Johannes, Thanks a lot for your comments. I will fix the presentation accordingly. The code base for the lecture is indeed not the latest wireless-testing tree. > Hey that got long! The presentation is also quite long... Regards, Rami Rosen On Thu, Aug 20, 2009 at 12:22 PM, Johannes Berg<johannes@xxxxxxxxxxxxxxxx> wrote: > On Thu, 2009-08-20 at 10:02 +0300, Rami Rosen wrote: > >> http://tuxology.net/wp-content/uploads/2009/08/wirelessLecHerzelinux.pdf > > had a quick look > > * almost all drivers support passive scanning -- all the modern ones at > least -- maybe some old drivers don't, but all using cfg80211 do > * your presentation is based on old code -- all the code stuff about > scanning is already outdated in wireless-testing > * you can scan for multiple specific SSIDs and channels: > iw wlan0 scan freq 2412 ssid foo bar baz > * iw has a better IE parser, so showing a result from that may be more > instructive > * code stuff about authentication/association is also outdated already > * the STA_MLME_DISABLED stuff no longer exists > * AP MLME will never be in the kernel, not just not in the near > future :) > * raw packets still go through the mac80211 stack, they arrive in > monitor_start_xmit() or so > * four-address format is not necessarily used only for WDS, the > standard doesn't define uses for it (ToDS = FromDS = 1) > * an AP may transmit nullfunc (!) frames to tell clients it has no data > buffered, but it never transmits frames with the PM bit on > * power timeout 5 is described incorrectly -- it doesn't go to sleep > for 5 seconds, it actually stays awake for 5 seconds after each > packet transmission -- the time spent asleep is calculated based on > the DTIM period etc. Cf. 04fe20372e70685d9f15966216cdffd3795fe590. > * STA may wake up in response to TIM[AID] == 1 instead of sending > PS-poll, which we do depends on the timeout (iwconfig wlan0 power > timeout 0 == PS-poll, iwconfig wlan0 power timeout 100ms == send > nullfunc and stay awake for 100ms) > * "paramter" typo > * ibss is in net/mac80211/ibss.c and has been for quite a while > * PM in IBSS is not implemented typically > * s/80211.s/802.11s/ > * s/80211.n/802.11n/ > * you can change the channel with iw (iw phy set freq ...) but it isn't > really useful unless you're AP/monitor (and rejected otherwise) > * Fedora no longer updates from wireless-testing afaik > * wmaster0 is no longer created > * assigning interface_modes doesn't set the mode, it just sets the > possible modes :) > * you can also call iterate_interfaces_atomic() in irq context > * nobody cares about the wireless extensions version any more :) > * for sniffing you may care about "iw dev <devname> set monitor <flag>*" > > Hey that got long! > > johannes > -- To unsubscribe from this list: send the line "unsubscribe linux-wireless" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
