Yes, there is a risk that systems will drift due to accumulated leap seconds 
without updates.We worked throuugh the details... 
http://lloydwood.users.sourceforge.net/Personal/L.Wood/publications/wood-ieee-aerospace-2009-bundle-problems.pdf
 
but keeping time accurately and continuously (temperature extremes causing 
drift, power loss) is likely more of an issue in many use cases.
The background assumption here is the NASA interplanetary internet use case 
(and first RG before DTNRG), where a spacecraft without a clock is useless, the 
clock is a critical component and sync'd with updates continuously somehow, all 
hail the clock.
DTN doesn't scale beyond that to other use cases that well.

Lloyd [email protected]



On Friday, November 8, 2019, 11:35 pm, Stewart Bryant 
<[email protected]> wrote:


Hi Magnus

I will address the other points in a later email, but on this I am concerned 
that WG have a misunderstanding of the timebase they are using. UNIX/POSIX time 
does have leap seconds it just handles them silently so you will get double 
increments. However since my follow-up note yesterday, I was wondering how the 
remote remote system knew to add a leap second in order to keep in track with 
the local system? Isn’t there a risk that the two systems will drift apart as 
leap seconds are added locally? Also there is the rollover problem to worry 
about.

I think the section needs to go to a specialist group for review such as 
TicToc/NTP to verify that it works exactly as the WG expect.



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