On Sun, Mar 15, 2009 at 09:22:38AM +0200, Kalle Valo wrote: > In my opinion also 2.4 GHz band needs checksum support. At least ERP > protection changes come to my mind, but maybe there are also others. Johannes mentioned Quiet IE as one such example. WMM can also change its parameters dynamically. Both of these need to be detected from Beacon frames. In addition, Channel Switch Announcement can be used to move the BSS to another channel, even on 2.4 GHz band. > Other option is that the hardware which does not support checksumming > would just pass beacons periodically to the stack, for example every 5 > seconds. Even though beacon filter is enabled in mac80211 it does not > prevent hardware from sending beacons. This is not the most optimal > solution, but there's not much choices if the hardware doesn't support > checksumming. While it would be possible to do that, it does not really solve many of the use cases where Beacon contents can change and the STA is required to take some action. For example, Channel Switch Announcement IEs would likely be missed if a Beacon frames is passed through that infrequently. I would assume the driver could enable this even if the hardware does not use checksumming to detect Beacon changes, but this may severely limit functionality in number of cases, so I'm not sure I would recommend this to be done in general. -- Jouni Malinen PGP id EFC895FA -- 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
