WO2001091365A1

WO2001091365A1 - Data distribution system

Info

Publication number: WO2001091365A1
Application number: PCT/JP2001/004240
Authority: WO
Inventors: Toshiaki Hioki; Yoshihiro Hori; Takahisa Hatakeyama; Masataka Takahashi; Tadaaki Tonegawa; Takeaki Anazawa
Original assignee: Sanyo Electric Co., Ltd.; Fujitsu Limited; Pfu Limited; Hitachi, Ltd.; Nippon Columbia Co., Ltd.
Priority date: 2000-05-22
Filing date: 2001-05-21
Publication date: 2001-11-29
Also published as: AU2001258793A1; TW510112B

Abstract

Through the internet (40), download servers (31. 1 to 30. n) transmit content data encrypted by LCM encoders (31.1 to 31.n) according to encryption methods corresponding to the download servers (30.1 to 30.n). In response to a content distribution request of a mobile telephone (100), a distribution server (30) receives the data through the Internet (40), decodes the received data by LCM decoders (11.1 to 11.n), encrypts the content data requested by the mobile telephone (100) by a predetermined encryption method, and distributes it by radio.

Description

Data distribution system technical field

The present invention relates to a configuration of an information distribution system for distributing information to terminals such as a mobile phone and a personal computer. Background art

Advances in the Internet and information communication networks have made it possible for each user to easily access network information using personal computers and personal terminals using mobile phones.

In such information communication, information is transmitted by digital signals. Therefore, for example, each user can transmit music and video information without deteriorating sound quality or image quality in the information communication network as described above.

Therefore, it would be beneficial for copyright owners to be able to distribute copyrighted material information via the rapidly expanding information and communication network and to collect appropriate fees.

However, when copyrighted creations such as music data and image data are transmitted over such information and communication networks, the existence of copyrights must be addressed unless appropriate measures are taken to protect copyrights. There is a risk that the duplication of data will flood the information and communications network, significantly infringing the rights of the copyright holder.

Looking at distribution via the Internet, content data distribution services that have copyrights such as music are starting to be launched, while distribution of content data via mobile telephone networks is also becoming practical. Is about to be.

Therefore, the system of the download server that distributes to the personal personal computer via the Internet and the system of the distribution server that distributes the content data via the mobile phone network cannot exchange the content data with each other. If the system is configured to be an independent system, from the system side, Double investment is required and efficiency is poor. Also, from the user's point of view, a problem may occur when the delivery of the desired content cannot be received from only one of the systems. Disclosure of the invention

It is an object of the present invention to protect a user's contents such as music data through an information communication network such as the Internet or an information communication network such as a portable telephone network while protecting copyright. An object of the present invention is to provide a data distribution system capable of supplying data.

In order to achieve the above object, a data distribution system according to the present invention includes a data information communication network and a distribution relay server.

The data information communication network transmits, from a plurality of content data suppliers, content data encrypted by a corresponding plurality of first predetermined encryption schemes. The distribution relay server receives the content data requested by the first user terminal from the data information communication network in response to the content distribution request from the first user terminal, and encrypts the content data by the second predetermined encryption method. And distribute it.

The distribution relay server includes a plurality of first content data decryption units, a content data encryption unit, and a transmission unit. The plurality of first content data decryption units decrypt the content data encrypted by the plurality of first predetermined encryption methods from the plurality of content data suppliers. The content data encryption unit receives the output of the first content data decryption unit, encrypts the content data with a second predetermined encryption method, and generates encrypted content data. The transmitting unit distributes the encrypted content data.

Therefore, in the data distribution system according to the present invention, the user is allowed to protect the copyright through the information communication network such as the Internet or the information communication network such as the mobile phone network while protecting the user's hand music data or the like. It is possible to supply content data. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a schematic diagram for schematically explaining the overall configuration of the data distribution system of the present invention. It is a reminder.

FIG. 2 is a conceptual diagram showing a case where content data is distributed to the personal computer 60 in the data distribution system.

FIG. 3 is a diagram illustrating characteristics of a key related to encryption used for communication and data to be distributed in the data distribution system shown in FIG.

FIG. 4 is a schematic block diagram showing the configuration of the relay server 10 shown in FIG. FIG. 5 is a schematic block diagram for explaining the configuration of mobile phone 100 shown in FIG.

FIG. 6 is a schematic block diagram for explaining the configuration of memory card 110 shown in FIG.

FIG. 7 is a first flowchart for explaining a distribution operation that occurs when content is purchased in the data distribution system according to the first embodiment.

FIG. 8 is a second flowchart for explaining the distribution operation that occurs when the content is purchased in the data distribution system according to the first embodiment.

FIG. 9 is a third flowchart for explaining a distribution operation that occurs when the content is purchased in the data distribution system according to the first embodiment.

FIG. 10 is a flowchart for explaining the operation of each unit during the reproduction session.

FIG. 11 is a first flowchart illustrating a distribution operation that occurs when a content is purchased in a modification of the first embodiment.

FIG. 12 is a second flowchart for explaining the distribution operation that occurs when the content is purchased in the modification of the first embodiment.

FIG. 13 is a third flowchart for explaining a distribution operation that occurs when a content is purchased in the modification of the first embodiment. BEST MODE FOR CARRYING OUT THE INVENTION

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

[Example 1]

In the following, the configuration of a data distribution system that distributes music data to each user via a mobile phone network and the Internet network will be described as an example. As will be apparent from the following description, the present invention The present invention is not limited to such a case, and can be applied to a case where other copyrighted data such as image data and game software, etc. are distributed via another information communication network. Things.

Referring to FIG. 1, download servers 30.1 to 30.n for managing copyrighted music data and distributing it via the Internet 40 perform encryption processing for protecting the content data, respectively. Licensed Compliant Module (hereinafter abbreviated as LCM) Encoder 31.1 to 3.1n. The download servers 30.1 to 30.n use the LCM encoders 31.1 to 31.n to convert the content data read from the corresponding content databases 32.1 to 32.n according to a predetermined encryption method. After being encrypted, it is output to the Internet network 40. The LCM encoder 3 1.1 to 31.n uses an encryption method for content protection in the download server 30.1 to 31.n, each of which uses its own predetermined encryption method. The processing in the LCM encoders 31.1 to 31.n is not necessarily the same processing. Even if the same encryption method is adopted, the keys used for encryption and decryption are not necessarily the same.

Therefore, the distribution relay server (hereinafter, simply referred to as “relay server”) 10

It has LCM decoders 11.1 to 11.n for decoding data encrypted by the CM encoders 31.1 to 31.n and transmitted by the Internet network 40, respectively. The license distribution control unit 12 in the relay server 10 receives the data from the LCM decoders 11.1 to 11.n, encrypts the data for distribution on the mobile phone network, and distributes the information. To the mobile phone company, which is the delivery carrier 20 for.

