JP2013058949A - Receiver, reception system and reception method performing viewing control on broadcasting signal from broadcaster - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem of a system where more than one limited reception is mixed for one content that, in the conventional method, transmission capacity of broadcasting signals must be doubled in order for a CATV station to perform unique viewing control for users while sustaining service provision to the users under viewing control by a broadcaster, because it is required to transmit the broadcasting signals of a pass-through system and a re-multiplexing system.SOLUTION: A CATV station adds a second ECM for performing unique viewing control to a broadcasting signal generated by a broadcaster thus generating a SimulCrypt signal. More specifically, the CATV station separates a first ECM from the broadcasting signal sent from the broadcaster, the first ECM thus separated takes out a scramble key at a decoding section of an IC card, and an ECM generation unit generates a second ECM by using the scramble key, and sends the second ECM to a multiplexing unit where the second ECM is multiplexed with the broadcasting signal thus generating a broadcasting signal.

Description

The present invention relates to a conditional access system for specifying a receiver and permitting reception in pay broadcasting or the like, and more particularly to a conditional access system in a cable television (hereinafter referred to as CATV) station.

Conventionally, two methods, a pass-through method and a re-multiplexing method, are known as methods for retransmitting a scrambled broadcast signal transmitted from a broadcast center or the like to a receiving terminal device.
In the pass-through method, the broadcast signal is retransmitted only by changing a part of the program arrangement information without performing descrambling and re-scramble of the content in the CATV station. In this system, all the limited reception management is performed by the broadcaster. On the other hand, in the remultiplexing method, the CATV station descrambles the received stream, adds original limited reception information, and simultaneously re-scrambles the content and sends it to the CATV terminal device.
For example, in Japanese Patent Application Laid-Open No. 2001-145075, a relay device adopting a pass-through method in a CATV station can manage a receiving terminal device having jurisdiction using a broadcaster's limited reception function, and can restrict viewing of the terminal device. The viewing control method in the CATV station is generally widely known.

  Further, a system called simulcrypt is known as a system for mixing two or more limited receptions for one content.

JP 2001-145075 A

  However, in the conventional method, in order for the CATV station to perform the unique viewing control to the user while continuing to provide the service to the user who is receiving the viewing control by the broadcaster, the broadcast of the pass-through method and the remultiplexing method is used. It was necessary to transmit the signals separately, and the transmission capacity of the broadcast signal was doubled.

  An object of the present invention is to solve the above-mentioned problem, and a second ECM for CATV station to independently control viewing is added to a broadcast signal generated by a broadcaster, It generates a simultaneous crypto broadcast signal.

  Accordingly, in the present invention, the first ECM is separated from the broadcast signal sent from the broadcaster's station equipment by the separation unit of the CATV station limited reception device, and the separated first ECM is sent to the IC card decoding unit. The scramble key Ks is extracted, the second ECM is generated by the ECM generation unit using the scramble key Ks, is sent to the multiplexing unit, and is multiplexed with the broadcast signal to generate a simultaneous crypto broadcast signal. A limited reception is realized by such a method.

  ADVANTAGE OF THE INVENTION According to this invention, the viewing control with respect to the user who has contracted with the broadcaster and the viewing control with respect to the user contracted with the CATV station can be made compatible, and a service can be provided without increasing the transmission amount of the broadcast signal. It becomes possible.

It is a figure explaining the configuration of a CATV station limited reception system in an embodiment of the present invention. It is a flowchart explaining the ECM / EMM generation process of the conditional access system of the CATV station in one embodiment of this invention. It is a flowchart explaining the PMT / CAT update process of the conditional access system of the CATV station in one embodiment of this invention. It is a flowchart explaining the timing control process of the conditional access system of the CATV station in one embodiment of this invention. It is an example of PMT (program map table) in one embodiment of the present invention. It is an example of CAT (conditional access table) in an embodiment of the present invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a configuration example of a CATV station limited reception system according to an embodiment of the present invention.

  In this embodiment, only a main functional unit is shown, and a conditional access system for viewing a program using an IC card inside a subscriber management device, viewing information collection device, or terminal device not shown in this component Since is not directly related to the present invention, description thereof is omitted.

  The CATV station limited reception apparatus 1 is an apparatus including a separation unit 11, a delay circuit 12, a PMT / CAT update unit 13, an ECM generation unit 14, a multiplexing unit 15, and an EMM generation unit 16.

