Microsoft Entra ID Engineering - OAuth, OIDC, Conditional Access, and identity as infrastructure at enterprise scale. #1007513

For most of computing history, identity was a feature of applications. Each system had its own user store, its own login page, its own session mechanism. Users had to remember dozens of credentials, administrators had to provision and deprovision across every system independently, and security teams had no single place to enforce policy or investigate incidents. That model broke under its own weight.

Microsoft Entra ID Engineering is the engineer's guide to the modern alternative. Identity is infrastructure: a shared service that applications consume, that administrators manage centrally, and that security teams instrument. This book covers it end-to-end.

You'll go from the foundations — the tenant model, OAuth 2.0, OpenID Connect, and the token validation algorithm — into application integration: app registrations, MSAL across every platform, protecting APIs with scopes and roles, and workload identity federation for CI/CD and Kubernetes without secrets. Part III covers policy and governance: Conditional Access, Privileged Identity Management, entitlement management with access packages, and cross-tenant access for B2B and M&A. Part IV is production: monitoring and logging with KQL, incident response playbooks, migration from AD FS and legacy authentication, and closing patterns from real enterprise deployments.