Asynchronous Time-Aware Shaper for Time-Sensitive Networking

Abstract

The Time Sensitive Networking task group of IEEE 802.1 has developed a number of enhancements to the priority queueing architecture used by Ethernet. Perhaps the most notable one is the Time-Aware Shaper, which can perfectly isolate priority classes in time with periodically scheduled traffic gates. It requires near-perfect clock synchronization across the entire network, though, and a central network controller to calculate the timings for the traffic gates. As a cheaper alternative, we developed the Asynchronous Time-Aware Shaper that needs no clock synchronization, or a central controller. It uses local processes at each switch port to track the high priority streams, predict the arrival times of their next frames, and control the traffic gates such that the low priority streams are not interfering.