wilamowski-b-m-irwin-j-d-industrial-communication-systems-2011

24
Embedded Networks
in Civilian Aircraft
Avionics Systems
Christian Fraboul
Université de Toulouse
Fabrice Frances
Université de Toulouse
Jean-Luc Scharbarg
Université de Toulouse
24.1 Introduction.....................................................................................24-1
24.2 Avionics Systems Evolution and ARINC Context.....................24-2
24.3 Classic Avionics and ARINC 429.................................................24-3
24.4 Integrated Modular Avionics........................................................24-4
24.5 ARINC 629 Multiplexed Data Bus...............................................24-5
Basic Protocol. •. Combined Protocol
24.6 ARINC 664: Avionics Full-Duplex Ethernet..............................24-7
Full-Duplex Switched Ethernet. •. The ARINC 664 Standard. •. .
Virtual Link Paradigm. •. Virtual Link Properties. •. .
Network Redundancy for Safety and Fault Tolerance
24.7 AFDX End-to-End Delay Analysis.............................................24-13
24.8 Conclusion......................................................................................24-13
Abbreviations.............................................................................................24-14
References..................................................................................................24-15
24.1 Introduction
The evolution of civilian aircraft avionics systems is mainly due to increasing complexity, which is
illustrated by a larger number of integrated functions, a growing volume of exchanged data, and a multiplication
of connections between functions. Consequently, the growth in the number of multipoint
communication links could not be taken into account by classic avionics mono-emitter data buses (such
as ARINC 429 [ARI01]). The first solution proposed for the Boeing 777 led to the design of a new multiplexed
data bus based on CSMA-CA medium access control (ARINC 629 standard [ARI99]). The solution
adopted by Airbus for the A380 consists in the utilization of a switched Ethernet technology (called
avionics full-duplex switched Ethernet [AFDX]). This allows a reuse of development tools as well as of
existing communication components while providing better performance; it has been standardized in
ARINC 664 [ARI02,ARI03]. This new communication standard represents a major step in the deployment
of modular avionics architectures (integrated modular avionics: IMA ARINC 651 [ARI91] and 653
[ARI97]). However, the main problem lies in the indeterminism of the switched Ethernet and a network
designer must prove that no frame will be lost by the AFDX (no switch queue overflow) and must evaluate
the end-to-end transfer delay through the network (guaranteed upper bound and distribution of
delays) according to given avionics applications traffic.
While other means of data communication have been, or could be, used in the context of avionics systems
such as automotive field buses (CAN and FlexRay [CAN93,FCS04]) and real-time buses (TTP and
24-1
© 2011 by Taylor and Francis Group, LLC