Uwe Klein wrote: > gary.limanap...@elisys.co.uk wrote: >> On Feb 15, 9:15 am, Uwe Klein <uwe_klein_habertw...@t-online.de> >> wrote: >> >>> gary.limanap...@elisys.co.uk 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? > > you usually get retransmission on collision from the hardware ( or the > driver ). > ( ethernet i am certain about, no firm knowledge about wlan though ) > This would be independent of the protocol used. > > this might help ( look for collision .. RTS/CTS packet ): > http://wlan.nat.sdu.dk/802_11standard.htm > > From my side this is an absolutely blind guess. But it could > well be a point to look at before trying to find an app bug > that may not be there. > > uwe
Remember that NTP uses UDP. UDP does not guarantee delivery, does not resend packets, etc. It sends a response to a request and doesn't know or care if the response was received or not! _______________________________________________ questions mailing list questions@lists.ntp.org https://lists.ntp.org/mailman/listinfo/questions