Patent ID: 8291482

Claim:
A communication terminal comprising: a memory and a central processing unit in communication with the memory; a receiving unit that receives content; and a storing unit that stores the content received by the receiving unit in the memory; wherein the central processing unit is executable to store content identification data identifying the content in a data storage module that is a separate and independent device attached to the communication terminal at a time when the content is received, the data storage module comprising a processor and being detachable from the communication terminal; the central processing unit further executable, if use of the content stored in the memory is instructed when any data storage module is attached to the communication terminal, to determine whether the content identification data identifying the content matches identification data obtained from the any attached data storage module; and the central processing unit further executable to permit use of the content in response to determination by the central processing unit that content identification data identifying the content matches identification data obtained from the any attached data storage module.