JPH11163851A - Information transmission method and its system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information transmission method and its system where a degree of freedom of security of encryption is high. SOLUTION: An information unit descrambler 134 receives an encryption information unit Iue outputted from a demultiplexer 133, decodes the encryption once and outputs an encrypted information unit Iue. The information unit descrambler 134 receives again the encrypted information unit Iue outputted by itself again to decode the encryption repetitively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a method and an apparatus for encrypting and transmitting information in computer communication and data broadcasting.

[0002]

2. Description of the Related Art FIG. 25 shows a conventional information transmission apparatus.
The information transmission device 1900 includes a transmission unit 1910 and a transmitter 1
920 and a receiving unit 1930. Hereinafter, two different specific examples will be described using information transmission on the Internet as example 1 and digital broadcasting as example 2. Note that a plurality of receiving units can correspond to one transmitting unit.

[0003] A transmitting unit 1910 performs multiplexing or encryption on the information unit Iu to generate and output transmission information It. Here, the information unit Iu is a group of electronic data that is meaningful to the user, such as text information, audio information, still image information, moving image information, HTML (H
hypertext Makeup Language)
Information or a composite of them.

(Transmitter 1910) The transmitter 1910 includes an information unit generator 1911, a multiplexer 1912, a lower layer scrambler 1913, and a transmitter 1914.
The information unit generator 1911 generates and outputs a plurality of information units Iu. In Example 1, an information unit Iu obtained by a user inputting a text sentence from a keyboard or the like or taking an image into a computer, or an information unit Iu already stored in a computer is output. The information unit generator 1911 is, for example, an input screen portion of e-mail software or a server of a broadcasting station on the Internet.

[0005] On the other hand, in Example 2, a method is conceivable in which all information units Iu to be generated are stored in advance in the information unit generator 1911, and are simply selectively output according to a predetermined schedule. Information unit generator 1911
Is a program operation management system in a digital broadcast transmission system, a VTR cart machine, an MPEG-2 encoder, and a digital broadcast EPG (Electric).
This is a broadcasting station system including a Program Guide management transmission system. However, since additional information such as EPG needs to be continuously transmitted for a long time, the same content is repeatedly output in the information unit generator 1911 at a cycle of the order of seconds.

The multiplexer 1912 receives the information unit Iu output from the information unit generator 1911, multiplexes the plurality of input information units Iu, and multiplexes the multiplexed information unit Iu.
Is output as multiplexed information Im. With this multiplexing,
The plurality of information units Iu are converted in transmitter 1920 into a format suitable for efficient transmission.

In Example 1, a multiplexer 1912
Is, for example, MIME (Multiti) used to send multimedia information in Internet e-mail.
-Purpose Internet Mail Ex
tensions). In this case, the multiplexer 1912 converts each of the plurality of information units Iu such as text information, image information, audio information, and the like into each part, converts the plurality of parts into a multi-part message conforming to MIME, and outputs the message. . MI
The formal specification of ME is RFC (Request for
Comments) 1521/1522.

On the other hand, in Example 2, the multiplexer 19
12 is, for example, MPEG data from plural stream data.
-2 System TS (Transport Stream)
m). In addition, MPEG
-2 system and TS are ISO / IEC CD 1
3818-1. In this case, the multiplexer 1912 converts each of the plurality of information units Iu output from the information unit generator 1911 into a PES (Packetize).
The packet is divided into packets called “ed Elementary Stream”, and the obtained packets are multiplexed based on a predetermined rule.

The lower layer scrambler 1913 receives the multiplexed information Im output from the multiplexer 1912, encrypts the multiplexed information Im according to a predetermined encryption algorithm, and converts the encrypted multiplexed information Im into an encrypted multiplexed information unit Im.
Output as e. In Example 1, the lower layer scrambler 1913 is a software PGP (Pretty Good Good) that implements, for example, an RSA encryption that is a public key encryption.
Privacy) with the encryption option.

[0010] The output of the lower layer scrambler 1913 is the text of the e-mail encrypted by the RSA encryption. Regarding the RSA encryption, R.I.
L. Rivest, A .; Shamir, L .; Adlem
"A Method for Obta
ining Digital Signaturesa
nd Public Key Cryptosystem
ms ”(Communicati published in February 1978)
ons of the ACM, Vol. 21, No. 2). Simson for PGP
Garfinkel, PGP: Pretty Go
Od Privacy "(O'Reilly & As
sociates).

On the other hand, in Example 2, the lower layer scrambler 1913 is, for example, a transport layer scrambler. The lower layer scrambler 1913 receives the input M
The payload part of the PEG-2 TS is defined as Multi-2 or DES (the DataEncryption St.).
and an encrypted MPEG-2 TS that is the result of the encryption. Note that MULTI-2 was developed by Hitachi, Ltd. for the developed digital broadcasting system.

The transmitter 1914 is provided with the lower layer scrambler 1
The encrypted multiplex information unit Ime input from 913 is converted into transmission information It. This transmission information It is transmitted to the transmitter 192.
0 is transmitted. In the first example, the sending unit 1914 is a program for adding a mail header including a destination field, a sender field, and the like to the body of an electronic mail. This mail header is added to the e-mail output from the sending unit 1914. On the other hand, Example 2
In, the transmitter 1914 is a modulator and error correction encoder for MPEG-2 TS.

(Transmitter 1920) The transmitter 1920 transmits input transmission information It to a physically distant point.
The input and output of the transmitter 1920 are both transmission information It. All the inputs of the transmitter 1920 are error-free and the receiving unit 193
It need not appear in the output to zero. In Example 1, the transmitter 1920 is a mail transmission protocol SMTP connected to each other by a communication path such as the Internet.
(Simple Mail TransferProt
ocol) are interpreted and executed. Send as a typical mail communication daemon
mail.

The formal specification of SMTP is RFC 82
1, RFC 822, and RFC 974. As for sendmail, E.I. All
"" SENDMAIL-An Int
erworkwork Mail Router "Un
ix Programmer's manual "(C
SRG U.S. C. Berkeley, published July 1983).

On the other hand, in Example 2, the transmitter 1920
Is composed of an up-converter, a parabolic antenna for transmitting data to a satellite, a communication satellite, and a ground receiving antenna.

(Reception unit 1930) The reception unit 1930 receives the transmission information It transmitted from the transmitter 1920,
The information unit Iu is presented to the user. The receiving unit 1930
A receiver 1931, a lower layer descrambler 1932,
It includes a demultiplexer 1933, a regenerator 1934, a memory 1935, and a presenter 1936.

(Reception unit 1930) The receiver 1931 extracts all or a part of the transmission information It input from the transmitter 1920, and obtains and outputs an encrypted multiplexed information unit Ime from the extracted transmission information It. In Example 1, receiver 1931 is a front-end program for mail transmission. On the other hand, in Example 2, the receiver 1931 connects a satellite broadcast tuner, a demodulator, and an error correction complex.

The lower layer descrambler 1932 decrypts the encrypted multiplex information unit Ime output from the receiver 1931 and reproduces the multiplex information Im. In Example 1, the lower-layer descrambler 1932 starts the PGP program with the option of decryption. On the other hand, in Example 2, the lower layer descrambler 1932 is a descrambler of the transport layer.

The demultiplexer 1933 has the multiplex information I
The information unit Iu is separated from the m and extracted for each information unit Iu, and the extracted information unit Iu is output. In Example 1, the demultiplexer 1933 is a MIME decoder, and separates and extracts text information, image information, and the like, which are each part included in a multipart message, separately. On the other hand, in Example 2, the demultiplexer 1933 is a demultiplexer of the MPEG-2 TS. The demultiplexer 1933 uses the MPEG-2
Separate a plurality of streams multiplexed by the system.

The regenerator 1934 includes a demultiplexer 19
Receiving the information unit Iu from 33, it generates reproduction information Ir that is reproducible information. In Example 1, the reproducer 1934 is a text file viewer, image file presentation software, or the like. On the other hand, in Example 2, the reproducer 1934 is, for example, an MPEG-2 decoder that reproduces audio and images encoded by MPEG-2.
In this case, the output is NTSC (National Tel)
evolution System Standard C
ommitter signal) and an analog audio signal.

The storage 1935 receives the input of the reproduction information Ir from the reproducer 1934, stores the first reproduction information Ir1, and stores the first reproduction information Ir1 stored in accordance with the reproduction request into the second reproduction information Ir1. Is output as reproduction information Ir2. Hereinafter, this operation is simply referred to as “reproduction”. As will be described in detail later, the first reproduction information Ir1 and the second reproduction information Ir2 have the same contents but different presentation times.

In the first embodiment, the storage 1935 is, for example, an OS (Operating System) file system or electronic mail classification management software. On the other hand, in Example 2, the storage unit 1935 records and reproduces, for example, NTSC signals and analog audio.
(Video tape recorder) and VCR (video cassette recorder).

The presenter 1936 receives the first reproduction information Ir1 input from the reproducer 1934 and the second reproduction information Ir2 input from the storage 1935, and presents one or both of them to the user. I do. In Example 1, the presenter 1936 is, for example, an X-windows or Microsoft W
Windows system such as Windows. On the other hand, in Example 2, the presentation device 1936
This is a television receiver which receives and receives a C signal and an analog audio signal.

FIG. 26 shows an example of an encrypted multiplexed information unit Ime0d generated by the information transmission apparatus 1900. In this example, the encrypted multiplexed information unit Ime0d
Includes four information units Iu1d, Iu2d, Iu3d, and Iu4d, each indicated by a circle in FIG. The wavy rectangles represent the information units Iu1d, Iu2d, Iu
3d and Iu4d represent encrypted multiplexed information obtained by encrypting the lower layer scrambler 1913 only once. That is, the information units Iu1d, Iu2d, Iu3d,
And Iu4d are all encrypted with the same cipher and protected at the transport level with a single cipher.

The information units Iu1d, Iu2d, Iu3d,
And Iu4d represent a sightseeing guide, a sightseeing spot weather forecast, a nationwide weather forecast, and a district weather forecast, respectively, in consideration of the weather forecast. By encrypting the subtitles related to these weather forecasts, a total weather forecast program Iue is generated. As described above, from the viewpoint of encryption, there is no hierarchical relationship between these subtitles.

(Operation) Referring to FIGS. 27 and 28,
The operation of the conventional information transmission apparatus 1900 will be described below. FIG. 27 is a flowchart showing the operation of the transmitting unit 1910 and the transmitter 1920.

In step S2001, the information unit generator 1911 generates and outputs a plurality of information units Iu. The information unit Iu may be generated in the method in Example 1 in which the user inputs or designates a file, or in the example 2 in which the information unit Iu is selectively output from the stored information unit Iu according to a predetermined schedule.

In step S2002, the multiplexer 1912 multiplexes the information unit Iu generated in step S2001, and outputs the result as multiplexed information Im. The multiplex information Im is MIME-based multi-part data in Example 1, and in Example 2, MPEG-
This is data of TS of two systems.

In step S2003, step S
The multiplexed information Im obtained by multiplexing in 2002 is encrypted by the lower layer scrambler 1913, and the encrypted multiplexed information unit Ime
Generate The multiplex information Im is encrypted by the RSA encryption or the like in Example 1, and the MPEG-
The TS-2 payload part is Hitachi's Multi-2
It is encrypted by encryption.

In step S2004, the transmitter 19
14 converts the encrypted multiplexed information unit Ime obtained in step S2003 into a format that can be transmitted by the transmitter 1920 or is suitable for transmission to generate transmission information It. In Example 1, information such as a To: field and a From: field added to the head of the mail body, which is the encrypted multiplexed information unit Ime, is output as transmission information It. On the other hand, in Example 2, after the MPEG-2 TS is encoded with an error correction code, the modulated TS is output.

In step S2005, the transmitter 19
20 transmits the transmission information It to a physically distant point. In Example 1, a mail communication daemon mounted on one or a plurality of connected computers uses the Internet or a LAN (Locala) based on the protocol SMTP.
l Area Network)
By communicating with the network, mail is transmitted from the mail communication daemon on one computer to the mail communication daemon on the other computer.

On the other hand, in Example 2, the transmission information It converted by the up-converter is transmitted to the communication satellite by the parabolic antenna, and the communication satellite transmits the transmission information It received by the transponder to the ground. Then, the transmission information It from the communication satellite is received by the receiving antenna on the ground.

Next, referring to FIG.
Will be described. In FIG. 28, transmission information It
The operation in which the information unit Iu is extracted in real time from among them and presented to the user, stored as needed by the user, and re-viewed later is shown in detail.

In step S2101, when the user views the information unit Iu in real time from the transmission information It, the process proceeds to step S2102. The user
When viewing the information unit Iu stored in the storage 1935 in advance, the process proceeds to step S2109.

In step S2102, the receiver 19
Reference numeral 31 extracts part or all of the encrypted multiplex information unit Ime from the transmission information It input from the transmitter 1920. In Example 1, a process of extracting one piece of electronic mail data addressed to a specific user is performed. On the other hand, in Example 2,
A specific packet in which information to be obtained by tuning to a predetermined frequency is stored is referred to as a PID (Packet ID).
Is performed to perform filtering and selective extraction.

In step S2103, the lower layer descrambler 1932 decrypts the encrypted multiplex information unit Ime input from the receiver 1931, and
Output m. In Example 1, the lower-layer descrambler 1932 starts the PGP program with the option of decryption. By the program of PGP, R
The decryption of the SA code is performed and the decryption result is output. on the other hand,
In Example 2, the multiplex information Im encrypted by the Multi-2 encryption is decrypted to obtain the multiplex information Im.

In step S2104, the demultiplexer 1933 separates and extracts the multiplexed information unit Im for each information unit Iu. In Example 1, the demultiplexer 1933 separates a multi-part message multiplexed based on MIME for each part. As a result, text information, image information, audio information, and the like, which are each part, are separated as a separate information unit Iu. On the other hand, in Example 2, the demultiplexer 1933 is
A plurality of streams multiplexed by the PEG-2 system are separated based on a PID (Packet ID, packet identifier). As a result, additional information such as an MPEG-2 video stream, an MPEG-1 audio stream, and an EPG is separated as a separate information unit Iu. However, MPEG-2 video is compliant with ITU-TH. 262
The audio of MPEG-1 is ISO / IEC 11172.
-3 standardized.

In step S2105, the regenerator 19
34 is an information unit I output from the demultiplexer 1933
u is input to generate reproduction information Ir that is reproducible information.

