pc wrote:
At risk of stirring up a hornets' nest:
The RFC unequivocally states that "A primary server is
synchronized to a reference clock directly traceable to
UTC."
IMO, that is not a necessary condition. If I have a
hierarchy of NTP servers and clients with no external
connection to the Internet and I feed in Northern
Bongosooziland Spring Time (NBST) at the top of the
hierarchy, NTP will propagate that time throughout the
hierarchy. The only condition is that NBST must tick at a
rate of approximately 1 second per UTC second, otherwise the
finely-tuned FLL and PLL will not perform optimally.
Many users of this list have a requirement to synchronize a
number of machines within some user-defined limit, but they
don't care if they are all offset from UTC by a few minutes.
Time islands would seem to be a common use-case, and it's my
opinion that the RFC's assertion that genuine NTP networks
must be based on UTC is an unnecessary restriction. I
suggest that the RFC should mention that UTC-based NTP is
probably the most valuable use-case, and is the only form of
NTP that should be allowed on the Internet, whilst admitting
the existence of time islands.
Paul
There may be people who cannot use UTC or who simply do not care what
time it really is as long as all their clocks agree, but should we care
what they want or what they believe???
NTP is about time traceable to UTC and accurate to the extent permitted
by the medium of transmission.
I'm not going to send assassins to deal with those who disagree. . . .
It may also be worth noting that systems following an ultra
accurate/stable source seem to agree with each other more closely than
if the source is afflicted with random phase noise.
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