Optimization of Bandwidth Utilization and Gate Control List Configuration in 802.1Qbv Networks

Abstract

The IEEE 802.1 Time-Sensitive Networking (TSN) Task Group has been developing various standards since 2012 to provide deterministic and time-critical services through IEEE 802 networks. The Time-Aware Shaper (TAS) is a key component in TSN that was introduced to enable precise forwarding and shaping of time-sensitive network traffic. It allows configuring exclusive transmission slots for selected traffic classes. To achieve the best benefit from the TAS, numerous scheduling algorithms have been presented to find schedules for the transmission of time-critical network streams optimizing the stream end-to-end transmission times in TAS-based networks. However, most existing works do not address how the scheduling of critical network traffic affects the necessary number of critical transmission slots that is limited in hardware and the resulting bandwidth utilization for other traffic classes. In this paper, we have investigated how a selected set of heuristic and meta-heuristic algorithms for scheduling critical network streams in TAS-based networks affects the utilization of network resources, and how the configuration of TAS can be improved using a compression algorithm. Therefore, we make use of existing algorithms and propose alternatives that have an influence on input data ordering, scheduling procedures, and the TAS configuration. The evaluation showed that some of our proposed modifications can improve bandwidth utilization and reduce the number of transmission slots for critical traffic significantly. Further on, the compression algorithm can bring a remarkable improvement in isolated cases.

Keywords

• TSN
• real-time
• scheduling
• ethernet networks