I've been asked quite a bit lately the legal grounds for wardriving. Correct me in ANY of this if i am misunderstood/misinterpreting the laws and regulations. According to FCC rule part 15 for class B devices, it states: "This device may NOT cause any harmful interference AND (!!) this device *MUST* accept any interference it recieves, including interference that may cause undesired operation." Now, if i read part 15 for class B devices correctly, that means, driving by a place with my laptop on and in a scanning mode, (passive of course, no transmission on my part causing an otherwise "harmful" rf signal) and i pick up your WAP or high powered point-to-point net connection, and you're transmitting data over it, unencrypted or otherwise, my device MUST accept that interference. This is what i construde to be legal. Completely by the books. This is where the questions begin. What defines harmful interference? The FCC defines it as this: "(m) Harmful interference. Any emission, radiation or induction that endangers the functioning of a radio navigation service or of other safety services or seriously degrades, obstructs or repeatedly interrupts a radio communications service operating in accordance with this Chapter." Okay. In humanspeak to me, that reads, that my device cannot cause interference with GPS, police/rescue/fire, to the point of anything. Even slight degredation in signal is violation of this part. Do i read that correctly? Has no part in anything pertaining to the general public. There's alot of grey area involved in this. Not really much in line with the general public, but more ment for the companies that manufacture and install the hardware near government radios. Onto the matter of which this post is about. Wardriving. Hypothetical situation. I drive by in my car, with my laptop on, and running a scan program such as kismet. You, sitting in your house, using your laptop to check your email via the wireless network you own and control, and my laptop just happens to pick up the interference (although not intended for me) of your password, and the email from aunt flo. Do i see that as illegal? No. What i do with the data might be interpreted as illegal, but me driving by, picking up the signal, i do not consider illegal, as my gear is operating within it's designed spec. It is up you to secure your data using the provided means from the manufacturer (wep) or some other means. In that situation you did not have wep configured and turned on. Thus meaning your data is flying, clear text through the air. Now, the other side of this. Say you did have wep turned on, and i still managed to get a password or some data. (keep in mind i'm not transmitting ANYTHING. I'm simply allowing my hardware to show me the interference it's receiving.) I would say that if i sat there, and had enough data to crack your wep key, i would consider that a break-in attempt, hence illegal. It took effort on my part to sit in front of your house, gather data from your network, and run some kind of cracking system upon the data i've gathered. Now, if i'm standing across the street, at a dairy queen, aiming a dish at your house for the intent of gathering your data. This is illegal. I'm purpously trying to be malicious and gain access to your network. (not to mention blatently obvious)