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<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D">We use an older model of
<a href="https://www.microsemi.com/product-directory/enterprise-network-time-servers/4117-syncserver-s600">
https://www.microsemi.com/product-directory/enterprise-network-time-servers/4117-syncserver-s600</a> with rubidium oscillator. Not cheap, but hardened and extremely accurate.
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";color:#1F497D">----<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";color:#1F497D">Matthew Huff | 1 Manhattanville Rd
<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";color:#1F497D">Director of Operations | Purchase, NY 10577<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:11.0pt;font-family:"Courier New";color:#1F497D">OTA Management LLC | Phone: 914-460-4039<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:14.0pt;font-family:"Calibri",sans-serif;color:#1F497D"><o:p> </o:p></span></p>
<p class="MsoNormal"><b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif">From:</span></b><span style="font-size:11.0pt;font-family:"Calibri",sans-serif"> Shawn L [mailto:shawnl@up.net]
<br>
<b>Sent:</b> Sunday, December 30, 2018 9:40 AM<br>
<b>To:</b> nanog@nanog.org<br>
<b>Cc:</b> Matthew Huff <mhuff@ox.com>; list@satchell.net<br>
<b>Subject:</b> Re: CenturyLink<o:p></o:p></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p style="margin:0in;margin-bottom:.0001pt"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">Speaking of GPS-enabled NTP appliances, etc. wondering what hardware people are using for this.<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;overflow-wrap: break-word"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;overflow-wrap: break-word"><span style="font-size:10.0pt;font-family:"Arial",sans-serif">thanks<o:p></o:p></span></p>
<p style="margin:0in;margin-bottom:.0001pt;overflow-wrap: break-word"><span style="font-size:10.0pt;font-family:"Arial",sans-serif"> <o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Arial",sans-serif"><br>
-----Original Message-----<br>
From: "Raymond Burkholder" <<a href="mailto:ray@oneunified.net">ray@oneunified.net</a>><br>
Sent: Saturday, December 29, 2018 12:01pm<br>
To: "Matthew Huff" <<a href="mailto:mhuff@ox.com">mhuff@ox.com</a>>, "<a href="mailto:list@satchell.net">list@satchell.net</a>" <<a href="mailto:list@satchell.net">list@satchell.net</a>>, "<a href="mailto:nanog@nanog.org">nanog@nanog.org</a>" <<a href="mailto:nanog@nanog.org">nanog@nanog.org</a>><br>
Subject: Re: CenturyLink<o:p></o:p></span></p>
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<span style="font-size:10.0pt;font-family:"Arial",sans-serif">On 2018-12-29 7:51 a.m., Matthew Huff wrote:<br>
> We have two stratum-1 servers synced with GPS and a PTP feed from a provider that also provides PTP to market data systems, but we still have to monitor drift between system time and NIST time. Don't ask for the logic behind it, it's a regulation, not a technical
requirement.<br>
><br>
On one occasion, due to bad firmware or a configuration issue, I have <br>
seen GPS stratum 1 diverge from NTP. It was somewhat eye brow raising <br>
to the company. My NTP monitored servers were shown to be diverging <br>
their GPS/NTP, but after looking at twice or thrice, it was the other <br>
way around.<o:p></o:p></span></p>
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