[Ns-developers] radiotap + prism

[Mathieu Lacage]

On Fri, 2009-05-15 at 17:15 +0200, Nicola Baldo wrote:
> Hi Mathieu & everybody,
> 
> back to this radiotap issue, I've made a new implementation of radiotap 
> + prism support, trying to address the issues that you raised.
> 
> The new code is available for review here:
> http://codereview.appspot.com/67056/show

thanks, looks great. posted comments there.


> By the way, I would like to point out that, with Timo's WifiPhyTags, all 
> the needed information would be already embedded in the Packet, and we 
> would get rid of all those function parameters which are rather ugly.

nice try :)

> > in the real world, the radiotap header is used _only_ for received packets, not
> > transmitted packets.
> 
> That's not true. Just take a single madwifi device, and do wlanconfig 
> create two virtual devices, one in sta mode and the other in monitor 
> mode. In this case you will be able to see outgoing packets which have a 
> radiotap header. The radiotap header obviously cannot show the signal 
> and noise fields for outgoing packets, but other fields such as datarate 
> and mactimestamp are there.

I still feel that this is a gross hack. You are right to point out that
madwifi does that but, it does not make it any less ugly. I wonder what
the in-kernel linux code does in that case.

Mathieu