A device and method for encrypting content in an encryption device
including a content-key storage section is disclosed. The method includes
generating a content-key used for encrypting content based on random
numbers and storing the generated content-key in the content-key storage
section, encrypting the content-key used for encrypting the content so as
to obtain an encrypted content-key and outputting the encrypted
content-key to outside of the encryption device, determining whether or
not a value of the content-key storage section in its initial state and a
current value of the content-key storage section are different, and when
it is determined that the value of the content-key storage section in its
initial state and the current value of the content-key storage section
are different, encrypting the content using the current value of the
content-key storage section as a content-key so as to obtain a second
output data and output the second output data to outside of the
encryption device, wherein, for the determination step, a register stores
a value of the content-key storage section at the time that said register
receives a Power On Reset (POR) signal, and wherein the POR signal is a
signal which pulses only once immediately after power-on or immediately
after reset, so that the content-key storage section is in an initial
state immediately after a corresponding power-on or reset of the
encryption device.