13-Jun-2016 08:51

Change of IMEI to Prevent the SIM-block


There are many parameters that mobile carriers use to keep track of voice traffic terminators and block their SIM-cards. One of them is the IMEI, which is a unique number that is assigned to each telephone set for its international identity. Antifraud systems can easily track gateways if all SIM-cards use the same IMEI, provided in the equipment by default. The indicator for the carriers is the activity that is unusual for one subscriber since a person cannot use several SIM-cards in one telephone and make a few calls at the same time, with the appropriate IMEI assigned to mobile devices that support 2 or more SIM cards.

Using the SIM-bank does not make it much better. Most models are equipped with the "Random IMEI" function, that is, a random number is determined for each card. However, with intensive GSM termination, a SIM-card can be assigned to different IMEI almost every day since the cards are unloaded and loaded again. Thus, the operator realizes that one cannot often change phone numbers and takes it as a sign of traffic termination.

To prevent blocking of SIM-cards, use GoAntiFraud. Efficient tools for the simulation of human behavior on the GSM networks will allow you to significantly increase your revenues.

Generation of IMEI

As you would expect, the terminators are always looking for solutions to problems related to IMEI. Many people use the terminal software to change the identification numbers, as well as software to generate IMEI. They create unique numbers that meet certain standards set by the competent authorities (such as BABT, etc.). A generated IMEI must meet the following criteria:

  • It should include 15 digits (14 main ones + the check one);
  • It should contain the check digit at the end of number calculated by the Loon algorithm (until 2003 it was equal to 0);
  • The number should be displayed in the AA-BBBBBB-CCCCCC-D format;
  • The first 6 digits represent the RBI official code and the model of a mobile device;
  • The 7th and 8th digits indicate the origin of the phone (there are special codes for various countries);
  • The last 6 digits are the serial number.

However, the IMEI generation does not solve the problem entirely, as in this case a terminator uses non-existent identification numbers. Sooner or later, the carrier notices it and blocks SIM-cards, to which they are assigned. Moreover, the problem is not going away with the assignment of different IMEI to the same card.

GoAntiFraud provides the GSM traffic terminators with the convenient and reliable solution to prevent the SIM-block. We have our own IMEI database, which includes real identification numbers corresponding to the second-hand phones. Using our service, you can assign an IMEI to each SIM-card, which will not change when it is unloading or loading. This will simulate the behavior of a person, creating the impression that SIM-card is always on the same phone.

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