Internet Fraud - International Modem Dialing

International Modem Dialing

Customers of dial-up Internet service providers, such as AOL, use a modem to dial a local telephone number in order to connect to the Internet. Some web sites, typically containing adult content, trick consumers into paying to view content on their web site by convincing them to unwittingly make international telephone calls with their modem.

Often these sites claim to be free, and advertise that no credit card is needed to view the site. They prompt the user to download a "viewer" or "dialer" program to allow them to view the content. Once the program is downloaded, it disconnects the computer from the victim's usual Internet service provider and dials an international long-distance or premium-rate number, charging unexpectedly high rates to the victim's long-distance phone bill.

While one can usually request that their phone company block their line from making international calls in order to prevent this scam, there are loopholes that the scammers can exploit. In the United States and Canada, phone numbers are assigned Country Code "1" and a three-digit "area code" under the North American Numbering Plan (NANP). However, Bermuda and 16 Caribbean countries are also part of the NANP, so a phone number that has the same appearance as a domestic number may actually be an expensive overseas call. Scammers can also use a "Carrier Access Code" to override the user's default choice of long-distance company; this works around the international-calling block that the customer placed with that company.