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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi guys,<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>We are trying to do some measurements with the hostAP driver
code. Specifically we are interested to measure the delay that it takes
from the time the frame is scheduled for transmission in the driver and to the
time that the ACK for it comes back. Now, it is easy to start a timer at
the point when the packet is queued for transmission, but how can we know when
the ACK is received? Is there some kind of an interrupt generated when the
802.11 ACK is received? Also, another problem is how to time this to a
high degree of precision. We were thinking of using the jiffies value for
this, but that value only has precision of 10 to the power of -2. We
would be interested in something that has precision in the microseconds, like
in tcpdump. What could we use to get such a precision?<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Thank for any information.<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Boris<o:p></o:p></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p> </o:p></span></font></p>
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