In Example 1, for example, when the information unit Iu is text information, a font corresponding to each character code is selected and enumerated to generate a bitmap format, and the first reproduction information Ir1 Generate as Also,
JPEG (Joint Photographics)
In the case of an image information format such as Experts Group), the result of development into a bitmap format is output as reproduction information Ir1. However, JPEG is ISO
/ IEC10918 standardized. In the case of audio information, the audio information is converted into an analog audio signal by a function equivalent to that of a D / A converter and output as reproduction information Ir.

On the other hand, in Example 2, step S210
If the information unit Iu obtained in step 4 is an MPEG-2 video stream, decoding of the MPEG-2 video is performed, and an NTSC signal is output as reproduction information Ir.
In the case of an audio stream, D is added to the analog audio signal.
/ A conversion and output.

In step S2106, the presentation device 19
36 presents the first reproduction information Ir1 obtained in step S2105 to the user according to the format of the reproduction information.
In Example 1, when the reproduction information obtained in step S2105 is in the form of a bitmap, the presenter 1936 arranges and presents the reproduction information Ir on the display screen and visually presents it to the user. If the reproduction information Ir1 obtained in step S2105 is an analog audio signal, the analog audio signal is converted into sound by sending the reproduction information Ir1 to a speaker, and is presented audibly to the user.

On the other hand, in Example 2, step S210
The NTSC signal of the reproduction information Ir obtained in step 5 is received on a display, the analog audio information is sent to a speaker, and the reproduction information Ir is presented to the user.

If it is determined in step S2107 that the information in the current transmission information It is desired to be stored based on the user's intention, the process proceeds to step S2108; otherwise, the process proceeds to step S2101. Specifically, the user's intention presentation includes a case where the user's intention is specified while watching the program, and a case where the user's intention is preset by a timer or the like.

In step S2108, step S
The reproduction information Ir generated in 2105 is stored in the storage unit 1935. Thereafter, processing proceeds to step S2101.
The reproduction information Ir1 may be additionally stored in the storage device 1935, or may overwrite already stored information. Alternatively, if the old version information is already stored in the storage device 1935, the old version information may be exchanged. In Example 1, the reproduction information Ir is stored and organized in the file system. Information unit I
u is arranged, for example, by arrival order, by sender, and by topic. On the other hand, in Example 2, reproduction information Ir such as video and audio is recorded on a video tape or the like. For example, N
Additional information other than video and audio multiplexed in the vertical erasure section of the TSC may be stored at the same time. When recording digital information as it is, a plurality of streams other than video and audio may be recorded simultaneously.

In step S2109, the storage device 19
35 outputs the stored first reproduction information Ir1 as second reproduction information Ir2. In Example 1, the reproduction information Ir2 (Ir1) selected by the user is output from the reproduction information Ir1 arranged and stored in the file system. On the other hand, in Example 2, video and audio are reproduced from a video tape or the like. The selection of the reproduction information Ir that the user wants to select may be automated by realizing it as a function of the storage unit 1935, or the user may select a video tape or the like and set it in the storage unit 1935.

In step S2110, the presenter 19
36 is the reproduction information Ir output in step S2109.
Is presented to the user. Thereafter, the process proceeds to step S210
Return to 1. The operation in step S2110 may be the same as the operation in step S2106 except for returning to step S2101.

[0047]

However, as described above, the information transmission device 1900 has the following two main problems. First, as a first problem, there is a limit on the degree of freedom of the encryption strength. In general, the higher the strength of a cipher against unauthorized decryption, the more resources such as computer resources and processing time are required for decryption processing by a legitimate decryption method. For this reason, it is required to perform encryption with sufficient strength as necessary according to the confidentiality required for the object to be encrypted.

For example, a partial information unit I of information to be transmitted
When it is necessary to perform more confidential encryption on u, it is necessary to perform stronger encryption on some information units Iu. For example, in a weather forecast program, nationwide weather forecasts are not encrypted for free, detailed district forecasts are paid, and custom-made weather forecasts for each user are also separate charges. Also, custom weather forecasts need to be encrypted with higher confidentiality than detailed district forecasts. In theory, in many ciphers, the strength of the cipher can be adjusted by increasing the size of the decryption key. However, due to restrictions on commonly used decryption hardware, it is not always possible to say that there is sufficient freedom in the strength of encryption.

The use of decryption hardware with a high degree of freedom in encryption has disadvantages such as a complicated receiving section and the need to prepare special hardware. Also, information units Iu having different encryption strengths
If the key is changed every time, in the worst case, encryption and decryption are performed for each information unit Iu, which is not efficient.

The second problem is that it is necessary to decrypt the code before storing. Generally, when sending paid information on media that can be accessed by everyone, such as broadcasting, the transmitting unit transmits the information in an encrypted state, and the receiving unit charges the fee when the information is decrypted. Often do. This is to prevent unauthorized viewing of a user who has not paid a fee.

The conventional information transmission apparatus 1900 includes a transmitting unit 1
When the information unit Iu sent from the 910 is viewed in a short time after transmission, not in real time, the reproduction information Ir that has been decrypted in advance by the lower layer descrambler 1932 is stored. Here, a case is considered in which an information unit Iu that may be viewed is stored in advance and viewed later. If an information unit Iu that may be viewed later is stored in a large amount, an information unit Iu that will not be viewed eventually occurs even if the encryption is decrypted, and the user is charged at the same time as the descrambling performed during storage. If this is the case, it is disadvantageous for the user.

Conversely, if the information unit Iu is stored in a small amount so as to be carefully selected for later viewing, it cannot be viewed because the user does not store it later even if he or she wants to view it. This is because it is generally very difficult for the user himself to determine in advance which information unit Iu to view later.

On the other hand, a method of changing the configuration of the receiving unit and storing the transmission information as it is can be considered. However, in this method, additional information such as an EPG to which the same thing is repeatedly sent is stored redundantly, the number of survivors in an airplane accident, software that is frequently upgraded, etc.
Since the information unit Iu, which is valuable only for the latest one, is stored including the old and new ones, it is not practical to waste the capacity of the storage device, or extra processing is required when extracting the latest one.

[0054]

Means for Solving the Problems and Effects of the Invention The present invention has been made to solve the above problems. A first invention is an information transmission apparatus used in an information transmission system for communicating between at least two parties encrypted information composed of a plurality of information units hierarchically encrypted and multiplexed, wherein the information is: An information unit generator that is encrypted for transmission and generates an information unit, a first encryptor that encrypts the information unit with a first encryption method and generates an encrypted information unit; An information transmission apparatus comprising: a first multiplexer that multiplexes at least one of an information unit and an encrypted information unit to generate a multiplexed information unit. As described above, in the first invention, it is possible to generate encrypted information including a plurality of information units hierarchically encrypted and multiplexed in various combinations. According to a second aspect, in the first aspect, a second encryptor for encrypting the multiplexed information by a second encryption method to generate encrypted multiplexed information, and multiplexing the encrypted information unit to generate the multiplexed information. The apparatus further includes a second multiplexer for generating.

As described above, in the second invention, since each of the information units can be encrypted by different encryption methods, it is possible to guarantee the resistance to the illegal decryption of the encryption.

A third invention according to the second invention, further comprises a third encryptor for encrypting the multiplexed information by a third encryption method to generate encrypted multiplexed information.

According to a fourth aspect, in the third aspect, the third aspect is provided.
Is the same as that used for the encrypted information.

According to a fifth aspect, in the third aspect, the second aspect is provided.
Is the same as the third encryption method.

According to a sixth aspect, in the third aspect, the first, second, and third encryption methods are the same.

According to a seventh aspect based on the first aspect, the apparatus further comprises a transmitter for converting the encrypted multiplexed information into a format suitable for efficient transmission.

According to an eighth aspect, in the first aspect, the first aspect is provided.
Is characterized in that an information unit is encrypted by an encryption method suitable for transmitting information.

A ninth invention is an information transmission apparatus used in an information transmission system for communicating between at least two parties encrypted information composed of a plurality of information units that are hierarchically encrypted and multiplexed, A first decryptor for decrypting the encrypted information by a first decryption method to generate a first multiplexed information unit, and a first decryption unit for demultiplexing the first multiplexed information unit to obtain a first encrypted information unit; A second demultiplexer for generating any one of the two multiplexed information units and the information unit, and an information unit or the second encrypted information obtained by decoding the first encrypted information unit by the second decoding method. A second decoder for generating units is provided. First
In a ninth aspect of the present invention, in the ninth aspect, a second demultiplexer for demultiplexing the second multiplexed information, and a second decryption method for decrypting the second encrypted information unit to convert the information unit And a third decryptor for generating. In an eleventh aspect based on the ninth aspect, the first decryption method is the same as that used for the encrypted information. A twelfth invention according to the first invention, further comprising a storage device provided between the first demultiplexer and the second decryption device for storing the first and second encrypted information units. .

According to a thirteenth aspect, in the twelfth aspect,
A request to input the encrypted information unit from the second decryptor to generate reproduction information indicating the content of the encrypted information and to supply the encrypted information stored in the storage device to the second decryptor. And a regenerator for performing the operation.

A fourteenth invention is an information transmission method used in an information transmission system for communicating encrypted information comprising a plurality of information units hierarchically encrypted and multiplexed between at least two parties, The information is encrypted for transmission, and an information unit generating step of generating an information unit, and the information unit is encrypted by a first encryption method.
The method includes an encryption step of generating an encrypted information unit, and a multiplexing step of multiplexing at least one of the information unit and the encrypted information unit to generate a multiplexed information unit. As described above, in the fourteenth invention, it is possible to generate encrypted information including a plurality of information units that are hierarchically encrypted and multiplexed with each other in various combinations. In a fifteenth aspect based on the fourteenth aspect, an encryption step of encrypting the multiplexed information by the second encryption method to generate encrypted multiplexed information, and multiplexing the encrypted information unit to generate a multiplexed information unit. The method further includes a multiplexing step.

As described above, in the fifteenth aspect, each of the information units can be encrypted by a different encryption method, so that it is possible to guarantee the resistance to unauthorized decryption of the encryption.

According to a sixteenth aspect, in the fifteenth aspect,
The method further includes an encryption step of encrypting the multiplexed information with a third encryption method to generate encrypted multiplexed information.

According to a seventeenth aspect, in the sixteenth aspect,
The third encryption method is the same as that used for the encryption information.

According to an eighteenth aspect, in the sixteenth aspect,
The second encryption method is the same as the third encryption method.

According to a nineteenth aspect, in the sixteenth aspect,
The first, second, and third encryption methods are the same.

According to a twentieth aspect, in the fourteenth aspect,
The method further includes a conversion step of converting the encrypted multiplexed information into a format suitable for efficient transmission.

According to a twenty-first aspect, in the fourteenth aspect,
In the encryption step, the information unit is encrypted by an encryption method suitable for transmitting information.

A twenty-second invention is an information transmission method used in an information transmission system for communicating encrypted information comprising a plurality of information units hierarchically encrypted and multiplexed at least between two parties, A first decryption step for decrypting the encrypted information by a first decryption method to generate a first multiple information unit, wherein the information is encrypted for transmission, and A demultiplexing step of demultiplexing to generate one of a first encrypted information unit, a second multiplexed information unit, and an information unit, and decrypting the first encrypted information unit by a second decryption method Information unit or second
An information transmission method comprising a second decryption step of generating an encrypted information unit.

According to a twenty-third aspect, in the twenty-second aspect,
The method further includes a second demultiplexing step of demultiplexing the second multiplexed information, and a third decryption step of decrypting the second encrypted information unit by a third decryption method to generate an information unit. .

The twenty-fourth invention is the twenty-second invention, wherein
The first decryption step is the same as that applied to the encrypted information.

According to a twenty-fifth aspect, in the fourteenth aspect,
The method further includes storing the first and second encrypted information units.

According to a twenty-sixth aspect, in the twenty-fifth aspect,
A request to input the encrypted information unit from the second decryptor to generate reproduction information indicating the content of the encrypted information and to supply the encrypted information stored in the storage device to the second decryptor. The reproducing step is further provided.

A twenty-seventh aspect of the present invention is an information transmission system for at least two parties communicating encrypted information comprising a plurality of information units hierarchically encrypted and multiplexed, wherein the information is used for transmission. And an information unit generator for generating an information unit, and a first unit for encrypting the information unit with a first encryption method to generate an encrypted information unit.
, A first multiplexer for multiplexing at least one of the information unit and the encrypted information unit to generate a multiplexed information unit, and a first decryption device for decrypting the encrypted information by a first decryption method. And a first decryptor for generating the first multiplexed information unit, and demultiplexing the first multiplexed information unit to generate one of a first encrypted information unit, a second multiplexed information unit, and an information unit. An information transmission apparatus comprising: a first demultiplexer; and a second decryptor that decrypts the first encrypted information unit by a second decryption method to generate an information unit or a second encrypted information unit.

As described above, according to the twenty-seventh aspect, it is possible to generate encrypted information composed of a plurality of information units that are hierarchically encrypted and multiplexed with each other in various combinations. The multiplexed information can be reproduced. In a twenty-eighth aspect based on the twenty-seventh aspect, a second encryptor that encrypts the multiplexed information by a second encryption method to generate encrypted multiplexed information and multiplexes the encrypted information unit to generate the multiplexed information. The apparatus further includes a second multiplexer for generating.

As described above, in the twenty-eighth aspect, each of the information units can be encrypted by a different encryption method, so that the resistance to illegal decryption of the encryption can be guaranteed.

A twenty-ninth aspect of the present invention is based on the twenty-eighth aspect,
The information processing apparatus further includes a third encryptor that encrypts the multiplexed information using a third encryption method to generate encrypted multiplexed information.

According to a thirtieth aspect, in the twenty-ninth aspect,
The third encryption method is the same as that used for the encryption information.

According to a thirty-first aspect, in the twenty-ninth aspect,
The second encryption method is the same as the third encryption method.

[0083] A thirty-second aspect is the twenty-ninth aspect, wherein
The first, second, and third encryption methods are the same.

According to a thirty-third aspect, in the twenty-seventh aspect,
The apparatus further includes a transmitter for converting the encrypted multiplexed information into a format suitable for efficient transmission.

A thirty-fourth invention is the invention according to the twenty-seventh invention, wherein
The first encryptor encrypts the information unit by an encryption method suitable for transmitting information.

[0086] A thirty-fifth invention is a method according to the twenty-seventh invention, wherein
It further includes a second demultiplexer for demultiplexing the second multiplexed information, and a third decryptor for decrypting the second encrypted information unit by a third decryption method to generate an information unit. .

[0087] In a thirty-sixth aspect, based on the twenty-seventh aspect,
The first decryption method is the same as that used for the encrypted information.

