Listen to Cel phones live on the Internet?

An anonymous reader sent us this link (note that it is a shoutcast feed). Essentially, it is scanning open airwaves for cell phone calls, and rebroadcasting them over the Internet. Now I'm curious- is this invasion of privacy legal or just proof that we all ought to be encrypting everything? What do you think?

Comments

Expectation of privacy

[evilpenguin]

There is (IIRC) language in the communications act as amended that says something about the intent of the communicating parties. It is unlawful to intercept communications intended as point to point. Communication intended as a broadcast is not protected (obviously it is legal to listen to your local FM station!). It is also legal for non-licensed persons (all of this is in the US, beyond basic ITU rules regarding amateur radio, I know nothing of these things in other countries) to listen to, for example, two CB'ers or two radio amateurs talking because these are known and intended as broadcast media.

Also IIRC it used to be legal for licensed amateurs to monitor the entire spectrum, including the then RT bands (pre-cellular radio telephone), and, by extension, cellular and cordless phone traffic, but these privledges were specifically revoked in one of the sets of amendments somtime in the last 10 years. (Don't remember when).

Personally, I have always felt that if you want to keep something secret, keep your mouth shut. I do not think that anyone communicating by radio using some simple form of modulation (AM, FM, PCM, USB/SSB, etc.) should have any reasonable expectation of privacy. You can pass all the laws you like, but you can't prevent the interception of signals.

I'm an amateur radio operator. I drive around with a dual-band transceiver in my car (145MHz and 440MHz). Hams on these bands use FM modulation, just like a bunch of analog devices including (non-digital) cell phones. In urban areas there are so many transmitters all over the place that I often experience a phenomenon called "intermod" (intermodulation) which occurs when two radio carriers with wide separation in frequency happen to "beat" at the frequency I am monitoring (the difference between the two transmitter's carrier frequencies is equal to the frequency I am monitorning). If the conditions are right, my radio will then rectify the carrier and the demodulator will try to make audio out of the mixed signal. Often the result is gibberish, but often I hear two crystal clear conversations. This is an accident of physics. I doubt I could be prosecuted, since design of my radio tries to avoid this (lots of band pass filtering and such) and I had no intent to monitor anything I ought not to monitor. Nevertheless, I often hear ten and fifteen seconds of "private" conversation.

BTW, every time someone else buys a minivan and a cell phone, the problem gets worse. More transmitters on more frequencies equals more combinations that yield intermod. RF pollution is a semi-serious problem! (Cell phones are better for this than many systems, because the transmitter power levels are so small compared to more traditional methods of area-wide radio).

So, while the laws are pretty tight, you still shouldn't expect privacy. Even so, rebroadcasting cell phone conversations are something I think they would try to send you jail for...