Re: Very rapid polling

gary.limanapier@xxxxxxxxxxxx wrote:
On Feb 15, 9:15 am, Uwe Klein <uwe_klein_habertw...@xxxxxxxxxxx>
wrote:
gary.limanap...@xxxxxxxxxxxx wrote:
Just joining this discussion as we have noticed NTP request from our
Authorised Server every 300ms on our LAN. They occur only between the
Time Server and the WiFi Tablet during a socket connection while there
is a low signal strength. The Tablet sends its own NTP request with a
Poll Interval of 4 (16 seconds). The server returns its response
increasing the Poll Interval to 10 (1024 secs). The server then keeps
sending this same packet every 300-500ms.
Does the ntp process submit these packets repeatedly or
are you seeing some (uncalled for) "collision/resend" action due to
issues with the wlan connection?

uwe

Would it matter if the packet colided? NTP is using UDP and I can't
see from the packet analyser that it is expects a response back. When
it does work with a known good machine there is no acknowledgement of
the packet being sent. Do you think that there another level of
operation in the network that I am not seeing with the packet analyser?

How would an NTP packet collide? With what? NTP packets are always
unique. If a client sends a packet to the server it will get a response
(if it responds at all) with an identical-looking packet. If there is no
response either the server is dropping the request or there is a
firewall in the way dropping the requests. This is not an ethernet
packet and the nature of UDP is that there is no automatic resend.

Danny
.

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