On Tue, Nov 17, 2009 at 02:46:25PM +0100, Johannes Berg wrote: > A number of people have tried to add a wireless interface > (in managed mode) to a bridge and then complained that it > doesn't work. It cannot work, however, because in 802.11 > networks all packets need to be acknowledged and as such > need to be sent to the right address. Promiscuous doesn't > help here. The wireless address format used for these > links has only space for three addresses, the > * transmitter, which must be equal to the sender (origin) > * receiver (on the wireless medium), which is the AP in > the case of managed mode > * the recipient (destination), which is on the APs local > network segment > > In an IBSS, it is similar, but the receiver and recipient > must match and the third address is used as the BSSID. > > To avoid such mistakes in the future, disallow adding a > wireless interface to a bridge. > > Felix has recently added a four-address mode to the AP > and client side that can be used (after negotiating that > it is possible, which must happen out-of-band by setting > up both sides) for bridging, so allow that case. > > Signed-off-by: Johannes Berg <johannes@xxxxxxxxxxxxxxxx> ACK -- we get these complaints fairly often... I don't think I've sent the 4addr stuff to Dave yet. Should I just take this through my tree? John -- John W. Linville Someday the world will need a hero, and you linville@xxxxxxxxxxxxx might be all we have. Be ready. -- 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