The distribution carrier 20 relays a distribution request (delivery request) from each user to the relay server 10 through its own mobile phone network.

When there is a distribution request, the relay server 10 confirms that the user's memory card is Confirm that the device is a device, and receive encrypted data corresponding to the requested music data from the download server 30.1 to 30.0.n and decode it with the LCM decoder 11.1 to 1.1.n. The content data is distributed to each user's mobile phone via the mobile phone network of the delivery carrier 20 after being encrypted.

In FIG. 1, for example, a removable memory card 110 is attached to a user's mobile phone 100. The memory card 110 receives the encrypted content data received by the mobile phone 100, and confirms that the music playback unit (not shown) in the mobile phone 100 is an authorized device. The encryption performed for the transmission is decrypted and provided to the music reproducing unit.

Further, for example, the user 1 can "play" such content data and listen to music through a headphone 130 or the like connected to the mobile phone 100.

In the following, the distribution server 30 will be collectively referred to as the relay server 10 and the distribution carrier end (mobile phone company) 20.

The process of transmitting content data from the distribution server 30 to each mobile phone or the like is referred to as “distribution”.

By adopting such a configuration, first, a user who has not purchased a legitimate mobile phone and a legitimate memory card is difficult to receive distribution data from the distribution server 30 and reproduce it. Becomes

In addition, the distribution carrier 20 counts the frequency of distribution of content data for, for example, one song, thereby distributing a copyright fee generated each time a user receives content data distribution. If the call end 20 is to be collected as a mobile phone call fee, it becomes easier for the copyright holder to secure the copyright fee. At this time, for example, the user 2 having the memory card 112 can receive the distribution of the content data directly from the distribution server 30 by using his / her mobile phone 102. However, if the user 2 directly receives content data or the like having a considerable amount of information from the distribution server 30, a relatively long time may be required for the reception. In such a case, the content data can be copied from the user 1 who has already received the content data. If this is made possible, the convenience for the user will be improved.

However, from the viewpoint of protecting the rights of copyright holders, it is not allowed in the system configuration to freely copy free content data.

As shown in FIG. 1, for the data received by user 1, the license information necessary to copy the content data itself and enable the content data owned by user 1 to be played (right to play) When the license information is moved to user 2, the license information is referred to as “migration”. In this case, the encrypted content data and license information are transferred between the memory cards 110 and 112 via the mobile phones 100 and 102. That is, when the license information is output from the source memory card 110 to the destination memory card 112, the license information is deleted from the memory card 110, and the user 1 receives the content data. Cannot be played. Here, the “license information” includes, as described later, a content decryption key capable of decrypting content data encrypted according to a predetermined encryption method, and a license ID or information relating to copyright protection. And copyright information such as restriction information on access reproduction.

For "move", the license information can be copied only for the license information permitted by the copyright holder. This case is called “copying” of the license information. The license information is not deleted from the memory card 110 after the license information is output from the memory card 110 of the copy source to the memory card 1 12 of the copy destination. That is, both user 1 and user 2 can reproduce the content data.

Furthermore, it is also possible to copy only the content data without “moving” or “copying” the license information.In this case, since no license information is involved, the user 2 must reproduce the content data. Can not. Although not described here, the new distribution that distributes only the license information including the content decryption key allows the user 2 to reproduce the content data. With such a configuration, the receiver can flexibly use the content data once distributed by the distribution server 30.

Also, the mobile phones 100 and 102 are PHSs (Personal Handy Phones). In such a case, a call in a so-called transceiver mode is possible, and it is possible to transfer information between user 1 and user 2 using such a function.

FIG. 2 is a conceptual diagram showing a case where content data is distributed to a personal computer 60 via an Internet provider 50 in the data distribution system shown in FIG.

It is assumed that the user of the personal computer 60 has a contract with the download server 30.i among the download servers 30.1 to 30.n.

The personal computer 60 is equipped with an LCM decoder 62 corresponding to the download server 30.i as hardware or software.

In the personal computer 60, after the content data distributed from the provider 50 is decrypted by the LCM decoder 62, and further encrypted again by the local LCM encoder 64, it is stored in the recording device 66. Is stored. When a user listens to music, the encrypted content data stored in the recording device 66 is read out from the recording device 66, and the encryption performed by the local LCM encoder 66 is performed by the oral L. The music is decoded by the CM decoder 67, and the music is played back by the music playback unit 68 after being decrypted.

With this configuration, the download servers 30.1 to 30.n can distribute to the personal computer 60 of the contracted user via the Internet 40 and the provider 50. At the same time, it becomes possible to distribute to the users of the mobile phone 100 and the memory card 110 that can receive the distribution via the relay server 10 via the mobile telephone network via the carrier 20. . The personal computer 70 in FIG. 2 will be described later.

[System key and data configuration]

FIG. 3 is a diagram illustrating characteristics of a key related to encryption used for communication and data to be distributed in distribution from distribution server 30 shown in FIG. 1 to user's mobile phone 100. .

First, Data distributed from the distribution server 30 is content data such as music data. As described later, the content data Data is at least An encryption component that has been encrypted with a decryption key Kc.

The data is distributed to the user from the distribution server 30 in the format {Data} Kc.

In the following, the notation {Y} X indicates that the data データ is information obtained by converting data に into a cipher that can be decrypted with the key X.

Further, the distribution server 30 distributes, along with the content data, additional data Data-inf as plain text data such as a work related to the content data or server access. That is, the additional data Data-inf includes information for specifying the content data such as the music title of the content data, and information for specifying whether the server is a distribution server 30 or the like.

Next, the following are keys related to encryption / decryption / reproduction processing of content data and authentication of the validity of a mobile phone as a content reproduction circuit and a memory card as a recording device. That is, as described above, a content decryption key Kc for decrypting the content data supplied after being encrypted, a public encryption key KPp (x) of the content reproduction circuit (cellular phone 100), and a memory card Public encryption key KPmc (X) is provided.

The data encrypted by the public encryption key KPp (χ) and KPmc (x) is the secret decryption key Kp (x) unique to the content reproduction circuit (cell phone 100) and the secret specific to the memory card. Each can be decrypted with the decryption key Kmc ( _X ). The public encryption keys KPp (x) and KPmc (X) are asymmetric encryption keys that can be decrypted by the secret decryption keys Kp (χ) and Kmc (x), respectively. These unique secret decryption keys have different contents for each type of mobile phone and each type of memory card. Here, the types of mobile phones and memory cards are defined based on the types of manufacturers that manufacture them and the differences in the manufacturing time (production lot), and the natural number X is used for each memory card and content reproduction circuit (mobile phone). Indicates the number for distinguishing the type of telephone.

