It is a netted, time division link operating in the UHF band at 5,000 bits per second.
Link 4A TADIL C is one of several Tactical Data Links now in operation in the United States Armed Services and forces of the North Atlantic Treaty Organization (NATO).
Link-4A plays an important role by providing digital surface-to-air, air-to-surface, and air-to-air tactical communications.
The use of Link-4 has since been expanded to include communication of digital data between surface and airborne platforms.
Link 4C uses F-series messages and provides some measure of ECM resistance.