problems with Power Saving mode

kala_maico at kala_maico at
Wed Mar 3 10:54:18 EST 2004


I am facing problems on power management. Both Master and Managed modes
have timing problems

1) I put a client card (D-Link DWL-650, firmware RAM-upgraded to 1.7.4)
into power saving mode by issuing the command:

iwconfig wlan0 power period 10

According to the manpage of iwconfig this should set a sleep time of 10

>From another client (both clients run in managed mode under the same AP)
I ping the "sleeping" client obtaining an average rtt of 287 ms... shouldn't
it be 10 secs as I told the card to do? Anyway, here I can see the Power-Save
Poll frames as it should be, however they are much more frequent than I
expected (I expected 1 every 10 seca, the have a ratio of 3 per seconds
or so...)

2) I go under windows and use a Netgear 802.11g PCI card with its driver,
put it into power save mode, and ask for streaming traffic (live internet
radio). AP is hostap, card is Prism2 based with f/w 1.7.4. From a monitoring
station (monitor mode + ethereal) I see that the windows client issues Data:Nullfunc
frames with Power Mgt bit set to 1, but the AP goes on ignoring those frames.
I don't even see Power-Save Poll frames from the client, 
meaning that no
traffic is buffered for the station, or that traffic is buffered but hostap
doesn't wait for PS-Polls.

Streaming traffic has packets going in both directions (client - streaming
server and vice versa), so what I can imagine is that the outgoing traffic
(clent->streaming server) makes the AP think that the client left Power
Save mode.  Streaming server is a public server on the internet, and I access
it via browser.

Hostap is version 0.1.2 for both client and hostap, kernel is 2.4.22 for
client and 2.4.24 for AP.

Thanks and regards,
/Giorgio Calandriello

Attivazione GRATIS, contributo adesione GRATIS, modem GRATIS,

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