In addition, there is a public authentication key KPma that is used in common throughout the distribution system. Note that the public encryption keys KPmc (X) and KPp (x) set for each memory card and content playback unit described above are (KPmc (XPc (x)) as certified data that can be authenticated using the above authentication key KPma. x)} KPma and {KPp (x)} KPma in the form of a memory card at the time of shipment And the mobile phone respectively. In the following, data with a certificate including a public encryption key is referred to as recognition data.

Furthermore, when a user purchases a content decryption key or the like as information for controlling the operation of the devices constituting the system, that is, the mobile phone 100 and the memory card 110 as the content reproduction circuit, The purchase condition information AC transmitted from the telephone set 100 to the distribution server 30 to specify the purchase condition and the purchase condition information AC are transmitted from the distribution server 30 to the memory card 110 according to the purchase condition information AC. Access control information AC1 indicating a limit on the number of times of access to the memory card 110, etc .;

There is reproduction circuit control information AC2 indicating the restriction on the reproduction condition of the raw circuit. The reproduction condition of the reproduction circuit means, for example, conditions such as allowing reproduction of only a predetermined time at the beginning of each content data, for example, when distributing a sample at a low price or free of charge as a promotion of a new song.

In addition, as a key for managing data processing in the memory card 110, a public encryption key KPm (i) (i: natural number) set for each recording device called a memory card, and a public encryption key KPm There is a unique secret decryption key Km (i) for each memory card capable of decrypting the data encrypted in (i). Here, the natural number i represents a number for distinguishing each memory card.

In addition, there are the following as keys used for data communication. That is, as a key for maintaining confidentiality in data transfer between the memory card and the outside of the memory card, the server 30, mobile phone 100, or 102, 'A common key Ks 1 to Ks generated in the memory card 110 or 112 is used.

Here, the common keys Ksl to Ks4 are unique common keys generated for each “session” which is a unit of communication or access between the distribution server, the mobile phone, or the memory card. The common keys Ksl to Ks4 of are referred to as “session keys”.

These session keys Ksl to Ks4 are managed by the distribution server, the mobile phone, and the memory card by having a unique key for each communication session. You.

Specifically, the session key Ksl is generated for each distribution session by the license server in the distribution server. The session key Ks2 is generated for each distribution session and movement (reception side) session by the memory card, and the session key Ks3 is similarly generated for each reproduction session and movement (transmission side) session on the memory card. The session key Ks4 is generated for each playback session on the mobile phone. In each session, these session keys are given and received, a session key generated by another device is received, encryption is performed using this session key, and a content decryption key is transmitted. Security strength can be improved.

Furthermore, the data exchanged between the distribution server and the mobile phone includes a content ID for the system to identify the content data, and a management to identify when and to whom the license was issued. There are a license ID, which is a code, and a transaction ID, which is generated for each distribution session and identifies each distribution session. The transaction ID may be used as the license ID.

[Configuration of Relay Server 10]

FIG. 4 is a schematic block diagram showing the configuration of the relay server 10 shown in FIG. The relay server 10 communicates with the communication device 301 for transmitting and receiving data to and from the Internet network 40, and from the LCM encoders 31.1 of the download servers 30.1 to 30.n via the communication device 3◦1. 31. Send and receive data to and from the download server 30.1 to 30. LCM encoders provided to protect the music data (content data) downloaded from 30.n LCM encoder 31. 1 to 31. LCM decoder for receiving and decrypting music data (encrypted content data) encrypted in 31.1 n respectively. 1-1. 1.n, a key for encrypting the content data (content decryption key) Kc generating section 306 that generates Kc, and the content data from LCM decoder 1 1.1. Key (content decryption key) Kc Encryption processing unit 308 for encryption, additional information, A license database 302 for storing data such as the license ID and the license ID, and a charging database 304 for storing charging data in accordance with the distribution of music data license information for each user. And a data processing unit 310 for receiving data from the license database 302 and the charging database 304 via the data bus BS0 and performing predetermined processing, and a distribution carrier 2 via a communication network. A communication device 350 for exchanging data between the data processing unit 310 and the data processing unit 310 is provided.

The data processing unit 310 is controlled by a distribution control unit 315 for controlling the operation of the data processing unit 310 according to the data on the data bus BS0, and is controlled by the distribution control unit 315. The session key generation unit 316 for generating the session key Ks1 during the distribution session, and the authentication data {KPmc (y)} KPma sent from the memory card via the mobile phone to the communication device 350 and The decryption unit 312 receives the data via the data bus BS1 and decrypts the authentication key KPma, and the session key Ksl generated by the session key generation unit 316 is obtained by the decryption unit 312. Encrypted using the public encryption key KPmc (y) and output to the data bus BS 1, and encrypted by the session key Ks 1 for each user. The transmitted data is transmitted over data bus BS 1. And a decryption processing unit 320 that performs decryption processing upon reception.

The data processing unit 310 further encrypts the license information output from the distribution control unit 315 with the public encryption key KPm (x) unique to the memory card obtained by the decryption processing unit 320. And an encryption unit for further encrypting the output of the encryption processing unit 326 and the output of the encryption processing unit 326 with the session key Ks2 given from the decryption processing unit 320 and outputting the encrypted data to the data bus BS1. And a chemical processing unit 328.

[Configuration of mobile phone 100]

FIG. 5 is a schematic block diagram for explaining the configuration of mobile phone 100 shown in FIG.

In the mobile phone 100, the natural number X representing the type (class) is x = l.

The mobile phone 100 is used to receive a signal wirelessly transmitted by the mobile phone network. Transmitter / receiver 1 for receiving signals from antennas 1102 and 1121 and converting them to baseband signals, or modulating data from mobile phone 100 and giving them to antennas 1102 104, a data bus BS2 for exchanging data of each part of the mobile phone 100, and a controller 11 for controlling the operation of the mobile phone 100 via the data bus BS2. 0 and 6.

The mobile phone 100 further provides a touch key section 1108 for giving an external instruction to the mobile phone 100, and information output from the controller 1106 and the like to the user as visual information. And a sound reproducing unit 111 for reproducing sound based on data received via the data bus BS 2 in a normal call operation. A connector for transmitting and receiving data between the input and output terminals and a converter for converting data from the connector to a signal that can be supplied to the data bus, or converting data from the data bus to the data bus. And an external interface unit 112 for converting the signal into a signal which can be given to the connector 111.

The mobile phone 100 further includes a removable memory card 110 for storing encrypted music data (encrypted content data) and for storing information for decryption processing at any time, and a memory card 110. A memory interface for controlling the transfer of data between 0 and the data bus BS 2 and a public encryption key KPp (l) set for each class of mobile phone are authenticated with an authentication key KPma An authentication data holding unit 1500 that holds authentication data encrypted in a possible state.

