Research On Key Technologies Of Tsn Traffic Scheduling Based On Integer Linear Programming

Under the background of Industry 4.0,the importance of the Industrial Internet is becoming increasingly prominent.Traditional industrial Internet mainly focuses on the control process.However,there are compatibility problems,such as fieldbus communication protocol standards and physical interfaces,which significantly limits the interconnection of the industrial Internet.Industrial Ethernet(Industrial Ethernet)technology follows TCP/IP architecture,has the advantages of a simple interface,open protocol,and flexible interworking,and has gradually become the mainstream technology of industrial control networks.The control message needs to be transmitted in a limited time in the industrial control process.That is,time delay and delay jitter are limited.Compared with general Ethernet,just-in-time deterministic transmission is one of the main characteristics of industrial Ethernet.In 2012,Time-Triggered Ethernet(TTEthernet)was triggered by the IEEE AVB Task Force.The IEEE 802.1 Time Sensitive Networking(TSN)Working Group on the real-time performance of industrial Internet has been established.TSN provides a time-sensitive mechanism for Ethernet data Link layer protocol,which ensures the time certainty of Ethernet data communication and preserves communication compatibility between networks using different protocols.In the natural industrial network environment,services and traffic types are diversified,so how to design scheduling algorithms for different types of traffic is a hot research direction.The research in this thesis mainly includes the following aspects:(1)A new industrial network architecture of a Time-sensitive Software-defined network(TSSDN)is proposed for different industrial network environments and traffic characteristics.First,different types of TT traffic in industrial networks are classified according to delay requirements and frame loss tolerance,namely,time-sensitive services with high delay requirements and control services with low delay requirements.On this basis,traffic scheduling algorithms for different services are proposed,and the performance of the proposed algorithms is analyzed by simulation.(2)Aiming at the problems of new traffic joining and network topology changes caused by dynamic applications in industrial production environments,this paper proposes a network update scheduling algorithm with a complete separation of old and new schedules.The algorithm is constrained by traffic conflicts in old and new networks,solves the problem of traffic conflicts that may occur while updating network scheduling plans,and compares them with traditional schemes in the two network topologies.Experimental results show that the proposed algorithm is superior to traditional methods regarding network resource utilization and update time.(3)Based on the open-source network framework,this paper constructs a new TSN network test environment based on OMNeT++,which realizes the design and construction of network nodes and topology.Compared with the traditional network test environment,this network test environment has new processing logic at the switch level.The network test environment is used to simulate and test the traffic jitter of the scheduling algorithm and verify the effectiveness of the above algorithm.