Wi-Fi, Mano a Mano Imagine a world where using Wi-Fi doesn't mean sacrificing security. It could happen.

Can you remember when there was no Wi-Fi at the big coffeehouse chains or the major airports or popular hotels? When it wasn't in most laptops, and if you were looking for a public Wi-Fi signal, you could go all day without finding one?

Now, Wi-Fi is anywhere businesspeople are likely to gather, in the office or not. It's estimated that half a billion users worldwide use Wi-Fi on about 2 billion shipped devices, according to the Wi-Fi Alliance in Austin, Texas, which certifies and promotes Wi-Fi technology standards.

Yet, for all its utility, Wi-Fi is almost too communal. Applications and resources, such as printers, in that networked environment are open to everyone, even if you just want to share them with a few. Public hot spots give you that feeling of swimming in the hotel pool at the end of the day: that you're taking a bath alongside people with whom you wouldn't share the elevator. Office hot spots are the same: Would you skinny-dip with every co-worker and office guest? (Some of them, maybe.)