| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To allow an image processor to generate an encryption key, which can be hardly extracted, in cooperation with an external device. <P>SOLUTION: The image processor generates a first encryption key when the setup of reliance on external devices is valid. The image processor confirms that a plurality of external devices having reliance relation are powered on, and requests first encryption keys from the respective external devices. Each external device transmits a first encryption key to the image processor. The image processor generates an encryption key from a plurality of first encryption keys from the external device and its own first encryption key. The image processor stops operating or limits execution of some of functions when an external device having reliance relation is powered off or when the reception of the first encryption key from the external device ends in failure. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
