Abstract: A power management technique for a Subscriber Identity Module (SIM), makes use of a voting process to determine when to power-up and power-down the SIM. In particular, the voting process determines whether software modules running on a wireless communication device (WCD) require current or imminent access to the SIM. The voting process is designed to make more efficient use of the SIM without sacrificing performance. A modified security authorization process can be added, in which the WCD caches a user access code in memory for authenticating the user to the SIM to gain access to the secure features of the SIM. The security verification process avoids the need for the user to enter the access code each time the SIM is powered up in the course of the power management routine, reducing user inconvenience and maintaining performance.

Abstract: Power management techniques for a Subscriber Identity Module (SIM) of a wireless communication device (WCD) are described tat make use of a unique identifier for the SIM. In particu1ar a processor within the WCD reads a first unique identifier from the SIM when power is initially supplied to the WCD, and stores the first unique identifier within a computer-readable medium within the WCD. During a power management cycle, where power is terminated and then re-supplied to the SIM, the processor again receives a unique identifier from the SIM and compares the second unique identifier with the stored unique identifier. These tecbniques are useful in detecting whether the attached SIM has been exchanged for a different SIM while powered down during a power management cycle.

Abstract: A power management technique for a Subscriber Identity Module (SIM), makes use of a voting process to determine when to power-up and power-down the SIM. In particular, the voting process determines whether software modules running on a wireless communication device (WCD) require current or imminent access to the SIM. The voting process is designed to make more efficient use of the SIM without sacrificing performance. A modified security authorization process can be added, in which the WCD caches a user access code in memory for authenticating the user to the SIM to gain access to the secure features of the SIM. The security verification process avoids the need for the user to enter the access code each time the SIM is powered up in the course of the power management routine, reducing user inconvenience and maintaining performance.

Abstract: Power management techniques for a Subscriber Identity Module (SIM) of a wireless communication device (WCD) are described that make use of a unique identifier for the SIM. In particular, a processor within the WCD reads a first unique identifier from the SIM when power is initially supplied to the WCD, and stores the first unique identifier within a computer-readable medium within the WCD. During a power management cycle, where power is terminated and then re-supplied to the SIM, the processor again receives a unique identifier from the SIM and compares the second unique identifier with the stored unique identifier. These techniques are useful in detecting whether the attached SIM has been exchanged for a different SIM while powered down during a power management cycle. This is advantageous in verifying the integrity of the SIM for other software or hardware modules within the WCD that need to access or otherwise utilize the SIM.