Patent ID: 8209534

Claim:
A contents transmitter apparatus, comprising: network communication processing means for conducting transmission of data through a network; transmission contents producing means for supplying contents to be transmitted to a contents receiver apparatus which is connected to the contents transmitter apparatus through said network, to said network communication processing means; authentication means for receiving an authentication request from said contents receiver apparatus for executing an authentication process between said contents transmitter apparatus and said contents receiver apparatus, and for transmitting a time authentication request for a time authentication to said contents receiver apparatus; encryption means for producing key information upon the basis of information which is obtained through execution of the authentication process by said authentication means, and for conducting an encryption process on the contents with said key information; timer means for measuring a first time-period beginning from said transmission of the time authentication request until reception of a response to said time authentication request; and registration means for registering equipment information about said contents receiver apparatus, wherein: said authentication means registers equipment information unique to said contents receiver apparatus by using said registration means, when a measurement result of said timer means does not exceed a predetermined value, said authentication means does not conduct said time authentication by using said timer means in the case where said equipment information unique to said contents receiver apparatus is registered in said registration means, and said authentication means executes a measurement, by using said timer means, of a second time-period which is an accumulated time-period for contents transmission after said equipment information of said contents receiver apparatus is registered by said authentication means using said registration means, and deletes said equipment information by using said registration means depending upon a result of said measurement of said second time-period.