[ForHackernews]

Their explanation sounds pretty fishy to me:

> Google blamed the mistake on a piece of legacy code from an experimental project that had been re-used to programme equipment on the Street View cars

Somebody at some point specifically wrote code to sniff data off wireless LANs.

[jewel]

In order to make a map of which wireless LANs are available, you switch the radio in receive mode and then cycle through the channels, capturing all packets. Then, you filter the packets for beacons. I believe when you "scan" for wireless networks, your wireless device is going to be doing something similar under the hood.

It'd be easy to accidentally leave debug logging turned on for the parsing code. Alternatively, if you use something off-the-shelf like kismet, the packet logs are saved in /var/log/kismet automatically.

[sk5t]

You never wrote a piece of code that dumps to a logfile more data than it really needs, as part of learning and design?

[Buge]

The data they wanted was the MAC addresses of the routers. With that information, then can then improve their maps geolocation by seeing what wifi networks are in range.

The problem is they grabbed more than just MAC addresses.