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<DIV><FONT size=2>If you need to compute the jitter and delay between packets,
you need to process the timestamps attached to each packet (in the pcap_pkthdr
header). Regarding a microsecond precision, remember that packets are
timestamped not when the board receives them, but when the capture engine in the
kernel (being it windows or linux) processes them, and this can introduce a
delay of some microseconds (this is due to a number of reasons, e.g. interrupt
mitigation, the network card does not generate an interrupt for every received
packet, but rather batches the received packets for some microseconds in order
not to generate too many interrupts).</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Hope it helps</FONT></DIV>
<DIV><FONT size=2>GV</FONT></DIV>
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style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=antonio.ocampo@gmail.com
href="mailto:antonio.ocampo@gmail.com">Antonio Ocampo</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=winpcap-users@winpcap.org
href="mailto:winpcap-users@winpcap.org">winpcap-users@winpcap.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Wednesday, November 29, 2006 1:25
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [Winpcap-users] Delay and
jitter</DIV>
<DIV><BR></DIV>
<DIV><BR>I need to find the delay and jitter, how can I do this? i've tried to
use time.h but it just have precision of seconds and I need precision of
microseconds !!! I can't use getimeofday() because my program have to run in
windows and linux. </DIV>
<DIV> </DIV>
<DIV>Another trouble, when I tried to use the fields of the struct
pcap_stat</DIV>
<DIV> </DIV>
<DIV>if_drop: it shows me 0 always</DIV>
<DIV>bs_cap: it doesn't compile</DIV>
<DIV> </DIV>
<DIV>Any suggestions? I really need your help. Thanks in advance</DIV>
<P>
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