JP3438466B2 - CATV system - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a CATV system such as a CATV terminal having a function of enabling or disabling a pay program to be received by remote control from a CATV center. It is. 2. Description of the Related Art Conventionally, this type of CATV terminal has the following configuration. That is, in the CATV system, the pay program is scrambled, and only the channel contracted by the subscriber operates the descrambler to enable reception. Information of a channel the subscriber contract, E ² P provided in the CATV terminal
The data is stored as data in a designated area of a storage unit such as a ROM or a RAM, and the control unit turns on / off the descrambler based on the data in the storage unit. [0003] Such a conventional CA
In the configuration of the TV terminal, since the location of the contract channel data stored in the storage unit is fixed, there are the following problems. That is, it is possible for an eavesdropper to easily rewrite all pay programs into receivable data by a memory programmer using an IC clip or the like, and that even if the eavesdropping is performed, the CATV station does not know that the eavesdropping has been performed. There was a problem. An object of the present invention is to provide a CATV system in which data in a storage unit is not eavesdropped even if it is illegally rewritten. [0005] In order to achieve the above object, the cable of the CATV system of the present invention is formed in a tree shape.
When the branch destination is connected to the CATV terminal,
Both are output from the head end to this branch point
It has a function to stop data transmission and the CATV transmission unit
A CATV broadcast repeater is provided, and in the head end section,
Periodically collect contract data stored in the storage unit and
Data collected from the storage unit and in the head end unit
Compares contract data with subscribers and results do not match
Sometimes, based on this result, the CATV broadcast repeater
Only the corresponding CATV terminal stops CATV broadcasting . Thus, wiretapping can be prevented. [0007] The invention according to claim 1 of the present invention provides a CATV station and a cable connected to the CATV station.
This cable has a CATV
CATV system to which a TV receiver is connected via a terminal
A CATV station , comprising: a head end unit;
A data modulator connected to an output of the head end unit, a CATV transmitter connected to an output of the data modulator, a distributor connected between an output of the CATV transmitter and the cable, A data receiving unit is provided between the other terminal of the distributor and the input of the head end unit, and the cable is branched in a tree shape.
When this branch destination is connected to the CATV terminal,
In addition, the output from the head end section is
Data transmission and the transmission stop function of the CATV transmission unit.
A CATV terminal having a CATV broadcast repeater
The an input terminal to which the Ru is connected to the cable, a branch circuit connected to the input terminal, a tuner connected to the first terminal of the branch circuit, the descrambler coupled to the output of the tuner an output terminal that will be connected to the television receiver is connected to the output of the descrambler, the a second connection data demodulation unit to the terminal of the branch circuit, connected to the control unit to the data demodulation unit When the third terminal and the two-way section connected between the control unit, the output of the control unit is the storage unit that is connected to the control unit is connected to the descrambler of the branch circuit is provided in the head end portion, and a subscriber regularly the collect stored contract data to the storage unit, in the head-end unit and the data collected from the storage unit Comparing the agreement data, when the results do not match, the CATV broadcast on the basis of the result
Stop CATV broadcasting only for the corresponding CATV terminal at the repeater
This is a CATV system for stopping
Because the data in the storage unit of the ATV terminal can be compared with the data transmitted by the CATV station,
Even if the data in the storage unit of the CATV terminal is rewritten, the CATV station side identifies the subscriber's CATV terminal.
The CATV broadcast is stopped by the CATV broadcast repeater.
Can be made. Therefore, eavesdropping can be prevented
You. An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 shows a block diagram of the CATV system. In FIG. 1, C of the present embodiment
The ATV system includes a CATV station 1 and this CATV station 1
, A CATV broadcast repeater 9 connected to the cable 8, and a CATV broadcast repeater 9
And a CATV terminal 3 connected to the terminal.
Further, inside the CATV station 1, a data receiving unit 2 is provided.
Headend unit 4, data modulation unit 5, CATV transmission unit 6
have. The CATV system configured as described above will be described in more detail below. 1 is CATV
The station 2 is a data receiving unit for receiving data transmitted from the CATV terminal 3, and the reference numeral 4 is for storing reception contract data of the subscriber of the CATV terminal 3, and the like. This is a head-end unit for comparing with reception contract data. The head end unit 4 is connected to a CATV transmission unit 6 via a data modulation unit 5. Then, the output of the CATV transmission unit 6 is output via the distributor 7 to the CAT
Connected to V cable 8. The other side of the distributor 7 is connected to the data receiving unit 2. CATV
The cable 8 is branched in a tree shape, and a CATV terminal 3 installed in each home is connected to an end thereof. A CATV broadcast repeater 9 having a function of receiving data of the head end unit 4 and stopping transmission of the CATV transmission unit 6 is installed at a branch point immediately before branching to each home. FIG. 2 is a block diagram of the CATV terminal 3. In the CATV terminal 3, a CATV cable 8 is connected to an input terminal 10 as shown in FIG. This input terminal 10 is connected to a branch circuit 11, one output of which is connected to an up-down converter 12. The output terminal of the up-down converter 12 is connected to an output terminal 14 via a descrambler 13, and the output terminal 14 is connected to a television receiver 22. The other output of the branch circuit 11 is connected to a control unit 17 via a data demodulation unit 15 and a bidirectional unit 16. The control unit 17 further includes a storage unit 18 and a remote control receiving unit 1.