The mobile phone 100 further decrypts the data received from the data bus BS2 with the Κρ holding unit 1502 that holds the secret decryption key Kp (l) unique to the mobile phone (content reproduction circuit). A decryption processing unit 1504 that decrypts with the key ρ (1) and obtains the session key Ks3 generated by the memory card, and a reproduction that reproduces the content data stored in the memory card 110 In a session, a session key generator 1508 for generating a session key Ks4 for encrypting data exchanged on the data path BS2 between the memory card 110 and the memory card 110 by a random number or the like. The encryption key processing unit 1506 that encrypts the session key Ks 4 obtained by the session key Ks 3 obtained by the decryption processing unit 1504 and outputs it to the data bus BS 2, Set data Decryption with the key Ks 4 And a decryption processing unit 1510 for outputting the content decryption key Kc and the reproduction circuit control information AC2.

The mobile phone 100 further receives the decrypted content data {DatalKc from the data bus BS2, decrypts it with the content decryption key Kc acquired from the decryption processing unit 1510, and outputs the content data. Unit 15 16, a music playback unit 15 18 for receiving the output of the decryption processing unit 15 16 to play back the content data, a music playback unit 15 18 and a voice playback unit 1 1 1 2 And a connection to receive the output of the mixing unit and selectively output according to the operation mode, and a connection to receive the output of the mixing unit and connect to the headphone Including terminal 153.

Here, the reproduction circuit control information AC2 output from the decryption processing section 15010 is supplied to the controller 1106 via the data bus BS2.

In FIG. 5, for simplicity of explanation, only blocks related to the distribution and reproduction of music data of the present invention among blocks constituting the mobile phone are shown, and blocks relating to the call function originally provided in the mobile phone are shown. Is partially omitted.

[Configuration of Memory Card 110]

FIG. 6 is a schematic block diagram for explaining a configuration of memory card 110 shown in FIG.

As described above, the public encryption key KPm (i) and the corresponding secret decryption key Km (i) are unique values for each memory card, but in the memory card 110, this natural number i = l. In addition, KPmc ( _X ) and Kmc (x) are provided as a public encryption key and a secret decryption key specific to the type (class) of the memory card. In the memory card 110, the natural number X is x == l.

The memory card 110 sends signals to and from the memory interface 1200.

Data bus BS 3 transmitted / received via 202, authentication data holding unit 140K holding {KPmc (l)} KPma as authentication data, and unique decryption key set for each type of memory card A Kmc holding unit 1402 holding Ktnc (l), and a KPm (l) holding unit 1 4 16 holding a public encryption key KPra (l) uniquely set for each memory card, A Km (1) holding unit 1442 1 for holding a secret decryption key Kra (l) capable of decrypting data encrypted by the public decryption key KPra (l).

Here, the authentication data holding unit 1400 encrypts and holds the public encryption key KPmc (l) set for each memory card class in a state in which it can be decrypted with the authentication key KPma. The memory card 110 also has a memory interface 1 on the data bus BS3.

From the data provided from 200, the distribution server 30 generates a secret decryption key Krac (l) unique to each memory card type from the Kmc (1) storage unit 1402 in the distribution session Decryption processing unit 144 that outputs the session key Ks 1 generated by the other memory card or the session key Ks 3 generated in the moving session to the contact point Pa, and an authentication key holding unit 1 that holds the authentication key KPma. In response to 4 14 and the output of the authentication key holding unit 14 14, the data provided to the data bus BS 3 is subjected to decryption processing using the authentication key KPma, and the decryption result is transmitted to the controller 1 via the data bus BS 4. 4 2 0, a decryption processing unit 1408 which outputs to the encryption processing unit 1 410, and a key selectively provided by the switching switch 1442, selectively provided by the switching switch 144 4. Data on the data bus BS 3 And a cryptographic processing unit 1 4 0 6.

The memory card 110 also outputs the session key generators 144 and 18 that generate the session key Ks2 or Ks3 in each of the distribution, playback, and movement sessions. An encryption processing unit 1410 that encrypts the session key Ks3 with the public encryption key KPp (x) or KPmc (x) obtained by the decryption processing unit 1408 and outputs it to the data bus BS3; The data encrypted by the session key Ks2 or Ks3 is received from the data bus BS3, and is decrypted by the session key Ks2 or Ks3 obtained from the session key generating section 1418. And a signal processing unit 1 4 1 2 to be sent to 4. The memory card 110 further includes an encryption processing unit 1 4 2 4 for encrypting data on the data bus BS 4 with another public encryption key KPra (i) (i ≠ 1) unique to the memory card. And a decryption processing unit 1 4 2 2 for decrypting the data on the data bus BS 4 with the secret key Km (l) unique to the public key KPm (l). And the license information including the content decryption key Kc decrypted by the decryption processing unit 142. License holder 144 for receiving information (content decryption key _Kc , content ID, license ID, access control information AC1, reproduction circuit control information AC2) from data bus BS4, and storing the encrypted content. And a memory for receiving and storing data {Data} Kc and additional data Data-inf from the data bus BS3. The license holding unit 1440 and the memory 1415 are not particularly limited, but are configured by, for example, a semiconductor memory such as a flash memory.

The memory card 110 further exchanges data with the outside via the data bus BS 3, receives reproduction information with the data bus BS 4, and operates the memory card 110. And a controller for control.

The license holding unit 1440 can exchange license information with the data bus BS4. The license holding unit 1440 has N (N: natural number) banks, and holds a part of the reproduction information corresponding to each license for each bank.

In FIG. 6, the area enclosed by the dotted line indicates that if unauthorized external opening processing is performed on the memory card 110, internal data will be erased or the internal circuit will be destroyed. It is assumed that the module is incorporated in the modules TRM1 and TRM2 for disabling the reading of data in the circuit existing in the area. Such a module is commonly referred to as a Tamper Resistance Module.

Of course, the configuration including the memories 14 and 15 may be incorporated in the module TRM. However, by adopting the configuration shown in FIG. 6, since the content data held in the memories 14 and 15 are all encrypted content data, a third party cannot use this memory 1 It is impossible to reproduce music data only with the data in 4 15 and there is no need to provide memory 14 5 in an expensive tamper-resistance module, reducing manufacturing costs. There is an advantage that it is done.

Also, in FIG. 6, the part included in the area TRM1 is an area where direct access from outside the memory card 110 is prohibited, and the part included in the area TRM2 is the area outside the memory card 110. This area is prohibited from being changed. In FIG. 6, for convenience, the region TRM1 and the region TRM2 are shown separately. It may be provided in one tamper resistance module.

