JP2004046431A - Portable radio-telephone set and content download data back up method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To preserve data of quantity exceeding capacity of an incorporated recording part and to securely protect a content with copyright in a portable radio telephone set. <P>SOLUTION: A plaintext content distributed from a content distribution server is recorded in a recording part 5. When a transmission instruction of the desired plaintext content is given to an outer recording unit 14 from a key operation part 11, it is read from the recording part 5, is ciphered by a cipher text content generation part 17 by using a secret key from a secret key generation part 21 and it is transmitted to the outer recording unit 14 as a cipher text content so as to be recorded. When a reading instruction of the content is given from a key operation part 11, the cipher text content is read from the outer recording unit 14 and is decoded by a cipher text content decoding part 18 by using a decoding secret key from the secret key generation part 21. It is supplied to a plaintext content reproducing part 25 through a RAM 9 and is displayed on a display part 26 and the like. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a portable wireless telephone that stores plaintext content such as document information in a built-in recording unit and can reproduce the content data of the plaintext content on a display unit or the like. The present invention relates to a method for backing up content download data of a portable wireless telephone which enables backup of stored plaintext content.
[0002]
[Prior art]
The portable wireless telephone has a built-in user memory for a dial function, a telephone directory function, and the like. However, with the expansion of packet communication in recent years, social needs for transmitting and receiving more information have been increasing, and an increase in the storage capacity has been desired. For this purpose, as described in Japanese Patent Application Laid-Open No. 9-107397, a method of using an external memory detachable from a portable wireless telephone is known. Such an external memory is suitable for storing various content distributions.
[0003]
However, when a plurality of content distributions are accumulated, the data amount becomes enormous. In order to accumulate various content distributions, it is desirable to utilize an external recording device having a larger storage capacity.
[0004]
Japanese Patent No. 2919400 discloses an example of a technique for connecting to an external recording device having such a large storage capacity. This is such that a personal computer or a digital camera is used as an external recording device of the portable radio telephone, and the portable radio telephone and the external recording device can be connected and data can be transmitted and received between them. The function of the portable wireless telephone is improved.
[0005]
[Problems to be solved by the invention]
In recent years, some content distributions have copyrights. From the viewpoint of such copyright protection, it is impossible to transmit copyrighted content or content regarded as copyrighted to an external device. Therefore, in a mobile wireless phone with a small data storage capacity, if you want to obtain new content beyond the storage capacity, you have to delete the previously stored content. Even without erasing and abandoning, new content cannot be obtained. Also, if the mobile phone being used breaks down, it will not be possible to recover the acquired content, or if the model of the mobile phone is changed, the acquired paid content will not be restored to the new model. For example, the portable radio telephone cannot be used, and the content acquired by the individual has to be abandoned or paid again to acquire the paid content.
[0006]
From this point of view, the prior art described in Japanese Patent Application Laid-Open No. 2000-313388 includes a portable radiotelephone equipped with an encryptor and a data leakage prevention means for encrypting the distributed audio data. To increase the memory. In this prior art, a user determines whether encryption is necessary or not, and if necessary, saves the data in a built-in or detachable non-volatile memory. Then, audio data is read out from the nonvolatile memory as necessary, and reproduced from a speaker.
[0007]
In this case, if the data is stored in the built-in memory, the illegal leakage of paid contents can be prevented, and even if the removable memory is a detachable mechanism dedicated to the portable wireless telephone, the illegal leakage can also be prevented. easy.
[0008]
However, there is a problem that the number of memories increases because the size of the memory attached to the portable wireless telephone is limited. Therefore, when storing a large amount of paid contents, it is conceivable to use an external recording device such as a large-capacity personal computer or a digital camera instead of the nonvolatile memory as described above. If audio data is stored and read out to external storage devices one by one, the location for using such audio data is limited, and it is extremely difficult to use this audio data anytime and anywhere. Difficult.
[0009]
Still another conventional technique is described in JP-A-2001-44983. This is because the encrypted music data and the encryption key distributed from the server are re-encrypted with the unique ID of the portable wireless telephone to obtain ID encrypted data, and the ID encrypted data is sent to an external music reproducing apparatus, The playback device obtains the unique ID from the portable wireless telephone, decrypts the ID encrypted data into encrypted music data and an encryption key, and further decrypts the encrypted music data with an encryption key to reproduce the music. This is a method that enables playback on a device. Such a unique ID can be obtained by requesting this from the music playback device, or can be obtained from the portable wireless telephone by using an IC card or the like, and can be used in the music playback device.
[0010]
According to this conventional technique, music information can be enjoyed while protecting the copyright distributed from the server by an external music reproducing device. Then, the music data can be stored in the music reproducing apparatus itself.
[0011]
However, according to the conventional technique, it is possible to acquire, from the portable wireless telephone, the unique ID of the portable wireless telephone used to encrypt the ID together with the ID encrypted data from the portable wireless telephone. Therefore, it is not enough in terms of copyright and privacy protection. Of course, this means that the music information received by the portable radio telephone is acquired by the music reproducing device as the external device, and the music is enjoyed.
[0012]
Also, considering the portability, if it is possible to carry out the necessary data from among many data stored in the external device rather than carrying the music playback device as an external device, the Although convenience is improved, such points are not considered.
[0013]
SUMMARY OF THE INVENTION An object of the present invention is to solve such a problem, and to enable backup of content recorded in a built-in recording unit having a relatively small recording capacity, and prevent copyright and privacy infringement of the content. The present invention relates to a portable wireless telephone and a content download data backup method thereof.