A thirty-seventh aspect is based on the twenty-seventh aspect,
There is further provided a storage device provided between the first demultiplexer and the second decryption device for storing the first and second encrypted information units.

A thirty-eighth aspect of the present invention is the thirtieth aspect, wherein
A request to input the encrypted information unit from the second decryptor to generate reproduction information indicating the content of the encrypted information and to supply the encrypted information stored in the storage device to the second decryptor. And a regenerator for performing the operation.

[0090]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (First Embodiment) FIGS.
An information transmission device according to the first embodiment of the present invention will be described with reference to FIG. Hereinafter, two different specific examples will be described using information transmission on the Internet as example 1 and digital broadcasting as example 2. The information transmission device 100 includes a transmission unit 110, a transmitter 120
And a receiving unit 130.

(Transmission Unit 110) The transmission unit 110 includes an information unit generator 111, an information unit scrambler 112, a multiplexer 113, a lower layer scrambler 114,
A transmitter 115 is included. The information unit generator 111 generates and outputs a plurality of information units Iu. In Example 1, the information unit generator 111 outputs an information unit Iu obtained by a user inputting a text sentence from a keyboard or the like or importing an image into a computer, or an information unit Iu already stored in the computer. Output. Information unit generator 111
Is, for example, an input screen portion of e-mail software or a server of a broadcasting station on the Internet.

On the other hand, in Example 2, a method is conceivable in which all information units Iu to be generated are stored in advance in the information unit generator 111, and are simply selectively output according to a predetermined schedule. Information unit generator 111
Is a program operation management system in a digital broadcast transmission system, a VTR cart machine, an MPEG-2 encoder, and a digital broadcast EPG (Electric).
This is a broadcasting station system including a Program Guide management transmission system. However, since additional information such as EPG needs to be continuously transmitted for a long time, the same unit is often repeatedly output in the information unit generator 111 at a cycle on the order of seconds.

The information unit scrambler 112 is connected to the information unit generator 111 and encrypts the input information unit Iu. The information unit scrambler 112 outputs the encryption result as an encrypted information unit Iue. One encryption target is an information unit Iu or a set having the encryption result as an element. The encryption information unit Iue is defined as follows. Definition 1. The encrypted information unit Iue is an information unit Iu. Definition 2. A set of the information unit Iu or the encrypted information unit Iue is the encrypted information unit Iue. Definition 3. What encrypted the encrypted information unit Iue is the encrypted information unit Iue.

The multiplexer 113 is connected to the information unit generator 111 and the information unit scrambler 112 and receives the information unit Iu and the encrypted information unit Iue, respectively. Then, the multiplexer 113 includes the information unit generator 111 and / or the information unit scrambler 112.
Is multiplexed, and the result obtained by the multiplexing is output as a multiplexed information unit Im. The multiplexer 113 is further connected to its own output port, receives the input of the multiplex information unit Im generated by itself, and multiplexes the multiplex information unit Im again. Further, an output port of the multiplexer 113 is also connected to an input port of the information unit scrambler 112 so that the information unit scrambler 112 can encrypt the multiplexed information unit Im to generate an encrypted information unit Iue. I have.

As described above, the multiplexer 113 handles the encrypted information unit Iue output from the information unit scrambler 112 as a multiplexing target, like the information unit Iu output from the information unit generator 111. The encrypted information unit Iue handled at one time by the information unit scrambler 112 is handled assuming that it is equal to the information unit Iu. The multiplexer 113 includes the information unit generator 1
The information unit Iu output from the information unit 11 is loaded on the encrypted information unit Iue output from the information unit scrambler 112 and multiplexed.

More specifically, the multiplexer 113 includes a plurality of information units Iu output from the information unit generator 111.
Then, the information unit Iu is multiplexed, and the multiplexed, that is, the structured encrypted information unit Iue is output as the multiplexed information unit Im. By multiplexing, the plurality of information units Iu are converted in the transmitter 120 into a format (multiplex information unit Im) suitable for efficient transmission.

In Example 1, the multiplexer 113
For example, MIME (Multi-p) used to send multimedia information by e-mail on the Internet
urpose Internet Mail Exte
nsions) of encoders. In this case, the multiplexer 113 converts each of a plurality of information units Iu, such as text information, image information, and audio information, into a part and converts the plurality of parts into a MIME-compliant multi-part message. Output. M
The formal specification of IME is RFC (Request for
Comments) 1521/1522.

On the other hand, in Example 2, the multiplexer 11
3 is, for example, MPEG-
Two-system TS (Transport Stream)
m). In addition, MPEG
-2 system and TS are ISO / IEC CD 1
3818-1. In this case, the multiplexer 113 converts each of the plurality of information units Iu output from the information unit generator 111 into a PES (Packetized).
The packet is divided into packets called elementary streams, and the obtained packets are multiplexed based on a predetermined rule.

The lower layer scrambler 114 is connected to the multiplexer 113 and encrypts the input multiplex information unit Im. And the lower layer scrambler 1
14 outputs the encryption result as an encrypted multiplex information unit Ime. In other words, the lower layer scrambler 114 receives the multiplexed information unit Im
Is encrypted according to a predetermined encryption algorithm, and the encryption result is output as an encrypted multiplex information unit Ime.

In Example 1, the lower layer scrambler 11
Reference numeral 4 denotes software PGP (Pretty Good Priv) that implements, for example, RSA encryption that is public key encryption.
acy) with the encryption option.
The output of the lower-layer scrambler 114 is the text of the e-mail encrypted by the RSA encryption. Regarding the RSA encryption, R.I. L. Rivers
t, A. Shamir, L .; A paper by Adleman entitled "A Method for Obtaining D"
digital Signatures and Pub
like Key Cryptosystems "(197
Communications of February 2008
The ACM, Vol. 21, No. 2) is described in detail. About PGP, Simson Garfink
El PGP: Pretty Good Private
cy "(O'Reilly & Associate)
s).

On the other hand, in Example 2, the lower layer scrambler 1913 is, for example, a transport layer scrambler. The lower layer scrambler 1913 receives the input M
The payload part of the PEG-2 TS is defined as Multi-2 or DES (the DataEncryption St.).
and an encrypted MPEG-2 TS that is the result of the encryption. Note that MULTI-2 was developed by Hitachi, Ltd. for the developed digital broadcasting system.

The sending device 1914 is connected to the lower layer scrambler 1
The encrypted multiplex information unit Ime input from 913 is converted into transmission information It. This transmission information It is transmitted to the transmitter 192.
0 is transmitted. In the first example, the sending unit 1914 is a program for adding a mail header including a destination field, a sender field, and the like to the body of an electronic mail. This mail header is added to the e-mail output from the sending unit 1914. On the other hand, Example 2
In, the transmitter 1914 is a modulator and error correction encoder for MPEG-2 TS.

(Transmitter 120) The transmitter 120 transmits the transmission information It input from the transmitter 115 to a physically distant point. The input and output of the transmitter 120 are both transmission information It. Not all of the inputs of the transmitter 120 need appear at the output to the receiver 130 without error. In Example 1, the transmitters 120 are connected to each other by a communication path such as the Internet, and the mail transmission protocol S
MTP (Simple Mail Transfer)
Protocols) are a plurality of mail communication daemons that interpret and execute the protocol. An example of a typical mail communication daemon is sendmail.

The formal specification of SMTP is RFC 82
1, RFC 822, and RFC 974. As for sendmail, E.I. All
"" SENDMAIL-An In
network Mail Router "U
ix Programmer's manual "
(CSRG U.C. Berkeley, July 1983)
Monthly issue). On the other hand, in Example 2, the transmitter 120 includes an upconverter, a parabolic antenna for transmitting data to a satellite, a communication satellite, and a ground receiving antenna.

(Receiving Unit 130) The receiving unit 130 performs various processes on the transmission information It input from the transmitter 120 to reproduce the information unit Iu, and reproduces the reproduction information Ir which is the content of the information unit Iu. Present to the user. Receiver 130
Is a receiver 131, a lower layer descrambler 132, a demultiplexer 133, an information unit descrambler 134,
It includes a regenerator 135 and a presenter 136.

The receiver 131 is connected to the transmitter 120 and receives the input of the transmission information It to receive the encrypted multiplexed information unit I.
Generate me. That is, the receiver 131 is connected to the transmitter 120
And all or a part of the transmission information It input from. The receiver 131 further outputs the extracted transmission information It.
Generates an encrypted multiplex information unit Ime based on Example 1
In, the receiver 131 is a mail transmission front-end program. On the other hand, in Example 2, the receiver 131 connects a satellite broadcast tuner, a demodulator, and an error correction complex.

The lower-layer descrambler 132 is connected to the receiver 1
In response to the input of the encrypted multiplex information unit Ime, the multiplex information unit Im is generated. The lower layer descrambler 132 decrypts the encrypted multiplex information unit Ime input from the receiver 131 to generate a multiplex information unit Im. In Example 1, the lower-layer descrambler 132
The GP program is activated with the option of decryption. On the other hand, in Example 2, the lower layer descrambler 132 is a transport layer descrambler.

The encrypted multiplexed information unit Ime generated by the lower layer descrambler 132 is substantially the same in content as the encrypted multiplexed information unit Ime generated by the lower layer scrambler 114 of the transmitting unit 110. However, a different encryption format or encryption method can be used.

The demultiplexer 133 separates the encrypted information unit Iue from the multiplexed information unit Im input from the lower layer descrambler 132, and extracts and outputs the same.
If the information decrypted from the multiplex information unit includes the information unit Iu that does not need to be decrypted, the demultiplexer 1
Reference numeral 33 separately outputs the encrypted information unit Iue and the information unit Iu. In the first example, the demultiplexer 133 is a MIME decoder, and separates and extracts text information, image information, and the like, which are each part included in a multipart message, separately. On the other hand, in Example 2, the demultiplexer 133
It is a demultiplexer of the G-2 TS.

The information unit descrambler 134 is connected to the demultiplexer 133, and receives only the encrypted information unit Iue. Then, the information unit descrambler 13
4 decrypts the input encrypted information unit Iue to generate an information unit Iu. However, if the encrypted information unit Iue is repeatedly encrypted by the information unit scrambler 112 as described above or the multiplexer 1
13 may be encrypted multiplexed information repeatedly multiplexed (structured).

The former, that is, the encrypted multiplex information unit (Im)
In the case where is repeatedly encrypted by the information unit scrambler 112, the encrypted information unit Iue still remains even after decryption by the information unit descrambler 134. The information unit descrambler 134 separately outputs such residual encrypted information unit Iue and information unit Iu from different output ports. In order to decrypt such a residual encrypted information unit Iue, the information unit descrambler 134 is connected to one of its output ports,
The remaining encrypted information unit Iue is circulated to itself. The information unit descrambler 134 continues the circulation of the residual encrypted information unit Iue until the residual encrypted information unit Iue disappears after decryption by itself.

In the latter case, that is, when the encrypted information unit Iue is repeatedly multiplexed (structured) by the multiplexer 113, the multiplexed information unit Im still remains even after demultiplexing by the demultiplexer 133. .
Since such a residual multiplexed information unit is hierarchically multiplexed and encrypted, the information unit descrambler 134
Before decryption, the outermost layer of the residual encrypted (repeatedly multiplexed) information unit Iue must be decrypted first. Therefore, such residual multiplex encryption (repeatedly multiplexed) information Iue is transferred to the demultiplexer 133.
Back to. As a result, the iterative demultiplexing operation by the demultiplexer 133 and / or the iterative decryption operation by the information unit descrambler 134 are continued until the decrypted information unit Iu remains without the multiplex information unit Im remaining after decryption. You. Then, the information unit descrambler 134 outputs only the information unit Iu.

Note that the information unit descrambler 134
An encrypted information unit Iue obtained by decrypting the encrypted information unit Iue input from the information unit descrambler 134
Alternatively, the information unit Iu is output. Encrypted information unit Iu
e is obtained by encrypting the information unit Iu several times. Therefore, in order to extract the information unit Iu, the encrypted information unit Iue must be decrypted a plurality of times.

The information unit descrambler 134 circulates the output from the information unit descrambler 134 itself,
By repeatedly decrypting, the encrypted information unit Iue obtained by encrypting a plurality of times can be decrypted. Even if the number of times that the information unit descrambler 134 can decrypt at one time is one, the encrypted information unit Iue
From the information unit Iu. The information unit descrambler 134 can perform decryption a plurality of times at the same time. In this case, the information unit Iu can be extracted at high speed.

The regenerator 135 is connected to the information unit descrambler 134 and the other input port of the demultiplexer 133, and receives the information unit Iu from each. Then, the reproducer 135 outputs the input information unit I
u is converted into reproduction information Ir which is reproducible information and output. In Example 1, the reproducer 135 is a text file viewer, image file presentation software, or the like.
On the other hand, in Example 2, the regenerator 135
MPE for playing back audio and images encoded in G-2
G-2 decoder. In this case, the output is NTSC (N
nationalTelevision System
(Standard Committee) signal and an analog audio signal.

The presentation device 136 receives the output of the reproduction information from the reproduction device 135 and presents the information unit Iu to the user. That is, the presenter 136 receives the output of the reproducer 135 and presents the information included in the reproduction information Ir to the user. In Example 1, the presenter 136 is an X-windows or Microsoft software that presents an image or a sound to the user.
A window system such as Windows. On the other hand, in Example 2, the presentation device 136 is a television receiver that receives and receives an NTSC signal and an analog audio signal.

(Operation) The general operation of the information transmission apparatus 100 will be described below with reference to FIGS. FIG. 3 shows the operation of transmitting section 110 and transmitter 120.

At step S301, the information unit generator 111 generates and outputs a plurality of information units Iu. The information unit Iu may be generated in the method in Example 1 in which the user inputs or designates a file, or in the example 2 in which the information unit Iu is selectively output from the stored information unit Iu according to a predetermined schedule.

In step S302, step S3
01 is recursively encrypted a plurality of times for the information unit Iu generated in step 01, and the result is set as an encrypted information unit Iue.

In step S303, step S3
A plurality of encrypted information units Iue generated by the encryption at 02 are multiplexed, and the result is output as multiplexed information Im. The multiplexer 113 multiplexes the information unit Iu generated in step S301 and outputs the result as multiplexed information Im. The multiplex information Im is MIME-compliant multipart data in Example 1, and Example 2
Is TS data of the MPEG-2 system.

