Patent ID: 7668335

Claim:
A communication device comprising: one or more processors, the one or more processors being programmed to provide a platform program configured to control functional units that are included in the device, and being programmed to provide an application that runs on the platform program, the platform program having a data reception function that can receive content data for which a signature can be generated; and a user identity module which generates a signature for the received content data, wherein the application is configured to judge whether it is possible for the communication device to generate a signature for the received data by making a request to the user identity module to request whether a generation of the signature is possible based on version information of the user identity module, and the user identity module generates a signature for the content data if it is possible to generate the signature, and delivers the signature to the platform program; the application is configured to output the received content data to the platform program when it is judged that signature generation can be performed by the communication device; the platform program integrates the signature into the content data to generate signed content data; and the application transmits the signed content data, and wherein the user identity module is detachable from the communication device, and wherein the application is further configured to verify the version information indicating a version of a signature generating function of the user identity module, and does not output data to the platform program when the user identity module is judged not to have the signature generating function on a basis of the version information, and outputs data to the platform program when the user identity module is judged to have the signature generating function on a basis of the version information.