If you don't have a broadband connection, you should obviously need one of those dialers to connect to your Internet Service Provider through the analogue telephone line or ISDN. Many Internet Service Providers provide their users with the installation CDs, which make the process of setting up an Internet connection through the phone line easy and comfortable. One should either create an entry in the dialer built into the operating system your computer runs on, or through the installation of a different dialer (big ISPs have their own software, like AOL for example).
Today the term "dialers" is used to denote the specific dialers which are distributed with the obviously fraudulent intent. They start themselves without users consent thus resulting in huge bills for the services the user might even never desire.
As dialers are absolutely necessary to set up a connection to the Internet (if you run a non-broadband connection), lots of users use them. But certain dialers, like Trojan win32 dialer, are specially designed to call the premium-rate numbers. The security holes of the system are scanned and if there is any vulnerability, the dialer installs itself and then makes the computer call the special number instead of that provided by an ISP, earning some bucks for their developers. However, some of the dialers do inform the user of what they are doing, promising access to additional content instead (this may include music, video, pornography, wares etc.)
It is relatively easy to set up such a service. A few thousand dollars for the telecommunicating equipment should be usually enough and the operator typically pockets up to 90% of the premium-rate call cost. In the USA these premium-rate numbers usually start at 900 and they are a very popular method to pay for the services. However the users may have to pay 4 USD or even more per minute if they use such dialers. Because modems are relatively slow, the user should stay at least 10-15 minutes on the line to download everything he needs, so you can imagine the profits of the operators easily without our help.
If you use broadband connection and don't have a modem connected to your computer, you should not worry about those nasty malicious dialers, which can be identified through the following features:
- you are exposed to download popups when visiting a website.
- the hint about the price is small and hard to see (if there is any after all).
- no matter whether you have given your consent or not, the download starts.
- the dialer automatically sets itself as the default connection.
- the unwanted connections are initiated by the dialer itself without your interaction.
- you are never informed of the price during the connection.
It is sometimes very difficult to remove dialers, even with the help of the specific software. These applications are smart and are able to mask their installation files and reinstall themselves all the time even after they have been deleted. If you connect to the Internet through an analogue phone line, make sure it dials the right number so that you won't be surprised to find a 4-digits phone bill in your mailbox next month.