<P>
<BR>
Hi,<BR>
<BR>
The observed results is wrong.Whenever you go for re-association with new AP,either full IEEE8021X echange or EAPOL start wont occur,only EAPOL key will be exchanged,that to with new PMKID.If you are going back to first AP,First PMKID-1 will be used to re-associate with the same,etc..<BR>
<BR>
If you send the sniffer capture,propably i can give you more feedback about the scenario.<BR>
<BR>
Please give the clear picture about your setup.<BR>
<BR>
Thanks<BR>
Ambedkar.R<BR>
<BR>
<BR>
On Mon, 17 Sep 2007 Tilman Schoop wrote :<BR>
>Hi all,<BR>
><BR>
>I have seen a strange behaviour when examining the roaming in<BR>
>a WPA2 environment.<BR>
><BR>
>There are two phenomena:<BR>
>1) no pmkid is sent during roaming reassociation telegram<BR>
>2) the same pmkid (appearing in log as pmkid of one of the<BR>
> two access points) is sent with both (Re)association requests<BR>
> to the different APs.<BR>
><BR>
>I can reconstruct this behaviour in the following environment:<BR>
><BR>
>There are 2 Cisco access points and I test the roaming with a<BR>
>client using ipw driver (alternatively using a laptop with<BR>
>hostap driver in host_roaming=0 mode) and a wpa2 configuration<BR>
>(wpa_supplicant is V0.5.7).<BR>
>The access points are located so close to eachother that<BR>
>I can see both access points in the scan_results.<BR>
><BR>
>To replay the first case of the above mentioned:<BR>
>I start wpa_supplicant when radio is in range and<BR>
>roam between the APs without loosing the connection.<BR>
>=> every roaming leads to a full WPA2 authentication<BR>
><BR>
>To replay the second case of the above mentioned:<BR>
>When I leave the radio area and get disconnected, then<BR>
>going back to reconnect to AP1, afterwards<BR>
>I see that pmkid is sent in the Reassociation telegrams,<BR>
>but every roaming the sent pmkid is the same. So then,<BR>
>the roaming from AP2 to AP1 goes fast (because the pmkid<BR>
>pertains to AP1), but when going from AP1 to AP2, this<BR>
>one does not accept the pmkid (of course, it is pmkid<BR>
>of AP1) and does a full authentification.<BR>
>=> every roaming from AP1 to AP2 leads to a full WPA2 authentication<BR>
><BR>
>If I test with only one AP and get disconnected and connected again<BR>
>the pmksa caching is used to do a fast reauthentication.<BR>
><BR>
>Has anyone seen this behaviour?<BR>
>is it a problem on the client side or with the AP configuration?<BR>
>how can I configure this to get a smart/fast/lossless roaming?<BR>
><BR>
>I suspect a wrong cache behavior of wpa_supplicant, when<BR>
>there is no CTRL-EVENT-DISCONNECTED, and driver asyncronically<BR>
>signals "Associated to new AP". Any ideas?<BR>
><BR>
><BR>
>Greetings<BR>
><BR>
><BR>
>Tilman Schoop<BR>
><BR>
><BR>
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