Final answer:
The Secure Data Unit (SDU) ensures the confidentiality, integrity, and authentication of data exchanged over the network in a Link 16 terminal.
Step-by-step explanation:
The Secure Data Unit (SDU) is a key component of a Link 16 terminal. Its purpose is to ensure the confidentiality, integrity, and authentication of the data exchanged over the network. The SDU encrypts and decrypts the data, protecting it from unauthorized access and tampering.
For example, in a military context, Link 16 is a tactical data link used by military aircraft, ships, and ground forces to exchange real-time situational awareness information. The SDU ensures that this sensitive information remains secure and can only be accessed by authorized users.