nanog mailing list archives
Re: NIST NTP servers
From: Mel Beckman <mel () beckman org>
Date: Thu, 12 May 2016 18:09:52 +0000
The WWV signal is still accurate within a few milliseconds. Light is fast. Really fast. -mel
On May 12, 2016, at 10:19 AM, Jean-Francois Mezei <jfmezei_nanog () vaxination ca> wrote: On 2016-05-11 10:30, Mel Beckman wrote:Read deeper into the thread and you'll find where I sourced inexpensive RF-based NTP servers using CDMA, GSM, and even WWV.For shortwave, you would need to calculate propagation delay between transmitter and receiver. (does signal reach via line of sight, bounce against ionosphere ?). Since CDMA is dead outside the USA and drying in USA, I wouldn't rely on that. If GSM towers rely on a GPS receiver on the tower and those towers are near enough to your location (< 30km), then chances are that blocked GPS signals at your location would also jam the signals at the GSM antenna. And if you are setup to be totally autonomous in case of power failures, you need to know whether the GSM antenna you are relying on is also on permanent power backup or only has autonomy of a few hours.
Current thread:
- Re: NIST NTP servers, (continued)
- Re: NIST NTP servers Gary E. Miller (May 10)
- Re: NIST NTP servers Mel Beckman (May 10)
- Re: NIST NTP servers Leo Bicknell (May 11)
- Re: NIST NTP servers Josh Reynolds (May 11)
- Re: NIST NTP servers Mel Beckman (May 11)
- Re: NIST NTP servers Jay R. Ashworth (May 11)
- Re: NIST NTP servers Valdis . Kletnieks (May 11)
- Re: NIST NTP servers Mel Beckman (May 11)
- Re: NIST NTP servers Eric Kuhnke (May 11)
- Re: NIST NTP servers Jean-Francois Mezei (May 12)
- Re: NIST NTP servers Mel Beckman (May 12)
- Re: NIST NTP servers Leo Bicknell (May 11)
- Re: NIST NTP servers Brandon Vincent (May 11)
- Re: NIST NTP servers Jon Meek (May 11)
- Re: NIST NTP servers Josh Reynolds (May 11)
- Re: NIST NTP servers Lamar Owen (May 13)
- Re: NIST NTP servers Mel Beckman (May 13)
- Re: NIST NTP servers Lamar Owen (May 13)
- Re: NIST NTP servers Mel Beckman (May 13)
- Re: NIST NTP servers Mel Beckman (May 13)
- Re: NIST NTP servers Lamar Owen (May 14)