Deterministic Transmission for the Asynchronous Converged Networks of Profinet and TSN

With the rapid growth of Industry 4.0, time-sensitive networking (TSN) has emerged as the new infrastructure for future industrial Internet of Things (IoT) communication. Ensuring the compatibility between TSN and legacy networks is inevitable. The ideal compatibility is to achieve deterministic interconnection and interoperability without changes in hardware and communication protocols, in other words, only using standard devices with software management. This paper targets the ideal compatibility of TSN and Profinet Isochronous Real Time (IRT). First, we propose an inter-domain Multiple Transmission Opportunity Mechanism (MTOM) to enable the asynchronous converged network of TSN and Profinet. The mechanism reserves multiple transmission time slots for cross-domain data flows to reduce their end-to-end delay and jitter. Second, we formulate an asynchronous scheduling model (ASM) based on MTOM to coschedule flows in inter-and-intra domains. Finally, a case study is performed on a typical industrial network. The experiment results demonstrate that the proposed MTOM can only use standard devices to achieve deterministic transmission of Profinet and TSN converged networks. Compared with previous asynchronous converged networks, the delay and jitter are reduced by 86% and 80% on average, respectively.