Magnus Danielson wrote: >From: "Rob Kimberley" <[EMAIL PROTECTED]> >Subject: Re: [time-nuts] NTP stratum 0 >Date: Sat, 14 Jan 2006 18:48:16 -0000 >Message-ID: ><!&!AAAAAAAAAAAYAAAAAAAAAOYAZyOzV8ERq+LmT45ypI7CgAAAEAAAAAzy/[EMAIL PROTECTED]> > > > >>The Stratum numbers in the Telecom Sync industry and those used in NTP >>hierarchy are different beasts. >> >> > >I agree, they are completely different beasts. > > > >>In Telecom Sync, Stratum 1, 2, 3 et al are internationally defined levels of >>frequency accuracy. >> >> > >Um, no. They are nationally specified in the USA. You find them in ANSI T1.101. >For their international variants you have to go to ETSI EN 300 462 series, as >well as the ITU-T Rec. G.810 to G.813. Neither the ETSI or ITU-T standards uses >Stratum indications, instead they use designations such as PRC, SSU and SEC. > > > Yes the T1.101 is a USA standard, but when it was finalized there was international contributions and every attempt was made to harmonize the international standards and the USA T1.101. I was active in the T1X3 meetings.
Bill K7NOM >>In NTP Stratum 1 merely means the top of the hierarchical pyramid with >>Stratum 2, 3 etc below it. >> >> > >Indeed. It is really just a reference chain length from whatever the reference >is, which may anything form a Ceasium-beam with coordinated time to an >undiciplined XO. > > > >>Stratum 0 has been used in discussions I have seen from people at Datum >>and TrueTime to represent a GPS/NTP reference, but realistically I believe >>that it should be labelled as Stratum 1. >> >> > >Indeed. > > > >>Would humbly suggest you take a look at www.ntp.org for more information. >> >> > >Also, the references from earlier this thread adds up. The RFC 1305 is as such >a very interesting article. > >Cheers, >Magnus > >_______________________________________________ >time-nuts mailing list >[email protected] >https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > > > > > _______________________________________________ time-nuts mailing list [email protected] https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts
