Experimental encryption of aircraft communications addressing and reporting system (ACARS) aeronautical operational control (AOC) messages

As civil controlled airspace moves toward requiring new communication capabilities, the military will need to equip their aircraft if worldwide, unrestricted airspace access is to be maintained. The USAF has built a Reconfigurable Cockpit and Avionics Testbed (RCAT) with VHF, HF and SATCOM data links and ground stations to demonstrate the utility of these data links. This facility has been used to evaluate techniques available to encrypt ACARS data link messages. This paper discusses the results of these demonstrations and documents the strengths and limitations of the "commercial-off-the-shelf" (COTS) equipment and infrastructure for security of military AOC messages. It also hopes to stimulate discussion among military users about requirements for their use of ACARS.