In the realm of B2B SaaS, secure and efficient authentication is paramount. Open-source Single Sign-On (SSO) solutions provide a cost-effective and flexible alternative to commercial offerings, empowering businesses to tailor their authentication infrastructure to specific needs. This article delves into a detailed technical comparison of leading open-source SSO providers, examining their architecture, protocols, features, and ideal use cases. We’ll cover: Gluu Server Keycloak LemonLDAP::NG OpenIAM Dex Choosing the Right Solution