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tcp ack clocking and delays

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Hello, i am doing some tests to observ the behavior of ack clocking in tcp. i understand that there are many reasons that affect ack clocking such as the presence of bottleneck and the presence of delayed ack , but i do not understand why or WHEN exactly it is affected, can anyone explain that to me ??

asked 12 Jul '15, 04:56

yas1234's gravatar image

yas1234
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accept rate: 0%


One Answer:

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This question is difficult to understand but i think I would suggest you read / watch:

https://en.wikipedia.org/wiki/Transmission_Control_Protocol#Data_transfer

Probably paying special attention to Flow and Congestion control. I may get shot for this, but I also found this page useful as it explains things fairly simply:

http://www.tcpipguide.com/free/t_TCPReliabilityandFlowControlFeaturesandProtocolMod.htm

AFTER reading these pages at least, you should watch this video: https://www.youtube.com/watch?v=Rj3RaEtVlVY

And now you should understand ACK Clocking and flow control. The basic answer is: pretty much always when more than one link type / speed is in use.

answered 12 Jul '15, 15:32

DarrenWright's gravatar image

DarrenWright
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accept rate: 26%

i do understand ack clocking ..but this is all theory.. my problem is when comparing theory to what happens in reality it is different ...i need to know this difference why is it caused or at least when it is caused..any help

(12 Jul '15, 15:49) yas1234

It would certainly help if you provide a packet capture that shows the scenario that you want explained. Can you upload an example to https://appliance.cloudshark.org/upload/ ?

(12 Jul '15, 22:18) mrEEde