Mitigation of Sequence Inversion in AFDX based on Time-triggered Scheduling

Although Avionics Full Duplex Switched Ethernet (AFDX) obeys the aircraft data network protocol, there is data frame loss due to the problem of sequence inversion in AFDX. This problem can be solved by improving the time tightness of data frame. We proposed a time-triggered scheduling method to optimize the data frame scheduling strategy in the source sender and switches. This method alleviates the sequence inversion caused by the congestion of output ports by determining the scheduling matrix and prioritizing virtual link (VL). The comparative analysis results show two conclusions. First is that the end-to-end worst-case delay obtained by the time-triggered scheduling method in high-load AFDX networks is reduced by 13.66% and 35.55% compared to forwarding delay analysis (FA) and network calculus (NC). Second is that the time-triggered method minimizes the transmission delay difference of adjacent data frames to the limit of local synchronization (LS) method.