[NCLUG] Need help identifying a mystery network

[Michael Dwyer]

Marcio Luis Teixeira wrote:
> 
> Today I just received a 802.11b card and set it up on my laptop. I do not have
> an access point at home, so I wasn't expecting to get a connection, but much
> to my amusement I got a moderately strong signal and my machine was assigned
> an IP address via DHCP (though, alas, I cannot connect to anywhere). The

As you surmised, your neighbor probably has a Linksys wireless access
point.  Since they didn't bother changing the name of the node, they
probably also didn't bother to change the default passwords and security
keys... >:)  A nice person would find that neighbor and warn them.

You will find this site on NetStumbling, or 'wardriving' interesting:
http://www.netstumbler.com/

Also, check last year's DefCon presentations for a presentation on this
subject.  It is pretty scary.  Once you have a NetStumbler running, go
drive by BestBuy...  Wireless networking is currently banned from my
business network right now because of this.

> network name is "linksys", which I assume is the brand of the wireless access
> point. Anyhow, I'm a bit curious to know whose network I'm getting connected
> to, but so far I haven't found anything out. The IP address I get assigned is
> a class B address in the network 169.254.0.0 . I did a "whois" search and I
> get the following information:

I don't know where it is officially documented, but I know I have seen
it documented somewhere...  169.254.0.0 is the network for an
unconfigured network.  In particular, it is where Windows boxes go if
DHCP fails.

> Does anyone know who these people are? Why do I end up on their network? I
> really doubt I'm getting a signal all the way from California :) Do these
> people outsource IP addresses to some local access provider and perhaps one
> of my neighbors subscribes to that provider and has a wireless access point
> in their home? Do any of you guys recognize the IP address as belonging to
> some local ISP?

Typically, people buy a wireless system, then forget that wireless goes
through walls...  It is often unintentional. (Ask Lightsource
Interactive if they are intentially serving wireless internet to the Old
Town area... I recall their access points making a strong showing on the
stumbler when I went through there.)  At the DefCon presentation, the
presenter told of a successful connection at 13 miles, across the Bay. 
He was, of course, using very directional antennas...  but keep in mind,
some people are building directional antennas using Pringles cans...
On the other hand, there is a sort of altruistic gift that some people
give.  Some people set up wireless access points for the express use of
other people.  A friend of mine had an apartment across the street from
the Paris coffee shop in Denver.  He served bandwidth to the coffee shop
-- mostly so he, himself, could work from the shop, but he would have
happily shared with anyone else who wanted it.
If I ever get wireless at my house, I will probably set my access point
outside my firewall and will let people use it if they'd like... I can't
imagine too many of my neighbors being that savvy, though...
 
> Also, are there any techniques or software that I can use to find the source
> of the signal? I think it might be a fun project to drive around in my car
> and try triangulate the source of the signal, perhaps based on signal
> strength (or, I could, alternatively, get a life, but that wouldn't be nearly
> as much fun). Then I could knock on their door and tell them to lock down
> their network so bored people like me won't keep mucking around with it :)

Once again, look up netstumbling.  With a directional antenna, you can
try to triangulate where the signal is coming from.  Lacking one, you
can just watch the signal meter and see where it gets stronger -- that's
how I find SprintPCS towers. :)