Which of the following operates as a guardian between two connected sites, enforcing mandatory access controls and interpreting data sensitivity levels?

The correct choice is Cross Domain Solutions (CDS), which serves a vital role in managing and securing data exchange between different security domains. When organizations need to share data across systems with varying sensitivity levels and security policies, CDS acts as a guardian that ensures these interactions occur in compliance with the defined security parameters.

CDS implements mandatory access controls by enforcing policies that dictate how information can be accessed and shared. It evaluates the sensitivity of the data being transferred and applies necessary restrictions based on pre-defined rules, preventing unauthorized access and ensuring that confidential information does not leak to less secure environments.

By utilizing a framework for interpreting data sensitivity levels, CDS supports organizations in adhering to regulations and standards for data protection. This capability is essential in environments where compliance with strict security mandates is required, such as government agencies, defense organizations, and industries handling sensitive health or financial information.

In contrast, while an identity provider (IdP) focuses on authenticating users and managing identity credentials, and directory services are key in storing and retrieving identity information, neither directly manages the inter-domain enforcement of access controls or data sensitivity interpretations comprehensively. NAC lists (often referring to Network Access Control) serve to manage endpoints accessing a network but do not function as mediators between separate security domains, particularly