Abstract: The scheduling solution of hybrid critical messages is the key to its application in avionics systems, and increasingly dynamic applications rely more on the online solution of time-triggered scheduling. At present, time-triggered network scheduling is most-ly based on offline scheduling tables, which take a long time to generate and are difficult to adjust. In order to solve the schedul-ing table faster and make online adjustment, this paper combines the publish/subscribe architecture of the data distribution system, and constructs a time-triggered network architecture model based on publish/subscribe model. Then the online time-triggered scheduling algorithm based on unified time slots is proposed. The time is discretized into time slots with the unified maximum length, which optimizes the scheduling solution space and reduces the time of scheduling table generation. The link load is meas-ured by the time slot length and balanced in the process of scheduling to reduce the end-to-end delay of rate-constrained messages. The experimental results show that for the network with 300 messages, the scheduling solution speed of the proposed algorithm is thousands of times that of the SMT algorithm, and the worst-case end-to-end delay of rate-constrained messages is reduced by 17.4% compared with the SMT algorithm. For the network with 2000 time-triggered messages, the proposed method takes less than 100 milliseconds to generate the schedule table.

Key words: time-triggered, publish/subscribe architecture, online scheduling, time fragmentation, real-time performance