Safran SecureSync 2400 - The NTP Stratum Model; Configuring NTP Stratum 1 Operation

2.15.7.1 The NTP Stratum Model
The NTP Stratum model is a representation of the hierarchy of time servers in an
NTP network, where the Stratum level (0-15) indicates the device's distance to
the reference clock.
Stratum0 means a device is directly connected to e.g., a GPS antenna.
Stratum0 devices cannot distribute time over a network directly, though, hence
they must be linked to a Stratum1 time server that will distribute time to
Stratum2 servers or clients, and so on. The higher the Stratum number, the more
the timing accuracy and stability degrades.
The NTP protocol does not allow clients to accept time from a Stratum 15 device,
hence Stratum 15 is the lowest NTP Stratum.
A group of NTP servers at the same Stratum level (Stratum 2, for example) are
considered NTP Peers to each other. NTP Servers at a higher Stratum level, on
the other hand, are referred to as NTP Servers.
Note: Internet Time Servers should be configured as NTP Servers
and not as NTP Peers.
If SecureSync has no valid Timing System Reference, NTP Server or NTP Peers,
the NTP Stratum value is automatically downgraded to Stratum 15. This ensures
that its NTP clients will no longer use this SecureSync unit as a time reference.
2.15.7.2 Configuring "NTP Stratum 1" Operation
When the Timing System references of your SecureSync are normally available
(rather than being unavailable most of the time e.g., in areas with poor GNSS
reception), it is advisable to use the System Time as a reference to NTP, since this
provides NTP with the most accurate references. This mode is called Stratum 1
operation, since SecureSync operates as a Stratum1 NTP server.
To configure Stratum 1 operation for SecureSync:
1.
Navigate to MANAGEMENT > NETWORK: NTP Setup:
2.
Click the GEAR icon in the NTP Services panel.
3.
The Edit NTP Services window will display. Click the Stratum 1 tab.
4. Check all of the three options:
Enable Stratum 1 Operation
Checking this option will cause the NTP Service to use the System
Time provided by the Timing System input.
2.15 Configure NTP
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