[ntp:questions] Number of Stratum 1 & Stratum 2 Peers

Martin Burnicki martin.burnicki at meinberg.de
Wed Dec 17 13:31:13 UTC 2014


Rob wrote:
> Martin Burnicki <martin.burnicki at meinberg.de> wrote:
>> IMO the GPS system designers have made quite a number of wise decisions,
>> e.g. letting the GPS time simply increase monotonically, which is, from
>> a technical/usage point of view, similar to TAI.
>
> That decision was wise.  The decision to express date in weeks and put
> it in a 10-bit field was not so wise.  Oh well.

Only the 10 bit field wasn't. However, for a pure navigation system this 
doesn't matter at all. Only if you need the current legal date and time 
the epoch matters.

With regard to this, using only a truncated 8 bit week number to specify 
the week of a leap second event is also not the best solution.

It can only handle a +/-127 week interval, and expanding this to a full 
date is ambiguous if there was no leap second event for a period 
exceeding this interval.

Martin



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