Which component of Link 16 assists in managing the link's operational security?

The component of Link 16 that plays a key role in managing the link's operational security is the Authentication Protocol. This protocol is essential because it ensures that only authorized users can access and transmit information over the Link 16 network. It helps to verify the identity of entities communicating within the network, thereby protecting sensitive data from unauthorized access.

The Authentication Protocol works by requiring participants to present valid credentials, ensuring that all communication is between verified and legitimate users. This process enhances the security of the entire system and is vital in military operations where data integrity and confidentiality are crucial.

In contrast, the other options, while related to Link 16's overall functionality, do not specifically focus on the operational security management aspect as directly as the Authentication Protocol does. For instance, the Secure Data Unit ensures data is transmitted securely, but its focus is more on the data itself rather than access authorization. The Link Access Protocol pertains to how devices access the link and manage communication traffic, but it doesn't inherently protect against unauthorized access. Lastly, the Encryption Key Manager is critical for providing secure encryption keys but does not manage the operational security aspects as effectively as the Authentication Protocol.