When you miss a call on your cellphone from a number that you don't recognize, what do you do? Well, apparently, if you're like most people, you just call it back.
This seems to be the basis for a new scam that one of our wholesale customers was trying to run recently. It was a brand new customer, and all they were interested in were CLI routes to many countries in the Middle East. The price was secondary, which is always suspicious.

The scam works like this: the customer finds huge lists of cellphone numbers, then sets up an auto dialer which rings the phone once, then disconnects. As a caller ID, they pass a shared revenue number in a country like UK or Estonia (in this case it was Bulgaria), which they own. Now if they make 100000 such calls, and only 5% of the caller call back the number that shows up in their display, and they make $1 for each inbound call to this number, you get the idea...

While this might be completely legal, it is deceiving for the thousands of innocent victims who end up with a charge for a $5 or $10 international call on their phone bill. It is also prohibited in most of our vendor contracts to use voice termination as pure method of signaling information, without the intention of establishing a bona fide voice call. Within hours we get complaints from the terminating networks in the foreign countries to remove such traffic. We therefore ask our wholesale customers not to send this kind of traffic to us for termination.