Which concept enables authentication across security domains, supporting resource access across domains?

Which concept enables authentication across security domains, supporting resource access across domains?

• A. Cross-Domain Connections
• B. Directory Services
• C. Federation of Identity (FIdM)
• D. Peering

Answer: (C)

Federation of Identity enables authentication across security domains by establishing trusted relationships so a user authenticated in one domain can access resources in another without re-authenticating. In practice, an identity provider in the user’s home domain vouches for who the user is and issues a token or assertion that a service in the target domain accepts. Standards such as SAML, OAuth, and OpenID Connect support this, making it possible to achieve single sign-on across organizations and domains. This approach directly addresses the need to authenticate across domains and grant resource access in multiple security boundaries. The other options don’t fit the cross-domain authentication goal: Directory Services manage authentication within a single domain, Cross-Domain Connections suggests general network links rather than trust and identity sharing, and Peering refers to network connections between providers rather than identity and access management.

Federation of Identity enables authentication across security domains by establishing trusted relationships so a user authenticated in one domain can access resources in another without re-authenticating. In practice, an identity provider in the user’s home domain vouches for who the user is and issues a token or assertion that a service in the target domain accepts. Standards such as SAML, OAuth, and OpenID Connect support this, making it possible to achieve single sign-on across organizations and domains.

This approach directly addresses the need to authenticate across domains and grant resource access in multiple security boundaries. The other options don’t fit the cross-domain authentication goal: Directory Services manage authentication within a single domain, Cross-Domain Connections suggests general network links rather than trust and identity sharing, and Peering refers to network connections between providers rather than identity and access management.