Telecommunications system

Abstract

In a telecommunications system such as a global mobile telephone network in which each subscriber unit includes a Subscriber Identity Module (SIM card), each SIM card has fixed memory locations, to which data can be addressed over the air. Some of the locations can not be overwritten from the subscriber unit but can be accessed therefrom on the entry of short simple codes, each associated with one of the locations. Further fixed memory locations can be read over the air only when the subscriber enters a personal identification number. Locking control files are used to control read/write access to the locations respectively.

1 - 29 . (canceled) 
     
     
         30 . A SIM card for controlling a subscriber unit in a telecommunications system comprising at least one host station, the SIM card being releasably connectable to a transceiver of the subscriber unit and comprising:
 a multiplicity of memory locations responsive to the detection of a SMS message transmitted from the at least one host station to store the SMS message in a selected one of the memory locations, the SIM card distinguishing a SMS message from other message formats used in the system, the SMS message coded in a specific format comprising a command;   the SIM card capable of decoding and storing a SMS message coded in the specific format in a selected memory location, and operable in response to a decoded SMS message to initiate an action to be taken by the subscriber unit to manipulate data.   
     
     
         31 . The SIM card of  claim 30 , wherein the SIM card transmits requested information in a SMS message to the subscriber unit. 
     
     
         32 . The SIM card of  claim 30 , wherein the SIM card distinguishes between a SMS message comprising information to be stored, a request for information stored in the SIM card, and an instruction to execute a program. 
     
     
         33 . The SIM card of  claim 30 , wherein the SIM card responds to a personal identification number entered in the subscriber unit by a subscriber to render a secure memory location of the SIM card accessible to the request for information transmitted from the at least one host station. 
     
     
         34 . The SIM card of  claim 32 , wherein the SIM card responds to the instruction for executing a program stored in the SIM card. 
     
     
         35 . The SIM card of  claim 30 , wherein the SIM card includes a locking control for selectively protecting the memory locations from reading or overwriting by the subscriber unit or the at least one host station. 
     
     
         36 . The SIM card of  claim 30 , wherein each memory location is associated with a simple, short code and responsive to the entry of the relevant the short code to retrieve data from the memory location. 
     
     
         37 . The SIM card of  claim 30 , the SIM card including a directory structure within which files can be stored. 
     
     
         38 . The SIM card of  claim 30 , wherein the SIM card is in the form of an integrated circuit card. 
     
     
         39 . A method of operating a telecommunications system in which at least one host station is operable to transmit messages to a plurality of subscriber units, comprising the steps of:
 providing a multiplicity of memory locations in each the subscriber unit, the memory locations being disposed in a SIM card integrated circuit module removably connected to the subscriber unit;   transmitting from the at least one host station to at least one of the subscriber units a SMS message coded in a specific format distinguished from other message formats used in the system, the SMS message comprising a command;   receiving the SMS message at the at least one subscriber unit and rewriting the SMS message to the SIM card integrated circuit module thereof;   causing the SIM card integrated circuit module to distinguish the SMS message coded in the specific format from the other message formats;   decoding the SMS message coded in the specific format to produce a decoded message;   storing the decoded message in a selected the memory location;   reading the decoded message and, in response thereto, initiating an action to be taken by the at least one subscriber unit.   
     
     
         40 . The method of  claim 39 , further comprising the step of transmitting requested information as a SMS message coded in the specific format to the at least one subscriber unit. 
     
     
         41 . The method of  claim 40 , further comprising the step of:
 receiving the SMS message and presenting the information from the SMS message to a user of the at least one subscriber unit or transmitting the SMS message to the at least one host station.   
     
     
         42 . The method of  claim 40 , including the steps of:
 transmitting a further SMS message from the at least one host station to the at least one subscriber unit coded in the specific format and comprising information to be stored in the integrated circuit module or instructions to execute a program stored in the module; and   distinguishing between the SMS messages comprising information to be stored, a request for information, and an instruction.   
     
     
         43 . The method of  claim 39 , wherein the SMS message is coded in a secure format. 
     
     
         44 . The method of  claim 43 , wherein the secure format is in the form of an embedded command stream which comprises a data stream headed by a command. 
     
     
         45 . The method of  claim 39 , wherein the reading step comprises:
 detecting when the decoded SMS message comprises an attribute command identifying at least one of the memory locations which is to be locked or unlocked so as to render the at least one memory location accessible or inaccessible to the at least one host station or the subscriber unit; and   locking or unlocking the identified at least one memory location, thereby controlling access to the at least one memory location from the at least one host station or the subscriber unit.   
     
     
         46 . A telecommunications system where at least one host station operates to transmit messages to a plurality of subscriber cellular telephones, comprising:
 a multiplicity of memory locations in each subscriber cellular telephone, each memory location disposed in a removable integrated circuit module;   transmitting from the at least one host station to at least one subscriber cellular telephone a message coded in a specific format distinguished from other message formats used in the system, the message comprising a command transmitted over a message channel;   receiving the message at the at least one subscriber cellular telephone and rewriting the message to a memory in the integrated circuit module;   causing the integrated circuit module to distinguish the message coded in the specific format from the other message formats;   decoding the message to produce a decoded message;   storing the decoded message in a selected memory location; and   responding to the command by initiating a data manipulation operation in the subscriber cellular telephone.   
     
     
         47 . The method of  claim 46 , further comprising the step of transmitting the message as a SMS message coded in the specific format. 
     
     
         48 . (canceled) 
     
     
         49 . The method of  claim 47 , further comprising the steps of:
 transmitting a further SMS message from the at least one host station to the at least one subscriber cellular telephone coded in the specific format and comprising information to be stored in the integrated circuit module or instructions to execute a program stored in the module; and   distinguishing between a SMS messages comprising information to be stored, a request for information, and an instruction.   
     
     
         50 . The method of  claim 47 , further comprising the steps of:
 storing the SMS message coded in a secure format;   securing a memory location or stored data using a personal identification number; and   accessing a memory using a personal identification number entered on the cellular telephone.