Recently, I noticed some strangeness on my home wireless network. Sometimes the speed would be slower than normal, I couldn't print to my printer, and some of my more advanced router settings (for port forwarding, firewall, etc.) would seem to be "lost".
As it turns out, my laptop was attaching to my next-door-neighbor's network. When I went to help him out, we saw that he could see HIS neighbor's network! Both had failed to do some basic wireless security.
Failing to secure your network could have several negative consequences. First, it's your network. You don't want freeloaders using your bandwidth. You also don't want them seeing your shared folders, using your printer, and downloading questionable or illegal content from your IP address!
So here we go with WiFi 101: security settings.
It stands for service set identifier, but think of it as your network name. Wireless routers, by default, broadcast their network name. Any device that comes in range can see the network and attempt to connect. Step 1 in securing your network? Stop broadcasting your SSID! Log onto your router (the exact steps vary router by router, but usually you can do this by browsing to http://192.168.0.1 or http://192.168.1.1, and entering a username and password: try 'admin' for both).
Look for a checkbox or radio button that says "Wireless SSID broadcast", and disable it. This means only computers that already know the network name, can find the network.
While we're here, change the default router password and username to something you can remember. On most Linksys routers, you can do this by following the 'Administration' link.
Wired Equivalent Privacy: it's an encryption scheme, to secure the traffic between your wireless computer and your router. Use it! WEP works by generating a set of keys (passwords), based on a seed phrase. You can generate 64-bit or 128-bit keys. Write down the keys, because your laptop will need them in order to talk to the router once WEP is enabled.
Every Ethernet card has a unique number, called a "MAC (Media Access Control) address". Think of it as digital serial number for your network card. On Windows machines, if you go to a command prompt (DOS window), and type
ipconfig /all , you can see your MAC address. Look for "Physical Address", it will be a series of 2-digit numbers separated by dashes or colons. Careful! You might have two, one for your "built-in" network card, and another for your wireless card.
Routers can be configured to only talk to specific MAC addresses. I recommend doing this as well. Even if someone discovers your SSID and WEP keys (you wrote them on a sticky and stuck it on your monitor) the router can refuse them because they aren't "on the list".
Once your router is configured to
- Disable SSID broadcast
- Use WEP encryption
- Use MAC filtering
then it's time to configure your laptops and wireless devices to see the router.
For Windows machines, you can use the "Wireless Network Setup wizard" in the control panel. You'll enter the SSID name, the WEP key, and so on.
WiFi is definitely convenient, but don't neglect security! Protect your network and yourself by configuring your router's security settings.