Single sign-on
lastmod 2025-03-27created 2025-03-272 edits
Single sign-on (SSO) is an authentication feature that makes resources on multiple computers available through a single authentication process. It is also called single account login or single authentication.
For example, if a user has to log in again to use an application such as groupware after logging in to a computer, and log in yet again to use an application on another server, the user has to manage multiple IDs and passwords. In an environment with single sign-on, the user can use all features with a single ID and password.
When single sign-on is introduced in an environment that requires security, logging in to multiple applications is simplified for convenience, but access security for the starting point of single sign-on, that is, the application or operating system that is the target of the first login, becomes important. In environments with low security risk, convenience alone may be pursued, but in environments that require security, it is necessary to strengthen security with two-factor authentication, such as using one-time passwords.
As business systems are increasingly split into multiple web applications within a company, there are packages that provide single sign-on for them. Recently, enterprise single sign-on products have appeared that support not only web applications but also terminal emulators and client-server model applications.
When introducing it, you must consider whether the applications covered by single sign-on need to be modified. If the applications need to be modified, the cost and risk of introduction can increase.
Other shared authentication schemes include OAuth, OpenID, OpenID Connect, and Facebook Connect. However, these authentication schemes should not be confused with SSO, because they require users to enter login credentials each time they access a different site or application.
See also
- OAuth
- OpenID
- OpenID Connect
- OpenPubkey SSH (OPKSSH) - Single sign-on system integrated with SSH