The Evolution of Avionics Networks From ARINC 429 to AFDX

Signaling and inter-system communication in avionics have been crucial topics ever since electronic devices were first used in aerospace systems. To deal with the challenges introduced by the widespread use of general purpose computing in commercial avionics, standards like ARINC 419 and later on 429 were published and adopted by the industry. While in industrial use, 429 has been adapted and extended very little since the standard was formulated in the late 1970s. 429 today cannot meet challenges and new requirements generated by the use of Integrated Modular Avionics and flexible system design. AFDX combines proven safety and availability functionality with modern Ethernet technology to be able to handle today’s requirements. This paper outlines two of the most important avionics network architectures and aims at depicting the evolution of networking concepts and requirements over the course of the past 30 years. It mainly focuses on ARINC 429 and AFDX, the most prominent current and past standards, but also covers two other interesting past protocols.