[time-nuts] Legal Time dissemination

[Miguel Barbosa Gonçalves]

Hi David!

On 5 June 2013 06:58, David J Taylor <david-taylor at blueyonder.co.uk> wrote:

>
> Miguel,
>
> I notice a step in the blue (ntp02) graph in:
>
>  http://www.flickr.com/photos/**miguelbarbosagoncalves/**8955346508/<http://www.flickr.com/photos/miguelbarbosagoncalves/8955346508/>
>
> and I think in the red (ntp04) graph as well.  This suggests some change
> in connectivity between your monitoring PC and both servers, so perhaps a
> network change.  Unless your stratum-1 server took a 2 millisecond step,
> which seems unlikely.
>

I believe something has happened but not on my side. The offset for ntp02
changed its sign but kept the absolute value.


> Their ntp02looks well behaved, but their ntp04 is clearly not well
> behaved, and disappointing for public service.  In my own plotting program:
>

Indeed! Very disappointing! And it is payed by my taxes!!! :-(


>  http://www.satsignal.eu/**software/net.htm#NTPplotter<http://www.satsignal.eu/software/net.htm#NTPplotter>
>
> I find it useful to be able to plot the offset versus time of day, as
> regular temperature variations tend to stand out - at least in my
> environment where the heating switches on at the same time every morning.
> For comparison on a similar time scale, you might like to look at my
> Windows LAN-synced PCs here:
>
>  http://www.satsignal.eu/mrtg/**performance_ntp.php?period=**week#windows<http://www.satsignal.eu/mrtg/performance_ntp.php?period=week#windows>
>
> so even if their servers were running Windows, they could be doing far
> better than that your graph suggests.  Could you plot offset versus time of
> day?
>

Will do that later today. I am also gathering the offset of my stratum 1 in
the same location against ntp02 and ntp04 and another set of stratum 2
servers located in an University. The first 24 hours look rather
interesting: ntp02 and these new servers are quite stable (around 1 ms
offset in absolute value) and ntp04 keeps doing crazy things.

Once I have enough data I will contact them.

Cheers,
Miguel