Design of coordinated transmission mechanism of heterogeneoustime-sensitive data flow for industrial internet

Abstract

<p indent="0mm">Industrial internet needs to realize the integration of IT (information technology) and OT (operation technology). The construction of the field-level industrial network is key to truly realizing seamless access of production line data from OT to IT and the intelligent operation and maintenance of the production line from IT to OT. For OT, the data in the industrial system is highly time-sensitive, and the deterministic behavior of perceived data and control instructions in time is the foundation for reliable and stable industrial system operation. However, the industrial field is plagued by problems such as heterogeneous perceived data, incompatible protocols, and varying transmission requirements, which pose significant challenges to the deterministic transmission of heterogeneous time-sensitive flow. One feasible solution to this problem is to design a unified time-aware gating mechanism with low delay and jitter, allowing precise control of data flow transmission behavior; this is one of the key technologies in the time-sensitive networking (TSN) standard. This paper mainly studies the coordinated transmission of heterogeneous time-sensitive flow in multi-hop TSN networks. First, heterogeneous time-sensitive traffic is modeled into two categories: periodic time-sensitive (PTS) flow and sporadic time-sensitive (STS) flow. Then, the schedulability of the PTS flow set and the design method of the gate control lists are analyzed, the sufficient and necessary conditions of schedulability are defined, and a schedulability discriminant algorithm is designed to determine the schedulability of any decision set. Then, a coordinated transmission framework of heterogeneous time-sensitive flow is proposed, followed by the construction of the constraint set of heterogeneous data scheduling. This paper employs the design method of no-wait slot scheduling and constructs the heterogeneous time-sensitive flow scheduling problem with the optimization goal of minimizing the maximum slot occupation in the scheduling unit to achieve the minimum end-to-end deterministic delay of PTS flow and to reduce the impact of PTS scheduling mechanism on STS flow transmission as much as possible. Then, a uniform arrangement and filling (UAF) algorithm is developed to minimize slot occupation of scheduling units by uniformly arranging the flow of the same period and filling the idle time slots generated during pre-period scheduling. Finally, simulation and experiment results corroborate the effectiveness of the two kinds of heterogeneous time-sensitive flow coordinated transmission framework and the efficiency of the UAF scheduling algorithm based on ensuring the same scheduling performance.