The internal architecture of a SIM card is organized around a processor and there are the following three different types of memory:
1- Read Only Memory (ROM): this memory contains the card operating system along with one or more applications.
2- Electrically Erasable Programmable Read Only Memory (EEPROM): this memory contains all parameters defined by the GSM/3GPP technical specifications and data manipulated by applications. Information saved in this memory is persistently stored even if the mobile station has been powered off.
3- Random Access Memory (RAM): this memory contains data manipulated by applications. Information stored in this memory is lost when the mobile station is powered off.
The storage structure of a SIM card is based on a hierarchy of folders and files. The root folder is known as the Master File (MF), a normal folder is known as a Dedicated File (DF), and a file is known as an Elementary File (EF).
1- Read Only Memory (ROM): this memory contains the card operating system along with one or more applications.
2- Electrically Erasable Programmable Read Only Memory (EEPROM): this memory contains all parameters defined by the GSM/3GPP technical specifications and data manipulated by applications. Information saved in this memory is persistently stored even if the mobile station has been powered off.
3- Random Access Memory (RAM): this memory contains data manipulated by applications. Information stored in this memory is lost when the mobile station is powered off.
The storage structure of a SIM card is based on a hierarchy of folders and files. The root folder is known as the Master File (MF), a normal folder is known as a Dedicated File (DF), and a file is known as an Elementary File (EF).
