On 24 October 2016 at 15:42, Simon Wunderlich <s...@simonwunderlich.de> wrote: > On Monday, October 24, 2016 3:33:24 PM CEST Johannes Berg wrote: >> > > I think it would be reasonable only if the target channel is the >> > > one we are using and we have done CSA. But when scanning non- >> > > operative channels I don't think this could work. >> > >> > this has been sleeping for a while.. :) >> > Would it make sense to rebase it and resubmit it for inclusion? >> > >> > Given the previous discussion we could change the logic as: >> > * always passively scan DFS channels that are not usable >> > * always actively scan DFS channels that are usable (i.e. CAC was >> > performed). >> >> Doesn't that contradict what you said above? >> >> If we scan, don't we possibly lose our CAC result anyway, since we went >> off-channel? In FCC at least? In ETSI I think we're allowed to do that >> for a bit? > > I believe going off-channel was allowed in general - in fact, some routers CAC > all channels on boot up and then keep the "usable" state forever.
I recall a discussion around this behavior [scan all on boot] a long time ago. I believe earlier ETSI spec revisions allowed it but recent ones made it more explicit that you can't cache CAC results like that but don't take my word for it. I don't have have the spec on me now so can't check. MichaĆ