On Thu, Jan 01, 2015 at 06:30:50PM -0500, Brad Smith wrote: > On 01/01/15 17:14, Christian Weisgerber wrote: > >My OpenBSD laptop, iwn(4), doesn't roam between my two access points. > >It's a sorry sight when it struggles to push a signal through the > >rebar floor instead of switching over to the other access point a > >meter away. > > > >Is this a limitation of OpenBSD's WLAN support or should I blame > >the access points? (Two stupid consumer APs with the same SSID and > >on the same network segment.) > > > >Searching for WLAN roaming leads to vague references to IEEE 802.11f, > >but it's unclear to me whether this is required for roaming or just > >intended to improve it. > > Roaming is done by the client. This is an OpenBSD issue. It needs > the relevant support in the drivers and 802.11 layer.
That's correct. Clients are supposed to handle roaming by choosing a different AP and sending a re-association request frame. The standard doesn't specify details so the underlying mechanics are up to the implementation (apparently some vendor-specific extensions exist). I don't believe OpenBSD wireless clients support this transparently. A manual re-assocation is necessary, perhaps with an explicit AP bssid given to ifconfig. 802.11f implements AP<->AP communication about re-associations and is supported via hostapd(8).
