Reliability Enhancement of Redundancy Management in AFDX Networks

Avionics Full Duplex Switched Ethernet is a safety critical network in which a redundancy management mechanism is employed to enhance the reliability of the network. However, as stated in the ARINC664-P7 standard, there still exists a potential problem, which may fail redundant transmissions due to sequence inversion in the redundant channels. In this paper, we explore this phenomenon and provide its mathematical analysis. It is revealed that the variable jitter and the transmission latency difference between two successive frames are the two main sources of sequence inversion. Thus, two methods are proposed and investigated to mitigate the effects of jitter pessimism, which can eliminate the potential risk. A case study is carried out and the obtained results confirm the validity and applicability of the developed approaches.