JPH0818524A - Scrambler for data - Google Patents

Abstract

PURPOSE:To prevent the use of charged data without permission by starting a descrambler when a password mixed in a sent bit stream is matched with a password down-loaded in advance to a reception terminal. CONSTITUTION:When the processing is started and a receiver 2 selects a channel, a data stream to be received from the channel is analyzed by a CPU 1 and whether or not the same password is in existence in the data stream by using a password having been sent earlier and stored in a memory area 4 as a retrieval element. When no password is in existence, data inputted by a descrambler 3 is not processed. On the other hand, when the same password is retrieved, the descrambler 3 is started. Then the descrambler 3 is being started till a program being a reception object is finished. Then the descrambler is stopped by reading a program end code or by confirming it that the data input is interrupted for a prescribed time.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for preventing pay data from being used without permission when processing scrambled data in data transmission on the receiving terminal side.

[0002]

2. Description of the Related Art Conventionally, there has been known a technique for scrambling the data body so that the data cannot be used without permission in the data transmission in which importance is attached to the broadcast property. In this case, in order to effectively use the scrambled data, it is general that the receiving terminal is equipped with a descrambler such as a decoder, and the data is processed while descrambled. For example, when the image data is scrambled, the data received by the tuner may be temporarily stored in a large-scale storage device, and the image processing may be performed later while descrambling via the decoder. Data may be directly input to the decoder to perform image processing in real time.

[0003]

In the scramble technology that has been conventionally adopted, in any case, unless the data uses a specific line or a destination designated line, the scrambled data has a plurality of data. It is easily captured by the receiving terminal. Since the scramble is a communication protocol that has been agreed in advance and the character that does not change frequently, all the data can be used even if the scramble descrambling device is installed. However, in such a state, it is not possible to set the charge for each data. Further, if the protocol related to scramble is analyzed, there is a risk that the data can be freely used even in the receiving terminal that does not have the descrambler.

An object of the present invention is to solve the above-mentioned conventional problems, and to provide a scrambler capable of effectively utilizing a password to prevent unauthorized use of pay data.

[0005]

In order to achieve the above object, in the present invention, a transmission main body having a plurality of program data and a receiving terminal are connected by an arbitrary communication means, and the program data is transmitted through the communication means. A technique has been disclosed that is applied to a device that scrambles and transmits to the receiving terminal as a bitstream in which arbitrary passwords are mixed. And
The receiving terminal has a receiving device and the descrambling device, and the descrambling device pre-downloads password data including the arbitrary password from the communication body, and the password mixed in the bitstream is A means for activating the descrambling device if it matches the password previously downloaded to the receiving terminal was used.

As the password data, at least a code for identifying the program, the password body, and a bitstream in which the number of times the password can be used are written, and if the password is searched a specified number of times from the program data, the password data is received by the receiving terminal. , And a means for deleting the password data from the receiving terminal when the time elapses.
Further, as the password data, a means of writing a format for identifying whether the written parameter is the number of times or time is also used.

The scramble referred to in the present invention is a structure in which data is encoded before transmission and decoded by the receiving terminal, but the data is compressed before transmission and the data received in a compressed state at the receiving terminal. Since the configuration for decompressing is also a function that is substantially equivalent to scrambling, it is defined as a concept including these techniques.

[0008]

The descrambling device provided in the receiving terminal has a function of descrambling the program data transmitted through the communication means which is a transmission system. Then, the descrambling device functions only when the password included in the previously downloaded password data and the password mixed in the program data match, and descrambles. In order to use the password written in the password data, you have to select from two types, the number of times limit and the time limit, but these limits prevent unauthorized use of pay data or use beyond the approval. Has an effect. The format for identifying whether the number of times is limited or the time is limited has a function of appropriately specifying whatever method the program data is transmitted.

[0009]

An embodiment of the present invention will be described below with reference to the accompanying drawings. First, in the present invention, password data is previously given from the transmission main body to the reception terminal, the security is confirmed using the content, and the descrambling device is operated for the first time by this. FIG. 1 shows the structure of password data that is the object of transmission according to the present invention. From the beginning, the data program name (program code) A to which the password is added, the password body B,
The password format C, the password holding time or the number of times D is configured as a data string, which is transmitted in the form of a bit stream. Of course, since this is a data string to be transmitted, a header and a footer are added to this data string to ensure the transmission reliability. Moreover, since it is assumed that the data is transmitted to a specific receiving terminal,
It also includes a technique of adding an identification code unique to the receiving terminal to a header or the like. Here, the password format C is a part that indicates whether the condition that the receiving terminal can process data using this password is a time limit or a number limit. In other words, if the designated program is transmitted at a specific time, it is preferable to limit the conditions under which the password can be used by time. on the other hand,
If the designated program has a nature of being transmitted irregularly, inconvenience will occur if the time is limited, so it is preferable to specify the number of times the password has been used. Which one is adopted can be appropriately selected according to the nature of program transmission. When the format C is a time limit, the password holding time is written in the data D, and when the number of times is limited, the holding count is written in the data D. Then, the number of times data is decremented each time the number of times processing is performed, and when the number of times becomes 0, all of the above data is deleted. In case of time limit, all data will be deleted as time passes.

The receiving terminal is equipped with a descrambling device such as a decoder or a decompressor. FIG. 2 is a block diagram of a scrambler in the receiving terminal. 1 is a CPU for controlling the main configuration of the receiving terminal, 2 is a data receiving device, 3 is a descrambling device, 4 is a RAM or EEP.
A memory area constituted by a ROM or the like and directly managed by the CPU 1, 5 is a processing device for descrambled program data and the like, and 6 is a large-scale storage device such as a hard disk which is appropriately used. Reference numeral 7 is an interface for connecting the CPU 1 and each device. The data receiving terminal 2 is provided with a tuner if the transmission means is wireless data communication such as satellite communication, a modem if the transmission line is an analog public line, and a network control device if the transmission line is a digital wired line or CATV line. It will be.

