Hi guys (sorry about my english),

I have some problems with some long range links, and I hope that somebody
can help me.
I am pretty sure that is a 802.11b timing problem.

The two links have these configurations:
1- 36 km link
   Soekris boards
   Linux & HostAP
   Senao 200mW
   24dBi antennas
   72m & 60m towers
2- 41 km link
   Soekris boards
   Linux & HostAP
   Senao 200mW
   1W amplifiers
   24dBi antennas (I don't have FCC problems :)
   90m & 72m towers

All RF calculations and values are ok (good link quality, stable 11Mbit
rate, >20 dB of system operating marging), the ping responses 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.
For example, with netperf I have an excelent bandwidht: 0.08 Mbits!!!
I am pretty sure that is a timing problem. I suppose that the packets start
to collision with ACK responses, and if the load increase on the link the
"snowball" starts.
The ping times go up and up (100, 300, 800, 1500, 4000...).

By the way, I have several <25 km links, they works great with similar
configurations (speeds over 3.5 Mbit)

I read an explanations about the timing problem on this article:
http://www.personaltelco.net/index.cgi/MaximumDistance

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, but this
require to change the cards or equipments on the towers.
I will like to found a solution on Prism 2.5, if it exist :)

Does anybody have an idea?
Does anybody know a working >35km link and what hard/soft it use?

Thanks for your time!

Regards,
Pablo.




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