On Tue, Aug 12, 2008 at 02:40:23PM +0200, Helmut Schaa wrote: > JFYI I already started to rework the existing scan code in mac80211 > (software scan) to do something like background scanning: > > 1) notify current AP about leaving the channel > 2) scan one channel It might be useful to leave this "one" as a parameter to allow easy experiments with scanning more than one channel at a time to reduce latency. Ideally, this--along the interval for background scans--could be something that is dynamically changed based on the expected traffic pattern. Whenever there is lot of data traffic being (mostly successfully) transmitted, it would be beneficial not to jump to other channels as frequently or for as long a time. If there has not been any data transmission for some time, it may be more acceptable to scan more frequently and to remain away from the operational channel for longer periods of time. Though, we should also keep in mind that background scans are going to increase power consumption on otherwise inactive situation, so setting a suitable policy for this can get quite complex. If we can somehow figure out whether there is periodic need for some traffic (e.g., VoIP), it would also be nice to be able to schedule the background scans to happen when there is no expected packet being sent or received at the time. Obviously, this gets much more complex, so this is not really something that would need to be included in the first version ;-). Anyway, it would be useful to keep in mind that there may be needs for making the background scan parameters change dynamically and there is need to be able to configure a suitable policy from user space. -- 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
