Selection of Media Access Protocol for Distributed Digital Avionics

The paper presents the results of an ongoing research project where the objectives are to evaluate avionic network topologies and media access protocols in view of the distributed digital flight control systems (DDFCS) of high performance aircraft and to recommend a specific protocol for its prototype development. The selection of an appropriate protocol is critical for the stability of an aircraft because the DDFCS, in addition to the sampling time delay, is subject to the transport delay due to media access and message transmission in the network. The MIL-STD-1553B and SAE token ring protocols were analyzed and the analytical results have been verified by use of discrete event simulation techniques.