[0014]
[Means for Solving the Problems]
In order to achieve the above object, a portable wireless telephone according to the present invention has a recording unit for storing plaintext content, and an output unit for displaying the plaintext content stored in the recording unit, enabling connection of an external recording device, Secret key generation means for generating secret keys for encryption and decryption, and content data of the plaintext content read from the recording unit using the secret key for encryption generated by the secret key generation means. Encryption processing means for performing encryption processing to generate ciphertext content, transmitting means for transmitting the ciphertext content from the encryption processing means to an external recording device for recording, and ciphertext content from the external recording device. Receiving means for receiving, and decrypting the ciphertext content received by the receiving means using the decryption secret key generated by the secret key generating means, and decrypting the plaintext content It provided a decoding means for generating over data, and makes it possible displays the content data decoded by the decoding means at the output.
[0015]
A plaintext content receiving unit that can communicate with the content distribution server and a plaintext content recording control unit that controls writing of the received data of the plaintext content receiving unit to the recording unit are provided, and the plaintext content stored in the recording unit is The plaintext content is distributed from the distribution server and received by the plaintext content receiving unit.
[0016]
Also, e-mail information created by the user for transmission via the telephone line, or e-mail information received via the telephone line is recorded in a recording unit or other recording means, and the e-mail information The above processing is performed as plain text content.
[0017]
The secret key generation means generates a secret key based on a telephone number unique to the telephone, generates a secret key based on input information from the input means, and generates the secret key based on the first input information. The secret key is determined.
[0018]
Further, the encryption processing means includes a plaintext content reading unit that reads the content data of the plaintext content from the recording unit, and an error detection code generation unit that generates and adds an error detection code to the content data read from the recording unit. A ciphertext content generation unit for encrypting the content data to which the error detection code has been added using the encryption secret key generated by the secret key generation means, and generating ciphertext content. The decryption unit decrypts the ciphertext content received from the external recording device by the receiving unit using the decryption secret key generated by the secret key generation unit, and converts the content data into an error detection code. The ciphertext content decryption unit that generates plaintext content data with the A decoded data error detection unit that detects the error using the error detection code added to the data, and a plaintext content rewriting unit that writes the plaintext content data from the decoded data error detection unit to a recording unit or a dedicated memory. The content data written in the recording unit or the dedicated memory by the plaintext content rewriting unit is supplied to the output unit.
[0019]
The ciphertext content generation unit includes x (where x is an integer of 2 or more) encryption algorithms and a random number generator, and each time content data of plaintext content is read from the recording unit or a dedicated memory. Selecting an encryption algorithm for encrypting the content data read out of the x number of encryption algorithms based on a random number generated by the random number generator; An algorithm number analysis unit for detecting an encryption algorithm at the time of encryption processing of the ciphertext content obtained, and x number of decryption algorithms individually corresponding to the x number of encryption algorithms. A decryption algorithm for decrypting ciphertext content received from among x decryption algorithms based on the detection result It is intended to select a.
[0020]
In order to achieve the above object, a content download data backup method for a portable radio telephone according to the present invention is for backing up plaintext content recorded in a recording unit built in the portable radio telephone, and is read from the recording unit. The plaintext content data is encrypted based on the encryption secret key generated in the mobile wireless telephone to form ciphertext content, and only the ciphertext content is transmitted to an external recording device for recording. Receiving the ciphertext content transmitted from the external recording device, and decrypting the received ciphertext content based on the decryption secret key generated in the mobile wireless telephone corresponding to the encryption secret key. This generates plaintext content data through the conversion process and displays the data on the output unit.
[0021]
The plaintext content is plaintext content distributed from a content distribution server or electronic mail information transmitted and received via a telephone line.
[0022]
The secret key for encryption and the secret key for decryption are generated based on a telephone number unique to the portable radio telephone.
[0023]
Further, the secret key for encryption and the secret key for decryption are determined by the information input first time from the input means.
[0024]
The content data encryption process is performed based on an encryption algorithm selected based on a random number generated by a random number generator from among a plurality of encryption algorithms. , A decryption algorithm corresponding to the encryption algorithm used at the time of encrypting the encrypted content is selected from the decryption algorithms, and the decryption algorithm is performed based on the selected decryption algorithm.
[0025]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a schematic configuration of a first embodiment of a portable radio telephone and a data backup method thereof according to the present invention, wherein 1 is a content distribution server, 2 is a portable radio telephone, 3 is a plaintext content receiving unit, Is a plain text content recording control unit, 5 is a recording unit, 6 is an encryption / decryption processing unit, 7 is a transmission / reception unit, 8 is an external recording device connection unit, 9 is a RAM (Random Access Memory), 10 is an output unit, 11 Denotes an input unit, 12 denotes a plaintext content management unit, 13 denotes an external recording device management unit, and 14 denotes an external recording device.
[0026]
In FIG. 1, a content distribution system is configured by a content distribution server 1 and a portable wireless telephone 2, and an external recording device 14 for data backup can be detachably connected to the portable wireless telephone 2. .
[0027]
In the mobile wireless telephone 2, the plaintext content receiving unit 3 has a function of receiving a plaintext content distributed from the content distribution server 1 as well as a receiving function as a normal mobile wireless telephone. (A duplexer), an RF receiving / transmitting unit, and a wireless unit including a frequency synthesizer (PLL). That is, it has transmission / reception as a normal portable wireless telephone, transmission of a download instruction to the content distribution server 1, and reception of plaintext content from the content distribution server 1.
[0028]
The plaintext content recording control unit 4 performs channel decoding of the received plaintext content based on a command from the plaintext content management unit 12, and performs recording control in the recording unit 5. These are built in a DSP (Digital Signal Processor).
[0029]
The plaintext content management unit 12 instructs the plaintext content recording control unit 4 to allocate the recording area of the received (downloaded) data of the various plaintext contents to the recording unit 5, and assigns an identifier to the plaintext content recording control unit 5. The recording section 5 manages a list of plaintext contents in correspondence with the recording location.
