[ntp:questions] Windows time question.

Richard B. Gilbert rgilbert88 at comcast.net
Fri Apr 22 16:07:34 UTC 2011

On 4/22/2011 11:22 AM, unruh wrote:
> On 2011-04-22, Rob<nomail at example.com>  wrote:
>> Hal Murray<hal-usenet at ip-64-139-1-69.sjc.megapath.net>  wrote:
>>>> I would have hoped that the pool folk kept their documentation up-to-date,
>>>> so I'll post that on their list.  You didn't mention how to control the
>>>> number of servers uses - is it just multiple "pool" entries?
>>> You only need one pool command.
>>>    pool<server-name>
>>> will use as many addresses from server-name as it needs.
>>> If it doesn't get enough with the first DNS lookup, it will try
>>> again in a minute or so, and keep trying until it gets enough.
>>> The default is to collect 10 servers.
>> If I were involved in the pool I would call that abuse!
>> The pool DNS lookup now returns 3 servers, used to be 5.
>> When everyone uses 10 servers the load on the pool as a whole is
>> twice what it would need to be, and 3 times what would be the minimum
>> reasonable value.
> I agree. It is absurd. It seems to indicate that the ntp folk really
> really do not trust the pool, and figure that if you get fewer than 10, you have a
> reasonable chance that a majority will deliver bad time. Ie, they appear
> to feel that the pool is a pretty useless souce of time.
>> Do the pool managers know that it works that way?

Anyone who doubts the accuracy, legitimacy, etc. of pool services should 
be able to purchase a GPS timing receiver and get the time from "the 
horse's mouth".  The investment required is about $100 US at a minimum. 
Or, just about every country in the world has its "National Bureau of 
Standards" equivalent and many broadcast a time signal; e.g. WWV, WWVA, 
WWVB, WWVH, JJY, CHU(?), etc.

If you're really paranoid, you can spend a small fortune and get an 
"atomic clock" of your very own!  The NBS will cheerfully calibrate it 
for you!

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