  The separation unit 11 transmits the broadcast signal received from the broadcaster to the delay circuit 12 as it is. Here, the broadcast signal is an image that is scrambled (encrypted) with an EMM (individual information) including information on the work key Kw encrypted with the master key Km of the limited reception method obtained from the broadcaster and the scramble key Ks. And ECM (common information) including scramble key Ks encrypted with work data Kw and audio data (content information). In addition, the separation unit 11 separates various information included in the broadcast signal separately from the transmission of the broadcast signal to the delay circuit. More specifically, a first PMT (program map table) and a contract in which information related to the packet ID of a TS packet that transmits common information using a packet ID of a TS packet constituting a program from a broadcast signal as a key is described. A first CAT (conditional access table) in which information related to the packet ID of the TS packet transmitting the information is described is separated and transmitted to the PMT / CAT update unit. The separating unit 11 separates the first ECM in which the common information is described from the broadcast signal using the packet ID of the TS packet constituting the program as a key, and transmits the first ECM to the IC card 2.

  Here, each unit described above may be implemented by modular hardware, or may be realized by software using a processing device (processing unit) such as a CPU.

  The IC card 2 is a device having a decryption unit 21. The decryption unit 21 extracts the scramble key Ks based on the received first ECM and transmits it to the ECM generation unit 14.

  The ECM generation unit 14 generates a second ECM based on the received Ks and transmits it to the multiplexing unit 15.

  Since the delay circuit 12 is synchronized with the processing of the PMT / CAT update unit 13 and the processing of the IC card 2 and the ECM generation unit 14, the broadcast signal is accumulated and waited based on the delay time set in the delay circuit 12 in advance. After that, it is delayed and transmitted to the multiplexing unit 15.

  The PMT / CAT update unit 13 adds the received first PMT (program map tail) and first CAT (conditional access table) to the second ECM packet ID and the second EMM packet ID. The second PMT (program map tail) and the second CAT (conditional access table) are updated and transmitted to the multiplexing unit 15.

  The EMM generation unit 16 generates a second EMM including information on the work key Kw encrypted with the master key Km, and transmits the second EMM to the multiplexing unit 15.

  The multiplexing unit 15 multiplexes the second ECM, the broadcast signal received from the delay circuit, the second PMT (program map tail), the second CAT (conditional access table), and the second EMM, thereby performing simultaneous crypto broadcast. A signal is generated and transmitted to the CATV network 3.

  The terminal device 4 includes a descrambling unit 41 and an IC card 42. When receiving the simultaneous crypto broadcast signal from the CATV network 3, the terminal device 4 takes out the first or second ECM according to the identification number CA_system_id passed from the IC card and passes it to the IC card 42. The IC card 42 uses the decryption unit corresponding to the first or second ECM of the IC card 42 to extract the scramble key Ks from the received ECM and set the scramble key Ks in the descrambling unit 41 (in this embodiment, In particular, it is assumed that this IC card includes a decryption unit corresponding to the second ECM). The descrambling unit 41 descrambles the simultaneous crypto broadcast signal to generate video and audio.

  FIG. 2 is an example of an ECM / EMM generation process flow of the conditional access system of the CATV station in this example.

  The separation unit 11 first extracts the first ECM from the broadcast signal as received from the broadcaster (step S111).

  Next, the separation unit 11 transmits the extracted first ECM to the IC card 2 (step S112).

  The decryption unit 21 of the IC card 2 generates a scramble key Ks from the first ECM (step S113).

  The decryption unit 21 transmits the generated scramble key Ks to the ECM generation unit 14 (step S114).

  The ECM generation unit 14 generates a second ECM based on the scramble key Ks (step S115).

  The ECM generation unit 14 transmits the second ECM to the multiplexing unit 15 (step S116).

  After the second ECM is transmitted to the multiplexing unit 15, the EMM generation unit 16 generates a second EMM including information on the work key Kw encrypted with the master key Km (step S117).

  The multiplexing unit 15 transmits the second EMM to the multiplexing unit 15 and ends the process (step S118).

  FIG. 3 is an example of the PMT / CAT update processing flow of the conditional access system of the CATV station in this example.

  The separation unit 11 first extracts a first PMT (program map tail) and a first CAT (conditional access table) from the broadcast signal received from the broadcaster (step S121).

  Next, the separation unit 11 transmits the extracted first PMT (program map tail) and first CAT (conditional access table) to the PMT / CAT update unit 13 (step S122).

  Based on the first PMT (program map tail) and the first CAT (conditional access table), the PMT / CAT update unit 13 uses the ECM packet ID and the EMM packet ID as keys to set the second PMT (program map). Tail) and the second CAT (conditional access table) (step S123).

  The PMT / CAT update unit 13 transmits the second PMT (program map tail) and the second CAT (conditional access table) to the multiplexing unit 15 and ends the process (step S124).

  FIG. 4 shows an example of the timing control processing flow of the conditional access system of the CATV station in this embodiment.

  The separating unit 11 first transmits a broadcast signal received from a broadcaster to a delay circuit 12 for matching a plurality of processing flows. (Step S131).

