Single Sign-On: Acronyms Demystified

This text discusses Single Sign-On (SSO) and its related acronyms and protocols - SAML, OIDC, and OAuth. It explains that SSO allows users to access multiple applications using one set of login credentials, improving user experience, security, and retention rates. The text then delves into the specifics of each protocol: 1. OAuth 2.0 (Open Authorization): An open-access delegation framework that uses HTTPS for authorizing devices, APIs, servers, and applications with access tokens. It enables users to grant applications access to resources without sharing their passwords. The text also explains the different actors involved in an OAuth flow and the various grant types available. 2. OIDC (OpenID Connect): An authentication layer built on top of the OAuth 2.0 framework that returns a user's identity as a JSON Web Token (JWT) called an ID Token. The text describes the primary actors in OIDC, supported flows, and how to verify the ID token before creating a session for the user. 3. SAML (Security Assertion Markup Language): An authentication protocol widely used by enterprises for enabling federated authentication. It involves three primary actors: User Agent, Service Provider, and Identity Provider. The text explains the different types of SAML flows and how to verify the validity of a SAML assertion before creating a session. The text concludes by suggesting that third-party vendors like WorkOS can simplify the implementation of SSO by offering secure, efficient, and user-friendly solutions.