9, a display unit 20, a keyboard 21 and the like are connected. The CATV station and the CA configured as described above
The operation of the TV terminal will be described. The subscriber applies to the CATV station 1 for the channel to which the subscriber wants to subscribe, and the CATV station 1
The data is transmitted by the data demodulator 15 and the data is received by the data demodulator 15. The controller 17 decodes the data and
8 is stored. When the subscriber selects a channel by using the keyboard 21 or the remote control transmitter 23 (not shown), the control unit 17 operates to enable or disable the designated channel based on the data in the storage unit 18. Is operated. The CATV station 1 periodically downloads data stored in the storage unit 18 of the CATV terminal 3 via the bidirectional unit 16 and compares the data with the subscriber data stored in the head end unit 4. I do. If the data stored in the head end unit 4 and the data downloaded from the storage unit 18 are different, the subscriber determines that the data in the storage unit 18 has been rewritten and eavesdropped, and the eavesdropping is performed. By making all the channels of the subscriber's cable television terminal 3 unreceivable and displaying a warning message on the television receiver 22 via the subscriber's CATV terminal 3, eavesdropping can be prevented. However, if eavesdropping continues, the broadcast to the subscriber connected to the CATV broadcast repeater 9 is stopped to further improve the eavesdropping prevention function. As described above, in the present embodiment, even if the data in the storage unit 18 is rewritten for eavesdropping, the pay program is not eavesdropped. As described above, according to the present invention, CATV
The system cable is branched into a tree,
Is connected to the CATV terminal and this branch point
Receives the data output from the head end unit and
CATV broadcast repeater with transmission stop function of V transmitter
Provided, and the CATV end is periodically
Collect contract data stored in the storage unit of the
Data collected from the storage unit and
Compare contract data with entrants and if the results do not match
The CATV broadcast repeater based on the result.
Only the corresponding CATV terminal stops CATV broadcasting.
Therefore, even if the eavesdropper is in the storage unit of the CATV terminal,
Even if the data is rewritten, join on the CATV station side
Identify the CATV terminal of the user and make it a CATV broadcast repeater
It is possible to further stop CATV broadcasting. Follow
Te, it is possible to prevent eavesdropping.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a CATV system according to one embodiment of the present invention. FIG. 2 is a block diagram of the same CATV terminal. DESCRIPTION OF SYMBOLS 1 CATV station 2 Data receiving unit 3 CATV Terminal 4 Head end unit 5 Data modulation unit 6 CATV transmission unit 7 Distributor 8 CATV cable 9 CATV broadcast repeater 12 Up / down converter 13 Disc rambler 15 Data demodulation unit 16 Bidirectional unit 17 Control unit 18 Storage unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 7/10 H04N ^7/ 16-7/173 H04N ^7/ 20-7/22 H04H 1/02

Claims (1)

(57) [Claims 1] A CATV station and a terminal connected to the CATV station.
Cable with the output
To which a TV receiver is connected via a CATV terminal
In the ATV system, the CATV station includes a head end unit, a data modulation unit connected to an output of the head end unit, and a CA connected to an output of the data modulation unit.
A TV transmitter unit, and connected to the distributor between the cable and the output of the CATV transmission unit, the connected data receiver between the input of the headend unit and the other terminal of the distributor Along with the cable
The branch is made, and the branch destination is connected to the CATV terminal.
At the branch point, and
Stops transmission of the CATV transmission unit after receiving input data
A CATV broadcast repeater having a function;
The terminal, an input terminal to which the Ru is connected to the cable, the branch circuit connected to the input terminal, a tuner connected to the first terminal of the branch circuit, the disk connected to the output of the tuner and Rambler, and an output terminal that will be connected to the television receiver is connected to the output of the descrambler, and a data demodulation unit connected to said second terminal of the branch circuit, is connected to the data demodulation unit A control unit, a bidirectional unit connected between the third terminal of the branch circuit and the control unit, and a storage connected to the control unit while the output of the control unit is connected to the descrambler. parts and are provided, in the head-end unit, it collects the contract data stored in the regular the storage unit, in the head-end unit and the data collected from the storage unit pressure Comparing the agreement data of the user, when the results do not match, the CAT on the basis of the result
Only the applicable CATV terminal in the V broadcast repeater is CATV released
CATV system to stop sending .