Doubt On Scanning Hidden AP

[Jouni Malinen]

On Fri, Apr 11, 2008 at 09:58:47AM +0530, Raghavendra wrote:

>    In some spec I came across the word "Scanning Hidden AP". 
> 
>  Can any tell me what is this hidden AP means?
> 
>  Also whether wpa supplicant is capable of doing that?
>  If so how to achieve it in wpa supplicant..I mean is there any special configuration that I have to do for scanning hidden AP using wpa supplicant?

In most cases, wpa_supplicant itself does not perform the scan; this is
left for the driver/firmware. In case of "hidden SSID" passive scanning
(just listening for Beacon frames) does not find the SSID for the AP and
an active scan with a specific SSID (i.e., sending Probe Request frames
with a specified SSID) is needed. wpa_supplicant can instruct the
driver/firmware to do this with scan_ssid=1 option in ap_scan=1 mode
(not all drivers support this, though). Alternatively, ap_scan=2 mode
can be used to leave all details of AP selection to the dirver/firmware
(i.e., wpa_supplicant is just configuring the SSID and security policy).

-- 
Jouni Malinen                                            PGP id EFC895FA