[Distribution operation]

Next, an operation in each session of the data distribution system according to the first embodiment of the present invention will be described in detail with reference to flowcharts.

FIGS. 7, 8, and 9 are first, second, and third diagrams for explaining a distribution operation (hereinafter, also referred to as a distribution session) that occurs when content is purchased in the data distribution system according to the first embodiment. 3 is a flowchart of FIG.

7, 8, and 9 illustrate the operation when user 1 receives content data distribution from distribution server 30 via mobile phone 100 by using memory card 110. ing.

First, music selection is performed by the user 1 from the mobile phone 100 of the user 1 by operating the key buttons of the touch key unit 1108, and a distribution request is made. Further, the license purchase condition AC is input by operating a key button of the touch key section 110 (step S102).

Depending on the content delivery request from the mobile phone 1 0 0, the relay server 1 0 in the distribution server, to identify the requested down Rodosa ^ _ bar _{3 0} of interest to obtain the content. I, plaintext content The content data Data, the content ID, and the attached data are obtained via the LCM encoder 31.i of the download server 30.i and the corresponding LCM decoder 11.1.i (step S104). .

Here, the “attached data” includes title data, lyrics data, and singer name data of the content provided from the download server to the relay server 10, and may further include image image data of a jacket in which the content is stored. It is possible.

Subsequently, in the relay server 10 in the distribution server 30, the content ID, the license ID, the content decryption key Kc, the access control information AC1, and the reproduction in the relay server 10 are reproduced based on the license information AC and the attached data of the content. Circuit control information AC2 is generated (step S116).

The content ID on the relay server 10 is the same as the download server 30. It is possible to use the content ID of each download server obtained along with the content data Data from 1 to 30.n as it is, and it is also possible to generate it including the content ID of the download server. is there. Hereinafter, the content ID in the relay server 10 is simply referred to as a content ID.

Further, the distribution control unit 315 in the relay server 10 generates additional data Data-inf including the acquired attached data (step S118).

Subsequently, the encryption processing unit 308 in the relay server 1◦ encrypts the plaintext content data Data using the content decryption key Kc to generate encrypted content data {Data} Kc (step S120).

Referring to FIG. 8, distribution server 30 transmits a transmission request for {KPmc (x)} KPma to memory card 110 (step S130).

In the memory card 110, the authentication data holding unit 1400 outputs the authentication data {KPmc (l)} KPma in response to the distribution request (step S132). The mobile phone 100 transmits the authentication data {KPmc (l)} KPma received from the memory card 110 to the distribution server 30 (step S134).

The distribution server 30 receives the authentication data {KPmc (l)} KPma from the mobile phone 100 (step S136), and executes a decryption process using the authentication key Pma in the decryption processing unit 312 (step S138).

It is determined whether or not the public encryption key KPmc (l) encrypted with the authentication key KPma has been registered properly and whether or not the encryption has been performed properly (step S140), that is, If the data can be decrypted with the authentication key KPma and the subordinate data can be recognized in the decryption processing, the public encryption key KPmc (l) of the memory card 110 is accepted, and the flow shifts to step S142. On the other hand, if the decryption is not possible, or if the subordinate data cannot be recognized in the decryption processing, the public key KPmc (l) is not accepted and the processing is terminated without determining that the authentication key Kpma is not authenticated. Step S194).

Upon receiving the public encryption key KPtncd), the distribution control unit 315 generates a transaction ID for specifying the distribution session (step S142). Subsequently, the session key generator 316 generates a session key Ksl for distribution. Generate. The session key Ksl is decrypted by the encryption processing unit 318 using the public encryption key KPtnc (l) corresponding to the memory card 110 obtained by the decryption processing unit 312. (Step S144).

The transaction ID and the encrypted session key {Ksl} Kmc (l) are output to the outside via the data bus BS1 and the communication device 350 (step S146).

When the mobile phone 100 receives the transaction ID and the encrypted session key {Ks l} Kmc (l) (step S148), the mobile phone 100 transmits the memory interface 1200 to the memory card 110. The decryption processing unit 1444 decrypts the received data supplied to the data bus BS3 by using the memory card 110's unique secret decryption key Kmc (1) stored in the storage unit 1402 By processing, the session key Ksl is decrypted and extracted (step S150).

When confirming the acceptance of the session key Ks 1 generated by the distribution server 30, the controller 144 2 0 sends a session generated by the memory card 110 to the session key generation unit 144 18 during the distribution session. Instruct generation of key Ks2. The encryption processing unit 1406 is connected to the switching switch 144 via the contact Pc of the switching switch 1444 by the session key Ksl provided by the decryption processing unit 1404 via the contact Pa of the switching switch 1442. Encrypt session key Ks2 and public encryption key KPm (l) given by sequentially switching contact Pe and contact Pf of 6 and output {Ks2 {KPm (l)} Ksl to data bus BS3 Yes (Step S 1 5 2).

Note that the notation {X〃Y} Z indicates that data X and data それぞれ are data encrypted so that they can be decrypted with key それぞれ.

The data {Ks2〃KPm (l)} Ksl output to the data bus BS 3 is transmitted from the data bus BS 3 to the mobile phone 100 via the terminal 1 202 and the memory interface 1 200 (step In step S152, the mobile phone 100 attaches a transaction ID, and then the mobile phone 100 transmits the transaction ID to the distribution server 30 (step S154).

The distribution server 30 has the encrypted data transaction ID {{Ks2 // KPm (l)} Ks Receiving 1 and performing decryption processing of {Ks ² 〃KPm (l)} Ksl by the session key Ks 1 in the decryption processing section 320, the session key KS2 generated by the memory card and the memory card 1 10 unique The public encryption key KPm (l) is accepted (Step S156).

The encryption processing unit 326 transmits the content decryption key Kc, which is the license information, the reproduction circuit control information AC2, the license ID, the content ID, and the access control information AC1, to the public information unique to the memory card 110 obtained by the decryption processing unit 320. Encryption is performed using the open encryption key KPm (l) (step S164).

The encryption processing unit 328 receives the output of the encryption processing unit 326, and encrypts it using the session key Ks2 generated in the memory card 110 (step S166).

Referring to FIG. 9, the encrypted data {{Kc〃AC 2 〃license ID〃content ID〃ACl} Km (l)} Ks2 output from encryption processing section 328 is provided with a transaction ID, followed by a data bus. It is transmitted to mobile phone 100 via BS 1 and communication device 350 (step S168).

In this way, the session keys generated by the distribution server 30 and the memory card 110 are exchanged, the encryption is performed using the encryption keys received by each other, and the encrypted data is transmitted to the other party. With this, mutual authentication can be effectively performed even when each encrypted data is transmitted and received, and the security of the data distribution system can be improved.

