Method and apparatus for operating a blocked secure storage memory
View Patent ↗The invention provides an apparatus and method for service access for a mobile communication device. The apparatus can include an identity module for storing user information in the mobile communication device. The identity module can include an identity module frame, a secure storage memory coupled to the frame, the secure storage memory including a mobile communication device subscriber identity and the user information, and an identity module controller coupled to the secure storage memory and the frame, the identity module controller configured to block access to the user information and grant access to the mobile communication device subscriber identity when the identity module enters a blocked mode. The identity module controller may grant access to the mobile communication device subscriber identity in response to a request for a service access communication.
1. A method of operating an identity module in a mobile communication device comprising:
receiving an access request;
determining a blocked mode of the identity module;
granting the access request if the identity module is not in a blocked mode and the request is for a subscriber identity;
denying the access request if the identity module is in a blocked mode and the request is for user information; and
granting the access request if the identity module is in a blocked mode and the request is for the same subscriber identity.
2. The method according to claim 1 , wherein the granting the access request if the identity module is in a blocked mode step further comprises:
granting the request if the identity module is in a blocked mode and the request is for a subscriber identity for a service access communication.
3. The method according to claim 2 , further comprising placing a service access communication to a home service provider.
4. The method according to claim 1 , further comprising
entering a blocked mode of the identity module;
receiving a specific key sequence;
determining if the specific key sequence is for a service access communication; and
wherein the granting the access request if the identity module is in a blocked mode step further comprises granting the request if the identity module is in a blocked mode and the request is for a subscriber identity for a service access communication.
5. The method according to claim 1 , further comprising:
receiving an incorrect access code;
determining the number of incorrect access codes received since the last correct access code; and
entering a blocked mode of the identity module if the number of incorrect access codes since the last access code is more than a predetermined amount.
6. The method according to claim 1 , wherein the subscriber identity is an international mobile subscriber identity.
7. The method according to claim 1 , further comprising:
receiving an unblocking code; and
entering an unblocked mode of the identity module in response to the unblocking code.
8. The method according to claim 1 , further comprising transmitting a service access request on a random access channel.