  The delay circuit 12 determines the elapsed time of the broadcast signal received from the stored broadcaster, and uses the delay time (N seconds) preset in the delay circuit. If N seconds have not elapsed, the process proceeds to step S132. When N seconds have elapsed, a broadcast signal is transmitted to the multiplexing unit 15. (Step S133). Here, the delay time set in advance in the delay circuit is a time considering the processing time of the decoding unit 21, the PMT / CAT update unit 13, the ECM generation unit 14, and the like.

  The multiplexing unit 15 multiplexes the second ECM, the broadcast signal received from the delay circuit, the second PMT (program map tail), the second CAT (conditional access table), and the second EMM, and finishes the process (step) S134).

  FIG. 5 shows an example of a PMT (program map table) in this embodiment. PMT describes CA_system_id and EMM_PID.

  FIG. 6 is an example of a CAT (conditional access table) in this embodiment. CAT describes CA_system_id and ECM_PID.

  As described above, it is possible to achieve both viewing control for a user who has contracted with a broadcaster and viewing control for a user who has contracted with a CATV station, and provide a service without increasing the transmission amount of broadcast signals. It becomes.

1: CATV station limited reception device, 11: separation unit, 12: delay circuit, 13: PMT / CAT update unit, 14: ECM generation unit, 15: multiplexing unit, 16: EMM generation unit, 2: IC card, 21: Decoding unit, 3: CATV network, 4: terminal device, 41: descrambling unit, 42: IC card.

Claims (10)

A receiving device that restricts viewing on broadcast signals from broadcasters,
A separation unit, an ECM generation unit, a delay unit, and a multiplexing unit;
The separation unit receives a broadcast signal from a broadcaster, extracts a first ECM including a scramble key included in the received broadcast signal, and extracts the extracted first ECM outside the receiving device. Transmit to an external device, transmit the received broadcast signal to the delay unit,
The ECM generation unit generates a second ECM based on the scramble key generated from the first ECM transmitted from the external device, and transmits the generated second ECM to the multiplexing unit;
The delay unit accumulates the broadcast signal received from the separation unit for a predetermined time, and transmits the broadcast signal to the multiplexing unit after a predetermined time has elapsed,
The multiplexing unit multiplexes the second ECM transmitted from the ECM generation unit and the broadcast signal transmitted from the delay unit, and transmits the multiplexed information to a terminal device outside the receiving device. To
A receiving apparatus. The receiving device according to claim 1,
The receiving apparatus according to claim 1, wherein the predetermined time is at least a predetermined time according to a processing time of the ECM generation unit. A receiving system comprising the receiving device according to claim 1 and the external device,
The external system generates the scramble key from the first ECM received from the reception device, and transmits the scramble key to the ECM generation unit. The receiving system according to claim 3, wherein
Furthermore, a terminal device is provided,
The terminal device includes a receiving unit, a decoding unit, and a descrambling unit,
The receiving unit receives the multiplexed information,
The decryption unit generates a scramble key corresponding to the second ECM from the second ECM included in the received multiplexed information by using a second external device provided in the terminal device. Send to
The descrambling unit descrambles the multiplexed information based on a scramble key corresponding to the transmitted second ECM;
A receiving system. The receiving system according to claim 3 or 4,
The receiving system, wherein the external device is an IC card. A receiving method that restricts viewing of broadcast signals from broadcasters,
Receiving a broadcast signal from a broadcaster;
Extracting a first ECM including a scramble key included in the received broadcast signal;
Transmitting the extracted first ECM to an external device, and transmitting the received broadcast signal to the delay unit;
Generating a second ECM based on a scramble key generated from the first ECM transmitted from the external device;
Transmitting the generated second ECM to the multiplexing unit;
The delay unit accumulates the received broadcast signal for a predetermined time, and transmits to the multiplexing unit after a predetermined time;
The multiplexing unit multiplexes the transmitted second ECM and the broadcast signal transmitted from the delay unit;
Transmitting the multiplexed information to a terminal device that receives the multiplexed information;
A receiving method comprising: The reception method according to claim 6,
The reception method according to claim 1, wherein the predetermined time is at least a predetermined time according to a processing time of the step of generating the first ECM. The receiving method according to claim 6 or 7,
The external device generates the scramble key from the received first ECM, and transmits the scramble key to the ECM generation unit. The receiving method according to claim 8, wherein
After the step of transmitting the multiplexed information to the terminal device,
Receiving the transmitted multiplexed information at the terminal device;
Generating a scramble key corresponding to the second ECM from the second ECM included in the received multiplexed information using a second IC card;
Descrambling the multiplexed information using the generated scramble key;
A receiving method comprising: The reception method according to any one of claims 6 to 9,
The receiving method, wherein the external device is an IC card.

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