[time-nuts] ``direct'' RS-232 vs. RS-232 via USB vs. PPS decoding cards

[Chris Albertson]

The desktop PCs can each be configured with as many reference clocks
as you like.   That is independent of how many stratum 1 NTP servers a
company needs to operate.    Maybe you are running some stratum 2
servers on your routers and using more from the Internet.    All these
choices are independent of each other.

If you are serving Windows PCs then, I think those are all running
SNTP and then use just one NTP server

For most companies there really is no need to even have a GPS
receiver.  Being within 10  milliseconds is just fine so pool servers
will do.

> I would argue that you need at least three servers (and more like five). When given only two
> servers NTP simply dithers back and forth between them. It does not have
> a way to figure out which of two clocks is wrong. It will detect a missing clock, but
> not one that is simply off time by a bit.
>
-- 

Chris Albertson
Redondo Beach, California