保证速率的AFDX交换机实时调度算法

针对AFDX(Avionics Full Duplex Switched Ethernet)网络关键技术——交换机实时调度算法,提出一种保证速率的优先级实时调度算法(PRTRG,Priority Real Time sched-uling algorithm based on Rate-Guaranteed),并运用网络演算理论分析了此调度算法的实时性.在AFDX网络典型配置下,与(FIFO,First In First Out)结果进行分析对比,证明PRTRG算法有效地减少了高优先级数据的端到端延迟上界,同时保证了低优先级数据端到端延迟的确定性,并且阻止了数据流拥塞的扩散,在交换机内部实现了流量隔离.

Real time scheduling algorithm based on rate-guaranteed in AFDX switch

Real time scheduling algorithm used in avionics full duplex switched Ethernet (AFDX) switches was studied, which is a key technique in AFDX. A priority real time scheduling algorithm based on rate-guaranteed(PRTRG) was proposed. Real time performance of PRTRG was analyzed using network calculus theory. Upper delay bounds with first in first out(FIFO) scheduling under a typical topology configuration were compared. The results confirm that PRTRG algorithm can effectively decrease the upper delay bounds of high priority data without losing the determinism of low priority data. At the same time, PRTRG algorithm prevents the congestion of one flow from spreading to another, and isolates the flow in the switch.