[0030]
In response to a download request from the mobile wireless telephone 2, the content distribution server 1 wirelessly distributes the requested plaintext content to the mobile wireless telephone 2. Such plaintext content is at least partially composed of information including document information expressed in plaintext, and may be accompanied by visible data such as image data or audio data such as music. In some cases. The data including the document information and the accompanying image data and audio data are the content data representing the information content of the plaintext content, and the plaintext content is added with the name and type of the content.
[0031]
The mobile radiotelephone 2 has a built-in recording unit 5 having a relatively large recording capacity, such as a flash memory. The plaintext content received from the content distribution server 1 by the plaintext content receiving unit 3 is converted to the plaintext content. Under the control of the management unit 12, the recording is performed in the recording unit 5 by the recording control of the plaintext content recording control unit 4. In this manner, the plaintext content downloaded from the content distribution server 1 is recorded in the recording unit 5. By operating the input unit 11 such as a keyboard or the like as a button operation unit, the user can select a desired content from the recording unit 5. The plaintext content can be read out, and the readout plaintext content is supplied to the output unit 10 including the display unit and the audio output unit via the RAM 9 and output as an image, a text, a sound, and the like. That is, the output unit 10 and the input unit 11 form an interface unit with the user.
[0032]
Further, the portable radio telephone 2 is provided with an external recording device connection unit 8 for detachably connecting to the external recording device 14. The external recording device 14 connected in this way is used as a backup memory of the recording unit 5. As the external recording device 14, a personal computer with a built-in hard disk having a sufficiently large recording capacity is preferable, but a device capable of storing data, such as a magnetic tape recording / reproducing device or a magnetic or optical disk recording device, may be used. Further, two or more external recording devices 14 can be connected to the portable wireless telephone 2, and what kind of external recording device 14 is connected is managed by the external recording device management unit 13. .
[0033]
The plaintext content recorded in the recording unit 5 can be transmitted to the external recording device 14 and recorded by a user's instruction operation of the input unit 11. That is, when the plaintext content designated by the user is read from the recording unit 5 when the content is protected by copyright or when privacy protection is required, the encryption / decryption processing unit 6 and transmitted as an encrypted text content from the external recording device connection unit 8 to the external recording device 14 by the transmission / reception unit 7. In the external recording device 14, the ciphertext content is recorded and stored while being encrypted.
[0034]
In this way, the plaintext content downloaded from the content distribution server 1 is recorded and stored in the external recording device 14. The content stored in each external recording device 14 is also managed by the plaintext content management unit 12. Therefore, by displaying the management information on the output unit 10, the user can know what plain text content is stored in which external recording device 14. The user can know which external recording device 14 is connected to the portable wireless telephone 2 by displaying the management information of the external recording device management unit 13 on the output unit 10.
[0035]
When the content desired to be reproduced on the external recording device 14 is designated by the input unit 11 from the management information as described above, the content specified by the external recording device 14 is read out from the external recording device 14 and transmitted, and the portable wireless communication is performed. In the telephone 2, this is received by the transmission / reception unit 7 via the external recording device connection unit 8. When the received content is a ciphertext content, the received content is decrypted by the encryption / decryption processing unit 6 and recorded in the RAM 9 as plaintext content data. The RAM 9 may have a recording capacity of about 1 to 3 plaintext contents. The plaintext content recorded in the RAM 9 is supplied to the output unit 10 and reproduced and output as video or audio.
[0036]
In the above description, the plaintext content is protected by the copyright. However, the content which is not protected by the copyright is recorded and stored in the external recording device 14 without being encrypted by the encryption / decryption processing unit 6. You may. Therefore, such plaintext content read from the external recording device 14 is recorded in the RAM 9 without being subjected to decryption processing after being received by the transmission / reception unit 7.
[0037]
Although the above is the plain text content downloaded from the content distribution server 1, the e-mail received by the plain text content receiving unit 3 via a telephone line (not shown) or the e-mail transmitted via the telephone line Can be handled in the same way as plain text content, and can be recorded as encrypted content on the external recording device 14 as in the case of plain text content described as being downloaded so far. The data can be read, decoded, and reproduced and output by the output unit 10. Therefore, in the following description, the plaintext content includes not only the plaintext content downloaded from the content distribution server 1 but also such content as an electronic mail unless otherwise specified. Note that such electronic mail information may be recorded together with the plain text content downloaded by the recording unit 5, or a recording unit dedicated to mail may be provided and recorded on this.
[0038]
Here, the recording unit 5 is composed of a flash memory or the like, and when the recording capacity is full, the plaintext content cannot be newly recorded. In order to record on this, the recording section 5 must be completely erased once. However, when all erasure is performed in this way, even necessary plaintext content is erased. The external recording device 14 is for backing up the recording unit 5, and records the desired plaintext content recorded in the recording unit 5 in the external recording device 14 before erasing the entire recording unit 5. be able to. When the content is stored in this manner, plaintext content protected by copyright or plaintext content such as an e-mail requiring privacy protection is converted into ciphertext content by the encryption / decryption processing unit 6. Things. At this time, only the ciphertext content is stored in the external recording device 14. The encryption key, that is, the encryption key is unique to the portable wireless telephone 2 as a secret key, and is not sent to the external recording device 14. For this reason, the ciphertext content stored in the external recording device 14 as described above cannot be decrypted by any device other than the portable radio telephone 2, and is output from the external recording device connection unit 8 of the portable radio telephone 2. Encrypted content is protected from being illegally decrypted or tampered with.
