11.113GPPRelease 1999Specification of the Subscriber Identity Module - Mobile Equipment (SIM-ME) InterfaceTS
H.2.1 A-KEY (ANSI-41 Authentication Key)
The A-Key is only accessible to the algorithm used for Key generation. The A-Key may be programmed into the SIM directly by the service provider, or it may be programmed into the SIM through a specific over the air procedure. The A‑Key is not accessible by the mobile equipment, therefore the method of storage on the SIM is not specified in this document. The SIM command A-KEY_VALIDATION is used to store the A-Key on the SIM.
H.2.2 SSD (Shared Secret Data)
The Shared Secret Data is accessible only to the Authentication and the Key Generation functions. SSD is not accessible by the mobile equipment, therefore the method of storage on the SIM is not specified in this document.
An additional Status Code is defined for SSD updating as follows:
98, 34 Error, Update SSD order sequence not respected (should be used if SSD Update commands are received out of sequence).