Wireless networking allows you to connect to a network and often the Internet without using a cable. As more people purchase laptops, PDAs, and other mobile devices, wireless network access has become increasingly popular and convenient. Wireless access points must be set up properly to provide sufficient security. However, most wireless access points are set up in a manner that is extremely insecure. Without the proper precautions, wireless networking can place your privacy, your data, and your computer at significant risk. 
When connected to an insecure wireless network, anyone within range of your computer and using the right tools can easily capture your traffic as it is transmitted across the network. This type of ‘‘listening in,’’ known as sniffing, can be done with a laptop (or PDA), a wireless card, and some freely available software and is very difficult to detect.
Attackers may also use your connection for their own nefarious purposes. This could include anything from illegally downloading copyrighted files to posting child pornography on the Internet.
Follow these tips to use someone else’s wireless connection safely:
• Avoid sending sensitive information over a wireless network.
• Encrypt your traffic.
• Provide sensitive information only to ‘‘secure’’ sites, i.e., sites that display https:// in the address bar and a padlock.
• Use virtual private networking (VPN) to encrypt all network traffic to and from your computer. If you have VPN access through your company or school, use it whenever you access a wireless network.
If you have set up your own wireless router or access point, you are responsible for ensuring that you have configured the router settings to provide sufficient security. Ensure that you have configured the following:
• Disable set service identifier (SSID) broadcasting. To make it easier to connect to a wireless network, access points broadcast the name of their network so that mobile devices can easily detect them. Disabling SSID broadcasting makes your wireless network ‘‘invisible’’ unless you already know the name of the network.
• Enable media access control (MAC) address filtering. Each wireless network card has a unique identification number known as a MAC address. By allowing only your network cards to access your wireless network, you can prevent other people from using your Internet connection without your permission.
• Enable Wi-Fi protection access (WPA) encryption. Enabling encryption on your access point serves two purposes. First, it prevents attackers from sniffing your traffic, which prevents them from watching what you are doing online. Second, it forces anyone attempting to access your wireless network to enter a password to gain access to your network. Wireless routers provide a number of other ways to ensure only permitted computers are accessing the network.