[0039]
FIG. 2 is a block diagram showing the configuration of the mobile wireless telephone 2 in FIG. 1 more specifically, where 7a is a content transmitting unit, 7b is a content receiving unit, 8a is a transmitting side connecting unit, 8b is a receiving side connecting unit, 15 is a plaintext content reading unit, 16 is an error detection code generation unit, 17 is a ciphertext content generation unit, 18 is a ciphertext content decryption unit, 19 is a decrypted data error detection unit, 20 is a plaintext content rewriting unit, 21 is A secret key generation unit for encryption / decryption, 22 a plaintext content erasing unit, 23 and 24 signal lines, 25 a plaintext content reproducing unit, 26 a display unit, 27 an audio output unit, 28 a path, Components corresponding to those in FIG. 1 are denoted by the same reference numerals, and redundant description will be omitted.
[0040]
In FIG. 1, an output unit 10 serving as an interface with a user in FIG. 1 includes a plaintext content reproduction unit 25, a display unit 26, and an audio output unit 27 such as a speaker. The display unit 26 displays an operation mode, a menu, plaintext contents, and the like, similarly to a normal portable wireless telephone. The audio output unit 27 performs voice reproduction for a call similar to that of a normal portable wireless telephone. The sound reproduction of the plaintext content is also performed. The display unit 26 and the audio output unit 27 output video / audio using the plaintext content reproduction unit 25, that is, the reproduction signal converted by the audio / image codec.
[0041]
1 is a button operation unit such as a keyboard or a touch panel on the display unit 26 (hereinafter, the input unit 11 is referred to as the button operation unit 11), and is used for content distribution. A request for downloading the content to the server 1 (FIG. 1), an instruction to reproduce the content distributed and stored in the recording unit 5, an instruction to transmit plaintext content such as the recording unit 5 to the external recording device 14, and an instruction to the external recording device 14 This is used by the user to perform an operation such as an instruction to receive plaintext content from the user.
[0042]
The transmitting / receiving unit 7 in FIG. 1 includes a content transmitting unit 7a and a content receiving unit 7b, and the external recording device connecting unit 8 in FIG. 1 includes a transmitting side connecting unit 8a connected to the content transmitting unit 7a. And a receiving-side connecting unit 8b connected to the content receiving unit 7b.
[0043]
The encryption / decryption processing unit 6 in FIG. 1 includes an encryption processing unit and a decryption processing unit. The encryption processing unit includes a plaintext content reading unit 15 for reading the plaintext content Cp from the recording unit 5, an error detection code generation unit 16 for generating and adding an error detection code to the plaintext content, and an error detection code added. And a ciphertext content generation unit 17 for encrypting the plaintext content using the secret key for encryption generated by the secret key generation unit 21 to generate the ciphertext content. The generation unit 17 is connected to the content transmission unit 7a.
[0044]
Here, the plaintext content Cp is composed of information such as its name, content type, copyright information, and content data. The name of the plaintext content includes a file name and a file number assigned to the plaintext content Cp, and is also used for specifying the plaintext content Cp when requesting download. The type of content represents the type of data (content data) of the plaintext content Cp such as a text, a photo, a moving image, and music. When the plaintext content Cp is protected by copyright, information indicating that fact (ie, copyright information) is added. The content data is the content of a content such as a sentence, a photograph, a moving image, and music.
[0045]
When the user instructs the button operation unit 11 to transmit the desired plaintext content Cp in the recording unit 5 to the external recording device 14, the plaintext content reading unit 15 reads the content data of the plaintext content Cp specified from the recording unit 5. If it is output and protected by copyright, the above processing is performed by the error detection code generator 16 and the ciphertext content generator 17 to generate ciphertext content. The ciphertext content is transmitted from the transmission-side connection unit 8a to the external recording device 14 by the content transmission unit 7a. In the case of plaintext content Cp that is not protected by copyright, after the content data is added with an error detection code by the error detection code generation unit 16, the content data is sent to the content transmission unit 7a via the signal line 23, and the external recording device 14 is transmitted.
[0046]
Note that the plaintext content Cp stored in the recording unit 5 is managed by the plaintext content management unit 12 as described above, and under this management, the plaintext content readout unit 15 reads out the plaintext content from the recording unit 5. It is determined whether or not the content Cp is protected by copyright.
[0047]
The same is true for plaintext contents such as e-mails. In this case, the ciphertext contents generation unit 17 determines whether or not to encrypt the contents by the user's instruction operation on the button operation unit 11. .
[0048]
Furthermore, the encrypted text content recorded on the external recording device 14 is also managed by the plaintext content management unit 12.
[0049]
Incidentally, for example, the display unit 26 displays the recording status of the plaintext content in the recording unit 5 based on the management information of the plaintext content management unit 12. As a result, the user can determine whether or not new plaintext content can be downloaded at present. The user determines that the state is close to a state where downloading is impossible (or the plaintext content management unit 12 may automatically detect this, and notify the user with the display unit 26 or the like), and perform button operation. When the user operates the unit 11 to instruct the recording unit 5 to record (transfer) the necessary plaintext content to the external recording device 14, the recording to the external recording device 14 is performed as described above. When the plaintext contents required by the recording unit 5 are recorded and stored in the external recording device 14, the plaintext contents are backed up by the external recording device 14. The plaintext content at 5 becomes unnecessary. Then, when the user completes the transfer of the plaintext content to the external recording device 14 and performs a predetermined operation with the button operation unit 11 assuming that the flat content in the recording unit 5 is no longer necessary, the plaintext content erasing unit 22 Operates to perform a batch erasure of the recording section 5. As a result, the recording unit 5 can record the plaintext content, and the new plaintext content can be downloaded.
[0050]
When the plaintext content erasing unit 22 erases the recording unit 5 in accordance with an instruction from the button operation unit 11, the plaintext content erasing unit 22 notifies the plaintext content management unit 12 that the recording unit 5 has been erased. As a result, the plaintext content management unit 12 clears the management information on the recorded content in the recording unit 5 and, when a new plaintext content is received, records the new plaintext content in the recording unit 5. 4 can be given instructions.
