Stream Generation Method, Broadcast Receiving Apparatus, and Display Method

• US 20090323948A1
• Filed: 05/15/2007
• Published: 12/31/2009
• Est. Priority Date: 05/16/2006
• Status: Active Grant

• Current Assignee: KDDI Corporation, Kyocera Corporation, Nippon Hoso Kyokai
• Original Assignee: KDDI Corporation, Kyocera Corporation, Nippon Hoso Kyokai
• Inventors: Fukushima, Masaru, Kimura, Takeshi, Kiyomoto, Shinsaku, Ohtake, Go, Shibata, Tatsuo, Kokubun, Hideki, Majima, Keigo, Sugie, Shuichi
• Granted Patent: US 8,532,292 B2
• Time in Patent Office: Days
• US Class Current: 380/210
• CPC Class Codes: H04L 2209/56 Financial cryptography, e.g. electronic payment or e-cash
• CPC Class Codes: H04L 2209/601 Broadcast encryption
• CPC Class Codes: H04L 2209/80 Wireless network architectures or network communication protocols for wireless network security H04W12/00
• CPC Class Codes: H04L 9/065 Encryption by serially and continuously modifying data stream elements, e.g. stream cipher systems, RC4, SEAL or A5/3
• CPC Class Codes: H04N 21/41407 embedded in a portable device, e.g. video client on a mobile phone, PDA, laptop constructional details of equipment or arrangements specially adapted for portable computer application G06F1/1626; arrangements specially adapted for mobile receivers in broadcast systems H04H20/57
• CPC Class Codes: H04N 21/4405 involving video stream decryption
• CPC Class Codes: H04N 21/63345 by transmitting keys key distribution for secret or secure communication H04L9/08; network support of key management H04L63/06
• CPC Class Codes: H04N 7/1675 Providing digital key or authorisation information for generation or regeneration of the scrambling sequence pseudo-random number generators in general G06F7/58

Abstract

Provided is a system far receiving a initialization packet containing an initial vector for initializing stream encryption algorithm and an identifier of a key for decrypting an encrypted stream, initializing a decryption modules and decrypting the encrypted stream, wherein the system stores an identifier of a key which is needed to decrypt a next program in a initialization packet of a current program and informs a user of whether a desired key has been acquired or not at timing close to start time of the next program.

Claims

1. A stream generation method comprising:

storing an identifier of a key for decrypting stream-encrypted data of a current program in initialization packets for initializing stream encryption algorithm;

inserting the initialization packets into a stream; and

storing an identifier of a key for decrypting stream-encrypted data of a next program in a predetermined initialization packet among the initialization packets.

2. The stream generation method of claim 1, storing the identifier of the key for decrypting stream-encrypted data of the next program in the initialization packets at a predetermined interval.

3. The stream generation method of claim 1, storing the identifier of the key for decrypting stream-encrypted data of the next program in a last initialization packet to be inserted into the stream.

4. A broadcast receiving apparatus comprising:

a reception unit for receiving an initialization packet containing an initial value for initializing stream encryption algorithm and an identifier of a key for decrypting stream-encrypted data of a current program, and a encrypted packet containing stream-encrypted data;

a memory for storing a key for decrypting stream-encrypted data;

a decryption unit for initializing the stream encryption algorithm using the initial value contained, in the initialization packet received, acquiring a key corresponding to the identifier of the key for decrypting stream-encrypted data of the current program, which is contained in the received initialization packet, from the memory, and decrypting stream-encrypted data contained in the encrypted packet using the key; and

a controller for determining, when an identifier of a key for decrypting stream-encrypted data of a next program is contained in the initialization packet, whether a key corresponding to the identifier is stored in the memory, and controlling a reporting unit to report the determination result.

5. The broadcast receiving apparatus of claim 4, further comprising a program information memory for storing program information, and wherein,

the controller controls the reporting unit to report the determination result with program information corresponding to the identifier among program information stored in the program information memory.

6. A broadcast receiving apparatus comprising:

a broadcast reception unit;

a display unit;

a memory for storing a key for decrypting stream-encrypted data received by the broadcast reception unit;

a program information memory for storing program information;

a controller for controlling the display unit to display a video stream of a current program being received by the broadcast reception unit, information of a following program scheduled to be broadcasted after the current program among program information stored in the memory unit, and key acquisition information indicating whether a key for decrypting a stream having steam-encrypted data of the following program has been acquired, and to display a message for promoting acquisition of the key of the following program when the key acquisition information indicates mat the key has not been acquired; and

a key acquiring unit for acquiring a key for a following program indicated by the key acquisition information as a program whose key has not been acquired.

7. The broadcast receiving apparatus of claim 6, wherein the controller controls the display unit to display the message for promoting acquisition of the key for the following program on at least a portion of a region where the video stream is displayed.

8. The broadcast receiving apparatus of claim 6, wherein when detecting information about the following program in data being received by the broadcast reception unit, the controller controls the display unit to display program information of the following program and key acquisition information indicating whether a key for the following program has been acquired, as well as the video stream received by the broadcast reception unit.

9. The broadcast receiving apparatus of claim 6, further comprising a sensitivity detection unit for detecting reception sensitivity in the broadcast reception unit, and wherein the controller controls that the key acquisition unit acquires the key for the following program based on the reception sensitivity detected by the sensitivity detection unit.

10. A display method of a broadcast receiving apparatus comprising:

displaying a video stream being received, information of a following program scheduled to be broadcasted after a current program, and key acquisition information indicating whether a key for decrypting a stream having stream-encrypted data of the following program is acquired or not on a display unit; and

displaying a message for promoting acquisition of a key for a following program on the display unit when the key acquisition information indicates that the key has not been acquired.