code 40 this data includes an u201c operator determined barring u201d odb flag 42 the odb flag 42 can indicate that a call initiated using a particular imsi 40 should not be connected a provider may set an odb flag 42 if a handset is reported stolen or if a customer has failed to pay a bill the database 24 also stores an msisdn 41 code by storing an msisdn code 41 within a predefined range prior to handset programming the msisdn code 41 acts as a flag warning switch software of uninitialized handset use that is when the msc software 22 examines a copy of the subscriber profile data in the vlr 23 which is sent by the hlr 24 for the msisdn 41 corresponding to an imsi 40 that initiated a call the msc software 22 can determine whether the handset producing the call has been programmed referring now to fig4 the msc software 22 identifies imsi codes of unauthorized handsets i e handsets requiring programming the msc software searches 44 the vlr 23 for a table entry corresponding to a received imsi by examining the odb flag 46 the msc software can determine if the handset initiating the call has been barred if not the msc software 22 can route the call normally if the odb flag has been set however the msc software 22 can determine if the.