Re: capturing on both interfaces simultaneously

[Guy Harris <guy () alum mit edu>]

On Dec 12, 2011, at 1:10 PM, dragorn () durandal kismetwireless net wrote:

> About the only time you'll see beacons on non-basic rates is a
> greenfield deployment, of which I've *never* found one in the wild
> despite all the manufacturers caring about it.

Will we see any greenfield deployments any time before the last 11b/11a/11g adapter is crushed/recycled? :-)

(I guess you might get it in a corporate environment once every employee has been given a Shiny New 802.11n-capable 
{laptop, smartphone, tablet}, assuming they don't have to worry about vendors, customers, etc. not being able to 
connect *their* machines to the net.)

> Also under linux you will need to tune explicitly to CH+ or CH- to get
> 40mhz data packets, they will be silently ignored on just CH.  This
> means you must use netlink to set the channel as siochannel can't
> understand HT+ and HT-.
>
> I don't recall offhand if you'll still see basicrate packets on CH+ or
> CH- settings.
>
> Sniffing 11n in linux is a big mess.

Is that an issue of the Linux drivers?  E.g., is it the driver, or the adapter, that's ignoring packets if you don't 
specifically tune to the upper or lower channel?-
This is the tcpdump-workers list.
Visit https://cod.sandelman.ca/ to unsubscribe.