On Friday 01 April 2011 18:54:29 Gábor Stefanik wrote: > On Fri, Apr 1, 2011 at 9:51 AM, Christian Lamparter > <chunkeey@xxxxxxxxxxxxxx> wrote: > > On Friday 01 April 2011 05:12:45 Realman Namingston wrote: > >> ar9170-based devices record a fair amount of bad packets in monitor > >> mode both with the old ar9170usb and new carl9170 drivers. The packets > >> contain random BSSIDs, some measure of additional random data, and > >> seem to scale proportional to the amount of traffic occurring on the > >> observed channel. This behavior makes the devices rather unattractive > >> for use in Kismet and site survey applications. > >> > >> I assume this is due to a shortcoming of the hardware.. but is there > >> any potential fix possible? > > no, you misunderstood that completely: it's a shortcoming of kismet! > > > > quote: > > "Usually the wireless adapter is unable to transmit in monitor mode and > > is restricted to a single wireless channel, though this is dependent on > > the wireless adapter's driver, its firmware, and its chip set's features. > > Also, in monitor mode the adapter does not check to see if the cyclic > > redundancy check (CRC) values are correct for packets captured, so some > > captured packets may be corrupted." > > > > http://en.wikipedia.org/wiki/Monitor_mode > > -- > > 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 > > > > Isn't ar9170 the wireless-N version of zd1211? Because zd1211 > also had this problem with ZD_SNIFFER_ON. See > http://patches.aircrack-ng.org/zd1211rw_inject_2.6.26.patch inject? ??? quote from include/net/mac80211.h: "enum ieee80211_filter_flags - hardware filter flags These flags determine what the filter in hardware should be programmed to let through and what should not be passed to the stack. >>>>> It is always safe to pass more frames than requested, but this has negative impact on power consumption. <<<<<" so, if you don't want the garbage then don't enable monitor mode. OR set the appropriate FIF_ filter flags and hope the mntr setting doesn't affect the way how the hardware/firmware/driver/stack marks "bad" frames. Regards, Chr -- 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
