Laurentiu-Sorin.Paun at imag.fr
Wed Dec 18 09:44:41 EST 2002
Please tell me if I understood the scan mechanism in HostAP:
-in firmware-based roaming mode (prism2_param wlan0 host_roaming 0), the
firmware do scans whenever the link quality is poor, and the AP with the
best signal level is chosen.
-in host-based roaming mode (prism2_param wlan0 host_roaming 1), the
firmware continues to do scans when the link quality is poor, but the AP
is chosen in the driver (prism2_host_roaming() ), looking also to
preferred_ap setting. In this mode; the driver can also command a part
How (which type - active or passive) are this scans done ? It seems that
the scans commanded by SIOCSIWSCAN are done also by the firmware, by
setting the HFA384X_RID_SCANREQUEST. What I don't really understand is
why a JoinRequest is made at every scan results
(HFA384X_INFO_SCANRESULTS) , even then when the best AP is in fact the
current AP. Does this slows the card someway, and if it slows, could one
eliminate the JoinRequest in the case of a same AP?
I've also noticed that for sta f/w>1.3.0, we can command a
HFA384X_RID_HOSTSCAN, and will we obtain a HFA384X_INFO_HOSTSCANRESULTS
frame. How is this different (what means "it keeps old association
status") ? It doesn't made/ We don't have to make a JoinRequest every time?
Abous the passive scans , I see that this can be do by a private ioctl.
How the passive is done by the f/w and what the results of these passive
scans are : a HFA384X_INFO_SCANRESULTS or HFA384X_INFO_HOSTSCANRESULTS
Thank you all for this great work,
Sorin PAUN mailto:Laurentiu-Sorin.Paun at imag.fr
Doctorant INPG http://drakkar.imag.fr/~lpaun
Laboratoire LSR-IMAG, Equipe Drakkar
681, rue de la Passerelle - BP 72 phone: (+33) (0)4 76 82 72 12
38402 St Martin d'Hères Cedex - France fax: (+33) (0)4 76 82 72 87
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