NTP
From:
https://github.com/espressif/arduino-esp32/blob/master/cores/esp32/esp32-hal-time.c
NTPclient
ESP NTP Client Ref
Udp.h
NTPClient.cpp
NTPClient.h
esp32HalTime.c
Examples
Advanced
Basic
IsTimeSet
time Client
timClt 2
NTP Stuff
IPv6–PublicPolicy
BigBadInternet
MITMandRoutingSecurity
DNS
NetworkTimeProto
Dotless
Policy
How-Does-NTP-Work
Routing
Security
IPAddrsAndTraceback
Struct NTP Packet
IP-Addrs
ValuingIPAddrs
IPv6
Who Uses Google's DNS
MKR UDP NTP Client
Connect to NTP Server
DateTime Ref
DateTime.cpp
BGPin2013
TimeInfo Strcture