In step S304, step S3
03, the lower layer scrambler 114 encrypts the multiplexed information Im obtained by the multiplexing in step 03.
Generate e. The multiplex information Im is RSA in Example 1.
It is encrypted by encryption or the like.
-2 TS payload is developed by Hitachi and Mu
It is encrypted by lti-2 encryption or the like.

In step S305, the sending unit 115
Converts the encrypted multiplexed information unit Ime obtained in step S304 into a format suitable for transmission by the transmitter 120, and generates transmission information It. In Example 1, information such as a To: field and a From: field added to the head of the mail body, which is the encrypted multiplexed information unit Ime, is output as transmission information It. On the other hand, in Example 2, after the MPEG-2 TS is encoded with an error correction code, the modulated TS is output.

In step S306, the transmitter 120
Thus, the transmission information It is transmitted to a physically distant point. Note that a plurality of receiving units 1 are
30 may correspond. In Example 1, the connected 1
A mail communication daemon mounted on one or a plurality of computers communicates with a computer network such as the Internet or a LAN (Local Area Network) based on the protocol SMTP so that the mail communication daemon on one computer changes the other computer. Send mail to the above mail communication daemon.

On the other hand, in Example 2, the transmission information It converted by the upconverter is transmitted to the communication satellite by the parabolic antenna, and the communication satellite transmits the transmission information It received by the transponder to the ground. Then, the transmission information It from the communication satellite is received by the receiving antenna on the ground.

FIG. 4 shows the operation of receiving section 130. In step S401, the receiver 131 sets the transmitter 120
A part or all of the encrypted multiplexed information unit Ime is extracted from the transmission information It input from. In Example 1, a process of extracting one piece of electronic mail data addressed to a specific user is performed. On the other hand, in example 2, a process is performed in which a specific packet storing information to be tuned to a predetermined frequency and stored is filtered and extracted by a PID (Packet ID).

In step S402, the lower layer descrambler 132 inputs the encrypted multiplex information unit Ime obtained in step S401, decrypts the cipher, and outputs multiplex information Im. In Example 1, the lower layer descrambler 132 starts the PGP program with the option of decryption. The RSA encryption is decrypted by the PGP program, and the decryption result is output. On the other hand, in Example 2, the multiplex information Im encrypted by the Multi-2 encryption is decrypted to obtain the multiplex information Im.

In step S403, the demultiplexer 133 separates and extracts the multiplexed information Im obtained in step S402 for each encrypted information unit Iue.

In step S2104, the demultiplexer 1933 separates and extracts the multiplexed information unit Im for each information unit Iu. In Example 1, the demultiplexer 1933 separates a multi-part message multiplexed based on MIME for each part. As a result, text information, image information, audio information, and the like, which are each part, are separated as a separate information unit Iu. On the other hand, in Example 2, the demultiplexer 1933 is
A plurality of streams multiplexed by the PEG-2 system are separated based on a PID (Packet ID, packet identifier). As a result, additional information such as an MPEG-2 video stream, an MPEG-1 audio stream, and an EPG is separated as a separate information unit Iu. However, MPEG-2 video is compliant with ITU-TH. 262
The audio of MPEG-1 is ISO / IEC 11172.
-3 standardized.

In step S404, it is determined whether or not the information after demultiplexing by the demultiplexer 133 is included in the encrypted information unit Iue.
YES, that is, in step S403, the demultiplexer 1
If it is determined that further decryption is necessary to extract the contents from the information generated by 33, the process proceeds to step S405.

In step S405, the information unit descrambler 134 decrypts the encrypted information unit Iue output from the demultiplexer 133 only once. Then, the process returns to step S403. These steps S
By repeating the processes in 403, S404, and S405, the information unit descrambler 134
All encrypted information units Iue included in the multiplex information Im can be decrypted. Then, the information unit descrambler 134
Can finally retrieve all the information units Iu transmitted from the transmission unit 110.

On the other hand, if NO in step S404, that is, if it is determined that there is no need to decode the information after demultiplexing by the demultiplexer 133, the information output from the demultiplexer 133 It means only Iu. In this case, the process proceeds to step S406.

At step S406, the regenerator 135
Receives the input of the information unit Iu from the information unit descrambler 134 and generates reproduction information Ir that is reproducible information.

In Example 1, for example, when the information unit Iu is text information, a font corresponding to each character code is selected and enumerated to generate a bitmap format, and the first reproduction information Ir1 Generate as Also,
JPEG (Joint Photographics)
In the case of an image information format such as Experts Group), the result of development into a bitmap format is output as reproduction information Ir1. However, JPEG is ISO
/ IEC10918 standardized. In the case of audio information, the audio information is converted into an analog audio signal by a function equivalent to that of a D / A converter and output as reproduction information Ir.

On the other hand, in example 2, step S210
If the information unit Iu obtained in step 4 is an MPEG-2 video stream, decoding of the MPEG-2 video is performed, and an NTSC signal is output as reproduction information Ir.
In the case of an audio stream, D is added to the analog audio signal.
/ A conversion and output.

In step S407, the presenter 136 is displayed.
Receives the input of the reproduction information Ir output from the reproducer 135, and presents the contents of the reproduction information Ir to the user according to the format of the reproduction information. In Example 1, when the reproduction information obtained in step S406 is in the form of a bitmap, the presenter 136 arranges and presents the reproduction information Ir on the display screen and visually presents it to the user. If the reproduction information obtained in step S406 is an analog audio signal, the analog audio signal is transmitted to a speaker, so that the analog audio signal is converted into sound and presented audibly to the user. On the other hand, in Example 2, the NTSC signal of the reproduction information Ir obtained in step S406 is received on a display, the analog audio information is sent to a speaker, and the reproduction information is presented to the user.

As described above, in the first embodiment,
The information unit Iu encrypted recursively a plurality of times can be handled. Therefore, it is possible to introduce a hierarchical structure into the encryption of the information unit Iu. By associating this hierarchical structure with the structure of a program, when a part of the information unit Iu is selectively purchased, encryption can be performed by performing only one type of encryption a small number of times.

Further, in the receiving unit 130, the information unit descrambler 134 repeatedly extracts the information to extract the information unit Iu. Therefore, the receiving unit can be configured without requiring a sophisticated or special descrambler that can handle a plurality of types of encryption or perform a plurality of decryption processes at a time, thereby achieving simplification and cost reduction.

(Generation of Encrypted Multiplexed Information Unit by Encoding Information Unit) Referring to FIG.
Will be described. In the figure, different suffixes are added to information units of each processing level in order to enhance visibility. For example, the dotted rectangle indicates the lower layer scrambler 114.
Represents the output Ime0a. The four circles represent information units Iu1a, Iu2a, Iu3a, and Iu4 output from the information unit generator 111, respectively.
a. These information units Iu1a, Iu2
a, Iu3a, and Iu4a represent, for example, a sightseeing guide, a sightseeing spot weather forecast, a nationwide weather forecast, and a district weather forecast in consideration of the weather forecast, respectively.

Each of solid line rectangles Iue1a and Iue1
2a and Iue4a represent encryption information generated at each encryption level inside the transmission unit 110 of the information transmission apparatus 100. That is, the rectangle Iue1a is
In step S302, the information unit scrambler 11
2 is the information unit Iu output from the information unit generator 111
1a represents a first encrypted information unit Iue generated by encrypting 1a with a first predetermined encryption C1 based on a first predetermined encryption method CS1. Thus, the first encrypted information unit Iue1a is generated.

Similarly, rectangle Iue12 is a second encrypted information unit Iue generated in the following two steps.
Is represented. First, in step S303, the multiplexer 113 outputs the first encryption unit Iue1a and the information unit Iu input from the information unit scrambler 112.
2a is multiplexed to generate a multiplexed information unit Im12a (not shown). In step S302, the information unit scrambler 112 converts the multiplexed information unit Im12a input from the multiplexer 113 into the second encryption method CS
2 and a second cipher C2 based on the second cipher. Thus, the second encrypted information unit Iue12a is generated.
Note that inside the second encrypted information unit Iue12a,
The information unit Iu1a has been encrypted twice.

In step S302, the information unit scrambler 112 converts the information unit Iu4a input from the information unit generator 111 into the rectangle Iue4a by the third predetermined encryption C3 based on the third predetermined encryption method CS3. It represents a third encrypted information unit Iue generated by encryption. Thus, the third encrypted information unit Iue4a is generated.

A rectangle Ime0a represents the encrypted multiplex information Ime generated as described below. First, in step S303, the multiplexer 113
Second encrypted information unit Iue12a, information unit Iu3
a and the third encrypted information unit Iue4a are multiplexed (structured) to generate a multiplexed information unit Im1234a (not shown). Next, in step S304, the lower layer scrambler 114 sets the multiplex information unit Im1234a
Is encrypted with a fourth predetermined encryption C4 based on a fourth predetermined encryption method CS4.

As a result, the first information unit Iu1a is triple-encrypted with the first, second and third predetermined ciphers C1, C2 and C4. The second information unit Iu2a is the second information unit Iu2a.
And a fourth predetermined cipher C2 and C4. The third information unit Iu3a is single-encrypted with a fourth predetermined encryption C4. Fourth information unit Iu4a
Is encrypted doubly with the third and fourth predetermined ciphers C3 and C4.

As described above, the information units Iu1a, Iu2a, and Iu representing the contents of different weather forecast programs, respectively.
There is a hierarchical relationship between 3a and Iu4a. That is, the encrypted multiplex information Ime0a is a set of information meaningful to the user. This set is, for example, one electronic mail or one information program. The encrypted multiplex information Ime0a is an unencrypted part (Iu3a)
And the encrypted part (Iue12a and Iue4a)
Is included recursively.

It is to be noted that the ciphers C1, C2, C3,
And C4 may be set to the same value, or each may be set to any value. Similarly, the encryption method CS1,
Each of CS2, CS3, and CS4 may be the same encryption method, or may be any encryption method.

One encrypted multiplex information unit (Ime0a)
As an example in which an unencrypted part (Iu3a) and an encrypted part (Iue12a and Iue4a) are included, the entire encrypted multiplexed information unit Ime0a is a weather forecast program and is not encrypted. Part (Iu3
a) is the free national weather, the encrypted part (Iue)
12a and Iue4a) may be paid detailed district forecasts. Also, movie trailers and encrypted main features,
Alternatively, there could be an article introducing the software and an executable form of the encrypted software.

[0147] In this case, the user enters the encrypted multiplexed information Ime.
0a can be decoded to view the national weather (Iu3a), and the encrypted information unit Iue2a can be decoded to obtain the weather forecast (I
u2a) can be viewed, the encrypted information unit Iue1a can be decrypted to view the sightseeing spot guide (Iu1a) in consideration of the weather forecast, and the encrypted information unit Iue4a can be decrypted to view the detailed district forecast.

In this manner, the encrypted information unit Iue encrypted a plurality of times with different ciphers is decrypted by a single cipher having a strength corresponding to the strength of the plurality of ciphers against unauthorized decryption. Has the same strength as when. Further, if a plurality of information units such as the encrypted information units Iue1a and Iu2a are simultaneously encrypted at one encryption level based on the definition 2, the load at the start of the decryption operation can be reduced.

(Generation of Information Unit from Encrypted Encrypted Multiplexed Information) The hierarchically encrypted information transmitted by the transmission unit 110 is converted into a simple Can be decrypted using a rambler. The encrypted multiplex information unit Ime0a is supplied to the receiving unit 130 in the form of transmission information It via the transmitter 120.

In step S401, the receiver 131 of the receiver 130 extracts the entire encrypted multiplex information Ime0a from the received transmission information It. Step S402
, The lower layer descrambler 132 decrypts the encrypted multiplex information Ime0a encrypted by the fourth predetermined encryption C4 to obtain the multiplex information Im1234a (not shown). Note that the multiplex information Im1234a includes a second encrypted information unit Iue12a, a third information unit Iu3a, and a third encrypted information unit Iue4a.
The multiplexed information Im1234a thus obtained is
May be generated so as to have a format different from that of the multiplex information Im1234a generated by the multiplexer 113 in step S303.

The demultiplexer 133 determines in step S4
In step S403, the multiplex information Im1234a generated in step 02 is demultiplexed to separate each encrypted information unit Iue and / or information unit Iu. In this way,
Second encrypted information unit Iue12a, third information unit I
u3a and the third encrypted information unit Iue4a are generated in step S403. Note that the information units Iue12a, Iu3a, and I
ue4a is the information unit scrambler 11 of the transmitting unit 110
2 can be generated in a different format than the one generated by. Further, the information units Iue12a, I
u3a and Iue4a can be generated in the same format as that generated by the information unit scrambler 112 of the transmission unit 110. In this case, the information unit Iue
12a, Iu3a, and Iue4a.

The second encrypted information unit Iue12a is transmitted to the information unit descrambler 134. Then, in step S405, the information unit descrambler 13
4 is a second encrypted information unit Iue using the second cipher.
Decryption unit 12a generates multiplexed information unit Im12a (not shown). Multiple information unit I thus generated
m12a is returned to the demultiplexer 133. Then, in step S403, the demultiplexer 133 demultiplexes the multiplexed information unit Im12a to generate a first encrypted unit Iue1a and a second information unit Iu2a.

In step S404, the first encryption unit Iue1a is sent to the information unit descrambler 134, where the first encryption unit Iue1a is decrypted using the first predetermined cipher C1 and the first information is decrypted. A unit Iu1a is generated. Similarly, the third encrypted information unit Iue1a is sent to the information unit descrambler 134, where the fourth encrypted information unit Iue1a is transmitted.
Is generated as the information unit Iu4a.

Information unit I generated in step S405
u1a, the information unit Iu2 generated in step S403
a, the information unit Iu3a generated in step S403,
And the information unit Iu4a generated in step S405
Are sent to the regenerator 135. Then, in step S406, these information units Iu1a, Iu1a
Reproduction information Ir is generated from u2a, Iu3a, and Iu4a. The information units Iu1a, Iu2a, Iu
Although the contents of 3a and Iu4a are the same as the information units generated by the information unit generator 111 in their contents, they may not be the same in the encryption format and the encryption method.

(Second Embodiment) An information transmission apparatus according to a second embodiment of the present invention will be described with reference to FIG. 5, FIG. 6, FIG. 7, and FIG. Information transmission device 500
Is a transmitting unit 510, a transmitter 120, and a receiving unit 530.
including. The transmitter 120 is the same as that used in the information transmission device 100. Note that, for the same components as those of the information transmission apparatus 100, the description is basically omitted hereafter to avoid redundancy.

