Technical details of the Street View WiFi payload controversy

The latest privacy controversy with Google is that while scanning for WiFi access-points in their Street View cars, they may have inadvertently captured data payloads containing private information (URLs, fragments of e-mails, and so on).

Although some people are suspicious of their explanation, Google is almost certainly telling the truth when it claims it was an accident. The technology for WiFi scanning means it's easy to inadvertently capture too much information, and be unaware of it.

This article discusses technically how such scanning works.