TCXO and OCXO (was: [ntp:questions] Problem with NTP multicast server configuration)

TCXO and OCXO (was: [ntp:questions] Problem with NTP multicast server configuration)

Post by David J Ta » Mon, 17 Jan 2005 18:48:54



[]

Just an aside on terminology. You have the acronyms wrong, it's TCXO and
OCXO - the X is crystal, an abbreviation of Xtal!

TCXO: Temperature Compensated Crystal Oscillator

OCXO: Oven Controlled Crystal Oscillator

e.g.
http://www.yqcomputer.com/
http://www.yqcomputer.com/

and many more, of course.

Cheers,
David
 
 
 

1. [ntp:questions] linux kernel 2.6.3, ntp-4.1.2 ok, ntp-4.2.0 won't work

2. [ntp:questions] NTP does not sync when using pool.ntp.org


You'd have to make sure that the order of listing in each pool is
totally different from the other two -- pseudo-random number
generators may be helpful here. Of course, you can't guarantee that
the secondaries are going to serve out those records in the same
order as the master. ;-(


For the larger pools (i.e., pool.ntp.org), this would certainly
be true. For the smaller pools (i.e., ones with only a handful of
addresses), it would be far too easy for them to get in sync.

For this reason, it might actually be best to have country-level
pools be CNAME aliases to region-level pools (e.g.,
europe.pool.ntp.org, na.pool.ntp.org, etc...), unless there are
enough servers within a single country to ensure a reasonably low
probability of getting in sync (i.e., at least ten or more).

If there aren't enough region-level servers, then they could be
further CNAME aliases to hemisphere-level (or other higher-level)
pools.


I have specialized in the DNS for a number of years, and I was a
technical reviewer of 2nd edition of the O'Reilly book _DNS and
BIND_. I'm working on a variety of ideas to try to help make this
concept work better.

--
Brad Knowles, < XXXX@XXXXX.COM >

"They that can give up essential liberty to obtain a little temporary
safety deserve neither liberty nor safety."
-Benjamin Franklin, Historical Review of Pennsylvania.

GCS/IT d+(-) s:+(++)>: a C++(+++)$ UMBSHI++++$ P+>++ L+ !E-(---) W+++(--) N+
!w--- O- M++ V PS++(+++) PE- Y+(++) PGP>+++ t+(+++) 5++(+++) X++(+++) R+(+++)
tv+(+++) b+(++++) DI+(++++) D+(++) G+(++++) e++>++++ h--- r---(+++)* z(+++)

3. [ntp:questions] Lists of public NTP servers

4. [ntp:questions] ntp client: keep all servers at startup

5. [ntp:questions] Unable to get time from NTP server

6. [ntp:questions] ntp 4.2 crash on specific servers

7. [ntp:questions] Unable to get time from NTP server

8. [ntp:questions] NTP Time Server for LAN: Broadcasting or Not?

9. [ntp:questions] Announcement: Australian NTP servers

10. [ntp:questions] ntp client: keep all servers at startup

11. [ntp:questions] NTP Time Server for LAN: Broadcasting or Not?

12. [ntp:questions] different times from same ntp server

13. [ntp:questions] ntp server behind ADSL alcatel speedtouch 510 firewall not responding.

14. [ntp:questions] Lists of public NTP servers

15. [ntp:questions] What's different about these (S)NTP servers?