SCIM (System for Cross-domain Identity Management) and SSO (Single Sign-On) are two important protocols in identity and access management. While SCIM is designed to manage user identities across different cloud applications, ensuring consistency and accuracy of user data throughout their lifecycle at an organization, SSO focuses on authentication, allowing users to access multiple applications with a single sign-in process. SCIM uses standardized schema and RESTful API to automate provisioning tasks, reducing admin overhead for IT teams when managing large numbers of users. It supports CRUD operations such as creating, reading, updating, and deleting user accounts. On the other hand, SSO relies on a central identity provider (IdP) that authenticates users and grants them access to multiple apps without needing to re-authenticate. Some popular protocols enabling SSO include SAML, OpenID Connect, and WS-Federation. SCIM complements SSO by ensuring user information is consistent across various systems connected to the IdP, while SSO handles the authentication process for users accessing these systems.