[0051]
The decryption processing unit of the encryption / decryption processing unit 6 decrypts the ciphertext content received by the content receiving unit 7b using the decryption secret key Key generated by the secret key generation unit 21. A ciphertext content decryption unit 18; a decrypted data error detection unit 19 for detecting an error in the plaintext content decrypted by the ciphertext content decryption unit 18 using an error detection code added thereto and performing error correction; Further, in the case where the decrypted plaintext content is recorded in the recording unit 5, a plaintext content rewriting unit 20 for rewriting to the recording unit 5 is provided.
[0052]
When the user performs a predetermined operation with the button operation unit 11, a list of ciphertext contents recorded in each external recording device 14 is displayed on the display unit 26 based on the management information of the plaintext content management unit 12, A desired plaintext content can be selected and designated from these. In this case, the external recording device management unit 13 manages the currently connected external recording device 14, and under the management, the list of the currently connected external recording device 14 is displayed on the display unit 26. Will be displayed.
[0053]
Therefore, when the user designates a desired content recorded in the external recording device 14 by the button operation unit 11, the designated content is transmitted from the designated external recording device 14, and the portable radio telephone 2 transmits the designated content to the receiving side connection unit. 8b is received by the content receiving section 7b. If the received content is ciphertext content, the above-described processing is performed by the ciphertext content decryption unit 18 and the decrypted data error detection unit 19 to become plaintext content, and the received content is encrypted. If the content is not plain text content, it is processed only by the decrypted data error detection unit 19 and written into the RAM 9. When the writing in the RAM 9 is completed, the written plaintext content is read by the plaintext content reproducing unit 25, and is supplied to the display unit 26 and the audio output unit 27 to output the plaintext content.
[0054]
It should be noted that the content received from the external recording device 14 may be recorded in the recording unit 5 by the plaintext content rewriting unit 20 after processing such as decryption. In this case, the recording area of the plaintext content in the recording unit 5 is designated and recorded by the plaintext content management unit 12, and when the recording is completed, the plaintext content that has just been recorded is read out via the RAM 9. Is supplied to the plaintext content reproducing unit 25 and is reproduced by the display unit 26 and the audio reproducing unit 27. Therefore, even if the content received from the external recording device 14 is recorded not in the RAM 9 but in the recording unit 5, the content can be reproduced and displayed immediately after the recording.
[0055]
By the way, if the content received from the external recording device 14 is to be recorded in the recording unit 5, if the recording unit 5 is full at that time, it is not possible to record in the recording unit 5. Cannot import content from Therefore, in such a case, the user notifies the recording unit 5 that the recording unit 5 is full using the display unit 26 or the like before taking in the plaintext content from the external recording device 14, and instructs the recording unit 5 to operate in response to the user's instruction operation. The necessary plaintext content is transferred to the external recording device 14, and the plaintext content designated by the user is taken from the external recording device 14 after the recording unit 5 is erased by the plaintext content erasing unit 22.
[0056]
Next, the operation of the first embodiment will be described.
[0057]
FIG. 3 is a flowchart illustrating a specific example of an operation relating to recording of plaintext content in the recording unit 20.
[0058]
2 and 3, when the user operates the button operation unit 11 to request download of a desired plaintext content (S101), the content distribution server 1 (FIG. 1) transmits the plaintext content requested by the portable radio telephone 2. The Cp is distributed to the portable wireless telephone 2 as information including a content name, a content type, and plaintext content data (S102).
[0059]
Then, the plaintext content receiving unit 3 receives the plaintext content Cp (S103), and displays a message such as “received and saved” and the name of the plaintext content on the display unit 26 together with the termination of the incoming call. Then, the user is prompted to confirm that the user has downloaded the desired plaintext content (S104). At the same time, the plaintext content management unit 12 causes the name of the downloaded plaintext content Cp, the type of the content, and whether or not the copyright is protected. Is registered (S105). Based on this, the plaintext content management unit 12 instructs the plaintext content recording control unit 4 on the recording area of the plaintext content Cp in the recording unit 5. Accordingly, the plaintext content recording control unit 4 records the name of the plaintext content Cp, the type of the content, the copyright information, and the content data in the recording area specified by the plaintext content management unit 12 in the recording unit 5. (S106).
[0060]
Thus, a series of operations is completed (S109). When the user operates the button operation unit 11 to give an instruction to display the plaintext content (S107), the recording unit 5 transmits the content of the plaintext content Cp. The data is read out and supplied to the display unit 26 and the audio output unit 27 via the RAM 9 and the plain text content reproduction unit 25 for display. Then, the display is terminated by the operation of the button operation unit 11 by the user, and a series of operations is terminated (S109). When this operation is an erasing instruction (S110), the recording unit 5 performs batch erasing of all data. (S111), a series of operations ends (S109).
[0061]
FIG. 4 is a flowchart showing a specific example of a processing procedure for transmitting the plaintext content Cp from the recording unit 5 to the external recording device 14 in FIG.
[0062]
2 and 4, in the mobile wireless telephone 2, when a transmission instruction to the external recording device 14 is given by the user operating the button operation unit 11 (S201), the plaintext content registered in the plaintext content management unit 12 is transmitted. Is displayed on the display unit 26 in a selectable manner (S202). At the same time, the secret key generation unit 21 starts creating a secret key for encryption (S203).
[0063]
When the user operates the button operation unit 11 to select and select a desired plaintext content Cp displayed on the display unit 26 (S204), the plaintext content management unit 12 deletes the designated plaintext content Cp of the recording unit 5 from the designated plaintext content Cp. The recording area is selected and notified to the plaintext content reading unit 15 (S205). Then, based on the management information of the external recording device management unit 13, a list of the external recording devices 14 currently connected to the portable wireless telephone 2 is displayed on the display unit 26 (S206), and the plaintext content Cp is selected from the list. Is selected by the user.
