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 method for operating a cellular telephone system facilitating communications amongst a multiplicity of subscriber units, comprising:
 a) during normal operation of the cellular telephone system, transmitting and receiving non-voice messages between the subscriber units;   b) during normal operation of the cellular telephone system, transmitting and receiving voice calls between the subscriber units;   c) when a modification of operation of the subscriber units is desired, sending out one of said non-voice messages which contains an embedded command; and   d) automatically executing said embedded commands, in at least some ones of said subscriber units;   wherein said action b is performed in dependence on the result of said action d.   
     
     
         31 - 47 . (canceled) 
     
     
         48 . The method of  claim 30 , wherein the non-voice message is either a first type of message which does not include an embedded executable command or a second type of message containing an embedded executable command for at least some part of a subscriber unit. 
     
     
         49 . The method of  claim 30 , wherein a subscriber unit is configured to determine whether the non-voice message is of a first type of message or a second type of message. 
     
     
         50 . The method of  claim 30 , wherein
 if the non-voice message is of a first type, a subscriber unit displays a non-voice message; and   if the non-voice message is of a second type, a subscriber unit automatically and without end user intervention executes the embedded command.   
     
     
         51 . The method of  claim 30 , wherein said embedded commands, when executed, can effect data stored by a subscriber unit. 
     
     
         52 . A method of communicating between a remote station and a cellular telephone capable of two-way voice communication, comprising the steps of:
 selectively transmitting from the remote station to the cellular telephone a first message type containing text to be displayed to an end user of the cellular telephone or a second message type containing a command;   distinguishing an incoming message as being either the first or second message type using the cellular telephone;   if the incoming message is of the first message type, displaying the incoming message on a display of the cellular telephone; and   if the incoming message is of the second message type, the cellular telephone automatically, in response to the command in the incoming message, undertaking appropriate processing.   
     
     
         53 . The method of  claim 52 , wherein the selectively transmitting is performed without requiring end user interaction. 
     
     
         54 . The method of  claim 52 , wherein the first and second message types are formatted using a common formatting method. 
     
     
         55 . The method of  claim 52 , wherein the message types are SMS messages and detecting an incoming communication as an incoming SMS message and passing the incoming SMS message to a coupled SIM card using the cellular telephone. 
     
     
         56 . The method of  claim 52 , wherein the message types are SMS messages processed as either an SMS command message or an SMS text message, wherein
 if the incoming SMS message is said first message type, it is an SMS text message, and a removably coupled SIM card causes at least a portion of the text contained in the incoming SMS text message to be displayed on a display associated with the cellular telephone.   
     
     
         57 . The method of  claim 52 , wherein the message types are SMS messages processed as either an SMS command message or an SMS text message, wherein
 if the incoming SMS message is said second message type, it is an SMS command message, and a removably coupled SIM card decodes the command contained in the SMS command message for acting upon.   
     
     
         58 . A system for communicating between a remote station and a cellular telephone that includes a memory having first and second sets of memory locations, a display, and one or more processors, comprising:
 the cellular telephone receiving from the remote station a message which can be of either a first message type containing text to be displayed to an end user of the cellular telephone, or a second message type containing a write command and associated write data to be written to the memory;   the one or more processors determining whether the message received by the cellular telephone is either of the first or second message type;   if the message is of the first message type, the one or more processors storing the message in the first set of memory locations; and   if the message is of the second message type, the one or more processors storing the message in the second set of memory locations;   wherein the first set of memory locations can be overwritten from the cellular telephone, and the second set of memory locations cannot be overwritten from the cellular telephone.   
     
     
         59 . The system of  claim 55 , wherein the cellular telephone receiving is performed without requiring end user interaction. 
     
     
         60 . The system of  claim 55 , wherein the write command comprises an embedded command. 
     
     
         61 . The system of  claim 55 , wherein the messages of the first and second types are transmitted using a common protocol. 
     
     
         62 . The system of  claim 55 , wherein the messages of the first and second types are formatted using a common formatting method. 
     
     
         63 . The system of  claim 55 , wherein one or more processors comprise a first processor and a second processor, the system further comprising;
 the first processor determining whether the message received by the cellular telephone is of either the first or second message type; and   the second processor executing the write command.   
     
     
         64 . The system of  claim 55 , wherein one or more processors comprise a first processor and a second processor, the system further comprising;
 the first processor determining whether the message received by the cellular telephone is of either the first or second message type, and, if it is determined that the message is of the first message type, writing at least a portion of the text to be displayed to the first set of memory locations; and   the second processor executing the write command and writing the associated write data to the second set of memory locations.   
     
     
         65 . The system of  claim 55 , further comprising:
 if the message received by the cellular telephone is of the second message type and contains invalid data, the second processor discards the message.   
     
     
         66 . The system of  claim 55 , further comprising:
 if the message received by the cellular telephone is of the second message type, the second processor determining whether it contains corrupt or invalid data, and if the second processor determines that the message contains corrupt or invalid data, the second processor discarding the message.