On Tue, 17 Nov 2009 21:48:18 +0100 Johannes Berg <johannes@xxxxxxxxxxxxxxxx> 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> Looks good, maybe true four-address mode support will be available more widely, and this will no longer be an issue. Acked-by: Stephen Hemminger <shemminger@xxxxxxxxxx> -- 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