The encrypted multiplexed information Ime generated by the descrambler 532 is substantially the same as the encrypted multiplexed information Ime generated by the lower layer scrambler 114 of the transmitting unit 110 in its contents. It can be configured differently in the encryption format or the encryption method. Needless to say, the lower layer scrambler 11
It is also possible to reproduce the encrypted multiplexed information Ime completely identical to the encrypted multiplexed information Ime generated in step 4.

(Transmission Unit 510) The transmission unit 510 has a configuration very similar to the information unit scrambler 112 of the transmission unit 110 shown in FIG. That is, in the transmitting unit 510, the information unit scrambler 112 of the information unit scrambler 112 is replaced with the information unit scrambler 512. The information unit scrambler 512 is different from the information unit scrambler 112 in that the information unit scrambler 512 must be able to encrypt the information unit Iu in conformity with the lower layer transmission by the transmitter 120. That is, the information unit scrambler 512 only needs to be able to perform encryption based on the specific encryption method used by the lower layer processed by the transmitter 120. Needless to say, the information unit scrambler 512 may be configured to perform encryption based on various encryption methods including the above-described encryption method suitable for lower layer transmission.

That is, as the encryption performed by the information unit scrambler 512, an encryption that can be decrypted by sharing a tamper-resistant device used for decrypting the encryption performed by the lower layer scrambler 514 is selected. May be. However, tamper-resistant devices are designed to take measures such as erasing stored contents when illegally disassembled, and preventing information related to confidentiality from leaving LSIs that are difficult to analyze without special equipment. Device. As a device having tamper resistance, for example, C
There is an IC card used for an S digital broadcast receiver.

(Receiving Unit 530) The receiving unit 530 has a configuration similar to that of the lower layer descrambler 132 of the receiving unit 130 shown in FIG. That is, in the receiving unit 530, the lower layer descrambler 132 and the information unit descrambler 134 are replaced by the descrambler 532 and the descrambler 533, respectively. The descrambler 532 decrypts the encrypted multiplex information Ime input from the receiver 131 once, and generates a multiplex information unit Im. The descrambler 532 can decrypt the encrypted multiplexed information based on various encryption methods including the encryption method adopted by the lower layer scrambler 114 of the transmission unit 110.

The descrambler 533 demultiplexes the multiplex information unit Im input from the descrambler 532 to generate an information unit Iu. However, when the multiple information unit Im generated by the descrambler 532 includes an information unit that is recursively multiplexed (structured), the encrypted information unit Iue remains after demultiplexing.

The descrambler 532 is further connected to the descrambler 533 and receives the input of the encrypted information unit Iue. Then, the descrambler 532 decrypts the input encrypted information unit Iue and outputs the multiplexed information unit Im.
Generate The multiplex information unit Im is supplied to the descrambler 533. When the encrypted information unit Iue input from the descrambler 533 is encrypted but not multiplexed, the information unit Iu is generated and supplied directly to the reproducer 135. In this manner, the descrambler 533 does not need to be able to demultiplex the recursively multiplexed (structured) multiplexed information unit Im, and only needs to be able to demultiplex the once multiplexed multiplexed information unit Im. Good.

As described above, the configuration according to the second embodiment removes the restriction of recursively encrypting a plurality of times by the information unit scrambler 112 from the configuration of the first embodiment.
In each case, the lower layer descrambler 132 for decrypting the encryption and the information unit descrambler 135 are integrated into one. This integration can be regarded as the function of the information unit descrambler 135 realized by the function of the lower layer descrambler 132.

(Operation) The general operation of the information transmission apparatus 500 will be described below with reference to FIGS.
The operation of the transmission unit 510 and the transmitter 120 shown in FIG. 7 is very similar to the operation already described with reference to FIG.
Therefore, the operation will be briefly described so as to clarify the difference between the two.

In step S601, the information unit generator 511 generates and outputs a plurality of information units Iu.

In step S602, each information unit Iu generated in step 601 is encrypted by the information unit scrambler 512, and the encryption result is output as an encrypted information unit Iue. However, the information unit scrambler 512 encrypts the information unit Iu according to the lower layer transmission performed by the transmitter 120. That is, the same type of encryption as the encryption used in the lower layer scrambler 114 is used here. The same type means that when the lower layer scrambler 114 uses the RSA encryption,
For example, it means that the information unit scrambler is also encrypted using the RSA encryption.

In the first embodiment, step S30
In step 2, the information unit Iu is recursively encrypted a plurality of times. However, in this step, there is no restriction that the information unit Iu is encrypted a plurality of times.

In step S603, the multiplexer 113 multiplexes the encrypted information unit Iue generated by encrypting in step S602, and outputs the result as multiplexed information Im.

In step S604, step 60
The lower layer scrambler 114 encrypts the multiplexed information Im obtained by multiplexing in step 3 using the same encryption used in step S602 to generate encrypted multiplexed information Ime. However, the encryption performed by the lower layer scrambler 114 uses the same encryption as the encryption performed by the information unit scrambler 512.

In step S605, the sending unit 115
Converts the encrypted multiplexed information Ime obtained in step S604 into a format suitable for transmission or transmission by the transmitter 120 to generate transmission information It.

Step S605 corresponds to step S605 in the operation flowchart of the transmitting unit and the transmitter according to the first embodiment.
The same as 305 may be used. In step S606, the transmitter 120 transmits the transmission information It to a physically distant point.

FIG. 8 shows an operation of receiving section 530 similar to the operation already described with reference to FIG.

In step S701, the receiver 131
Extracts part or all of the encrypted multiplex information Ime from the transmission information It input from the transmitter 120.

In step S702, the descrambler 532 inputs the encrypted multiplex information Ime obtained in step S701, decrypts the cipher, and outputs the multiplex information Im.

In step S703, the demultiplexer 533 separates the encrypted information unit Iue from the multiplex information Im obtained in step S702. Descrambler 5
33 decodes the multiplexed information unit Im recursively multiplexed, but demultiplexes the information unit Im multiplexed only once.

In step S704, the descrambler 532 decrypts the encrypted multiplexed information Ime from the receiver 131 and / or the encrypted information unit Iue from the descrambler 533. If the encrypted multiplexed information Ime or the encrypted information unit Iue has been encrypted once, 1
The information unit Iu can be generated by decrypting the cipher twice. This information unit Iu is supplied directly to the regenerator 135. When the encrypted multiplexed information Ime or the encrypted information unit Iue is encrypted and multiplexed, the multiplexed information unit Im
Is generated and supplied to the descrambler 533.

That is, when the information unit Iu is encrypted only once, the encrypted information unit Iue is once demultiplexed to generate the information unit Iu. However, in the first embodiment, the information unit Iu is limited to recursively encrypt a plurality of times, but in the second embodiment, this limitation is not necessary.

At step S705, the regenerator 135
Is the descrambler 532 and the demultiplexer 53
The information unit Iu output from the input unit 3 is input to generate reproduction information Ir that is reproducible information.

In step S706, the presenter 136 is displayed.
Receives the reproduction information Ir from the reproducer 135.

As described above, the information unit scrambler 51
2 is similar to the encryption performed by the lower-layer scrambler 114, so that a single descrambler 532 is used.
Thus, the encryption performed by the information unit scrambler 512 as well as the lower layer scrambler 114 can be decrypted. That is, the information unit Iu can be decrypted by preparing only one unspecified descrambler.

(Generation of Encrypted Multiplex Information Unit by Encoding Information Unit) With reference to FIG. 6 similar to FIG. 2, the encrypted multiple information unit Ime generated by the information transmission apparatus 500 will be described. The dotted rectangle represents Ime0b output from the lower-layer scrambler 114. The four circles represent information units Iu1b, Iu2b, Iu3b, output from the information unit generator 111, respectively.
And Iu4b. These information units Iu1
b, Iu2b, Iu3b, and Iu4b are, for example,
Tourist guides taking into account weather forecasts, weather forecasts for tourist spots,
The weather forecast for the whole country and the weather forecast for the district are shown.

The solid-line rectangles Iue12b and Iue4b represent encryption information generated at the respective encryption levels inside the transmission section 510. That is,
First, in step S603, the rectangle Iue12b multiplexes the information units Iu1b and Iu2b input from the information unit generator 111 to generate a multiplexed information unit Im12b (not shown).
In step S602, the information unit scrambler 51
2 encrypts the multiplexed information unit Im12b input from the multiplexer 113 with the fifth encryption C5 based on the fifth encryption method CS25 to generate the encrypted information unit Iue12b.

The rectangle Iue4b is generated by the information unit scrambler 512 encrypting the input information unit Iu4b with the sixth predetermined encryption C6 based on the sixth predetermined encryption method CS6 in step S602. It represents the sixth encrypted information unit Iue. Thus, the third encrypted information unit Iue4b is generated.

A rectangle Ime0b represents the encrypted multiplex information Ime generated as described below. First, in step S603, the multiplexer 113
The encrypted information unit Iue12b, the information unit Iu3b, and the encrypted information unit Iue4b are multiplexed (structured),
A multiplex information unit Im1234b (not shown) is generated.
Next, in step S604, the lower layer scrambler 114 encrypts the multiplex information unit Im1234b with a seventh predetermined encryption C7 based on a seventh predetermined encryption method CS7.

As a result, the information units Iu1b and Iu2b are both doubly encrypted by the fifth and seventh ciphers C5 and C7. The information unit Iu3b is the seventh cipher C
7 is single-encrypted. The information unit Iu4b is doubly encrypted with the sixth and seventh predetermined ciphers C6 and C7.

As described above, the information units Iu1b, Iu2b, Iu representing the contents of different weather forecast programs, respectively.
There is a hierarchy between 3b and Iu4b that is different from the hierarchy relationship in the first embodiment shown in FIG. In addition,
The ciphers C5, C6, and C7 may be set to the same value, or each may be set to any value, depending on the encryption strength required to protect the information unit from unauthorized decryption. Similarly, each of the encryption methods CS5, CS6, and CS7 may be the same encryption method, or may be any encryption method. Further, the encryption method and encryption used in the first embodiment may be used.

(Generation of Information Unit from Encrypted Encrypted Multiplexed Information) The hierarchically encrypted information transmitted by the transmitting unit 510 is converted into a simple desk top as described below. Can be decrypted using a rambler. The encrypted multiplexed information unit Ime0b is supplied to the receiver 530 in the form of transmission information It via the transmitter 120. Receiver 5
In step S701, the receiver 131 extracts the entire encrypted multiplex information Ime0b from the received transmission information It. In step S702, the descrambler 532 decrypts the encrypted multiplexed information Ime0b encrypted by the seventh predetermined encryption C7, and outputs the multiplexed information Im12.
34b (not shown) is obtained. The multiplex information Im123
4b is an encrypted information unit Iue12b and an information unit Iu3
b and an encrypted information unit Iue4b. Note that the multiplexed information Im123 thus obtained is
4b is the multiplexer 11 in step S603.
3 may be generated so as to have a format different from that of the multiplex information Im1234b generated by Step 3.

The demultiplexer 533 determines in step S7
02 is demultiplexed in step S703 to separate each encrypted information unit Iue and / or information unit Iu. In this way,
An encrypted information unit Iue12b, an information unit Iu3b, and an encrypted information unit Iue4b are generated in step S703. Note that the information units Iue12b, Iu3b, and Iue4b obtained in this manner can be generated in a format different from that generated by the information unit scrambler 512 of the transmission section 510.
Further, the information units Iue12b, Iu3b, and Iu
e4b can also be generated in the same format as that generated by the information unit scrambler 512 of the transmission unit 510. In this case, the information units Iue12b, Iu3b,
And reproduction of Iue4b.

[0188] The encrypted information unit Iue12b is transmitted to the descrambler 532. Then, step S704
, The descrambler 532 decrypts the encrypted information unit Iue12b using the fifth encryption to generate a multiplexed information unit Im12b (not shown). The multiplex information unit Im12b generated in this manner is used as a demultiplexer 53.
Returned to 3. Then, in step S703, the demultiplexer 533 demultiplexes the multiplex information unit Im12b to generate an encryption unit Iu1b and an information unit Iu2b.

At step S704, the encryption unit I
u1b is sent to the descrambler 532, where the m predetermined encryption unit C5 is used to decrypt the m encryption unit Iu1b to generate the first information unit Iu1b. Similarly, the encrypted information unit Iu1b is sent to the descrambler 532, where the information unit Iu4b is generated.

Information unit I generated in step S705
u1b, the information unit Iu2 generated in step S703
b, the information unit Iu3b generated in step S703,
And the information unit Iu4b generated in step S705
Are sent to the regenerator 135. Then, in step S705, these information units Iu1b, Iu1b
Reproduction information Ir is generated from u2b, Iu3b, and Iu4b. The information units Iu1b, Iu2b, Iu
3b and Iu4b are the same in content as the information unit generated by the information unit generator 111,
The encryption format and the encryption method need not be the same. Further, the information units Iu1b, Iu2b, Iu3b,
And Iu4b may be completely identical to the one generated by the information unit generator 111.

Referring to FIG. 9, a modification of information transmitting apparatus 500 shown in FIG. 5 will be described. The information transmission device 500R has a configuration in which the lower layer scrambler 114 is removed from the information transmission device 500. In this device, encryption for lower layer transmission is performed not by the lower layer scrambler 114 (FIG. 5) but by the information unit scrambler 512 (FIG. 9).
Done by Therefore, the information unit scrambler 5
12 only needs to be able to perform encryption based on a specific encryption method that can be used in a lower layer as implemented in the transmitter 120. Needless to say, the information unit scrambler 512
Various types of encryption may be performed, including the above-described encryption method suitable for lower layer transmission.

(Third Embodiment) FIGS. 10, 11, and 1
An information transmission apparatus according to a third embodiment of the present invention will be described with reference to FIG. The information transmission device 800 according to the present embodiment includes a transmission unit 810, a transmitter 120, and a reception unit 830. Hereinafter, the information transmission devices 100, 500,
Or, descriptions of elements substantially the same as those of the 500R will be omitted to avoid redundancy.

[0193] The encrypted multiplexed information Ime generated by the descrambler 832 is substantially the same as the encrypted multiplexed information Ime generated by the lower layer scrambler 114 of the transmitting unit 810, although the content is the same. It can be configured differently in its encryption format or encryption method. It is a matter of course that the encrypted multiplexed information Ime completely identical to the encrypted multiplexed information Ime generated by the lower layer scrambler 114 can be generated.

(Transmission Unit 810) The transmission unit 810 has substantially the same configuration as the configuration of the transmission unit 510 already described with reference to FIG. However, the operation of the transmitting unit 810 that generates the encrypted multiplex information Ime is the same as that of the transmitting unit 510.
The difference from the operation according to the first embodiment will be described later with reference to FIGS.

