Clocking Settings

In order to enable synchronous clocking across domains that span multiple subnets, devices must be assigned as unicast clocks for each subnet in the domain. This can be done automatically, or manually.

Unicast clocks distribute clocking between subnets via unicast PTP. They can act as a unicast master or a unicast slave, depending on their proximity to the grand master clock. For example, a unicast clock in the same subnet as the grand master clock for the domain has the role of unicast master, transmitting PTP to a unicast slave in another subnet - which then distributes multicast PTP for the other devices in its subnet.

See also: Synchronous Clocking

A unicast clock will often (but not always) also act as the multicast clock master for its own subnet.

If all PTP unicast clocks for a domain are removed from the network, powered down, or unenrolled from the domain, the subnet will lose its clock connection to other subnets, and audio between subnets may begin to glitch until a new unicast clock is assigned. The DDM dashboard will provide a notification in this event.

Note:  Clocking configuration is only required for domains that span two or more subnets.

Note:  Legacy Ultimo devices cannot function as unicast clocks, but Ultimo X devices can. To determine if a device is legacy Ultimo or Ultimo X: In Dante Controller, open the Device View > Status tab for the device, and check the Model type in the Dante Information panel. Legacy Ultimo devices are listed as 'Ultimo' or 'Ultimo4', and Ultimo X devices are listed as 'UltimoX' or 'UltimoX4'.

Auto-configure

The Auto-configure function assigns one device in each subnet to act as the active unicast clock, and also where possible a secondary unicast clock to act as backup if the active unicast clock is disconnected, powered off or unenrolled.

Auto-configure is applied at the point of configuration. The DDM will not independently reconfigure unicast PTP in the event of a device failure.

To configure clocking for a domain automatically:

  1. In the Domains menu, select the domain.
  2. In the Settings section of the Domain Details panel, click Auto-Configure.

To see or change which devices have been assigned as unicast clocks, click Advanced Settings.