Here, when the overall configuration of the communication is outlined, the password data of FIG. 1 is previously transmitted from the transmission main body to the receiving terminal, and the CPU 1 identifies it through the data receiving device 2 in the receiving terminal. It is written in the memory area 4. The trigger for sending the password data from the transmitting body to the receiving terminal is achieved by the receiving terminal user requesting the desired program by another means. If the requested program is data to be transmitted in a predetermined time zone according to the program guide, etc., the transmission main body adds a time restriction code to the format C of the password data and further specifies the transmission time zone. Write to D and send. On the other hand, in the case of data which is not predetermined on-demand or how much time difference is transmitted after the request, a code for limiting the number of times is given to the format C, and the limited number of times is written to the data D. Send. This allows the receiving terminal to be ready to descramble.

Next, the same password as that previously transmitted to the receiving terminal is mixed and transmitted to the data body of the program or the like. When the transmission means is packet communication, a password is given to each packet. It is not necessary to limit the number of passwords to one data body, and a plurality of passwords can be mixed. In this case, if the password data format is a limited number of times, it is more reliable to write the number of times in the password data as many as the number of mixed passwords.

FIG. 3 is a flowchart showing a procedure for activating the descrambling device 3 in the receiving terminal. This flowchart is described as a configuration in which the receiving terminal can select a plurality of channels such as CATV and satellite communication, and shows the case where the receiving device 2 is a tuner. When the processing is started and the channel is selected by the receiving device 2 (11), the CPU 1 analyzes the data stream received from the channel (12), and retrieves the password previously transmitted and stored in the memory area 4 as a retrieval element. As a result, it is searched whether the same password exists in the data stream (13). Then, when the password does not exist, the data input to the descrambling device 3 is drained without being processed (14). On the other hand, when the same password is retrieved, the descrambling device 3 is activated under the control of the CPU 1 (15). This flow chart explains the case where the scramble data format is limited to the number of times of one. Since the number of times of the data D is decremented to 0, the password data stored in the memory area 4 is deleted (16). Then, the descrambling device 3 continues to be activated until the program to be received is completed (17), and the descrambling device 3 is stopped if the program end code is read or it is confirmed that the data input has disappeared for a certain time. Then, a series of operations is finished (18).

By the way, it is possible to mix a plurality of passwords in one program and terminate the processing when the passwords cannot be retrieved. In this case, in FIG. 3, if the program end code cannot be identified in block 17, the process immediately returns to immediately before block 12, and a series of flow for conducting the password search is constructed. Then, the password count of the password data held in advance is decremented once and becomes 0, but if the program end code is identified, the procedure is ended.

When the scramble data format is time-limited, the scramble data is deleted immediately after the set time elapses by the timer of the CPU 1 or the like.

In the above embodiment, it is premised that the transmitted program is a type of data that can be directly processed by descrambling. However, computer games and the like must temporarily hold data such as executable files inside the receiving terminal. Password data with a limited number of times is preferable for the processing in this case. Headers and footers are deleted from the scrambled bit stream for transmission, stored in the large-scale storage device 6 in the scrambled state, and the execution file can be descrambled once by one password search. To do. If how many times the password can be used is declared at the time of a download request from the transmission body of the password data, the number of times corresponding to the number of times is written in the data D of FIG. 1 and downloaded. Therefore, the usage fee can be easily calculated based on this number of times.

[0017]

According to the present invention, the descrambling device is downloaded for the first time if the password data including the password is downloaded from the transmission main body to the receiving terminal and the password contained in the program data transmitted later is searched and the passwords match. Since it was decided to activate, it is possible to safely transmit even pay data, and it is possible to more securely avoid unauthorized use of data as compared with the conventional case. Also, considering that program data may be sent at a predetermined time slot or may be sent on demand at irregular intervals, select and specify the password search frequency limit and time limit. Therefore, it is possible to appropriately support various transmission modes, and it is possible to greatly widen the range of use.

[Brief description of drawings]

FIG. 1 is a block diagram showing an example of a password data string adopted in the present invention,

FIG. 2 is a block diagram of a main part of a receiving terminal,

FIG. 3 is a flowchart showing a processing procedure in a receiving terminal.

[Explanation of symbols]

 A data program name (program code) B password body C password format D data string 1 CPU 2 data receiver 3 scrambler 4 memory area 5 processor 6 large scale memory 7 interface

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Claims (4)

[Claims] 1. A transmission main body having a plurality of program data and a receiving terminal are connected by an arbitrary communication means, and the program data is scrambled through the communication means and is received as a bit stream in which arbitrary passwords are mixed. In a device for transmitting to a terminal, the receiving terminal has a receiving device and a descrambling device, the descrambling device is pre-downloaded from the communication body password data including the arbitrary password,
A data scrambler that activates the descrambling device if the password mixed in the bitstream matches the password previously downloaded to the receiving terminal. 2. The password data is at least a code for identifying a program, a password body, and a bitstream in which the number of times the password can be used is written. If the password is searched a specified number of times from the program data, the password data is obtained. The data scramble device according to claim 1, which is deleted from a receiving terminal. 3. The password data is a bitstream in which at least a code for identifying a program, a password body, and a time during which the password can be used are written, and the password data is deleted from the receiving terminal when the time has elapsed. 1. A data scrambler according to 1. 4. The data scramble device according to claim 2, wherein the password data is written in a format for identifying whether the parameter written is the number of times or time.