[ath9k-devel] vifs management

[Ben Greear <greearb@candelatech.com>]

On 11/06/2010 05:33 PM, Jo?o Maur?cio wrote:
> After some testing, I've got the some results as before: when I issue the "echo add > ... wiphy" command while I'm associated with some AP on wlan0, I get
> deassociated after a few seconds. Also, no interface can get associated before I issue "echo del=phy ... wiphy" until I've just my primary interface. Long story
> short, I can't make wiphys work. Any thoughts?

There is no way (as far as I know) for a radio to be on two channels at once.  Using
wiphys lets the virtual phys switch every 500ms or so between channels, but that means
any VIF on the other channel cannot do anything useful.

I think that if you need to be on two different channels at the same time you are going
to have to get multiple NICs.

If you put multiple VIFS on the same phy, then they can all work together
without too much interference with each other.  The restriction is that they
must all be on the same channel (scanning on different channels is OK, but
the eventual association must be on the same channel as the other VIFs).

Thanks,
Ben


>
> What's the real difference between creating wlan0, wlan1, ... wlanN "based" on phy0, phy1... phyN and wlan0, wlan1, ..., wlanN always "based" on phy0??
>
> Thanks
>
> 2010/11/4 Jo?o Maur?cio <joao.goncalves.mauricio at gmail.com <mailto:joao.goncalves.mauricio@gmail.com>>
>
>         My method assumes that all your stations will be on the same
>         frequency.  When that is the case, two different VIFS can communicate
>         to two different APs concurrently.  You do not have to play any
>         special tricks.
>
>         If you want your VIFs to function on different channels, then you
>         are going to have to attempt virtual wiphys probably..and my initial
>         attempt at using them went poorly.
>
>
>     Ok, I'll try again to make it work with virtual wiphys and report the outcome later. Shouldn't it be "straightforward" with just 2 virtual interfaces?? Is
>     there any known major issues (my NIC's chipset is the ar9285)?
>
>     A log with a successful attempt would be marvelous.
>
>     Thanks
>
>


-- 
Ben Greear <greearb@candelatech.com>
Candela Technologies Inc  http://www.candelatech.com