Research On Time-Sensitive Network Scheduling Algorithm Based On Gated Shaping

With the rapid development of industrial automation,the need for communication integration between industrial IT(Information Technology)networks and OT(Operational Technology)networks has become more urgent.In the industrial IT network and OT network converged communication scenario,it is necessary to ensure the real-time and certainty of time-sensitive data transmission in the industrial automation field,and at the same time to ensure the high-bandwidth IT network data transmission.The existing real-time Ethernet technology has certain limitations.In order to solve the above problems,Time Sensitive Networking(TSN)is introduced into industrial automation to ensure the real-time and deterministic transmission of time-sensitive data in industrial automation,and promote the development of industrial automation.Real-time and deterministic are important performance indicators for data transmission in industrial automation.There are a variety of time-sensitive data in the industrial automation field,and the transmission of these data has very high real-time and deterministic requirements.Due to the fusion communication of high-bandwidth data in the IT network,the transmission delay and jitter of some time-sensitive data increase.In order to reduce the transmission delay and jitter of the time-sensitive data stream in industrial automation,this thesis designs and implements a time-sensitive network synchronization scheduling algorithm based on gated shaping.The main research work is as follows:1.Aiming at the real-time requirements of data transmission in industrial automation networks,this thesis proposes a multiple priority classification(Multiple Priority Classify,MPC)scheduling algorithm,which combines the different characteristic parameters of multiple data streams to shape the priority.Provide a solution to the problem of excessive queuing delay in the aggregation and transmission of data streams with different priorities.By introducing the slot window representation method,the method reconstructs the end of the slot window of the scheduled data stream into a new endpoint sequence,and uses the new endpoint sequence as the scheduling feasible solution sequence of the unscheduled data stream to quickly achieve bandwidth Resource allocation,thereby reducing the end-to-end transmission delay and jitter of the data stream.2.Based on the proposed MPC scheduling algorithm,this thesis analyzes the time-sensitive network centralized configuration model based on CNC(Centralized Network Configuration),and designs a CNC-based time-sensitive network switch configuration scheme.The program analyzes the scheduling program generated by CNC calculation by developing a shell script program,and writes the gate control list generated by CNC into the time-sensitive network switch,and grants the configuration authority of the gate control list to realize the dispatch of the scheduling plan and the configuration of time-sensitive network switch.3.In this thesis,a time-sensitive network scheduling algorithm test verification platform is built to test the data transmission delay and jitter in the time-sensitive network.The test results show that after using the scheduling algorithm proposed in this article,the maximum transmission delay of time-sensitive data streams is reduced by 55%compared to when it is not used,and the transmission jitter of time-sensitive data streams is reduced by 95.5% compared to when it is not used.In summary,the MPC scheduling algorithm proposed in this article can reduce the maximum transmission delay and jitter of time-sensitive data,and effectively improve the real-time and certainty of data transmission.