A while ago we (SIDN Labs) published a paper about the NTP pool.
It can be found here:
(under ‘Diving into the NTP pool’).
- Most clients are provided with fewer than 200 NTP servers, despite the fact that ~4.6k servers are listed on the NTP pool.
- 10% of the clients see up to 12 IPv4 and 5 IPv6 NTP servers.
- Most countries (60%) are served by 10 time providers only.
- 13 countries are served by a single IPv4 time provider – which includes Israel, Pakistan, and Nigeria, while 42 countries are served by (the same) single IPv6 provider.
- We found 9 IPv4 NTP servers on the NTP pool that deploy BGP anycast.
No shocking conclusions per se, but it might nevertheless be worth reading for those who are interested.