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<DIV><FONT size=2>I try this, but didn't work.</FONT></DIV>
<DIV><FONT size=2>I suppose that the problems is that the sender doesn't
receive the ACK in time, and thinks that the packet is lost. </FONT></DIV>
<DIV><FONT size=2>All RF are ok (good link quality, stable 11Mbit
rate, >20 dB of system operating marging), the ping response are
excelent (I can send 1000 packets, without loose anyone, with a delay time
between 4 and 12 ms), but if I load the link the things come very
bad. </FONT></DIV>
<DIV><FONT size=2>For example, with netperf the bandwidht is about 0.08 Mbits,
getting a little better with retransmissions set to 0, but below
to 0.3 Mbits.</FONT></DIV>
<DIV><FONT size=2>By the way, I have several <25 km links, and they works
great with similar configurations (speeds over 3.5 Mbit), I have this problem
only with a 36km and a 41km link.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>This article explains the problem: <FONT size=2><A
href="http://www.personaltelco.net/index.cgi/MaximumDistance">http://www.personaltelco.net/index.cgi/MaximumDistance</A></FONT></FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>I found that StarOS solve this problem with the Agere cards,
and Cisco has a distance factor on they bridges to adjust the 802.11b timing.
</FONT></DIV>
<DIV><FONT size=2>I don't know if the ACK times are firmware or driver
controlled, and if they can be modified on Prism.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Does anybody have an idea?</FONT></DIV>
<DIV><FONT size=2>Does anybody know a working >35km link with Prism and
HostAP?</FONT></DIV>
<DIV><FONT size=2>If the answer to the last one is no, does anybody know a
working >35km link and what hard/soft it use?</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
<DIV><FONT size=2>Thanks in advance!</FONT></DIV>
<DIV><FONT size=2>Pablo.</FONT></DIV>
<DIV><FONT size=2></FONT> </DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=jkmaline@cc.hut.fi href="mailto:jkmaline@cc.hut.fi">Jouni Malinen</A>
</DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=hostap@shmoo.com
href="mailto:hostap@shmoo.com">hostap@shmoo.com</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, November 19, 2002
2:13</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Timing problems.</DIV>
<DIV><FONT size=2></FONT><FONT size=2></FONT><BR></DIV><!-- Converted from text/plain format -->
<P><FONT size=2>On Mon, Nov 18, 2002 at 10:30:02PM +0200, Vladimir Ivaschenko
wrote:</FONT> </P>
<P><FONT size=2>> BTW, are there any 802.11b cards available which allow to
change CIFS/DIFS</FONT> <BR><FONT size=2>> intervals or to disable
retransmissions with open source drivers?</FONT> </P>
<P><FONT size=2>I'm not aware of how these intervals could be changed in
Prism2 cards,</FONT> <BR><FONT size=2>but you should be able to setup
retransmission limit with Host AP</FONT> <BR><FONT size=2>driver. If you set
the maximum number of retransmission to 0, there</FONT> <BR><FONT
size=2>should not be any retransmissions even if the frames are not</FONT>
<BR><FONT size=2>acknowledged. I haven't tested this thoroughly, but you can
test it by</FONT> <BR><FONT size=2>running 'iwconfig wlan0 retry 0'.</FONT>
</P>
<P><FONT size=2>-- </FONT><BR><FONT size=2>Jouni
Malinen
PGP id EFC895FA</FONT> <BR><FONT
size=2>_______________________________________________</FONT> <BR><FONT
size=2>HostAP mailing list</FONT> <BR><FONT size=2>HostAP@shmoo.com</FONT>
<BR><FONT size=2><A
href="http://lists.shmoo.com/mailman/listinfo/hostap">http://lists.shmoo.com/mailman/listinfo/hostap</A></FONT>
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