(Receiving Unit 830) The receiving unit 830 has a configuration similar to that of the receiving unit 530 shown in FIG. That is, in the configuration of the demultiplexer 533, the descrambler 532 and the demultiplexer 533 are replaced with the descrambler 832 and the demultiplexer 833. The descrambler 832 once decrypts the encrypted multiplex information Ime input from the receiver 131 to generate a multiplex information unit Im. In addition, the descrambler 832 can decrypt the information unit encrypted hierarchically and recursively. The descrambler 832 decrypts the information unit encrypted n times (n is an integer) and the information unit encrypted n-1 times. Therefore, based on the number of encryptions of the encrypted multiplex information Ime input from the receiver 131,
The descrambler 832 is repeatedly decrypted until the encrypted information unit Iue is exhausted.

The demultiplexer 833 demultiplexes the multiplexed information unit Im input from the descrambler 832 to generate an information unit Iu. However, when the multiplexed information unit Im generated by the descrambler 832 includes the encrypted information unit Iue, the encrypted information unit Iue is circulated to the descrambler 832.

(Operation) The general operation of the receiving section 830 of the information transmission apparatus 800 will be described with reference to FIG. As described above, the transmission unit 810 substantially corresponds to the transmission unit 5
Since it has the same configuration as 10, it is the same as that already described with reference to FIG. The general operation of receiving section 830 is as follows.

In step S901, the receiver 131
Receives the transmission information It from the transmitter 120 and extracts a part or all of the encrypted multiplex information Ime from the input.

In step S902, the descrambler 832 inputs the encrypted multiplex information Ime obtained in step S901, decrypts the code, and outputs the multiplex information Im.

[0200] In step S903, the demultiplexer 833 outputs the multiplexed information I obtained in step S902.
m, and the encrypted information unit Iue and / or the information unit Iu are extracted.

In step S904, it is determined whether the information unit Iu output from the descrambler 832 or the demultiplexer 833 has been encrypted. If YES, that is, if the information unit Iu is encrypted, the information unit Iu (Iue) output from the descrambler 832 or the demultiplexer 833 is returned to the descrambler 832. Then, the process proceeds to step S905. However, if the determination is NO, that is, if the information unit Iu output from the descrambler 832 or the demultiplexer 833 is not encrypted at all, the information unit Iu output from the descrambler 832 or the demultiplexer 833 is output to the reproducer 135. Is transmitted to Then, the process proceeds to step S906.

At step S906, the regenerator 135
Receives the output from the descrambler 832 and / or the demultiplexer 833 to generate reproduction information Ir.

In step S907, the presenter 136 is displayed.
Presents the reproduction information Ir obtained in step S906 to the user according to the format of the reproduction information Ir.

As described above, the information unit scrambler 51
2 recursively encrypts the lower layer scrambler 1
By using the same encryption method as the information unit scrambler 512 in 14, it becomes possible for the descrambler 832 to decrypt the encryption for all of these encryptions.

(Generation of Encrypted Multiplex Information Unit by Encoding Information Unit) With reference to FIG. 11, which is very similar to FIG. 2, the encrypted multiple information unit Ime generated by the information transmission apparatus 800 will be described. The dotted rectangle represents Ime0c output from the lower layer scrambler 114. The four circles represent information unit generators 11 respectively.
1, the information units Iu1c, Iu2c, Iu
3c and Iu4c. These information units Iu1c, Iu2c, Iu3c, and Iu4c represent, for example, a sightseeing spot guide in consideration of the weather forecast, a sightseeing spot weather forecast, a nationwide weather forecast, and a district weather forecast, respectively.

Each of solid rectangles Iue1c and Iue1
2c and Iue4c represent encryption information generated at each encryption level inside the transmission unit 810. That is, the rectangle Iue1c is obtained by the information unit scrambler 512 converting the information unit Iu1c input from the information unit generator 111 into the eighth predetermined encryption method CS8.
Is generated using the predetermined encryption CS8.

The rectangle Iue12c has an encrypted information unit Iu
e and consists of the following two steps.
First, the multiplexer 113 multiplexes the encrypted information unit Iue1c and the information unit Iu2c input from the information unit scrambler 512 to form a multiplexed information unit Im12c.
(Not shown). Second, the information unit scrambler 512 encrypts the multiplexed information unit Im12c with the ninth predetermined encryption C9 of the ninth predetermined encryption method CS9. In this way, an encrypted information unit Iue12c in which the information unit Iu1 is encrypted twice is generated.

The rectangle Iue4c is obtained by encrypting the information unit Iu4c input from the information unit generator 111 by the information unit scrambler 512 with the tenth encryption based on the tenth predetermined encryption method CS10. Is generated.

[0209] The rectangle Ime0c contains the encrypted multiplex information Ime.
Which is generated as follows. First, the multiplexer 113 multiplexes the encrypted information unit Iue12c, the information unit Iu3c, and the Iue4c to generate a multiplexed information unit Im1234c (not shown). Next, the lower layer scrambler 114 converts the multiplex information unit Im1234 into the first
Eleventh predetermined encryption C1 based on the first encryption method C11
In step 1, the multiplex information unit Im1234 is encrypted.

As a result, the data is triple-encrypted with the eighth, ninth, and eleventh predetermined ciphers C8, C9, and C11. The information unit Iu2c is doubly encrypted with ninth and eleventh predetermined ciphers C9 and C11. The information unit Iu3c is single-encrypted with an eleventh predetermined encryption C11. The information unit Iu4c is doubly encrypted with tenth and eleventh predetermined ciphers C10 and C11.

Note that, depending on the encryption strength required to protect the information unit from unauthorized decryption, the encryption C8, C9, C1
0 and C11 may be set to the same value, or each may be set to an arbitrary value. Similarly, encryption method C
Each of S8, CS9, CS10, and CS11 may be the same encryption method, or may be any encryption method. Further, the encryption method and encryption used in the first embodiment and the second embodiment may be used.

(Generation of Information Unit from Encrypted Encrypted Multiplexed Information) The hierarchically encrypted information transmitted by the transmission unit 810 is converted into a simple desk top as described below. Can be decrypted using a rambler. The encrypted multiplexed information unit Ime0c is supplied to the receiver 830 in the form of transmission information It via the transmitter 120.

[0213] In step S901, the receiver 131 of the receiving section 830 extracts the entire encrypted multiplexed information Ime0c from the received transmission information It. Step S902
, The descrambler 832 decrypts the encrypted multiplexed information Ime0c encrypted with the eleventh predetermined encryption C11 to obtain the multiplexed information Im1234c (not shown).
The multiplex information Im1234c has an encrypted information unit Iu
e12c, information unit Iu3c, and encrypted information unit I
ue4c. The multiplex information Im1234c obtained in this manner is output to the multiplexer 11
3 may be generated so as to have a format different from that of the multiplex information Im1234c generated by Step 3.

The demultiplexer 133 determines in step S9
In step S903, the multiplex information Im1234c generated in step 02 is demultiplexed to separate each encrypted information unit Iue and / or information unit Iu. In this way,
An encrypted information unit Iue12c, an information unit Iu3c, and an encrypted information unit Iue4c are generated in step S903. The information units Iue12c, Iu3c, and Iue4c obtained in this manner can be generated in a format different from that generated by the information unit scrambler 512 of the transmission unit 810.
Further, the information units Iue12c, Iu3c, and Iu
The e4c can be generated in the same format as that generated by the information unit scrambler 512 of the transmission unit 810. In this case, the information units Iue12c, Iu3c,
And reproduction of Iue4c.

Steps S904 and S905
, The reproduction information Ir becomes information units Iu1c, Iu2c,
Reproduction information Ir is generated from Iu3c and Iu4c. The information units Iu1c, Iu2c, Iu3c, and Iu4c are the same in content as the information unit generated by the information unit generator 111, but need not be the same in the encryption format and encryption method. Also, the information units Iu1c, Iu2c, Iu3c, and I
u4c may be completely identical to the one generated by the information unit generator 111.

Referring to FIG. 13, a modified example of information transmitting apparatus 800 shown in FIG. 10 will be described. The information transmission device 800R includes:
It has a configuration in which the lower layer scrambler 114 is removed from the information transmission device 800. In this apparatus, encryption for lower layer transmission is performed by a lower layer scrambler 114 (FIG. 1).
Information unit scrambler 512, not by 0)
(FIG. 13). Therefore, the information unit scrambler 512 only needs to be able to perform encryption based on a specific encryption method that can be used in the lower layer as implemented in the transmitter 120. Needless to say, the information unit scrambler 5
12 may be capable of performing various encryptions, including the encryption methods suitable for lower layer transmissions described above.

(Fourth Embodiment) FIGS. 14, 15, and 1
An information transmission apparatus according to a fourth embodiment of the present invention will be described with reference to FIG. 6 and FIG. The information transmission device 1000 includes a transmission unit 1010, a transmitter 120, and a reception unit 1030. Hereinafter, descriptions of elements substantially the same as those of the information transmission apparatuses 100, 500, 500R, 800, or 800R will be omitted to avoid redundancy.

(Transmission Unit 1010) The transmission unit 1010 has a configuration very similar to that of the transmission unit 110 according to the first embodiment shown in FIG. This is a configuration in which the unit scrambler 512 is replaced. The information unit scrambler 512 recursively encrypts the information unit Iu input from the information unit generator 111 a plurality of times, and generates an encrypted information unit Iu.
Generate e. The information unit scrambler 512 adds an encrypted information unit identifier which is an identifier for distinguishing the information unit Iu from the output encrypted information unit. Hereinafter, the encrypted information unit identifier is referred to as an encrypted information unit ID for simplification.

Here, the encrypted information unit Iue is, so to speak, composed of a child's encrypted information unit Iue, but rather than adding an encrypted information unit ID to the encrypted information unit Iue, it is the most parent. It is assumed that an encrypted information unit ID is added to the encrypted information unit. As the encrypted information unit ID, the same value is assigned to the information unit Iu updated with time. For example, the same encrypted information unit ID is assigned to the nationwide weather information unit Iu yesterday and today's nationwide weather information unit.

(Receiving Unit 1030) The receiving unit 1030 includes a receiver 131, a lower layer descrambler 132, a demultiplexer 1033, a storage device 1034, an information unit descrambler 1035, and a reproducer 1036. Receiver 1
030 is the receiving unit 1 according to the first embodiment shown in FIG.
It has a configuration similar to 30. That is, the receiving unit 13
0 and demultiplexer 133 and regenerator 135
However, in the receiving unit 1030, the demultiplexer 103
3 and a regenerator 1036. Further, the storage device 1034 stores the demultiplexer 10
33 and a regenerator 1036 are newly inserted. The storage 1034 includes demultiplexers 1033 and 1036.
And the encrypted information unit Iue and the reproduction instruction information I
Receives the input of dr. The storage unit 1034 is further connected to the information unit descrambler 1035 and exchanges the encrypted information unit Iue with each other.

The storage unit 1034 stores the input encrypted information unit Iue, and updates the stored encrypted information unit Iue to the latest one by replacing the stored encrypted information unit Iue when the encrypted information unit Iue is updated. When the stored encryption information unit Iue is specified by the input reproduction specification information Idr, the encryption information unit Iu is stored.
e is output. The information unit descrambler 1035 receives the encrypted information unit Iue output from the storage device 1034 and the encrypted information unit Iue output from the information unit descrambler 1035 itself, and outputs the encrypted information unit Iue (encryption). The information unit Iu that is not encrypted is also an encrypted information unit Iue by definition.)

[0222] The reproducer 1036 receives the information unit Iu output from the information unit descrambler 1035, and outputs reproduction information Ir and reproduction designation information Idr. The reproducer 1036 may be the same as the reproducer 135 in the first embodiment except that the reproduction designation information Idr is output. However, the reproduction specifying information Idr is information for specifying the information unit Iu, and specifies the information unit Iu included in the encrypted information unit Iue stored in the storage device 1034. The information unit Iu specified by the reproduction specification information Idr may be determined by direct input by the user, or may be determined independently by the information transmission apparatus 1000 itself. Presenter 136
Inputs the reproduction information Ir output from the reproducer 1036,
The content included in the reproduction information Ir is presented to the user. The presenter 136 may be the same as the presenter 136 in the first embodiment. (Operation) The operation of the information transmission apparatus 1000 will be described with reference to FIGS. 15, 16, and 17. FIG. 15 is a flowchart illustrating the operation of the transmitting unit 1010 and the transmitter 120. In step S1101, the information unit generator 111 generates and outputs a plurality of information units Iu.

In step S1102, the information unit Iu generated in step S1101 is recursively encrypted by the information unit scrambler 512, and the result is set as an encrypted information unit Iue.

In step S1103, step S
An encrypted information unit ID is added to the encrypted information unit generated in 1102. Since the information unit Iu is added to the result of encryption in step S1102, the encrypted information unit ID can be easily extracted without decrypting the encrypted information unit Iue.

In step S1104, the multiplexer 113 multiplexes the encrypted information unit Iue generated by encrypting in step S1103, and outputs the result to the multiplexed information Iue.
Output as m.

In step S1105, step S
The lower layer scrambler 114 encrypts the multiplexed information Im obtained by multiplexing in 1104, and encrypts the multiplexed information Im.
Generate e. The encryption performed in this step uses the same encryption as the encryption performed in step S1102.

At step S1106, the sending unit 11
5 converts the encrypted multiplexed information Ime obtained in step S1105 into a format suitable for transmission by the transmitter 120, and generates transmission information It.

At step S1107, the transmitter 12
0 transmits transmission information to a physically distant point.
At this time, a plurality of receiving units may correspond to one transmitting unit.

FIG. 16 is a flowchart showing the operation of receiving section 1030 of information transmission apparatus 1000. In step S1201, the receiver 131 inputs the transmission information from the transmitter 120, and receives the encrypted multiplexed information Ime from the input.
Take out part or all of. In step S1202, the lower-layer descrambler 132 executes step S1
The encrypted multiplexed information Ime obtained in 201 is input, the code is decrypted, and the multiplexed information Im is output.

In step S1203, the demultiplexer 1033 separates and extracts the multiplexed information Im obtained in step S1202 for each encrypted information unit Iue. In step S1204, the storage device 1034 stores the encrypted information unit Iue using the encrypted information unit ID.

FIG. 17 is a flowchart showing details of the operation of storage device 1034 in step S1204. In step S1301, the demultiplexer 1
From 033, the encrypted information unit Iue is input.

