Method of controlling access to a radiotelephone system

摘要

A radiotelephone system (100) includes a radiotelephone (103) having a subscription lock and a removable subscriber identification module (SIM) card (105) containing an international mobile subscriber identification (IMSI). The subscriber lock is used to restrict registration into the radiotelephone system (100) to only those radiotelephones which contain a SIM card which has an IMSI which falls within a range of valid IMSIs programmed into the radiotelephone or the user has entered a subsidy flag personal identification number (PIN) for permanently disabling the need for a valid IMSI.