Identity and access management between multiple users and multiple applications has become a mandatory requirement for Company XYZ to fight against ever increasing cybersecurity threats. To achieve…

OAuth 2.0 is strictly a delegation-based authorization framework and does not define an authentication mechanism or convey identity - using it alone cannot fulfill the authentication requirement.

OpenID Connect adds an authentication layer on top of OAuth 2.0 and handles identity verification, but it does not natively carry rich authorization assertions and is not the canonical enterprise federated identity and SSO standard for multi-application environments.

OpenID (1.x/2.x) is the legacy authentication protocol superseded by OpenID Connect; it lacks enterprise federation features, is no longer actively maintained, and does not support the authorization assertion exchange needed.

SAML 2.0 (Security Assertion Markup Language) exchanges signed XML assertions between an Identity Provider and Service Providers, covering both authentication (who the user is) and authorization (what they can access) in a single federated transaction. It natively supports enterprise SSO workflows and integrates with MFA mechanisms at the IdP layer, directly matching all requirements described. It is the predominant standard for enterprise-grade federated identity and cross-domain trust.