Cookie and session behavior explained
- SAML requests and responses dissected
- Identity flows visualized with diagrams
- Common enterprise failure modes called out explicitly
Every chapter builds mental models—not just configurations.
Who This Book Is For
This book is ideal for:
- Senior Software Engineers
- Enterprise & Solution Architects
- Identity & Access Management (IAM) practitioners
- Platform and Security Engineers
- Tech Leads responsible for SSO in production
- Architects migrating legacy authentication systems
- Anyone who has ever said:
“SSO works… except sometimes.”
If you have ever debugged a broken login at 2 a.m., this book was written for you.
What You Will Walk Away With
You will not just know how to configure identity.
You will understand:
- Why identity systems fail
- Where to place responsibility
- How to reason about trust
- How to design for change
And most importantly—you will be able to explain identity systems clearly to engineers, auditors, and leadership alike.
