What you don't know can hurt you. Next time you connect to one of them, be very observant you're connecting to a legitimate one and not an evil twin.
What is an evil twin? They are fake Internet gateways posing as a legitimate wifi hotspots. Supposing you visit the local Internet cafe who has a paid hotspot. You boot up your notebook computer, your wifi connection software seeks out available networks and gives you an option of two (maybe more) networks you can get online with. One of them is from the Internet cafe, but wait. You see one that says "Free Wifi courtesy of Wifi Hotspots Nation" or whatever. Everyone loves a deal, who do you get on with? If you chose the one from Wifi Hotspots Nation, then you may have connected to the Internet on the Evil Twin's network. Note Wifi Hotspots Nation is a fictitious name I created but that is the irony. An evil twin usually operates using a fictitious or deceptive name that's always changing. Since there is no authority governing the names of wifi hotspots, there is nowhere you go to check up on their legitimacy.
Wifi hotspots networks are like doors. In one place (hotspot) you can have many doors. Through one door, you can enter a solid brick room and do what you like since no one is watching you. Through another, you enter into a room with a two-way mirror where someone is watching and recording your activity quietly without you knowing. Both doors are marked in a way you think you're going to the same place but in reality you're not. One of them is really an evil twin; A wolf in sheep's clothing.
Enough about doors and sheep, what does this mean to you? I think you're smart enough to figure it out by now. By connecting to the evil twin, it's easy for the people running it to capture any information you're entering onto websites or even snoop around in your computer and private files. And while they're there, why not drop some kind of malicious software that'll run in the background you'll never even know was there. Who knows that they do.
Aren't these fake wifi hotspots easy to detect? If you're the owner of the legitimate wifi hotspot, you can tell which network belongs to you or not but not to the average user because they aren't visible and it's very easy to setup wifi hotspots. You and I can do it. There are no alerts and sadly, often the people who work at these hotspots aren't knowledgeable enough to warn you either. The person sitting next to you whom you think is doing work online could be operating an evil twin, or they could be one of those duped by one.
What do you do? In an ideal world, don't connect to wifi hotspots networks or don't get on a public wifi at all. If you absolutely must get an Internet fix, don't conduct online transactions like buying stuff, logging into your online bank or any place you'd be asked for sensitive information.
Next, disable all kinds of file or print sharing. If using WindowsXP operating system, go to Start, Control Panel and then Network Connections. Right click on the Internet connection or the Network connection and select Properties. In the General tab, locate and uncheck File and Printer Sharing. Click apply.
If you set up your notebook computer to connect automatically whenever a network is found, you'd want to disable that or change it to manual connection.
Make sure your firewall is turned on and any antivirus software is up to date.
As a good practice, if you have any sensitive files or information on your computer, consider putting them into one or several dedicated folders and then securing those folders by making them private. In WindowsXP, select the folder in question, right click on it and select properties. In the sharing tab, locate and check "Make this folder private".
These suggestions aren't fool proof but can help put stumbling blocks in an offender's path. The best protection is still being knowlegeable about wifi hotspots networks and not to connect to a suspicious network. And if you're in doubt, don't connect at all.
Sidenote: Similarly, if your neighbour offers their wifi network for you to use, make sure this is someone whom you trust.
About the Author
Lynn Chan simplifies computing and computer care issues for new notebook computer owners. Start protecting your investment, with a free tutorial available at http://www.notebook-computer-infocenter.com/5days-to-a-healthier-notebook.html