Yksittäiskirjautumisen

Yksittäiskirjautuminen, often abbreviated as SSO, is an authentication scheme that allows a user to log in with a single set of credentials to gain access to multiple independent software systems. Instead of requiring separate usernames and passwords for each application, a user authenticates once to an SSO service, which then grants them access to other connected applications without requiring them to re-authenticate.

The core principle of SSO involves a trusted identity provider and one or more service providers. When a user attempts to access a service provider, the service provider redirects the user to the identity provider for authentication. Upon successful authentication, the identity provider issues a security token to the user's browser or application. This token is then presented to the service provider, which verifies its authenticity and grants the user access.

SSO offers several benefits, including improved user experience by reducing the number of passwords users need to remember and manage, and increased security by minimizing password fatigue, which can lead to weaker password practices. It also streamlines IT administration by centralizing user management and authentication processes. Common SSO protocols include SAML (Security Assertion Markup Language), OAuth, and OpenID Connect. Many organizations implement SSO solutions to enhance both productivity and security within their digital environments.