IMEI is the acronym for International Mobile Station Equipment Identity used to detect signals from satellite phones. Any 3GPP and iDEN mobile phone users can check their IMEI by dialing *#06# on the dial pad. Sometimes, it is also printed inside the phone’s battery or simply displayed on screen.
IMEI is a very important tool in identifying stolen phones. GSM networks make use of it to spot valid devices. For example, when a mobile phone is snatched, the owner can call to his network provider and report the event. He can instruct them to blacklist the phone using its IMEI so that the thief will be barred from using it. Blacklisting via IMEI renders the phone useless. It does not matter even if the new holder would change its SIM card. The transmission can still trace the EMEI stored on the SIM card, which is transferable to any handset.
IMEIs may be unlisted. It depends on where the mobile user is located. This process allows the users to activate certain passwords at the time the blacklisting was applied so the phone can never be used again. In satellite phones, EMEI numbers serve as transceiver. Since satellite phones do not have SIM cards, the modem relies purely on the EMEI number for identification. EMEI numbers can also tell the phone’s manufacturer, model type, and the country and date by which it has been approved. Even so, IMEI should not be mistaken to have permanent relations with the subscriber. While it is only used for identification it cannot be used at any other advantage such as revealing the identity of the thief.
The EMEI blocking system has already been adopted in many countries to help innocent victims. In United Kingdom they have incorporated an IMEI law under their Mobile Telephones Re-Programming Act.