An Introduction to OpenID Single Sign-On (SSO)
Security Boulevard, Thursday, November 20th, 2025
Okay, so you're probably wondering what OpenID SSO actually is, right? It's not as scary as it sounds, I promise! Think of OpenID Connect as a translator. It sits on top of OAuth 2.0, which is mostly about letting apps access stuff, and makes sure everyone knows who you are. It lets apps confirm your identity based on a central server doing the authentication.
It's all about identity and info, not just permissions.
- OpenID Connect is an authentication layer that builds on top of OAuth 2.0.
- Apps use it to verify who you are, kinda like showing your id.
- Unlike OAuth 2.0, which focuses on what apps can do (authorization), OpenID Connect is about who is doing it (authentication). (How OpenID Connect Works - OpenID Foundation)
Single Sign-On (sso) is pretty simple; it's basically using one login for everything. Instead of a million passwords, you just need one to get into all your apps. According to Mimecast Support - it simplifies your sign-in experience.