The prosperity of any organization depends on how well it communicates with its clients or how incessantly it caters to their needs or attends troubleshooting. As a catalyst to this process came the concept of PBX or PRIVATE BRANCH EXCHANGE. This allows one dialing number to be connected to several telephone units. In this way the calls of several callers on a single number can be attended.

Also another catalyst would be the VOIP or VOICE over INTERNET PROTOCOL. VOIP is a methodology and group of technologies for the delivery of voice communications and multimedia sessions over Internet Protocol (IP) networks, such as the Internet.

As much as these developments have brought in simplicity and ease to the process of client handling, they have also at times incurred huge losses to the organization in the light of the various malpractices or nefarious activities that have recently cropped up. One such practice happens to be that of INTERNATIONAL REVENUE SHARE FRAUD, that has come to the forefront and grabbed a lot of eyeballs for the sheer measure of currency that it has generated by this type of a scam.

There happens to be a very simple modus operandi involved with IRSF.

Firstly the hacker involved in IRSF needs to find a PBX system to hack into. This can be easily done by going through a list of such numbers and tracking down to the most vulnerable ones.
Secondly he has to choose IRS destination maybe in some foreign country where calls are charged with exorbitantly high prices.
Join hands with such IPRN providers for increasing traffic and in turn share profits.
Continue calls till the owner happens to be unaware of the entire scam that is continuing.