Associated But Not Sending Traffic

[Curtis Larsen]

I am running ubuntu 10.04, wpa_supplicant 0.73 (not sure where to
verify version) with wpa_cli, and using Atheros AR9280.  I run
wpa_supplicant like this:

sudo  /etc/wpa_supplicant/wifi.conf -i wlan2 -d
sudo wpa_cli -a /sbin/wpa_action.sh

When I am at home on a Cisco 1140 series AP (Fat AP/IOS mode) with a
WPA2-PSK config I *never* have this issue.

When I am at work on a Cisco 1140 series AP in CAPWAP mode using
WPA2-Enterprise (PEAP MSCHAPv2) my laptop *always* stops sending
traffic within an hour.  Sometimes I have watched the ping resume
without intervention -but most times it does not.  It is a clean RF
environment.  I have verified with spectrum analysis and I am using
the 5ghz band (with 40mhz channels) both places.  There is low
usage/no usage besides me most times.  I manage both wireless
networks.  When this happens I have a client debug going on the Cisco
controller and it shows nothing happening, but an occasional .1x
re-auth or DHCP renew - but the controller thinks I am still connected
even though it cannot ping me.  wpa_supplicant/wpa_cli seems to think
I am connected as well even though I cannot ping the wireless client's
default gateway.

The crazy thing is that if I have a constant ping going from my
workstation to the wireless client it seems to always stay up.  If I
don't do this, within an hour I will stop sending traffic and have to
use "wpa_cli reassociate" to get things going again.

Is it just breaking when it wants to roam?  I have not configured
anything special for roaming.  When the client and the AP both *think*
each other are connected, but no traffic is passing, is there a log
somewhere that will indicate that the interface stopped passing
traffic?   I have no idea where to go next.  Any ideas?



Thanks,

Curtis