The mobile phone 100 receives the transmitted transaction ID and the encrypted data {{Kc〃AC2〃license ID〃content ID〃ACl} Km (l)} Ks2, and stores only the encrypted data in the memory card 110. Enter (step S170). In the memory mode 110, the encrypted data provided to the data bus BS3 via the memory interface 1200 is decrypted by the decryption processing unit 1412. That is, the decryption processing unit 1412 decrypts the encoded data on the data bus BS3 using the session key Ks2 given from the session key generation unit 1418, and outputs it to the data bus BS4 (step S1). 74).

Kra (l) can be decrypted with the secret decryption key Km (l) stored in the The data {Kc〃AC2〃License ID〃Content ID〃ACl} Km (l) output to the data bus BS 4 is transmitted to the decryption processing unit 1422 by the secret decryption key Km (1) by the instruction of the controller 1420. The content is decrypted, and the content decryption key Kc, the playback circuit control information AC2, the license ID, the content ID, and the access control information AC1 are received (step S176).

Further, the content decryption key Kc, the playback circuit control information AC2, the license ID, the content ID, and the access control information AC1 are recorded in the empty j-th bank of the license information holding unit 1440 in the bank j (step S 1 78). Here, the natural number j is a number corresponding to the content data, and is l ^ j N (N: the total number of banks).

At the stage where the processing up to step S 178 has been completed normally, a transaction ID and a content data distribution request are transmitted from mobile phone 100 to distribution server 30 (step S 180).

Upon receiving the content data delivery request, the delivery server 30 encrypts the content data Data from the download server 30.i with the content decryption key Kc so that the encrypted content data {Data} Kc and The generated additional data DATA-inf is output via the data bus BS1 and the communication device 350 (step S182).

Mobile phone 100 receives {Data} Kc @ Data-inf, and receives encrypted content data {Data} Kc and additional data Data_inf (step S184). The encrypted content data {Data} Kc and the additional data Data-inf are transmitted to the data bus BS3 of the memory card 110 via the memory interface 1200 and the terminal 1202. In the memory card 110, the received encrypted content data {Data} Kc and the additional data Data-inf are recorded as they are in the memory 1415 (step S186).

Further, a notification of the transaction ID and the delivery receipt is transmitted from the mobile phone 100 to the delivery server 30 (step S188). When the delivery server 30 receives the delivery receipt (step S190), the delivery server 30 sends the notification to the charging database 302. The distribution end process is executed along with the storage of the billing data (step S192), and the entire process is executed. The processing is terminated (step SI94).

Note that the transaction ID is given to transmission and reception in a series of distributions, and is used to identify communication in the same distribution processing. In particular, although not shown, when the transaction ID can no longer be handled by the sender and the receiver, the distribution process ends there.

Through such processing, it is confirmed that the public encryption key KPm (l) transmitted from the content reproducing unit of the mobile phone 100 and the memory card 110 in response to the distribution request is valid, and Only because the content data can be transmitted to the user, it is possible to prohibit the distribution to unauthorized devices, thus improving the security of distribution.

According to the billing data recorded in the billing database, the price of the collected contents is distributed to the relay server 10 and the download servers 30.1 to 30.0.n. The download servers 30.1 to 30.0n are distributed based on the provided content.

In this way, if the content fee is collected by the relay server 10, if the user contracts with the relay server, the user does not need to individually contract with the other download servers 30.1 to 30 .n. Will be able to obtain various types of content under the same environment. In addition, for the content provider, it is possible to achieve the convenience that the content does not need to be provided to a plurality of download servers 30.1-30.0.n of different methods.

[Play operation]

Next, a reproduction operation for reproducing music from the encrypted content data stored in the memory card 110 in the mobile phone 100 and outputting the music to the outside (hereinafter, also referred to as a reproduction session) will be described. .

Referring to FIG. 10, a reproduction request is generated according to an instruction of user 1 from touch key unit 1108 of mobile phone 100 (step S200).

The mobile phone 100 responds to the generation of the reproduction request by the authentication data holding unit 15. From 00, the authentication data {KPp (l)} KPma that can be decrypted with the authentication key KPma is output to the data bus BS2 (step S202).

The encrypted data {KPp (l)} KPma for authentication is transmitted to the memory card 110 via the data bus BS2 and the memory interface 1200.

In the memory card 110, the encrypted data {KPp (l)} KPma for authentication transmitted to the data bus BS 3 via the terminal 1202 is taken into the decryption processing unit 1408. The decryption processing unit 1408 receives the authentication key KPma from the authentication key holding unit 1414, and performs a decryption process on the data on the data bus BS3 (step S204). The public encryption key KPp (l) encrypted with this authentication key KPma is registered properly and has been subjected to regular encryption, that is, it can be decrypted with the authentication key KPma and occurs at the time of decryption. If the dependent data can be recognized (step S206), the public encryption key KPp (l) is accepted as the result of the authentication by the authentication key KPma has been approved, and the process proceeds to step S210.

On the other hand, if the decryption is not possible, or if the dependent data generated in the decryption process cannot be recognized (step S206), the process ends assuming that the authentication result using the authentication key KPma is unapproved (step S240).

When the controller 1420 receives the public encryption key KPp (l) unique to the content playback circuit of the mobile phone 100 in the decryption processing unit 1408, and as a result of the authentication, the mobile phone 100 is approved as the content playback device The transmitted public encryption key KPp (l) is determined to be the public encryption key assigned to the content reproduction circuit approved for this data distribution system, and the session key generation unit 1418 sends the reproduction session The generation of the session key Ks 3 in is instructed via the data bus BS 4. The session key Ks 3 generated by the session key generation unit 1418 is sent to the encryption processing unit 1410. The encryption processing unit 1410 encrypts the session key Ks3 with the public encryption key KPp (l) of the mobile phone 100 obtained by the decryption processing unit 1408, and transmits the encrypted data {Ks3} Kp (l) to the data bus. Output to BS 3 (step S210).

Mobile phone 100 receives encrypted data {Ks 3} Kp (l) on data bus BS via terminal 1 202 and memory interface 1200. Encrypted data {Ks3} Kp (l) is decrypted by decryption processing section 1504, and session key Ks3 generated in memory card 110 is received (step S212).

Controller 1106, in response to accepting session key Ks3, instructs session key generator 1508 via data bus BS2 to generate session key Ks4 generated by mobile phone 100 in the playback session. I do. The generated session key Ks4 is sent to the encryption processing unit 1506, and {Ks4} Ks3 encrypted by the session key Ks3 obtained by the decryption processing unit 1504 is output to the data bus BS2 (step S 214).

The encrypted session key {Ks4} Ks3 is transmitted to the memory card 110 via the memory interface 1200. In the memory card 110, the encrypted session key {Ks4} Ks3 transmitted to the data bus BS3 is decrypted by the decryption processing unit 1412, and the session key Ks4 generated by the mobile phone 100 is received (step S 216).

