Legal?

I've disliked CircleID articles before, I'll probably continue to do so
in the future.

Not to break existing practice, I have issue with
Darren Miller's article, "Road Warrior at
Risk: The Dangers of Ad-Hoc Wireless Networking". While it's a
pretty good article on the dangers of ad-hoc wireless, I find the
authors attitude about sniffing wireless to be a bit too cavalier.

In
the wired world, port scanning is not deemed as trepass. It's
considered an annoyance. However, sniffing traffic and accessing
systems without permission is a definite no-no. Why should it be any
different in the wireless realm? Is it any different? This is an issue
that will probably need to be decided in court.

While tools like
AirFart will probably considered to be amongst the benign category,
tools like Kismet carry the possibility of landing a war-driver in
court. "But Kismet is a passive tool," you say? True, but it's passive
in the same manner that any wired sniffer is. Don't forget that Kismet
does create pcap-compatible packet dumps. Accessing those
capture files is probably the legal equivalent of accessing the network(s) that the traffic came from.

So...

If you're a traveler, you
should consider encrypting all of your traffic as it leaves your
computer (use a VPN) or only access generic sites that do not require
login or interaction. (Visit CNN, read /., etc.)

If you're a
journalist in search of a story (or anyone else armed with a sniffer),
stay off of other people's computers and don't capture their traffic.
If you're caught doing it, you may end up in cuffs.