[0064]
When the user operates the button operation unit 11 to select a desired external recording device 14 (S207), the plaintext content name and type selected by the plaintext content management unit 12, the size (data amount) of the content data, and S207. The identifier of the selected external recording device 14 is registered (S212). Here, the identifier of the external recording device 14 is uniquely set by the portable radio telephone 2 for each external recording device 14, and the identifier can be used to access the corresponding external recording device 14. That is, all identifiers of the external recording device 14 that can be used for the portable radio telephone 2 are registered in the portable radio telephone 2.
[0065]
At the same time, the plaintext content reading unit 15 reads the content data of the plaintext content Cp specified and selected by the user from the recording area selected by the plaintext content management unit 12 in S205 of the recording unit 5 (S208). The read content data is added with the error detection code generated by the error detection code generation unit 16 (S209), and when the plaintext content Cp is protected by copyright, the encrypted text content is further added. The generation unit 17 performs an encryption process using the secret key for encryption generated by the secret key generation unit 21 (S203) (S210), and further encrypts the error detection code added thereto (S210). S211).
[0066]
The name and type of the plaintext content Cp registered in the plaintext content management unit 12 are added to the encrypted content data in plaintext to form ciphertext content (S213), and the content is transmitted. The data is transmitted from the transmission side connection unit 8a to the external recording device 14 selected in S207 by the unit 7a (S214). In the external recording device 14, the ciphertext content is recorded and stored (S215). If the plaintext content Cp designated and selected is not protected by copyright, the process proceeds from S209 to S213, and the encryption process is not performed.
[0067]
The above processing is the same when the plaintext content is an electronic mail, and the electronic mail may be recorded in the recording unit 5 or may be recorded in another recording unit (not shown). . In the case of an e-mail recorded in another recording unit, the e-mail read from this is supplied to the error detection code generation unit 16 and the same processing is performed. When performing the encryption processing (S210, S211), the user operates the button operation unit 11 to specify.
[0068]
By the way, the secret key for encryption, which is generated when a transmission instruction to the external recording device 14 is issued (S201), is generated by the secret key generation unit 21. Is generated based on the information of For example, when a telephone number is used as unique information, it is assumed that the secret key is obtained by rearranging numeric arrays forming the telephone number according to a predetermined rule. For example, assuming that the telephone number is “09012345678” and the predetermined rule is to reverse the arrangement of the numbers forming the telephone number, the secret key Key is “87654321090”. By doing so, the secret key Key is generated to be paired with the telephone number.
[0069]
Note that the size (data amount) of the content data is also registered in the plaintext content management unit 12 in S212. For example, when the content recorded on the external recording device 14 is reproduced, it is used to determine whether the content has been tampered with. Is what you do.
[0070]
Since the name and type added to the content recorded in the external recording device 14 are plain text (S213), these can be displayed on the external recording device 14 such as a personal computer, for example. The encrypted content data cannot be decrypted by the external recording device 14 because the encryption private key Key used for the content data is not transmitted to the external recording device 14, and therefore, the external recording is not performed. The device 14 cannot disclose the content of the content data. The same applies when the ciphertext content is read from the external recording device 14 by another portable wireless telephone. Therefore, the external recording device 14 can protect the content protected by the copyright and the privacy content from a third party while backing up the recording unit 5 of the portable wireless telephone 2.
[0071]
In the processing procedure described with reference to FIG. 4, the transmission instruction of the plaintext content to the external recording device 14 (S 201) is performed by the portable wireless telephone 2, but the transmission command can be issued from the external recording device 14. It is. That is, a list of information on the names and types of the plaintext contents managed by the plaintext content management unit 12 via the path 28 can be browsed by the external recording device 14. Then, the necessary plaintext content is selected from the list on the external recording device 14 side, and the selection result is sent to the plaintext content management 12 via the path 28. Based on this, the plaintext content management unit 12 As described above, the plaintext content selected by the recording unit 5 is transmitted to the external recording device 14. In this case, when all the necessary plaintext contents in the recording unit 5 are to be transferred to the external recording device 14, the plaintext content erasing unit 22 is operated by the instruction from the external recording device 14 to collectively Let it be erased.
[0072]
FIG. 5 is a flowchart showing a specific example of a processing procedure when a desired content is reproduced from the external recording device 14.
[0073]
2 and 5, when the user instructs the reading of the content from the external recording device 14 with the button operation unit 11 of the portable radio telephone 2 (S301), the plain text content is set based on the management information of the external recording device management unit 13. Among the information managed by the management unit 12, the external recording devices 14 currently connected to the portable radio telephone 2 and the names and types of contents recorded therein are displayed on the display unit 26 in a selectable manner in a list format. Is performed (S302). When the user sees this and instructs selection of the desired content (S303), the selected content is notified to the plaintext content management unit 12. The plaintext content management unit 12 having received this notification accesses the corresponding external recording device 14 via the path 28 with the identifier, and notifies the external storage device 14 of the content designated by the user (S305).
[0074]
The external recording device 14 that has received the notification reads out the content of the corresponding name and type and transmits it to the mobile wireless telephone 2. When the mobile radiotelephone 2 receives the content by the content receiving unit 7b (S306), if the content is the ciphertext content, the mobile radiotelephone 2 uses the decryption secret key Key (S304) generated by the secret key generation unit 21. After the content data is decrypted by the ciphertext content decryption unit 18 (S307) and the error detection code is decrypted (S308). The error detection unit 19 performs an error detection and correction process, and writes the data in the RAM 9 or the recording unit 5 as described above. When recording in the recording unit 5, the plaintext content management unit 12 specifies a recording area in the recording unit 5 (S313), and the name, type, and recording area of the decrypted plaintext content are the plaintext content. The information is registered as management information in the management unit 12 (S314).
