about scan and probe request
belle.shi at yy.com
Fri Oct 23 00:25:26 PDT 2009
is there anyone who read the standard "Part 11: Wireless LAN Medium
Access Control (MAC) and Physical Layer (PHY) Specifications" ?
and i spend two month to read the stardard, and i read a few code
of wpa_suppliant and wpa_gui,there is one question: the scan have two
mode:active or passive,but when i run the wpa_gui, there is only scan
button, in the standard the scan request is like
but there are only three MAC frame formats:data frame, control frame
and Management frame, and there is no scan frame, there is only a Probe
Request frame, so i am stumped, what's the relationship between
MLME-SCAN.request and Probe Request frame, is the MLME-SCAN.request and
Probe Request frame only in different layer? but the items is also
different, the MLME-SCAN.request have:(
BSSType, BSSID, SSID, ScanType, ProbeDelay, ChannelList,
MinChannelTime, MaxChannelTime), but the Probe Request frame body
only have two parts: SSID
and Supported rates. and in my view, i think the active scan is to
send Probe Request frame, and the passive scan to receive the beacon
frame, is it right?
thanks for advance!!
More information about the Hostap