When you install your router for the first time you can select for example WEP to encrypt the signal
You can also set up WEP and other security options post-install via the router's built-in setup utility.
In addition to WEP/WAP encryption, here's a bit more on security-related wireless settings from an earlier post of mine. The discussion was concerning a Linksys router, but the basic ideas are not Linksys-specific:
Most of the configuration is done in the router's setup utility, so open your web browser and point it to
http://192.168.1.1, which is the default IP for that model of router.
Speaking of "defaults", it is never a good idea to leave settings such as the IP address, device name, aministrative password, SSID, etc. of a wireless router or other wireless access device at their defaults. The default settings for different manufacturer's devices are well known, and getting just one of those pieces of information can give an attacker a lot to go on.
For instance: if I wander around downtown San Francisco with my laptop, I can usually pick up at least 7 wireless networks in any given place. Most of the time, 3 or so of those networks will be broadcasting the default SSID "Linksys". Just from seeing that, I can be 99% sure that at least one of those networks:
- Is not using WEP encryption.
- Is using the Linksys default IP of 192.168.1.1 for the router.
- Is using the Linksys default password "admin" for the router.
- Is not using MAC address filtering.
- Is using the router as the DHCP server for the network.
- May likely have remote administration enabled on the router.
Bingo! Set my wireless for DHCP, connect to that network, and at the
very least I now have free Internet access. If I felt like being nasty, I could log into their router's setup page and reconfigure it to deny access to anyone but me.
So:
1. In the router's Basic Setup page:
- change the router name to something unique and/or obscure.
- change the router's internal (LAN-side) IP to something non-standard, keeping in mind that the IP address you choose still need to be within one of the ranges of private, non-routeable address ranges (the 192.168. or 10. ranges for example). If you understand the consequesnces, you can also change the subnet mask.
- Disable the router's DHCP server; manually assign the IP info on each computer on your network instead. If you want or need to use DHCP, you can limit the DHCP scope (the "Maximum number of DHCP users" setting) to a number equal to the number of computers on your LAN. That way someone else can't just join your network and automatically get handed an IP.
2. In the "Wireless" setup tab:
- Change the default SSID to something meaningful to you, but something that does not give anyone else any hints about your network. For example, using your name or your residence's street address as the SSID is not what you'd call a bright idea.
- Disable SSID broadcasting so that your SSID is not visible to the outside world.
3. The Wireless Mac Filter page under the Wireless tab:
Every network device has a unique (12 hexidecimal digit) identifier called the Media Access Control address. In the filter page, you can permit or deny computers permission to connect to your wireless network based on their individual MAC addresses. If you know that your two laptops should be the only computers connecting to your network, you would choose the "Permit only" filter option and then enter the MAC address of each laptop in the filter list. In Windows 2000 and XP, you can find the MAC address of a computer's network card by opening a DOS box and typing the following command at the prompt: ipconfig /all. For Win 9x/ME, the command is: winipcfg. The MAC address will be listed on the "Physical Address" line in the resulting output of the ipconfig command.
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