Step 5. Filter MAC addresses
Whether you have a laptop or a Wi-Fi enabled mobile phone, all your wireless devices have a unique MAC address (this has nothing to do with an Apple Mac) just like every computer connected to the Internet has a unique IP address. For an added layer of protection, you can add the MAC addresses of all your devices to your wireless router’s settings so that only the specified devices can connect to your Wi-Fi network.
MAC addresses are hard-coded into your networking equipment, so one address will only let that one device on the network. It is, unfortunately, possible to spoof a MAC address*, but an attacker must first know one of the MAC addresses of the computers that are connected to your Wireless network before he can attempt spoofing.
To enable MAC address filtering, first make a list of all your hardware devices that you want to connect to your wireless network**. Find their MAC addresses, and then add them to the MAC address filtering in your router’s administrative settings. You can find the MAC address for your computers by opening Command Prompt and typing in “ipconfig /all”, which will show your MAC address beside the name “Physical Address”. You can find the MAC addresses of Wireless mobile phones and other portable devices under their network settings, though this will vary for each device.
[*] What do the bad guys use - Someone can change the MAC address of his or her own computer and can easily connect to your network since your network allows connection from devices that have that particular MAC address. Anyone can determine the MAC address of your device wireless using a sniffing tool like Nmap and he can then change the MAC address of his own computer using another free tool like MAC Shift.
Step 6. Reduce the Range of the Wireless Signal
If your wireless router has a high range but you are staying in a small studio apartment, you can consider decreasing the signal range by either changing the mode of your router to 802.11g (instead of 802.11n or 802.11b) or use a different wireless channel.
You can also try placing the router under the bed, inside a shoe box or wrap a foil around the router antennas so that you can somewhat restrict the direction of signals.
Apply the Anti-Wi-Fi Paint – Researchers have developed a special Wi-Fi blocking paint that can help you stop neighbors from accessing your home network without you having to set up encryption at the router level. The paint contains chemicals that blocks radio signals by absorbing them. “By coating an entire room, Wi-Fi signals can’t get in and, crucially, can’t get out.”
Step 7. Upgrade your Router’s firmware
You should check the manufacturer’s site occasionally to make sure that your router is running the latest firmware. You can find the existing firmware version of your router using from the router’s dashboard at 192.168.*.
Connect to your Secure Wireless Network
To conclude, MAC Address filtering with WPA2 (AES) encryption (and a really complex passphrase) is probably the best way to secure your wireless network.
Once you have enabled the various security settings in your wireless router, you need to add the new settings to your computers and other wireless devices so that they all can connect to the Wi-Fi network. You can select to have your computer automatically connect to this network, so you won’t have to enter the SSID, passphrase and other information every time you connect to the Internet.
Your wireless network will now be a lot more secure and intruders may have a tough time intercepting your Wi-Fi signals.
Who is Connected to your Wireless Network
If you are worried that an outsider may be connecting to the Internet using your Wireless network, try AirSnare – it’s a free utility that will look for unexpected MAC addresses on your Wireless network as well as to DHCP requests. Another option is that you open your router’s administration page (using the 192.168.* address) and look for the DHCP Clients Table (it’s under Status > Local Network on Linksys routers). Here you will see a list of all computers and wireless devices that are connected to your home network.
*It is also a good idea to turn off the router completely when you are not planning to use the computer for a longer period (like when you are out shopping). You save on electricity and the door remains 100% shut for wireless piggybackers.
**If you ever want to let a new device connect to your network, you will have to find its MAC address and add it to your router. If you simple want to let a friend connect to your wireless network one time, you can remove his MAC address from the router settings when he or she leaves your place.