In step S1302, step S1302
In step 1301, the value i of the encrypted information unit ID added to the input encrypted information unit Iue is obtained.

In step S1303, a search is made to determine whether the encrypted information unit Iue whose encrypted information unit ID is i is already stored in the storage 1034.

At step S1304, step S
If it is determined in step S1303 that the data has already been stored, the process advances to step S1306.

In step S1305, step S
The encrypted information unit Iue input in 1301 is added and saved. Thereafter, the process returns to step S1301 to repeat the processing.

In step S1306, the encryption information unit Iu whose encryption information unit ID is currently stored is i.
e, and saves the encrypted information unit Iue input in step S1301 instead. Then, step S
Returning to step 1301, the process is repeated.

As described above, since the information unit Iu stored in the storage device 1034 is encrypted as the encrypted information unit Iue, confidentiality is ensured even if the contents of the storage device 1034 are illegally referred to. You.

At the time of updating, since the encryption information unit ID is assigned to the encryption information unit Iue which is the most parent, the encryption information unit Iue output from the demultiplexer 1033 is replaced with the encryption information unit ID. It is easy to take out. Since only the easily extracted encrypted information unit ID is used, the process of updating the contents of the storage device 1034 can be realized very easily.

If information indicating whether or not the encrypted information unit ID has been updated is added to the encrypted information unit ID, the processing of the storage unit 1034 for the encrypted information unit Iue that has been sent many times without being changed can be performed. It can be simplified. Examples of the information indicating whether the information has been updated include (1) a flag indicating that the information has been updated, (2) a numerical value indicating the version, and (3) a checksum of the entire information.

[0240] In step S1205, the regenerator 10
36 outputs the reproduction designation information Idr Step S1
The process proceeds to 206, and if not output, returns to step S1201.

In step S1206, the storage device 10
34 retrieves the encrypted information unit Iue having the encrypted information unit ID specified by the reproduction designation information Idr output in step S1205 from the storage device 1034 and outputs it.

In step S1207, the encrypted information unit Iue input by the information unit descrambler 1035
If the information unit Iu to be extracted exists in an unencrypted state, the process proceeds to step S1209.

In step S1208, the information unit descrambler 1035 decrypts the encrypted information unit Iue in which the information unit Iu desired to be extracted exists by 1
Execute it twice. Then, the process returns to step S1207.

At step S1209, the reproduction device 10
Reference numeral 36 denotes reproduction information I, which is information that can be reproduced by inputting the information unit Iu output from the information unit descrambler 1035.
Generate r.

In step S1210, the presenter 13
6 represents the reproduction information Ir obtained in step S1209,
It is presented to the user according to the format of the reproduction information Ir.

As described above, by adding the encryption information unit ID to the encryption information unit Iue and adding the storage unit 1034, the information unit descrambler 1035 does not perform the decryption processing of the encryption, so that the storage unit 1034 Can be updated to the latest one. Also, when the user actually watches the content, the information unit descrambler 1035 decrypts the code.

It should be noted that the information unit descrambler 134 used in the above-described embodiment must be able to simultaneously decrypt the encrypted multiplexed information Iu (Ime). On the other hand, the information unit descrambler 1035 stores the decryption result of the encrypted information for one stage in the storage 1034.
Once, the above time constraint is not required. For example, by receiving information little by little from the storage device 1034, the decryption process may be performed at a low processing speed regardless of the transmission speed of the information transmitted by the transmitter 120.

If the processing is not completed within a predetermined period, the encrypted information unit Iue can be temporarily output to the storage device 1034. The temporarily stored information is then output to the information unit descrambler 1035 for processing.

As described above, the encrypted information unit Iue is
Information unit descrambler 1 from storage 1034 little by little
035. The supplied encrypted information unit Iue is gradually divided into the information unit descrambler 103.
5 is output. As a result, the demultiplexer 10
33 can demultiplex the multiplexed information at a lower speed than the transmission speed of the transmitter 120.

The reproducer 1036 instructs the contents of the information to be supplied to the storage 1034 according to the request of the user. For this purpose, the reproducer 1036 outputs the reproduction instruction information Id
Generate r. With this reproduction instruction information Idr, decoding at any desired timing is possible. Thus, even if the encryption key is supplied later than the encryption information (It), the receiving unit 1030 can process the encryption information.

(Fifth Embodiment) FIGS. 18, 19, and 2
The information transmission apparatus according to the fifth embodiment of the present invention will be described with reference to FIG. The configuration of the information transmission apparatus 1400 in this example is different from the information transmission apparatus 1000 according to the fourth embodiment shown in FIG. 14 in that the restriction of recursively encrypting a plurality of times by the information unit scrambler 1035 is removed. The descrambler 1032 and the information unit descrambler 1035 are integrated into one descrambler 1432. In this integration, the function of the information unit descrambler 1035 is
It can be considered that the function is realized by the second function.

The information transmission apparatus 1400
, A transmitter 1420, and a receiving unit 1430. The transmitting unit 1410 includes an information unit generator 111,
Information unit scrambler 1012 and multiplexer 11
3, a lower-layer scrambler 114, and a transmitter 115. The information unit generator 111 generates and outputs encrypted multiplexed information Ime.

The information unit scrambler 1012 receives the information unit Iu output from the information unit generator 111, encrypts the information unit Iu, and outputs an encrypted information unit Iue. Further, the information unit scrambler 1012 adds an encrypted information unit ID, which is an identifier for distinguishing the information unit Iu, from the output encrypted information unit Iue. The method of adding the encrypted information unit ID may be the same as that of the information unit scrambler 1012 in the fourth embodiment. Multiplexer 11
3 inputs the encrypted information unit Iue output from the information unit scrambler 1012 and the information unit Iu output from the information unit generator 111, and outputs multiplexed information Im.

The lower layer scrambler 114 receives the multiplex information Im output from the multiplexer 113, encrypts the multiplex information Im, and outputs the encrypted multiplex information Ime. Transmitter 115
Inputs the encrypted multiplexed information Ime output from the lower layer scrambler 114 and outputs transmission information. Transmitter 120
Transmits the input transmission information to a physically distant point. The transmitter 120 is the transmitter 1 in the first embodiment.
It may be the same as 20.

The receiving section 1430 includes a receiver 131, a descrambler 1432, a demultiplexer 1433,
It comprises a storage device 1034, a reproduction device 1036, and a presentation device 166. The receiver 131 receives the transmission information output from the transmitter 120 and outputs encrypted multiplex information Ime. The descrambler 1432 inputs the encrypted multiplexed information Ime output from the receiver 1431 and the encrypted information unit Iue output from the storage 1434. When receiving the encrypted multiplex information Ime, the descrambler 1432 outputs the multiplex information Im.

When the encrypted information unit Iue is input, the encryption is decrypted and the resulting encrypted information unit Iue is decrypted.
Is output. The descrambler 1432 may be the same as the descrambler 532 in the second embodiment. The demultiplexer 1433 receives the multiplexed information Im output from the descrambler 1432 and inputs the multiplexed information Im into the encrypted information unit Iue.
Is output.

The storage device 1034 is provided with the demultiplexer 14
33, the encrypted information unit Iue output from the
6 and outputs the reproduction designation information Idr, and outputs an encrypted information unit Iue. The storage device 1034 stores the input encrypted information unit Iue, and stores the encrypted information unit Iue.
Information unit Iue stored when is updated
Update to the latest one by replacing. When the stored encrypted information unit Iue is specified by the input reproduction specifying information Idr, the encrypted information unit Iue is output. The reproducer 1036 receives the information unit Iu output from the descrambler 1432, and outputs reproduction information Ir and reproduction designation information Idr.

The presenter 136 receives the reproduction information Ir output from the reproducer 1036 and presents the user with the contents included in the reproduction information Ir. The presenter 1436 may be the same as the presenter 136 in the first embodiment.

FIG. 19 is a block diagram of the transmitting section 1 of the information transmitting apparatus 1400.
14 is a flowchart showing the operation of the transmitter 410 and the transmitter 1420.

In step S1501, the information unit generator 111 generates and outputs a plurality of information units Iu.

In step S1502, each information unit Iu generated in step S1501 is encrypted by the information unit scrambler 141, and the result is set as an encrypted information unit Iue.

In step S1503, step S
An encrypted information unit ID is added to the encrypted information unit Iue generated in 1502.

Step S1503 may be the same as step S1103 in the operation flowchart of the transmitter and the transmitter according to the fourth embodiment.

In step S1504, the multiplexer 113 multiplexes the encrypted information unit Iue generated by encryption in step S1502, and outputs the result to the multiplexed information Im.
Output as

In step S1505, step S
The lower layer scrambler 114 encrypts the multiplexed information Im obtained by multiplexing in 1504 and obtains the encrypted multiplexed information Im.
Generate e. However, the encryption performed by the lower layer scrambler 114 uses the same encryption as the encryption performed by the information unit scrambler 1012. Step S15
In 06, the transmitter 115 transmits the encrypted multiplexed information Ime obtained by encrypting in step S1505 to the transmitter 120.
The information is converted into a format suitable for transmission in the, and transmission information is generated.

Step S1506 may be the same as step S305 in the operation flowchart of the transmitter and the transmitter according to the first embodiment.

At step S1507, the transmitter 12
0 transmits transmission information to a physically distant point.
At this time, a plurality of receiving units may correspond to one transmitting unit.

FIG. 20 shows the receiving unit 1 of the information transmitting apparatus 1400.
430 is a flowchart showing the operation of 430.

At step S1601, the receiver 13
1 inputs the transmission information from the transmitter 120 and extracts a part or all of the encrypted multiplex information Ime from the input.

In step S1602, the descrambler 1432 inputs the encrypted multiplex information Ime obtained in step S1601, decrypts the encryption, and
Output m.

In step S1603, the demultiplexer 1433 separates and extracts the multiplexed information Im obtained in step S1602 for each encrypted information unit Iue.

At step S1604, the storage device 10
34, using the encrypted information unit ID, the encrypted information unit I
Save ue.

[0273] In step S1605, the playback device 10
36 outputs the reproduction designation information Idr Step S1
The process proceeds to 606, and if not output, returns to step S1601.

In step S1606, the storage device 10
34 has the encrypted information unit ID specified by the reproduction specification information Idr output in step S1605.
The encrypted information unit Iue is extracted from the stored one and output.

In step S1607, the descrambler 1432 decrypts the encrypted information unit Iue to generate the information unit Iu. If the information unit Iu is encrypted once, the information unit Iu can be obtained by decrypting the information once.
u can be generated. However, in the fourth embodiment, the information unit Iu is limited to recursively encrypt a plurality of times, but the second embodiment does not have this limitation.

In step S1608, the playback device 10
36 is the information unit I output by the descrambler 1432
u is input to generate reproduction information Ir that is reproducible information. Step S1608 may be the same as step S406 in the operation flowchart of the receiving unit of the first embodiment.

In step S1609, the presentation unit 13
6 represents the reproduction information Ir obtained in step S1608,
It is presented to the user according to the format of the reproduction information Ir.

As described above, the information unit scrambler 10
12 is similar to the encryption performed by the lower-layer scrambler 114, so that a single descrambler 14
At 32, the encryption performed by the information unit scrambler 1012 as well as the lower layer scrambler 114 can be decrypted. That is, only one non-special descrambler
Only by preparing one, the information unit Iu can be decrypted. Further, by adding the encryption information unit ID to the encryption information unit Iue and adding the storage device 1034, the descrambler 1432 does not perform the decryption processing of the encryption.
It is possible to update the encrypted information unit Iue stored in the storage device 1034 to the latest one. In addition, when the user actually views the content, the descrambler 1432 decrypts the code.

(Sixth Embodiment) With reference to FIGS. 22, 23 and 24, an information transmission apparatus according to a sixth embodiment of the present invention will be described. The information transmission apparatus 1700 according to the present embodiment is recursively encrypted a plurality of times by inputting the output of the descrambler 1432 according to the fifth embodiment shown in FIG. 18 again to the descrambler 1432 itself. The information unit Iu can be handled.

FIG. 22 shows a schematic configuration of the information transmission apparatus 1700. The information transmission device 1700 includes a transmission unit 1710
, A transmitter 120, and a receiving unit 1730. The transmitting unit 1710 includes an information unit generator 111, an information unit scrambler 1012, and a multiplexer 113.
, A lower layer scrambler 114, and a transmitter 115.

The information unit generator 111 generates and outputs encrypted multiplexed information Ime. Information unit scrambler 10
12 is an information unit Iu output from the information unit generator 111
, And recursively encrypt a plurality of times to output an encrypted information unit Iue. Information unit scrambler 1
Numeral 012 adds an encrypted information unit ID which is an identifier for distinguishing the information unit Iu from the output encrypted information unit Iue.

The multiplexer 113 receives the encrypted information unit Iue output from the information unit scrambler 1012 and outputs multiplexed information Im. Lower layer scrambler 11
4 inputs the multiplexed information Im output from the multiplexer 113, encrypts the multiplexed information Im, and outputs the encrypted multiplexed information Ime. The transmitter 115 inputs the encrypted multiplexed information Ime output from the lower layer scrambler 114 and outputs transmission information.

The transmitter 120 receives the transmission information output from the transmitter 115 and transmits the transmission information to a physically distant point. The receiving unit 1730 includes a receiver 131, a descrambler 1732, a demultiplexer 1433, a storage device 1034, a reproducer 1036, and a presenter 136.

The receiver 131 receives the transmission information output from the transmitter 120 and outputs encrypted multiplex information Ime.
The descrambler 1732 inputs the encrypted multiplexed information Ime output from the receiver 131 and the encrypted information unit Iue output from the storage device 1034. Descrambler 173
2 outputs the multiplex information Im when the encrypted multiplex information Ime is input. When the encrypted information unit Iue is input, the encryption is decrypted and the resulting encrypted information unit Iue is decrypted.
ue is output.

The demultiplexer 1433 receives the multiplexed information Im output from the descrambler 1732 and outputs an encrypted information unit Iue. The storage unit 1034 stores the encrypted information unit Iue output from the demultiplexer 1433.
And the reproduction designation information Idr output from the reproducer 1036, and outputs an encrypted information unit Iue. Memory 10
Numeral 34 stores the input encrypted information unit Iue, and updates the stored encrypted information unit Iue to the latest one by replacing the stored encrypted information unit Iue when the encrypted information unit Iue is updated.

