Client and AP mode on the same rt73usb hardware

Live forum:


11-08-2008 00:13:19

Now before I get flamed....I know that this is currently not possible on this hardware simultaneously...pity because that is exactly what I want (

However, I wanted to know if it is possible to safely have hostapd and wap_supplicant running against the same interface (wlan0) at the same time?

I want to have an external event telling me that I need to switch from being an AP to client and back again - this I can easily arrange

But, is there a way through hostapd_cli or wpa_cli to tell it to go to sleep and relinquish control of the interface so that the other process can take over without killing the currently controlling process?

Any other tips/tricks?


11-08-2008 16:32:26

I don't think that is possible, both processing will be conflicting with eachother. For example you don't want your AP perform scan operations breaking the association with all clients.

But from your post I understand you want something like "secondary mode", which is a repeater until the AP breaks down and then takes over. Adhoc might also be an option, but that depends on your exact requirements.

As for secondary mode, that is currently not implemented but on the todo list because the actual implementation should be very simple (for the driver, support already exists in mac80211).


12-08-2008 08:25:56

What I really want is

1 piece of hardware (rt73usb based dongle), which has
1 virtual network interface running as an AP, using hostapd, associating with clients as per normal and 1 virtual interface running as a client (connecting via PEAP) to another AP.

All on one radio!

Given that the hardware supports multiple virtual master interfaces, is it really not possible to do one master and one client? If its not, then why?


12-08-2008 09:05:03

No that is not possible, having a AP and STA interface is possible, but only when the STA is associated with its own virtual AP (which for obvious reasons is quite useless).

The problem is this
The device contains a register which value is the MAC address of the AP it is associated with, however in master mode that value is the MAC of the virtual AP interface. Hence it is not possible for the STA interface to write the MAC address of the AP it wants to associate with into that register.

The reason why it is possible for 4 AP interfaces to be created is that we can mask off some bits from the MAC address making those bits the index number of the interface after which 4 virtual AP interfaces can be created with sequential MAC adresses. But that won't help with mixing AP and STA interfaces.