From: Daniel Aguayo <aguayo@am...> - 2001-11-28 23:53:42
I'm looking at signal strength numbers from some Aironet 340 PCI cards
running in ad hoc mode under OpenBSD 2.9. The report from ancontrol
looks like this:
[1/10]: 00:40:96:46:fc:af, 10.0.0.21, sig: 20, noise: 0, qual: 0
[2/10]: 00:40:96:42:20:e5, 10.0.0.23, sig: 16, noise: 0, qual: 0
[3/10]: 00:40:96:38:7b:c3, 10.0.0.13, sig: 13, noise: 0, qual: 0
The other day I recorded the signal strength between one pair of
nodes, spaced apart by no more than three feet, every three seconds.
I got the following numbers:
No values between 36 and 65 were reported, and even ignoring that
fact, this seems like nonsense to me. I can't even reproduce the
problem today, but I would really like to know what I can trust about
the numbers being reported by ancontrol, what they imply as far as
observed loss rate or maximum throughput, how they're being recorded,
etc. What are the units on sig?
FWIW, I'm trying to ascertain how I can apply these numbers to route
selection in a medium-sized ad hoc network. Any sort of insight or a
pointer to another resource would be very much appreciated. Thanks in
From: David Boreham <david_list@bo...> - 2001-11-29 00:06:40
> No values between 36 and 65 were reported, and even ignoring that
> fact, this seems like nonsense to me. I can't even reproduce the
> problem today, but I would really like to know what I can trust about
> the numbers being reported by ancontrol, what they imply as far as
Yeah, I see the same thing. One theory is that in ad-hoc mode,
in contrast to infrastructure mode, the card is unable to measure
beacon strength accurately when the link is quiet.
Try creating traffic (use ttcp, ftp, etc) and see if the signal level
figures look more sane.