Wireless networks using 802.11 have made it simple to connect multiple devices to your home network.This can also make your data availiable anywhere, even outside your home.To set this up all you need is a broadband connection connected to a wireless router or a WAP Wireless Access Point. Your home computers should have wireless access cards installed or if your using a laptop a PCMCIA wireless card. Intel Centrino is great for wireless, I personally use it. I like the fact that I did not have to purchase additional hardware.
When you set up your wireless router or WAP your signal is broadcast. This broadcast usually goes further than your home or business. People like to drive around finding unsecured wireless access points. This is known as Wardriving, some hackers even mark spots on the sidewalk to let other hackers know your home or business is offering free Internet service, or worse yet access to your data.This is not to scare you but make you aware.
Diasble broadcasting so people cannot you your wireless network.
Your routers come with pre-configured system ID's its called a SSID or Service Set Identifier, its very simple to locate this information on the Internet for default SSID's I recommend changing this to something hard to guess. Use alphanumeric's to make it even harder to guess.
Use encryption to protect your network. WEP or Wireless Encryption Protocol is not secure, I have cracked my own network with a Linux machine running Kismet. WEP's keylength is only 40 bits, once you collect enough data from packets its only a matter of time for a determined cracker.Instead use WPA which is WI-Fi protected access. This is more secure.
Configure your router to block incoming outgoing traffic you do not use. Consider blocking Port 23 Telnet and Even FTP.
Router manafacturers have default passwords which I find many home users do not change. CHANGE THEM!
Invest in a software firewall and keep your system up to date. In the month of October 2005 there have been several security flaws listed by Microsoft. Keep Informed.