Abstract:
The switched Ethernet control system is chosen as study object.In view of the interior queuing delay in switches using IEEE 802.1p priority scheduling protocol,the scheduling improvement idea is proposed,and hard real-time and non hard real-time data flow are managed respectively.A typical switched Ethernet model with tree topology is designed,the maximum delay of periodic real-time data frame in every transmitted part after priority scheduling is calculated,and the basic conditions in improved priority scheduling protocol are derived.The OPNET software simulation shows that the suitable improvement of IEEE 802.1p priority scheduling protocol can improve the real-time performances of hard real-time data transmission in the industrial Ethernet.