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<p class="MsoPlainText">Hello everyone, <o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">We are currently doing experiments where we try to measure the packet arrival times (time differences) at a switch.<o:p></o:p></p>
<p class="MsoPlainText">Since OpenFlow does not support this, we are trying to measure the time at the controller, i.e. when the corresponding packet_in message is received at the POX controller (in the Packet_in event handler).<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">This works to some extent in POX (in contrast to Ryu), but we were wondering if the accuracy and granularity of the timing measurement can be improved somehow.<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText">For example, is there a way to add a timestamp at a low level in the POX code, when the OF messages are received, e.g. before messages are queued and wait for the corresponding handler to be scheduled (if this is how it works)?<o:p></o:p></p>
<p class="MsoPlainText"><o:p> </o:p></p>
<p class="MsoPlainText"><span style="font-size:10.0pt"><o:p> </o:p></span></p>
<p class="MsoNormal">Best regards,<o:p></o:p></p>
<p class="MsoNormal">Farzaneh<o:p></o:p></p>
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