One of the earliest forms of WLAN protection was MAC Address Filtering. The term "MAC" is short for Media Access Control. Every hardware device on an 802 network (wired or wireless) has a unique MAC address. This is not the same as the IP address; the MAC address can be thought of as "stamped" onto that network device. It's much like the VIN number found on an American automobile. To start, open a Command Prompt window as shown below.
In the Command Prompt window, type in the command ipconfig /all, the "Physical Address" listed is the MAC address for the Ethernet adapter in use.
Most WAPs will let you enter a list of MAC addresses of "approved" wireless devices that will be allowed to use the WAP's services and connect via a wireless connection. (Some routers also have a list for wired devices kept either separately or in combination with the wireless list.) Using "MAC address filtering," as it is called, helps to keep people from using your network, but it does nothing to keep them from capturing the traffic generated by it. (Hence, encryption is still needed.) Also, MAC addresses are not secure; programs exist that will allow the MAC address of a wireless card to be temporarily changed to mimic any MAC address - including one in your approved list. This is just one more tool to help keep unwanted wireless devices off your network. To set up MAC Address Filtering on the WRT624, go to the Advanced Wireless Settings page using the left menu. Then click on the Setup Access List button.
Check the "Turn Access Control On" check box and hit the Apply button.
This will refresh the page with a list of wireless adapters currently in range. Most WAPs start with a list of devices currently connected in order to make it easy to set up the initial list.
Select the radio button next to the one(s) you wish to include. You can also manually enter the MAC address (found using the ipconfig /all command in the Command Prompt window).
If your ISP supplied your router, it will likely include wireless networking built in. By default, it is usually enabled and either not secured or secured only with the factory default settings. If this is the case, and you aren't going to use the wireless capabilities, you should disable them completely - unless you want to provide free Internet service to your neighbors (which likely violates the Terms of Service with your ISP). If you don't, they can use your wireless connection freely for any purpose they choose such as illegal file downloading and sharing. This is especially prevalent in townhomes and apartment buildings. If the RIAA lodges a complaint about illegal file sharing, it will be traced to the IP in use by your account. Your ISP will generally terminate your service permanently without question upon receipt of the complaint even if you weren't aware of the activities taking place. Even if they aren't doing anything illegal, they may be doing things that use lot's of your network's bandwidth, and it's quite possible they will be able to see and inspect the devices on your network. Let's avoid that.
If you aren't going to use the wireless capabilities, the best thing to do is to shut them off. (If you are going to use wireless networking, you want to configure your network to use wireless encryption and perhaps take other security precautions.) How the wireless is shut off varies between different makes and models of routers. You will need to consult the user's guide for your router. What you are looking for is something that disables wireless networking or disables the wireless radio. In the example below, the check box is simply labeled, "Enable Wireless Router Radio." Take care not to confuse this with a setting to Enable the SSID broadcast. These two settings are not the same and disabling the SSID broadcast does not disable wireless networking.
If you've ventured this far, congratulations! You've reached the end of configuring the wireless network medium. Now it's time to move on to Configuring Your Network. Having gone through this section, you have a leg up on that task because we had to do a good portion of it in order to configure the radio medium. Don't worry if you don't need to do some of the tasks in that section because they were already done when you went through this section.