[citation][nom]drut1234[/nom]"what about the clocks we have mounted on the wall "They have been making clocks that get their time sync from an AM signal for decades.[/citation]
RIGHT you are!!! Just google: atomic wall clock
These "atomic clocks" however they are not atomic but sync with the many actual atomic clocks around the world that are sending out radio signals that are picked up by an appropriate receiver. http/en.wikipedia.org/wiki/Atomic_clock#Radio_clocks
So begs to ask, why an Ethernet wall clock? It's not a simplier, less expensive, less power, or even more elegant mouse trap than the radio clock. Even if they come out with a wireless ver as in WiFi or what ever.... Isn't that just a me too (ie: radio vs WiFi) that will most likely use more power, etc. So why??? There are also GPS clock devices that can be deployed for even more accuracy than the radio "better brands of radio clocks are normally accurate to the second" but GPS clocks can be even more accurate. SO only if mounting an radio or GPS antenna (even a remote antenna) is not possible does a Ethernet clock make sense.