On Sun, Mar 28, 2010 at 12:43:32PM -0700, Jouni Malinen wrote: > On Wed, Mar 24, 2010 at 11:46:07PM -0700, Johannes Berg wrote: > > So this is merged, anyone want to implement it in mac80211 so we can > > start playing with it? I won't get around to it for quite a while. > > How about something like this? Based on a very brief test (walk 10 > meters toward the AP and then back ;-) this seems to be doing more or > less what I expect the feature should do. And for those interested in playing more with this, I added support for using the new signal strength threshold with the bgscan_simple module in wpa_supplicant. This seemed to provide reasonable behavior in an office environment with multiple APs and some overlapping coverage area in a test with ath9k. I used following wpa_supplicant configuration option for this particular test: bgscan="simple:30:-50:300" This uses background scan interval of 30 seconds if signal strength is below -50 dBm and 300 seconds if above. A new scan is triggered immediately if the signal strength drops below the threshold (or if it drops further 4 dB and it has been more than 10 seconds from the previous scan). Furthermore, I had manually configured the list of known channels that the APs here are using (scan_freq parameter). The connection did not die at any point (based on a continuous ping) and roaming behavior seemed reasonable, i.e., signal strength did not drop below -65 dBm or so before the new AP was already found. Background scans are also quite tolerable when the frequency list is limited and even more so, when remaining in the same location where the signal strength remains above the threshold. That 300 second interval could also be made much higher if it is desirable to avoid more or less all background scans since the immediate scan triggered by signal strength drop by itself should cover most use cases. -- Jouni Malinen PGP id EFC895FA -- 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
