On Wed, 2007-03-28 at 11:55 +0200, Michael Buesch wrote: > I think we need at least two "stages" for this config. > One that says: Get all packets with bad FCS > And one that says: Get all packets with bad FCS and everything else > that looks like a signal, which is probably your microwave oven, though. I agree. > So, when these packets are passed up the stack the PLCP is stripped. > I think we should make the stack aware of the PLCP (and add an RX flag > PLCP_available) so that it is able to check the PLCP checksum. > Otherwise the only way to detect your microwave oven from the packet > stream would be failed FCS. Which would also most likely failed then, but > I think it's probably useful for the user to see the PLCP, too, on > a mon interface. > > So we need RX flags "PLCP_available" and "Not_checksummed". Also "PLCP checksummed" or such. And we need to think about how we represent the PLCP in radiotap. The PLCP header has different lengths depending on the type of PHY used, for Clause 17 (A) it is 40 bits, for the others (I think) it is 48 bits. For N I think the whole notion was changed a bit with the stuff being defined in terms of microseconds and not bits. It'd be useful to make this part of radiotap but it'd need a length byte too. I propose always padding it to a multiple of 8 bytes with a length byte as the first byte. For mac80211, we'd add a new item s16 plcp offset that tells us where in the radiotap header that the driver generated the plcp header can be found so that in the RX path we don't need to parse the radiotap header to find the PLCP if necessary. johannes
Attachment:
signature.asc
Description: This is a digitally signed message part
