Back to results
US 2005/0166050 A1Published application
Encoded data receiving device and method for updating decoding keys
AssigneeFujitsu Limited
InventorMakoto Kosaki
Life of this patent
Estimating the term…
Loading patent…
Loading patent…
AssigneeFujitsu Limited
InventorMakoto Kosaki
Estimating the term…
It is an object to provide an encoded data receiving device and a method for updating a decoding key represented by DTCP standards capable of eliminating shifts in update timings of the public key NC between a data receiving device and a data transmitting device without increasing the amount of packets for inquiries between both devices. In the check portion, success or failure in data decoding is checked on the basis of fixed information that are disposed at specified bit positions of decoded data. In the determination portion, when check results indicating that decoding of data has failed are consecutively output by the check portion by a specified number of times, a determination signal indicating that update of the decoding key following update of the encoding key of the data transmitting device has failed is output whereupon a calculating portion performs update of the decoding key on the basis of the determination signal.
An encoded data receiving device in which transmitted packets, which include data encoded by an encoding key that is updated at specified time intervals and update information of the encoding key, are received and in which the data are decoded by a decoding key that is updated on the basis of the update information, the device comprising:
A method for updating decoding keys in which transmitted packets, which include data encoded by an encoding key that is updated at specified time intervals and update information of the encoding key, are received and in which the data are decoded by a decoding key that is updated on the basis of the update information, the method including:
Dependencies are inferred from the claim text.