CenturyLink

Sun Dec 30 18:04:56 UTC 2018

Regulatory.

If we were to lose the GPS signal (antenna failure, etc...) then our stratum 1 time sources wouldn't drift as much and as quickly. For telco and general usage, the cost may not be worthwhile, but when you have auditors looking over your shoulder....

----
Matthew Huff             | 1 Manhattanville Rd 
Director of Operations   | Purchase, NY 10577
OTA Management LLC       | Phone: 914-460-4039

-----Original Message-----
From: Saku Ytti [mailto:saku at ytti.fi] 
Sent: Sunday, December 30, 2018 12:30 PM
To: Matthew Huff <mhuff at ox.com>
Cc: Shawn L <shawnl at up.net>; nanog at nanog.org
Subject: Re: CenturyLink

Hey Matthew,

> We use an older model of https://www.microsemi.com/product-directory/enterprise-network-time-servers/4117-syncserver-s600 with rubidium oscillator. Not cheap, but hardened and extremely accurate.

Out of interest why rubidium? For short term stability oscillator choice isn't much of a matter for free running even rubidium will be off good +-1us per day or +-30us per week. I've always wondered what niche rubidium covers that isn't handled by much cheaper crystal ovens or actually precise oscillators.

--
  ++ytti