Single Sign-On (SSO)
Definition
Single sign-on enables access to multiple connected applications after one login.
Single sign-on allows access to multiple connected applications after logging in once with a trusted identity provider, without needing to authenticate again for each application. The applications usually maintain their own sessions.
Simply explained
You log in once at a central point and can then use multiple connected services.
Why it matters in practice
The term contributes to secure, maintainable, and high-performance web applications as well as resilient technical decisions.
Example from business
Employees log in at the identity provider and then access CRM and knowledge systems.
Limits and pitfalls
- Mistaking SSO for a specific protocol or a single shared application session and underestimating failure concentration, misconfiguration, multi-factor authentication, or offboarding.
Origin & history
SSO developed with centralized and federated identity management. SAML and OpenID Connect are common protocols; OAuth alone is not an authentication protocol.
Use in mid-sized companies
- Possible example: Employees log in at the identity provider and then access CRM and knowledge systems.
Frequently asked questions
What does single sign-on (SSO) mean?
Single sign-on allows access to multiple connected applications after logging in once with a trusted identity provider, without needing to authenticate again for each application. The applications usually maintain their own sessions. What mistakes should be avoided? Mistaking SSO for a specific protocol or a single shared application session and underestimating failure concentration, misconfiguration, multi-factor authentication, or offboarding.
Sources
- OpenID Connect Core 1.0 · OpenID Foundation, OpenID Connect Core 1.0
Source checked on 10.10.2026. Editorial usage examples are hypothetical; no evidence of real customer results.
Editorially reviewed on: