GSM: Security
equipment identity checking
n Equipment Identity Register (EIR) maintains database related
to mobile equipment (hardware) identified by International
Mobile Equipment Identity (IMEI)
n IMEI consists of Type Approval Code (granted when mobile
station type passes type approval testing to ensure mobile
station behaves properly), Final Assembly Code (indicating
manufacturing plant), and the equipment serial number
n EIR stores three lists of IMEIs
white list contains ranges of IMEIs of type approved mobile
stations, maintained by MoU
black list contains IMEIs which are stolen or malfunctioning,
and are subsequently barred
gray list contains IMEIs which should be supervised for possible
malfunctions