Comment by mmagin

Article doesn't bother to mention that there are completely different projects which implement NTP servers with varying levels of functionality (openntpd, chrony, ntpsec, ntimed). And while the pool.ntp.org system is a nice scheme, it's hardly a global necessity. You can fairly easily get a stratum 1 server going on your own infrastructure. IMHO, too much of NTP relies on GPS, but that's a separate matter.