[0075]
When the recording in the RAM 9 or the recording unit 5 is completed, the data amount (size) of the recorded plaintext content data is detected, and the plaintext content registered in the plaintext content management unit 12 in S212 of FIG. The data amount of the content data is compared with the data amount, and it is determined whether or not the plaintext content has been tampered with, and whether the plaintext content is not plaintext content encrypted by another portable wireless telephone (S309). . If they have been tampered with, the data amounts will not match. If the content is plaintext encrypted by another portable wireless telephone, it cannot be decrypted. If the plaintext content has not been tampered with and has been encrypted by the portable radio telephone 2, the plaintext content is read from the RAM 9 or the recording unit 5 and displayed on the display unit 26 or the audio output unit 27 (S310). If it has been tampered with (S309), a message to the effect that illegal processing has been performed is displayed on the display unit 26 or the like (S311), and the processing ends (S312).
[0076]
If the external recording device 14 is also used as a backup for other portable wireless telephones, the user can copy plaintext content recorded from another portable wireless telephone with his / her portable wireless telephone 2. In some cases, it can be read. However, if the read plain text content is encrypted text content encrypted by another portable wireless telephone, it cannot be decrypted. Therefore, in this case, the user is notified on the display unit 26 that decoding is not possible.
[0077]
Further, in the processing procedure described with reference to FIG. 5, the content reading instruction (S301) from the external recording device 14 is performed on the mobile wireless telephone 2 side, but the external recording device 14 can also perform the reading instruction. It is. That is, a list of information on the names and types of contents in the external recording device 14 managed by the plaintext content management unit 12 via the path 28 can be browsed by the external recording device 14. Then, the external recording device 14 selects contents as necessary from this list and sends the selection result to the plaintext content management 12 via the path 28. Based on this, the plaintext content management unit 12 2 is set to a state in which reception processing is possible.
[0078]
As described above, in the first embodiment, since a device having a large recording capacity can be used as the external recording device 14, copyright protection is possible even if a large number of copyrighted plaintext contents are obtained. In addition, even personal information of a user can be safely stored without infringing privacy.
[0079]
By the way, in the first embodiment, the secret key Key is automatically created using the unique ID of the portable wireless telephone 2. Therefore, if the mobile radio telephone 2 is lost or damaged, or if the mobile radio telephone is replaced, the content recorded on the external recording device 14 cannot be reproduced. In order to prevent this, if the secret key of the ciphertext content to be sent to the external recording device 14 can be arbitrarily created by the user himself, instead of relying on the portable radio telephone 2. In the event of loss or the like, the content data in the external recording device 14 can be utilized.
[0080]
FIG. 6 shows a portable radiotelephone according to the second embodiment of the present invention in which a private key can be arbitrarily created by a user and a data backup method for the portable radiotelephone according to the second embodiment. Is a flow chart showing a specific example of a processing procedure when sending a message.
[0081]
Here, a series of processing procedures of S201, S202, and S204 to S215 are the same as the processing procedures shown in FIG. 4, and a description thereof will be omitted. In the second embodiment, in the processing procedure shown in FIG. 4, the processing procedures of S401 to S405 are performed instead of S203. Here, the processing procedure of S401 to S405 will be described.
[0082]
2 and 6, when the user instructs the transmission of the content to the external recording device 14 by operating the button operation unit 11 (S201), the secret key for encryption, such as a telephone number, is unique to the mobile wireless telephone 2. The display unit 26 inquires whether to create based on the ID or arbitrarily create by the user (S401). When the user instructs to create a key based on the unique ID of the mobile wireless telephone 2 (S402), the secret key generation unit 21 uses this unique ID to generate an encryption key Key for encryption, as in the procedure shown in FIG. Is created (S403), and used for encrypting the content data of the plaintext content Cp read from the recording unit 5 or the like and the error detection code added thereto (S210, S211).
[0083]
When the user instructs to create an arbitrary secret key (S402), the user inputs an arbitrary secret key Key using the button operation unit 11 (S404). Then, the content data and the error detection code are encrypted with the secret key (S210, S211).
[0084]
In this way, when the method of arbitrarily determining the secret key by the user is selected in S402, thereafter, only the secret key determined at that time can be used for the portable wireless telephone 2. Disappears. Of course, the selection leg (S402) of the method of creating based on the unique ID of the portable wireless telephone 2 remains.
[0085]
The secret key arbitrarily determined by the user is limited to one time only (S405), and the secret key is managed by a CPU (not shown) or the like. This means that if multiple arbitrary private keys can be created, the probability that the private key will leak to the third party increases, and if any of these leaks to the third party, the third party will distribute it. The obtained content can be used from the external recording device 14 free of charge. That is, the copyright is unduly infringed. Therefore, the creation of an arbitrary secret key Key is limited to only one time so that it can be used without copyright infringement.
[0086]
When reading the ciphertext content using the arbitrary secret key Key from the external recording device 14, an operation similar to that of FIG. 5 is performed. In other words, the decryption key is also an arbitrary private key determined by the user, and generates a unique private key Key to perform decryption processing.
[0087]
FIG. 7 is a flowchart showing a processing procedure for reading from the external recording device 14 with respect to writing to the external recording device 14 in FIG.
[0088]
Here, a series of processing procedures of S301 to S303 and S305 to S312 are the same as the processing procedures shown in FIG. 5, and a description thereof will be omitted. In the processing procedure shown here, the processing procedure of S501 to S505 is performed instead of S304 in the processing procedure shown in FIG. Here, the processing procedure of S501 to S505 will be described.
