68
Scenario3:re-establishmentoftheprimarysource
> Freerun on product start-up
> Synchronisation with the primary source (e.g. GPS)
> Loss of synchronisation from the primary source
>
> (e.g. NTP)
> Switch to the primary synchronisation source.
Scenario4:synchronisationwiththesecondarysourcewherenoprimarysourceispresent
> Freerun on product start-up
> Timeout
1
for synchronisation with the primary source (e.g. GPS)
> Synchronisation with the secondary source (e.g. NTP)
Scenario5:nosynchronisationsource
> Freerun on product start-up
> Timeout for synchronisation with the primary source (e.g. GPS)
> Timeout for synchronisation with the secondary source (e.g. NTP)
> No synchronisation: switch to freerun
Change
of source
Synchronised
(primary)
Statuses:
Notifications: Synchronised
Change
of source
Holdover
Freerun
Synchronised
(primary)
Synchronised
(secondary)
Holdover
1
Thetimeoutdurationdependsonthesynchronisationsource:
> BodetGPS:5minutes
> NTP:15minutes
Statuses:
Notifications: Synchronised
Freerun
Time. 1
st
synchro.
Synchronised
(secondary)
Time. 2
nd
synchro.
Freerun
Statuses:
Notifications:
Loss of synchronisation then
switch to freerun
Freerun
Time. 1
st
synchro.