What is Single Sign-On (SSO)
Security Boulevard, Friday, August 22nd, 2025
Single Sign-On (SSO) [GO1] is an authentication model in which a user logs in once with a set of credentials to gain access to multiple applications. It forms a key part of many identity and access management (IAM) systems.
Rather than needing a specific username and password for each login, SSO offers single-click access to all authorized tools securely and without redundancy.
For example, take the case of a user logging into a corporate session at the beginning of work hours. As soon as they are authenticated, they can open their email, navigate to a document in cloud storage, look at updates of a project management tool, or look at CRM records without logging in again.
Web SSO is the most common type used in cloud-based enterprise applications, where access to multiple web apps is granted via a single authentication event. Web SSO is the primary focus of this page; however, we will also briefly explore other types of SSO.