NTP hierarchy
Jeff Kronlage's CCIE Study Blog: NTP
How to set up NTP server in CentOS
NTP Server – Stratum Levels Explained | NTP Server
NTP Stratum | ESE
Network Time Protocol - Wikipedia
87Rb Stratum 1 NTP Server – HARDWARE – Delta²
What NTP stratum level is a server that is connected directly to an authoritative time source?
What is Network Time Protocol (NTP)? - Definition from WhatIs.com
What is a Stratum 1 Time Server? - NTP | TimeTools Ltd
A diagram showing the relationship between the various level of NTP... | Download Scientific Diagram
Time reference for your network - (NTP - The Network Time Protocol)
Introducing time.cloudflare.com
NTP Server
GPS Network Time Synchronization — Masterclock, Inc.
Network Time Protocol - Wikipedia
What is Windows's time server synchronisation precision? (and does it compensate the ping time?) - Super User
NTP: The Network Time Protocol
Why does NTP Exist? — Developer Musings
What Time Server Do I Need For My Business? - Galleon Systems
Network Time Protocol (NTP). Network Time Protocol (NTP) is a… | by lewis malim | Medium
time - Set local stratum 0 NTP server without internet - Arduino Stack Exchange
Seven best practices to keep your NTP resilient – BlueCat Networks
