Enhanced security memory access method and architecture

摘要

A memory device (102) includes: at least one storage area (108) for storing data; a protection control structure (234) adapted to selectively allow an external device (104) access to the at least one storage area of the memory, the storage area being not freely accessible by the external device if protected; a control logic (205,220) adapted to identify an access request by the external device to the at least one storage area and cooperating with the protection control structure for managing an unlock procedure for selectively granting the external device at least temporary access rights to the storage area if protected; means for providing a first code (RND) to the external device in said unlock procedure; means for receiving a second code from the external device in response to said first code; means for verifying (240,229) validity of the received second code. The means for verifying validity are adapted to ascertain a correspondence of the second code with the first code based on a predetermined relationship. The control logic instructs the protection control structure to grant access to the storage area if the validity of the received second code has been verified. The first code issued by the memory device to the external device upon receiving an access request is changed after performing predetermined number of unlock procedures.