When you connect to the internet using a public wireless connection (such as at a coffeeshop or airport), there are some basic security precautions you should take. If doesn’t matter whether the connection is free or paid-for — the fact that it’s publicly accessible is what makes it risky, because it’s very easy to eavesdrop on internet traffic on a public wireless network. That means anything that you type, including passwords or other sensitive data, is potentially available to anyone who wants it. Is there an evil-doer lurking near every public wireless connection? Unlikely (although the odds go way up in airports). But there might be, and it’s not hard to keep yourself safer.
Of course, the advice that follows assumes you’ve already taken all the basic security precautions you should ALWAYS use, no matter your location:
- make sure you are running modern, fully up-to-date anti-virus software
- use a good user account password (no real words; mix letters, both upper and lower case, as well as numbers)
- keep current on all Windows security updates
- be sure to use a firewall (Windows 7 and Vista have their firewalls turned on by default)
In addition to these base-level precautions, follow these simple guidelines when connected to (or even near) a public wireless connection:
- Turn off the wireless radio when you’re not using it. If you don’t actually want or need to be online, use this simple, foolproof protection — it saves battery life, too. Most laptops have a physical switch; if yours doesn’t or you can’t find it, right click on the wireless icon in the lower right hand corner of the screen and choose “disable.” The icon should now sport a red “X.” (Just remember what you’ve done when you later can’t connect, and reverse your actions to turn it back on!). If you can’t figure out which icon to use, go to Control Panel/Network Connections, and right-click on the correct icon there.
- Do not type any passwords unless the site you are on uses a secure connection that scrambles your password. The easiest way to tell is to look in the address bar: if the page address begins with “https” instead of just “http,” then it’s a secure connection. This isn’t a failsafe indicator, since with some effort it can be faked, but if there’s no “s” you can be sure it’s NOT secure.
- Avoid entering any sensitive personal information that you don’t have to. Can you safely access your bank account or make a purchase via PayPal? Well, probably reasonably safely, but there’s definitely a greater risk that your private information will be stolen on a public network. If you don’t absolutely need to do something that involves money or other valuable private information, consider waiting and doing it somewhere else.
- Turn off file sharing.In Windows 7 and Vista, this is easy. When you connect to the network, be sure to choose “Public Network” (but don’t select “Treat all future networks as public…” or you’ll be sorry).With a Windows XP computer, this is harder. By default some or all of your hard drive is wide open to any other computer connected to the same network. At home, file sharing can be a wonderful convenience, but on the road, you’re unlikely to need or want it. Turning it off (and then back on again) is really easy or somewhat annoying depending on your security software:
- If you have decent firewall software (either a commercial product or a good freeware firewall like Comodo), you can use that to prevent file sharing. A message from your firewall software should automatically pop up when you first connect to a new network. But it if does not, open your firewall software and tell it to treat the current network as “public” or “untrusted.” If you don’t have third-party firewall software, you should at least have the Windows firewall, which serves the same purpose. Go to Control Panel/Windows Firewall. Be sure that it is turned on, and set to “Don’t allow exceptions.”
- You can also just disable file sharing from within Windows. Go to Control Panel/Network Connections. There, right-click on the icon that represents your wireless connection, and choose “Properties.” Under the “General” tab of the resulting dialog box, there is a list of available services for that connection. Un-check “File and Printer Sharing for Windows” and press “OK.”
Using Wireless Technology Securely, a pdf docment from U.S. CERT, the federal government’s “computer emergency readiness team.” It was updated in 2008 but is still relevant. Information on public networks in particular begins on page 4.