The GSMA maintains a unique system known as the IMEI Database (IMEI DB) to help protect against such theft and its consequences to both users and operators.
Centralised Database of Information
The IMEI DB is a centralised global database containing basic information on serial number (IMEI) ranges of millions of GSM and 3G devices that are in use across the world. Access to the IMEI DB is provided to GSMA members and qualified industry parties such as manufacturers.
Network operators can use the information in the IMEI DB to determine what types of devices are being used by their customers, and what features they support, so that they can offer and support the latest services to these customers through their networks.
The IMEI DB also supports a ‘black list’ of IMEIs that are associated with devices that should be denied service on mobile networks because they have been reported as lost, stolen, faulty or otherwise unsuitable for use.
Because it is a central system, the IMEI DB allows network operators to share their individual black lists so that devices denied service (blacklisted) by one network will not work on other networks even if the SIM card in the device is changed.
Network operators who deploy Equipment Identity Register (EIR) in their networks use them to keep their own lists of blacklisted lost or stolen phones. Operators’ EIRs automatically connect to the IMEI DB system to share their latest lists of blacklisted devices with other operators.
Every day since 1996, the IMEI DB has taken all the black lists from different operators around the world and added them together into one global black list. When an EIR subsequently connects to the IMEI DB, it downloads the latest global black list (or a national or regional subset of the global list) for its own use. By loading the IMEI DB black list onto the local EIR, all handsets reported as stolen on other connected networks up to the previous day are now also blocked on that network.
Operators Around the World
Many mobile network operators have responded to the problem of handset theft by deploying EIRs in their networks and connecting them to the IMEI DB.