In response to receiving the session key Ks4, the controller 1420 checks the access control information AC1 stored in the bank j for storing the corresponding content ID in the license holding unit 1440 (step S218).

In step S218, by confirming the access control information AC1 which is information relating to the restriction on the access to the memory, if it is already in the reproduction disabled state, that is, the lower part of the access control information AC1 is "00". If the content ID to be reproduced is not recorded in the license holding unit 1440, the reproduction session is terminated (step S240), and if the reproduction is possible but the number of times of reproduction is limited, that is, the lower order of the access control information AC1 is lower. In the case of "FE" to "01", the data of the access control information AC1 is updated (decreased by one), and after the number of reproducible times is updated, the process proceeds to the next step S222 (step S220). On the other hand, if the reproduction is possible and the number of times of reproduction is not limited, step S220 is skipped, and the process shifts to the next step S222 without updating the access control information AC1.

If it is determined in step S218 that the playback is possible in the playback session, the content decryption key Kc and the playback circuit control information AC2 of the playback request music stored in the bank j of the license holding unit 1440 are stored. Where to get The processing is executed (step S2222).

The obtained content decryption key Kc and reproduction circuit control information AC2 are sent to the encryption processing section 144 through the contact point Pd of the switching switch 1444. The encryption processing unit 1446 receives the license decryption key Kc received from the data bus BS4 by using the session key Ks4 received from the decryption processing unit 1412 via the contact Pb of the switching switch 1442. Then, the reproduction circuit control information AC2 is encrypted, and the encrypted data {Kc〃AC2} Ks4 is output to the data bus BS3 (step S224).

The encrypted data output to the data bus BS3 is transmitted to the mobile phone 100 via the terminal 122 and the memory interface 120.

In the mobile phone 100, the encrypted data {Kc〃AC2} Ks4 transmitted to the data bus BS 2 via the memory interface 1200 is subjected to decryption processing by the decryption processing unit 1510, The content decryption key Kc and the reproduction circuit control information AC2 are received (step S226). The decryption processing section 1510 transmits the content decryption key Kc to the decryption processing section 1516, and outputs the reproduction circuit control information AC2 to the data bus BS2.

The controller 1106 receives the reproduction circuit control information AC2 via the data bus BS2, and checks whether or not reproduction is possible (step S228).

In step S232, if the reproduction circuit control information AC2 determines that reproduction is impossible, the reproduction session is terminated (step S240).

On the other hand, if playback is possible, the encrypted content data {Data} Kc of the requested music recorded in the memory from the memory card 110 is output to the data bus BS3, and the terminal 1 202 and the memory The information is transmitted to the mobile phone 100 via the interface 1200 (step S230).

In the mobile phone 100, the encrypted content data {Data} Kc output from the memory card 110 and transmitted to the data bus BS2 is decrypted by the decryption processing unit 1516 using the content decryption key Kc. In this way, plain data of the content can be obtained (step S232). The decrypted plaintext content data Data is reproduced as music by the music reproduction unit 1518, and the music reproduced outside via the mixing unit 1525 and the terminal 1530 is output (step S15). 2 3 4), The process ends (step S240).

Also in the playback session, the mobile phone 100 and the memory card 110 exchange the generated encryption keys, respectively, and execute the encryption using the encryption keys received by each other. Send the encrypted data to the other party. As a result, mutual authentication can be performed in each transmission and reception of data in the reproduction session, as in the case of the distribution session, and the security of the data distribution system can be improved.

Further, in the present invention, the case where the content is supplied to the user via the mobile phone network has been described. However, the same effect can be obtained when the content is supplied to the user via the Internet or the like. The relay server 10 in FIG. 2 transmits the license data obtained from the download servers 30.1 to 30.n via the corresponding LCM decoders 11.1 to 11.n to the respective license servers. The same memory capacity as the memory card attached to the memory card writer 72 connected to the personal computer 70 serving as the user terminal via the distribution control unit 12, the Internet network 40, and the provider 50 Encrypted content data and license information may be supplied to the memory card 112 with the configuration shown in FIGS. 6, 7, and 8. At this time, the mobile phone 100 in FIGS. 6, 7, and 8 may be replaced with a personal computer 70.

Therefore, in the data distribution system according to the present invention, when the content data is supplied to the user, the copyright is protected through an information communication network such as the Internet or an information communication network such as a mobile phone network. While protecting, it is possible to supply the user with content data such as content music data supplied by a plurality of download servers having different copyright protection schemes.

[Modification of Embodiment 1]

Operations in each session of the data distribution system according to the modification of the first embodiment of the present invention will be described in detail with reference to flowcharts.

FIGS. 11, 12, and 13 are first, second, and third flow charts for explaining distribution operations that occur when content is purchased in the data distribution system according to the modification of the first embodiment. It is. 11, FIG. 12 and FIG. 13 also describe the operation when user 1 receives content data distribution from distribution server 30 via mobile phone 100 by using memory card 110. .

First, music is selected by the user 1 from the mobile phone 100 of the user 1 by operating the key buttons of the touch key section 1108, and a request is made. Further, the license purchase condition AC is input by operating the key button of the touch key 1108 (step S102).

In response to a content distribution request from the mobile phone 100, the relay server 10 in the distribution server transmits the plaintext content data Data of the requested content and the content ID and attached data in the download server to the download servers 30, 1 to Of the 30.n, they are received from the target download server 30.i, and are acquired via the corresponding LCM decoder 11.1.i (step S104).

Here, the distribution control unit 315 determines the corresponding content decryption key Kc in the license database 302 according to the download server from which the content data is transmitted and the content ID acquired from the download server. A search is performed to determine whether the file exists (step S106).

If the content decryption key Kc corresponding to the content exists (step S108), the process proceeds to step S114. On the other hand, if the content decryption key Kc corresponding to the content does not exist (step S108), the process proceeds to the next step S110.

If the content decryption key Kc corresponding to the content does not exist, the relay server 10 in the distribution server 30 generates a content ID and a content decryption key Kc based on the attached data of the content (step S1). Ten) .

In addition, the download server and the content obtained from the download server

The ID, the generated content ID, and the content decryption key Kc are registered in the license database 302 (step S112), and the process proceeds to step S116 '.

On the other hand, if the content decryption key Kc corresponding to the content exists, The content ID and the content decryption key Kc in the relay server 10 corresponding to the content are acquired from the license database 302 (step S114), and the process proceeds to step S116 '.

In step S116 ', the distribution server 30 and the relay server 10 generate the license ID, access control information AC1, and reproduction circuit control information AC2 based on the license information AC and the data attached to the content. (Step S116). Further, distribution control section 315 in relay server 10 generates additional information Data-inf including the acquired attached data (step S118).

