KSwitch D10 MMT Managed Time Sensitive Ethernet Switch - Preliminary User Guide, Rev. 0.99
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5.3.
Time Aware Shaper (TAS)
Time Aware Shaper is defined in the IEEE 802.1Qbv standard and is the ability to allow transmission from each queue
to be scheduled relative to a known global timescale.
The global time is maintained by using a specific version of Precision Time Protocol (PTP) as defined in IEEE 802.1AS-
Rev.
5.3.1.
Configuration of Parameters
The syntax for TSN TAS interface level CLI configuration command is:
tsn tas always-guard-band
no tsn tas always-guard-band
Where:
always-guard-band:
Guard band is implemented for any queue to scheduled queues
transition.
no always-guard-band: Guard band is implemented for non-scheduled queues to scheduled
queues transition.
The syntax for TSN TAS interface level CLI configuration command is:
tsn tas base-time seconds <seconds> nanoseconds <nanoseconds>
tsn tas config-change
tsn tas control-list index <index> gate-state queue <queue> { open | closed }
time-interval <interval> [ operation { set | set-hold | set-release } ]
tsn tas control-list-length <length>
tsn tas cycle-time <time> { ms | us | ns }
tsn tas cycle-time-extension <extension>
tsn tas gate-enabled
tsn tas gate-states queue <queue> { open | closed }
tsn tas max-sdu queue <queue> <sdu>
The following parameters are defined in IEEE802.1Q: ieee802.1STMib
base-time
Admin Base Time.
config-change
Start a configuration change
control-list
Admin Control List
control-list-length
Admin Control List Length
cycle-time
Admin Cycle Time
cycle-time-extension
Admin Cycle Time Extension
gate-enabled
Enabled state of Time Aware Shaping
gate-states
Initial gate state for each queue
max-sdu
Queue Max SDU configuration
queue
Traffic class. 0-7.
Index
Index of Gate Control Entry
gate-state
Admin Gate State
time-interval
Time Interval in Nanoseconds
operation
set | set-hold | set-release
5.3.2.
Configuring Examples
CLI commands example:
! Create and start a Time Aware Shaper schedule on port 1.
! The schedule contains three gate control entries:
! 0: Open queue 7 and close all other queues for 20 milliseconds
! 1: Open queue 5-6 and close all other queues for 30 milliseconds
! 2: Open queue 0-4 and close all other queues for 50 milliseconds
! The schedule is repeated every 110 milliseconds
! TAS is scheduled to start at seconds 4300 nanoseconds 500