What is the military encrypted mode in the IFF system?

The military encrypted mode in the Identification Friend or Foe (IFF) system is Mode 4. This mode uses a cryptographic system to provide secure identification, ensuring that only designated friendly units can respond to and be recognized by radar and other surveillance systems. The encryption helps protect against enemy forces attempting to spoof or jam the identification signals, making Mode 4 a critical component for maintaining situational awareness and operational security in military operations.

In contrast, Mode 2 and Mode 3/A are used primarily for civilian aircraft identification and do not utilize encryption to the same level as Mode 4. Mode 5, while also an advanced identification mode, is designed to enhance tracking and integrate with newer systems, but it is not specifically categorized as the encrypted military mode in the way that Mode 4 is recognized.