# Apple
regexp:^time(.euro)?.apple.com$

# Facebook
regexp:^time([1-5])?\.facebook\.com$

# Google
regexp:^time([1-4])?.google.com$

# NIST: https://tf.nist.gov/tf-cgi/servers.cgi
regexp:^((((ut1-wwv)|(ntp\-(b|d|wwv))|(time(\-(([a-e]\-(g|b))|([a-e]\-wwv)))?))\.nist\.gov)|((ntp-c|ut1-time)|(utcnist(2|3)?))\.colorado\.edu)$

# NTP-servers: https://ntp-servers.net/servers.html
regexp:^ntp[0-7]\.ntp-servers\.net$

clock.isc.org
ntp.fiord.ru
ntp.nat.ms
ntp.nic.cz
ntp.ripe.net
ntp.se
ntp.ufe.cz
pool.ntp.org
time.cloudflare.com
time.nrc.ca
time.windows.com

include:category-ntp-cn
include:category-ntp-jp