On Thu, Dec 18, 2008 at 09:05:08AM +0200, Jouni Malinen wrote: > received a CSA may not be that good of an idea. Then again, channels > that require radar detection should not really allow active scanning on > them in the first place. Just remembered one topic related to this that I was supposed to include here.. We should really start looking at using passive scanning more in some cases. The channel itself may not be completely restricted from active scanning, but especially when roaming to a new regulatory domain, it would be better to only use passive scanning until some life is found (i.e., a Beacon is received) and only enable active scanning after having learned which channels are allowed. This is actually a requirement in 802.11-2007, too (see 9.8.1). When receiving a CSA on a channel that requires DFS, but does not enforce strict passive-scanning-only policy (should there be such channels somewhere), it could be a good policy to drop that channel out from the currently allowed active-scan-channels and only add it back if passive scan find an AP Beaconing on the channel regardless of whether this is strictly speaking required or not by the standard. This type of dynamic mode changes for channels may need some work in mac80211, but it would probably be a good idea to do it. -- 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
