Let's start with the basics. Most of the wireless gateways/ routers have the encryption disabled by default. Make sure to enable either WEP (Wired Equivalent Privacy) or WPA (WiFi Protected Access) wireless encryption.Using WPA is recommended because it's more secure, but is sometimes a bit harder to set up than WEP. If you want your wireless network to really be secure, WPA is the preferred method.
NOTE: We do not recommend disabling Encryption. Make sure you are using WEP or WPA for your wireless network.
Change Your Gateway/Router SSID name
(Wireless Network Name) refers to the name of your wireless connection that you see on Available Wireless Connections while trying to connect from your computer. Changing the name itself doesn't protect your completely but it may discourage someone from hacking your network. Don't use something like your name, address, birth date, or other things that make it easy for someone to identify you. If you leave it '2wire2701' (or whatever the default is on your gateway/router), your computer automatically connects to every other network it encounters with the same name, and not every wireless network is a good and secure thing to connect to. Check the SSID on your AT&T provided gateway/router.
Do Not Disable SSID Broadcast
Do not disable the SSID Broadcast feature of your gateway/router. Hackers have sophisticated tools that can easily get information, so disabling SSID Broadcast won't improve your security. If you disable SSID Broadcast, it makes it difficult to connect other computers and devices, like wireless gaming consoles, printers etc., to your network. Additionally, if you have SSID Broadcast disabled, hackers can use technology to pretend to be your gateway/router and gain access to your computer.
Enable MAC Address Filtering
If you want to go one step further in locking down your network there is another step that only allows access to trusted devices. You can enable MAC Address (Media Access Control) filtering on your gateway/router. The MAC address is a unique identifier attached to the network adapter on a device like your notebook computer or wireless gaming console. If you enable Mac Address filtering on your network, you need to find and enter into your gateway/router the 12-character MAC address of every system that connects to the network. This can be time consuming to set up, especially if you have a lot of wireless devices and if there are a lot of different users on your network.