Contemporary airborne radio networks are usually implemented using omnidirectional antennas. Unfortunately, such networks suffer from disadvantages such as easy detection by hostile aircraft and potential information leakage. In addition, tactical links used for military communication rely on NATO-specific standards such as Link 16, which are becoming outdated. 

To this end we are investigating the feasibility of replacing omnidirectional communication with directed communication, which will address the disadvantages mentioned above. In addition, we definine a communication architecture based on the conventional Ethernet and TCP/IP protocol stack, which will ease management and interoperability with existing Internet-based system 

In this report, we briefly review the TCP/IP stack and the services offerd at each layer of the stack. Furthermore, we review existing litterature involving mobile ad hoc network (MANET) protocols used for airborne networks along with various performance studies in the same area. Finally, we propose a novel MANET routing protocol based on directional antennas and situation awareness data that utilizes adaptive multihop routing to avoid sending information in directions where hostile nodes are present. 

Our protocol is implemented in the OMNEST simulator and evaluated using two realistic flight scenarios involving 8 and 24 aircraft, respectively. The results show that our protocol has significantly fewer leaked packets than comparative protocols, but at a slightly higher cost in terms of longer packet lifetime.