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NWE-IP User Guide (v5.0) Configuring the Timing Settings • 37
Configuring the Timing Settings
The NWE-IP supports the Precision Time Protocol (PTP) as defined in the IEEE 1588-2008 standard and the
SMPTE ST 2059 specification.
Configuring the PTP Settings
From the Timing tab in DashBoard, you can synchronize the NWE-IP to real-time clocks of other devices in the
same network.

There are several criteria that PTP clocks compare to determine who will be master and who will be slave (called
the Best Master Clock Algorithm, or BMCA), and they are evaluated in order: Priority1, clock class, accuracy,
scaled log variance, Priority2, clock ID (similar to the MAC address). Practically, Priority1 is the only setting
configured on all clocks to control the outcome of the Grandmaster election. If Priority1s are equal, the next
criterion is evaluated (clock class) and the criteria are evaluated in succession until a Grandmaster is determined.
To update the PTP settings for the NWE-IP
1. Display the NWE-IP interfaces in DashBoard as outlined in “ To display the NWE-IP interfaces in
DashBoard ” on page 29.
2. Select the Timing tab.
 The Slave Only box is selected and cannot be edited.
3. Use the Profile menu to specify the standard/specification used for PTP.
4. Use the Domain field to specify the sub-domain the PTP clock is assigned to.
 There can be multiple PTP domains operating concurrently within a network. The domain is a field in all PTP
message headers. Messaging between entities are segregated by domain (e.g. The NWE-IP is an endpoint
configured for domain 128 and ignores messages from a neighboring clock configured for domain 127).
5. Use the Sync Interval field to specify the number of seconds at which synchronization messages are sent from
the master clock to the specified NET port on the NWE-IP.
6. Use the Announce Interval field to specify the rate of announce messages that the specified NET port on the
NWE-IP requests from the master clock during a Unicast session.
7. Use the Announce Receipt Timeout field to specify the number of seconds the specified NET port on the
NWE-IP waits for an announce interval message before timing out.
8. Click
Apply Changes
to save the new settings.