Let me say thanks to the Women's Business Council of the Southwest for inviting me to teach them about laptop safety. The business backgrounds of the members ranged from huge company manager to sole proprietor to corporate lawyer and everything in between. That's what made their questions so interesting, because they came from all directions.

Wi-Fi security issues got plenty of time during my presentation and plenty of follow-up questions from the audience. It's hard for many people to think a free Wi-Fi provider, like a local coffee shop, would lead them into a security sinkhole.

Don't focus on the Wi-Fi provider, because they are not the ones violating your security. You must worry about the other patrons sitting in the coffee shop with their laptops open. Every Wi-Fi chip set, whether added on with a PC Card or built into newer laptops, automatically operates in what we call “promiscuous” mode. In other words, it will connect to any other Wi-Fi device it can. This makes security difficult, because all the other promiscuous laptops can see your laptop, just as you can see them with a little bit of effort. While the vast majority of other laptops are discrete in their connections, one hacker can ruin the love-in for everyone. Hence the constant need for caution and protection.

One way to avoid falling into the clutches of a Wi-Fi hacker is to avoid Wi-Fi and use a cellular data service instead. All the major cell phone carriers offer data networking, often called Mobile Broadband or Data Networking or Wireless LAN (WLAN) (Compare WLAN Security products) or Wireless Wide Area Network (WWAN) or some other catchy phrase the marketing department devised. These services require a card you plug into your laptop, just like Wi-Fi once did. And just like Wi-Fi, some new laptops have mobile broadband support built in, but since each carrier uses a different protocol, unlike Wi-Fi service providers, buying a built in model will lock you into one service.

While the encryption isn't great on these mobile broadband systems, according to this newsletter's official security consultant, Jesper Jurcinoks of NetVigilance, it's way better than unencrypted Wi-Fi and even low-end Wired Equivalent Privacy (WEP) Wi-Fi. Forcing a cellular data card into promiscuous mode would require great effort and hardware modifications by the hacker.