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<div>On Mon, Mar 08, 2010 at 10:31:19AM +0100, Schulte Stefan wrote:</div>
<div> </div>
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<div>>> The 4way handshake stuff takes considerable time when roaming, so I take it that something with the configuration is wrong (either on supplicant or authentificator side), as I read comments that it shouldn't take longer than some 100 milliseconds.</div>
<div> </div>
<div>>4-way handshake should not really take more than couple of milliseconds</div>
<div>with a good implementation (in both ends)..</div>
<div> </div>
<div>I misread some figures... I came up with a new bottleneck, which is the background scan for new BSS. It seems that my client is switching over to the next AP only if the new one is out of reach for some time and therefor lost connection? How do you turn
on background scanning? Using the wext driver.</div>
<div>There are some settings for roaming treshold etc in the cisco wlan controller, but do I have to set the roaming behaviour in the supplicant aswell?:</div>
<div> </div>
<div>1268040566.248831: RTM_NEWLINK: operstate=1 ifi_flags=0x1003 ([UP])</div>
<div>1268040566.248859: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added</div>
<div>1268040566.256185: RTM_NEWLINK: operstate=1 ifi_flags=0x1003 ([UP])</div>
<div>1268040566.256205: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added</div>
<div>1268040566.256214: Wireless event: cmd=0x8b15 len=20</div>
<div>1268040566.256221: Wireless event: new AP: 00:00:00:00:00:00</div>
<div>1268040566.256248: Setting scan request: 0 sec 100000 usec</div>
<div>1268040566.256262: Added BSSID 00:24:98:99:37:12 into blacklist</div>
<div>1268040566.256274: CTRL-EVENT-DISCONNECTED - Disconnect event - remove keys</div>
<div>1268040566.256280: wpa_driver_wext_set_key: alg=0 key_idx=0 set_tx=0 seq_len=0 key_len=0</div>
<div>1268040566.256307: wpa_driver_wext_set_key: alg=0 key_idx=1 set_tx=0 seq_len=0 key_len=0</div>
<div>1268040566.256320: wpa_driver_wext_set_key: alg=0 key_idx=2 set_tx=0 seq_len=0 key_len=0</div>
<div>1268040566.256332: wpa_driver_wext_set_key: alg=0 key_idx=3 set_tx=0 seq_len=0 key_len=0</div>
<div>1268040566.256344: wpa_driver_wext_set_key: alg=0 key_idx=0 set_tx=0 seq_len=0 key_len=0</div>
<div>1268040566.256357: State: COMPLETED -> DISCONNECTED</div>
<div>1268040566.256364: wpa_driver_wext_set_operstate: operstate 1->0 (DORMANT)</div>
<div>1268040566.256372: WEXT: Operstate: linkmode=-1, operstate=5</div>
<div>1268040566.256400: EAPOL: External notification - portEnabled=0</div>
<div>1268040566.256406: EAPOL: SUPP_PAE entering state DISCONNECTED</div>
<div>1268040566.256412: EAPOL: SUPP_BE entering state INITIALIZE</div>
<div>1268040566.256421: EAPOL: External notification - portValid=0</div>
<div>1268040566.256427: EAPOL: External notification - EAP success=0</div>
<div>1268040566.358581: State: DISCONNECTED -> SCANNING</div>
<div>1268040566.358590: Starting AP scan (broadcast SSID)</div>
<div>1268040566.358596: Trying to get current scan results first without requesting a new scan to speed up initial association</div>
<div>1268040566.358640: Received 0 bytes of scan results (0 BSSes)</div>
<div>1268040566.358653: Cached scan results are empty - not posting</div>
<div>1268040566.358658: Selecting BSS from priority group 0</div>
<div>1268040566.358663: Try to find WPA-enabled AP</div>
<div>1268040566.358668: Try to find non-WPA AP</div>
<div>1268040566.358673: No APs found - clear blacklist and try again</div>
<div>1268040566.358677: Removed BSSID 00:24:98:99:37:12 from blacklist (clear)</div>
<div>1268040566.358687: Selecting BSS from priority group 0</div>
<div>1268040566.358691: Try to find WPA-enabled AP</div>
<div>1268040566.358696: Try to find non-WPA AP</div>
<div>1268040566.358700: No suitable AP found.</div>
<div>1268040566.358708: Setting scan request: 0 sec 0 usec</div>
<div>1268040566.358722: Starting AP scan (broadcast SSID)</div>
<div>1268040566.358793: Scan requested (ret=0) - scan timeout 30 seconds</div>
<div> </div>
<div> </div>
<div>Supplicant requested the driver to scan for bss now that former AP connection is already lost for several seconds?</div>
<div>And scan takes 3 seconds?</div>
<div> </div>
<div> </div>
<div>1268040569.364787: RTM_NEWLINK: operstate=0 ifi_flags=0x1003 ([UP])</div>
<div>1268040569.364806: RTM_NEWLINK, IFLA_IFNAME: Interface 'wlan0' added</div>
<div>1268040569.364858: Wireless event: cmd=0x8b19 len=8</div>
<div>1268040569.364966: Received 1195 bytes of scan results (3 BSSes)</div>
<div>1268040569.364987: CTRL-EVENT-SCAN-RESULTS</div>
<div> </div>
<div> </div>
<div>>> Currently it takes about 8 seconds roughly. The log output with timestamps and my wpa_supplicant configuration file can be found in this mails attachment.</div>
<div> </div>
<div>>No attachment found.</div>
<div> </div>
<div>Sorry, forgot to attach the logs.. stupid me. A small snippet is attached to this mail...</div>
<div> </div>
<div>My wpa_supplicant.conf:</div>
<div> </div>
<div>ctrl_interface=/var/run/wpa_supplicant</div>
<div> </div>
<div>ap_scan=2</div>
<div>#fast_reauth=1</div>
<div>eapol_version=2</div>
<div> </div>
<div> </div>
<div>### Logistics WPA2-PSK</div>
<div>network={</div>
<div> #proactive_key_caching=1</div>
<div> ssid="Logistik"</div>
<div> key_mgmt=WPA-PSK</div>
<div> proto=RSN</div>
<div> pairwise=CCMP</div>
<div> group=CCMP</div>
<div> #psk="+++++++"</div>
<div> psk=+++++</div>
<div>}</div>
<div> </div>
<div> </div>
<div> </div>
<div>Thanks for your generous help.</div>
<div> </div>
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<div><font face="Verdana, sans-serif">Mit freundlichen Grüßen</font></div>
<div><font face="Times New Roman, serif" size="3"> </font></div>
<div><font face="Verdana, sans-serif"><b>Stefan Schulte</b><font color="#0000FF"> </font></font></div>
<div><font face="Verdana, sans-serif">GB Finanzen und IT<br>
IT-Logistik</font></div>
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<div><font face="Verdana, sans-serif">Viega GmbH & Co. KG<font color="#0000FF"> <br>
</font>Zum langen Acker 7, D-57439 Attendorn<font color="#0000FF"> </font></font></div>
<div><font face="Arial, sans-serif">Telefon (+49) 2722 61 35 85, Telefax (+49) 2722 61 94 35 85<font face="Times New Roman, serif" size="3"> </font></font></div>
<div><font face="Verdana, sans-serif">Email: stefan.schulte@viega.de<font color="#0000FF"> <</font><a href="http://www.viega.de/">http://www.viega.de/</a>></font></div>
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