Negative root delay is never reported with the current code.
This is the total of the network path delays to the stratum-1 computer
from which the computer is ultimately synchronised.
-In certain extreme situations, this value can be negative. (This can
-arise in a symmetric peer arrangement where the computers' frequencies
-are not tracking each other and the network delay is very short relative
-to the turn-around time at each computer.)
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@item Root dispersion
This is the total dispersion accumulated through all the computers back
to the stratum-1 computer from which the computer is ultimately