Subsequently, the encryption processing unit 308 in the relay server 10 encrypts the plaintext content data Data using the content decryption key Kc to generate encrypted content data {Data} Kc (step S120).

Hereinafter, the processing in FIGS. 12 and 13 is the same as the processing in FIGS. 8 and 9, and therefore, description thereof will not be repeated.

If such processing is performed, since the content ID and the content decryption key Kc for the same content data distributed from the distribution server 30 are the same, the above-described “copying” of the content data is performed. At a later time, for example, when the user of the copy receives only the distribution of the content decryption key Kc, the reproduction process can be performed.

In the above description, the memory 1415 has been described as being provided in an area outside the TRM. However, there is no problem even if the memory 1415 is provided in the TRM.

While this invention has been described and illustrated in detail, this has been done by way of example only and is not intended to be limiting; it is apparent that the spirit and scope of the invention is limited only by the appended claims. Will be appreciated.

Claims

The scope of the claims

1. A data information communication network (40) for transmitting content data encrypted by a plurality of corresponding first predetermined encryption schemes from a plurality of content data suppliers,

In response to a content distribution request from the first user terminal, the content data requested by the first user terminal is received from the data information communication network, and encrypted and distributed by a second predetermined encryption method. And a distribution relay server (30) for performing

The delivery relay server,

A plurality of first content data decryption means (11) for decrypting the content data encrypted by the plurality of first predetermined encryption methods from the plurality of content data supply sources; . 1— 1 1. N)

Content data encryption means (3110) for receiving the output of the first content data decryption means, encrypting the content data with the second predetermined encryption method, and generating encrypted content data;

A transmitting means (350) for distributing the encrypted content data.

2. The distribution relay server, in response to a content distribution request from the first user terminal connected to a mobile phone network, encrypts the content data encrypted by the second predetermined encryption method. And deliver

2. The data distribution system according to claim 1, wherein the transmission unit distributes the encrypted content data via the mobile phone network.

3 · The distribution relay server:

With respect to license information including at least a content decryption key for decrypting the encrypted content data, encryption that can be decrypted in the first user terminal by a secret decryption key held in the first user terminal Further comprising a first encryption means for performing

The transmission means further distributes the encrypted license information. The data distribution system described in 1. ,

4. The first user terminal comprises:

A data storage unit that stores the encrypted content data and the license information, inputs and outputs the license information in a state where the license information is displayed, and is detachable from a data playback device.

The data storage unit includes:

First storage means for storing the encrypted content data and outputting the encrypted content data to the outside of the data storage unit in response to a request from outside the data storage unit; and A second storage unit capable of storing the license information corresponding to the encrypted content data,

4. A control unit for outputting at least a part of the license information stored in the second storage unit to the outside of the data storage unit in accordance with a request from outside the data storage unit. Data distribution system as described.

5. The data storage unit is:

Holds a certificate for certifying the security of the data storage unit encrypted so that the validity can be determined using a predetermined authentication key, and holds authentication data that can output the certificate to the outside Part further,

The delivery relay server comprises:

5. The data distribution system according to claim 4, further comprising an approval unit that determines a validity of the certificate output from the data storage unit.

6. The data storage unit is:

Means for decoding at least a part of the license information stored in the second storage means,

The data distribution system according to claim 4, wherein at least a part of the license information is encrypted and output to the outside of the data storage unit in accordance with a request from outside the data storage unit.

7. The first user terminal comprises:

Receiving the encrypted content data and the license information stored in the data storage unit, decrypts the encrypted content data and reproduces the content data. A data reproducing unit for performing

The data reproducing unit,

Data control means for requesting the data storage unit to output at least a part of the license information and to output the encrypted content data;

A content data decryption unit that decrypts the encrypted content data according to the content decryption key and outputs the content data;

5. The data distribution system according to claim 4, further comprising: content data reproducing means for reproducing the content data.

8. The data according to claim 3, wherein the first encryption unit encrypts the content decryption key with a first encryption key transmitted in advance by being encrypted from the first user terminal. Delivery system.

9. The content transmitted by the data information communication network and encrypted by the corresponding first predetermined encryption method from one of the plurality of content data suppliers and the corresponding content supplier. Further comprising a second user terminal for receiving data,

The second user terminal comprises:

2. The data distribution system according to claim 1, further comprising a second content data decrypting unit configured to decrypt the content data encrypted by the first predetermined encryption method.

10. In response to a content distribution request from a user terminal, a distribution relay that selects one from a plurality of content data supply sources to acquire content data, and transmits the acquired content data to the user terminal. A server,

In order to receive, from a plurality of content data suppliers, content data encrypted by a corresponding plurality of first predetermined encryption schemes, the first data information communication network (40) communicates with the first data information communication network (40). First transmission / reception means (3 0 1) for transmitting / receiving data;

A plurality of first components for decrypting the content data decrypted by the plurality of first predetermined encryption methods from the plurality of content data sources; . 1— 1 1. N) Content data encryption means (3110) which receives an output of any one of the plurality of first content data decryption means, encrypts the content data with the second predetermined encryption method, and generates encrypted content data. ) When, '

A second transmitting / receiving means for receiving a content distribution request from the user terminal and transmitting / receiving data to / from the user terminal via a second data communication network in order to transmit the encrypted content data; 2 0)

A content data source capable of providing the content data specified by the content distribution request from the user terminal is selected from the plurality of content data sources, and the selected content data source is selected from the selected content data sources. Receiving the content data encrypted by a first predetermined encryption method corresponding to the content data source, and corresponding to the selected content data source among the plurality of first content data decryption units; The content data is decrypted by content data decryption means corresponding to a first predetermined encryption method.

2. A distribution relay server for transmitting the encrypted content data encrypted by the content encryption means to the user terminal.

11. The distribution relay server according to claim 10, wherein the second data communication network is a mobile phone network.

1 2. The delivery relay server,

According to a content distribution request from the user terminal, transmitting license information including at least a content decryption key for decrypting the encrypted content data,

10. The distribution relay server according to claim 10, wherein the second transmission unit further transmits the encrypted license information.

1 3. The delivery relay server,

First encryption means (32 6) for performing encryption capable of being decrypted in the user terminal using a secret decryption key held in the user terminal,

10. The distribution relay server according to claim 10, wherein the second transmission / reception unit further distributes the encrypted license information.

14 4. The content distribution request is sent to the Including a certificate that can be judged

The delivery relay server,

Comprising authentication means for determining the validity of the certificate,

14. The distribution relay server according to claim 13, wherein when the authenticity is confirmed by the authentication unit, one of the encrypted content data and the license information is transmitted.