TWC (AS11351) blocking all NTP?

Doug Barton dougb at
Mon Feb 3 21:15:46 UTC 2014

On 02/03/2014 12:50 PM, John R. Levine wrote:
>>> I was thinking that the servers on any particular network are
>>> a small set of exceptions to a general rule to rate limit outgoing
>>> NTP traffic.
>> allows any NTP operator to opt-in to receive NTP
>> traffic should their clock be available and accurate.
> I believe you, but I don't believe that the set of servers
> changes so rapidly that it is beyond the ability of network operators to
> handle the ones on their own networks as a special case.

The list is large enough, and changes often enough, that filtering on it 
isn't likely to be successful. Also, the list of what are "your" servers 
can change without warning.


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