Do I need to be concerned about Wi-Fi security in my home network? I have a firewall.

Yes, absolutely! While you should always use both a personal software firewall, and a hardware-based router firewall on your home network, these don't substitute for Wi-Fi security measures. You also need Wi-Fi protection because data being sent over the airwaves is there for anyone nearby to capture, regardless of whether you are using a firewall. A firewall only protects you against attacks coming over the Internet into your local network.

While home Wi-Fi networks can free you to work (or play!) anywhere in the house, too many users just plug them in, neglecting to turn on security features or set passwords. Yes, this is a chore, but the latest routers make the process relatively simple, and the alternative is allowing freeloaders on your network (at best), or malicious hackers bent on stealing your data (at worst).

Here are three simple things you can do to lock up your Wi-Fi net:

First, change the default router password provided by the manufacturer. That will ensure no one else can go back in and change the security settings you make next. Second, turn off the broadcasting of your SSID, and change the SSID to something non-obvious (i.e. NOT "Wireless" or "Netgear"). Finally, turn on WPA/WPA2 encryption if you have it, WEP if you don't. This will require entering a password on each of your client devices as well, but once stored, you won't have to enter it again.

One more step you can take if you want to tighten things up even further is to limit wireless access to devices with specific MAC addresses. Not all routers have this feature, but most do.