An Application Layer Gateway for Air Traffic Management Communication by Satellite

Aeronautical safety communication via satellite presents some interesting challenges, one of which is the problem of passing inelastic traffic (generated by real time events) over a limited bandwidth communication channel. Today’s aviation standards prescribe the use of a reliable transport protocol, a proposition that is inherently incompatible with inelastic traffic. Though network capacity should be sized for the normal peak load, one must assume that unusually high peak loads will occasionally occur, leading to congestion. This paper describes the concept of an application layer gateway, capable of mitigating congestion by re-ordering and, if necessary, selectively discarding messages in accordance with set rules. A demonstration test bed is described. Test results, confirming the capability of the gateway to relieve congestion, are also given.