Research On Multipath Routing And Scheduling For Time-triggered Flow In Time-sensitive Network

With the improvement of the digitization and intelligence of industrial networks,the demand for high reliability of real-time data transmission has become more and more urgent.As a brand-new technology,time-sensitive network(TSN)provides real-time transmissions for various types of flows through standardization,which makes up for the shortcomings that standard Ethernet architecture is difficult to provide low-latency communication.In TSN,time-triggered(TT)flow is in high-priority,which normally carries critical control data in industrial applications.In order to ensure the reliability of transmission for TT flows,redundancy is usually used to achieve fault tolerance of the network,but the excessive loads caused by redundancy will significantly affect the schedulability of TT flows.Therefore,how to balance the schedulability and reliability of data transmission has become an urgent problem in TSN researches.This paper firstly addresses the shortcomings of existing TSN routing methods in industrial scenarios.Based on the framework of switched Ethernet,this paper analyzes the factors affecting routing reliability and schedulability,and proposes two evaluation techniques: A probability model that measures routing reliability and a cost function that measures the possibility of timeslot overlapping on shared links.Secondly,based on the above techniques,this paper designs a reliability-aware multipath routing method.This method screens the routing solutions based on the probability model,and uses Antlion Optimizer to minimize the cost function,finding a routing solution with higher schedulability in the search space.Thereby the reliability of real-time data transmission is co-optimized in TSN containing unreliable links.Finally,this paper constructs the related scheduling constraints based on the TSN forwarding mechanism,and uses integer linear programming to solve the scheduling problem.In order to verify the effectiveness of the proposed method,this paper evaluates the existing benchmark routing method and the proposed method in terms of reliability and schedulability.In topologies with different connectivities and scales,the influence of unreliable links and the number of loads on routing reliability and schedulability are studied separately.Experimental results prove that compared with the existing methods,the routing method proposed in this paper can increase the reliability by 1.8% on average;while ensuring the reliability of transmission,the schedulability is increased by 10% on average.In a larger-scale,higher-connectivity TSN with more loads,reliability and schedulability have improved more significantly,at 5% and 17%,respectively.