56.6.5.6 Enhancement for Scheduled Traffic (EnST)

IEEE 802.1Qbv is a TSN standard for “Enhancements for Scheduled Traffic” and specifies “time-aware queue-draining procedures” based on “timing derived from IEEE 802.1AS”. It adds transmission gates to the priority queues which allow low-priority queues to be shut down at specific times to allow higher-priority queues immediate access to the network at specific times.

For details, see Time-sensitive Networking Support (TSN).