When the stored encrypted information unit Iue is specified by the input reproduction specifying information Idr, the encrypted information unit Iue is output. The reproducer 1036 receives the information unit Iu output from the descrambler 1732, and outputs the reproduction information Ir and the reproduction designation information I
and dr. Regenerator 1036 and presenter 136
Inputs the reproduction information Ir output from the reproducer 1036,
The content included in the reproduction information Ir is presented to the user. The presenter 136 may be the same as the presenter 136 in the first embodiment.

(Operation) Referring to FIG.
The operation of 0 will be described in detail.

At step S1801, the receiver 13
1 inputs the transmission information from the transmitter 120 and extracts a part or all of the encrypted multiplex information Ime from the input.
In step S1802, the descrambler 1732
Is the encrypted multiplex information Im obtained in step S1801.
e, decrypt the code, and output the multiplex information Im.

In step S1803, the demultiplexer 1433 separates and extracts the multiplexed information Im obtained in step S1802 for each encrypted information unit Iue.

At step S1804, the storage device 10
34, using the encrypted information unit ID, the encrypted information unit I
Save ue.

[0291] In step S1805, the regenerator 10
36 outputs the reproduction designation information Idr Step S1
The process advances to step 806, and if not output, returns to step S1801.

At step S1806, the storage device 10
34 has an encryption information unit ID specified by the reproduction specification information Idr output in step S1805.
The encrypted information unit Iue is extracted from the stored one and output.

If it is determined in step S1807 that the information unit Iu to be taken out exists in the encrypted information unit Iue input by the descrambler 1732 in an unencrypted state, the flow advances to step S1809.

[0294] In step S1808, the descrambler 1732 decrypts the encrypted information unit Iue once for the encrypted information unit Iue in which the information unit Iu to be extracted exists. Then, the process returns to step S1807.

[0295] In step S1809, the regenerator 10
36 is the information unit I output by the descrambler 1732
u is input to generate reproduction information Ir that is reproducible information.

In step S1810, the presenter 13
6 represents the reproduction information Ir obtained in step S1809,
It is presented to the user according to the format of the reproduction information Ir.

As described above, the information unit scrambler 10
By using the same encryption scheme as the information unit scrambler 112 in the lower layer scrambler 114, the descrambler 1732 can decrypt all of these encryptions. become.

Also, by adding an encryption information unit ID to the encryption information unit Iue and adding a storage device 1034,
The encrypted information unit Iue stored in the storage device 1034 can be updated to the latest one without performing the decryption processing of the encryption by the descrambler 1732. In addition, when the user actually watches, the descrambler 1732 decrypts the code.

FIG. 24 shows the information transmission apparatus 1 shown in FIG.
7 shows a modification of the embodiment 700. The information transmission device 1700R according to the present modification also has the information transmission device 1
700 to the lower layer scrambler 114 from the information transmission device 1
Since the structure is removed from 700, detailed description is omitted.

As described above in detail, according to the present invention, the same encryption is recursively applied to the information unit Iu a plurality of times, and the decryption is performed a plurality of times by one descrambler. The information transmission apparatus can be simplified by not only performing encryption with a greater degree of freedom compared to the above, but also suppressing the addition of a special descrambler or descrambler.

Further, an encrypted information unit ID added after the encryption of the information unit Iu is introduced, and the contents of the newly provided storage are updated based on this ID. Then, at the time of actual viewing, the code is decrypted by a descrambler and viewed. As a result, not only can the update management of the contents of the storage device be easily realized, but also the descrambling at the time of previewing the stored data can prevent unauthorized viewing by a user who does not pay a fee, and decrypt the encryption. It has a high affinity with the system that charges a fee when doing so.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an information transmission device according to a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of an encrypted multiplex information unit generated by the information transmission device shown in FIG.

FIG. 3 is a flowchart showing operations of a transmission unit and a transmitter of the information transmission device shown in FIG.

FIG. 4 is a flowchart showing an operation of a receiving unit of the information transmission device shown in FIG.

FIG. 5 is a block diagram illustrating an information transmission device according to a second embodiment of the present invention.

6 is an explanatory diagram of an encrypted multiplex information unit generated by the information transmission device shown in FIG.

FIG. 7 is a flowchart showing an operation of a transmission unit and a transmitter of the information transmission device shown in FIG.

FIG. 8 is a flowchart showing an operation of a receiving unit of the information transmission device shown in FIG.

FIG. 9 is a block diagram showing a modification of the information transmission apparatus shown in FIG.

FIG. 10 is a block diagram illustrating an information transmission device according to a third embodiment of the present invention.

11 is an explanatory diagram of an encrypted multiplex information unit generated by the information transmission device shown in FIG.

FIG. 12 is a flowchart showing the operation of a transmission unit and a transmitter of the information transmission device shown in FIG.

FIG. 13 is a block diagram showing a modification of the information transmission apparatus shown in FIG.

FIG. 14 is a block diagram illustrating an information transmission device according to a fourth embodiment of the present invention.

FIG. 15 is a flowchart showing an operation of a transmission unit and a transmitter of the information transmission device shown in FIG.

FIG. 16 is a flowchart showing an operation of a receiving unit of the information transmission device shown in FIG.

FIG. 17 is a flowchart showing an operation of a storage device of the information transmission device shown in FIG.

FIG. 18 is a block diagram illustrating an information transmission device according to a fifth embodiment of the present invention.

19 is a flowchart showing the operation of the transmission unit and the transmitter of the information transmission device shown in FIG.

FIG. 20 is a flowchart showing an operation of a receiving unit of the information transmission device shown in FIG.

21 is a block diagram showing a modification of the information transmission device shown in FIG.

FIG. 22 is a block diagram illustrating an information transmission device according to a sixth embodiment of the present invention.

FIG. 23 is a flowchart showing the operation of the receiving unit of the information transmission device shown in FIG.

24 is a block diagram showing a modification of the information transmission device shown in FIG.

FIG. 25 is a block diagram showing a conventional information transmission device.

26 is an explanatory diagram of an encrypted multiplexed information unit generated by the information transmission device shown in FIG. 25.

FIG. 27 is a flowchart showing the operation of the transmission unit and the transmitter of the information transmission device shown in FIG.

FIG. 28 is a flowchart showing the operation of the receiving unit of the information transmission device shown in FIG.

[Description of Signs] 100, 500, 500R, 800, 800R, 100
0, 1400, 1700, 1700R Information transmission device 110, 510, 510R, 810, 810R, 101
0, 1410, 1710, 1710R Transmitter 111 Information unit generator 112, 512, 1012 Information unit scrambler 113 Multiplexer 114 Lower layer scrambler 115 Transmitter 120 Transmitter 130, 530, 1430 Receiver 131 Receiver 132 Lower layer desk Rambler 133, 532, 832, 1430, 1732 Descrambler 134 Information unit Descrambler 135, 1036 Reproducer 136 Presenter 533, 833, 1033, 1433 Demultiplexer 1034 Storage

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Isao Masuda 1006 Kazuma Kadoma, Kadoma City, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (38)

[Claims] An information transmission apparatus used in an information transmission system for communicating between at least two parties encrypted information composed of a plurality of information units that are hierarchically encrypted and multiplexed, wherein the information is transmitted. An information unit generating means for generating the information unit and a first encryption means for encrypting the information unit by a first encryption method to generate an encrypted information unit; An information transmission apparatus comprising: a first multiplexing unit that multiplexes at least one of the information unit and the encrypted information unit to generate a multiplexed information unit. A second encryption unit that encrypts the multiplexed information by a second encryption method to generate the encrypted multiplexed information; and a second encryption unit that multiplexes the encrypted information unit to generate the multiplexed information. 2. The information transmission apparatus according to claim 1, further comprising two multiplexing units. 3. The information transmission apparatus according to claim 2, further comprising: third encryption means for encrypting the multiplexed information by a third encryption method to generate encrypted multiplexed information. 4. The information transmission apparatus according to claim 3, wherein the third encryption method is the same as that used for the encrypted information. 5. The information transmission apparatus according to claim 3, wherein the second encryption method is the same as the third encryption method. 6. The information transmission apparatus according to claim 3, wherein said first, second, and third encryption methods are the same. 7. The information transmission apparatus according to claim 1, further comprising a transmission unit configured to convert the encrypted multiplexed information into a format suitable for efficient transmission. 8. The information transmission apparatus according to claim 1, wherein said first encryption means encrypts said information unit by an encryption method suitable for information transmission. 9. An information transmission apparatus used in an information transmission system for communicating between at least two parties encrypted information composed of a plurality of information units hierarchically encrypted and multiplexed with each other, wherein the encrypted information is A first decryption unit that decrypts the first multiple information unit by a first decryption method to generate a first multiple information unit, and a first encrypted information unit and a second encrypted information unit that demultiplexes the first multiple information unit. First demultiplexing means for generating any of a multiplexed information unit and the information unit; and decrypting the first encrypted information unit by a second decryption method to obtain the information unit or the second encryption An information transmission device including a second decryption unit that generates an information unit. 10. A second demultiplexing means for demultiplexing the second multiplexed information, and a second demultiplexing means for deciphering the second encrypted information unit by a third deciphering method to generate the information unit. The information transmission apparatus according to claim 9, further comprising: third decoding means. 11. The information transmission apparatus according to claim 9, wherein the first decryption method is the same as that used for the encrypted information. 12. The apparatus according to claim 1, further comprising storage means provided between said first demultiplexing means and said second decryption means for storing said first and second encrypted information units.
An information transmission device according to claim 1. 13. The encrypted information unit is input from the second decryption means to generate reproduction information indicating the content of the encrypted information, and the encrypted information stored in the storage means is transmitted to the second decryption means. 13. The information transmission apparatus according to claim 12, further comprising a reproducing unit that requests the second decoding unit to supply the information. 14. An information transmission method used in an information transmission system for communicating between at least two parties encrypted information comprising a plurality of information units that are hierarchically encrypted and multiplexed, wherein the information is transmitted. An information unit generating step of generating the information unit, and an encryption step of encrypting the information unit by a first encryption method to generate an encrypted information unit; and An information transmission method comprising a multiplexing step of multiplexing at least one of a unit and the encrypted information unit to generate a multiplexed information unit. 15. An encryption step of encrypting the multiplexed information by a second encryption method to generate the encrypted multiplexed information, and a multiplexing step of multiplexing the encrypted information unit to generate the multiplexed information unit. The information transmission method according to claim 14, further comprising: 16. The information transmission method according to claim 15, further comprising an encryption step of encrypting the multiplexed information by a third encryption method to generate encrypted multiplexed information. 17. The information transmission method according to claim 16, wherein the third encryption method is the same as that used for the encrypted information. 18. The information transmission method according to claim 16, wherein the second encryption method is the same as the third encryption method. 19. The information transmission method according to claim 16, wherein the first, second, and third encryption methods are the same. 20. The information transmission method according to claim 14, further comprising a conversion step of converting the encrypted multiplexed information into a format suitable for efficient transmission. 21. The information transmission method according to claim 14, wherein in the encryption step, the information unit is encrypted by an encryption method suitable for information transmission. 22. An information transmission method used in an information transmission system for communicating between at least two parties encrypted information composed of a plurality of information units hierarchically encrypted and multiplexed, wherein the information is transmitted. A first decryption step of decrypting the encrypted information by a first decryption method to generate a first multiple information unit, and demultiplexing the first multiple information unit Demultiplexing to generate one of a first encrypted information unit, a second multiplexed information unit, and the information unit, and decrypts the first encrypted information unit by a second decryption method A second decryption step of generating the information unit or the second encrypted information unit. 23. A second demultiplexing step of demultiplexing the second multiplexed information, and a step of deciphering the second encrypted information unit by a third deciphering method to generate the information unit. 23. The information transmission apparatus according to claim 22, further comprising a third decoding step. 24. The information transmission method according to claim 22, wherein the first decryption step is the same as that applied to the encrypted information. 25. The information transmission method according to claim 14, further comprising a storage step of storing the first and second encrypted information units. 26. Receiving the encrypted information unit from the second decryption means to generate reproduction information indicating the content of the encrypted information, and to generate the encrypted information stored in the storage means by the second decryption means. 26. The information transmission method according to claim 25, further comprising a reproducing step of requesting the second decoding means to supply the information. 27. An information transmission system for communicating between at least two parties encrypted information comprising a plurality of information units hierarchically encrypted and multiplexed, wherein the information is encrypted for transmission. And an information unit generating means for generating the information unit; a first encrypting means for encrypting the information unit by a first encryption method to generate an encrypted information unit; A first multiplexing unit that multiplexes at least one of the encrypted information units to generate a multiplexed information unit; and a second multiplexing unit that decrypts the encrypted information by a first decryption method to generate a first multiplexed information unit. 1 deciphering means, and first demultiplexing for demultiplexing the first multiplexed information unit to generate one of a first encrypted information unit, a second multiplexed information unit, and the information unit Means; and the first encrypted information unit An information transmission apparatus comprising: a second decryption unit that decrypts data by a second decryption method to generate the information unit or the second encrypted information unit. 28. A second encrypting means for encrypting the multiplexed information by a second encryption method to generate the encrypted multiplexed information, and a second encrypting means for multiplexing the encrypted information unit to generate the multiplexed information. The information transmission system according to claim 27, further comprising two multiplexing means. 29. The information transmission system according to claim 28, further comprising third encryption means for encrypting the multiplexed information by a third encryption method to generate encrypted multiplexed information. 30. The information transmission system according to claim 29, wherein the third encryption method is the same as that used for the encrypted information. 31. The information transmission system according to claim 29, wherein the second encryption method is the same as the third encryption method. 32. The information transmission system according to claim 29, wherein the first, second, and third encryption methods are the same. 33. The information transmission system according to claim 27, further comprising a transmission unit that converts the encrypted multiplexed information into a format suitable for efficient transmission. 34. The information transmission system according to claim 27, wherein said first encryption means encrypts said information unit by an encryption method suitable for information transmission. 35. A second demultiplexing means for demultiplexing the second multiplexed information, and a second demultiplexing means for deciphering the second encrypted information unit by a third deciphering method to generate the information unit. 28. The information transmission system according to claim 27, further comprising: third decoding means. 36. The information transmission system according to claim 27, wherein the first decryption method is the same as that used for the encrypted information. 37. The apparatus according to claim 2, further comprising storage means provided between said first demultiplexing means and said second decryption means for storing said first and second encrypted information units.
8. The information transmission system according to 7. 38. Receiving the encrypted information unit from the second decryption means to generate reproduction information indicating the content of the encrypted information, and generating the reproduction information indicating the contents of the encrypted information, 31. The information transmission system according to claim 30, further comprising a reproducing unit that requests the second decoding unit to supply the information.