[0089]
2 and 7, when the user operates the button operation unit 11 of the portable wireless telephone 2 to instruct reading of the content from the external recording device 14 (S301), the secret key for encrypting the content is: The display unit 26 displays a screen for inquiring whether the ID is created based on an ID unique to the portable wireless telephone 2 such as a telephone number or arbitrarily determined by the user (S501). Then, when the user gives an instruction to create a secret key Key based on the ID unique to the mobile wireless telephone 2 (S502), the secret key generation unit 21 decrypts the decryption key based on the unique ID in the same manner as the processing shown in FIG. A key is created (S503).
[0090]
By the way, even if the method of creating the secret key Key is specified as being based on the unique ID of the portable wireless telephone 2, the ciphertext content taken in from the external recording device 14 is created based on the unique ID. In some cases, the data is not encrypted with the encryption private key Key, but is encrypted with the secret key arbitrarily created by the user (S404 in FIG. 6). Therefore, in the second embodiment, for example, at the beginning of the ciphertext content, information that, when correctly decoded, obtains a fixed pattern is added, and the pattern in the content decoding process (S307) is added. If it is obtained, the decryption process is continued with this secret key Key. However, if such a pattern cannot be obtained, it is determined that the method of forming the secret key specified at this time (S501) is incorrect, and the process returns to S501 and the secret key is returned. The method for creating the key Key is selected again.
[0091]
Therefore, as described above, in accordance with the user's designation (S501), a secret key Key is created based on the ID unique to the portable wireless telephone 2 (S503), and this is used to correctly decrypt the ciphertext content read from the external recording device 14. When the secret key is an encryption private key, the decryption process of the ciphertext content is performed using the secret key (S307, 308), but the secret key does not correspond to the encryption secret key. In this case, the user is again requested to select a secret key creation method (S501). This time, the user selects to create a secret key determined by the user (S502), and waits for the input of the secret key by the user (S504). When the secret key input by the user matches the secret key Key that is input and managed in S404 of FIG. 6 as described above, decryption processing is performed using this (S307, S308). In this case, as described above, the ciphertext content specified by the user from the external recording device 14 is read once as described above, but is read again in order to perform decryption processing using the correct secret key Key. It is. When the secret key input by the user does not match the managed secret key Key, the input of the secret key is requested again (S405).
[0092]
If there is no secret key arbitrarily determined by the user in the processing shown in FIG. 6, the same processing as in FIG. 5 is performed, and the process immediately proceeds to S503 together with the readout instruction (S301) of the external recording device 14, and the portable radio telephone 2. A secret key Key is created based on the unique ID.
[0093]
It should be noted that, for each ciphertext content recorded in the external recording device 14 by the plaintext content management unit 12, whether the secret key is also based on the ID unique to the mobile wireless telephone 2 or is determined uniquely by the user. When the ciphertext content is specified in the external recording device 14 in S302, the secret key forming method may be automatically determined from the management information of the plaintext content management unit 12. In FIG. 7, in this case, in S501, the method of creating the secret key is determined based on the management information of the plaintext content management unit 12 based on the designation result of S302, and when the secret key is created using the ID unique to the mobile wireless telephone 2 ( In step S502, the process proceeds to step S503, where the secret key is created. If the secret key is arbitrarily created by the user (step S502), the user is instructed to input the secret key determined in step S404 in FIG. 6 (step S502). S504).
[0094]
As described above, in the second embodiment, even if the portable wireless telephone 2 is lost or damaged and cannot be used, or even if the portable wireless telephone is replaced, the user can use the secret key arbitrarily determined by the user. By doing so, it is possible to use the encrypted text content by the secret key in the external recording device 14 with another portable wireless telephone or a replacement portable wireless telephone.
[0095]
Further, if an arbitrary private key Key determined by the user is leaked to a third party, the third party may perform an operation to illegally use the pay content with another portable radio telephone. However, if the other portable wireless telephone does not share the external recording device 14, the identifier registered to access the external recording device 14 is also necessary as described in S305 of FIG. In addition, since this identifier is uniquely determined by the portable radio telephone 2 based on the information on the external recording device 14, it is not easy to access the external recording device 14, and it is difficult to access the external recording device 14. It is not easy to use authorized ciphertext contents. Therefore, the convenience of using many pay contents while protecting copyright is improved.
[0096]
FIG. 8 is a block diagram showing a main part of a third embodiment of a portable radio telephone and a data backup method thereof according to the present invention, wherein 29 is a random number generator, 30 is an algorithm number analysis unit, and corresponds to FIG. The same reference numerals are given to the same parts, and duplicate description will be omitted.
[0097]
In the third embodiment, the encryption strength is improved to make decryption and falsification more difficult than in the previous embodiments. The configuration is the same as the configuration shown in FIG. A plurality of encryption methods can be selected by the generation unit 17, and accordingly, a plurality of decryption methods can be selected by the ciphertext content decryption unit 18.
[0098]
In the figure, the ciphertext content generation unit 17 is set with x (where x is an integer of 2 or more) encryption algorithms 1, 2, ..., x, and a random number generator 29 is generated. One of them is selected according to the random number, and the plaintext content Cp from the error detection code generation unit 16 is selected by the selected encryption algorithm i (where i = 1, 2,...) Using the encryption secret key Key. , X) and are encrypted. Therefore, an encryption algorithm i is assigned an algorithm number that matches one of the random numbers generated by the random number generator 29, and if the random number generated by the random number generator 29 matches one of the algorithm numbers, The encryption algorithm i corresponding to the algorithm number is selected.
[0099]
The ciphertext content decryption unit 18 has x decryption algorithms 1, 2,..., X corresponding to the encryption algorithms 1, 2,. , And the same algorithm numbers as the corresponding encryption algorithms 1, 2,..., X are assigned to the decryption algorithms 1, 2,. Further, an algorithm number analysis unit 30 is provided for analyzing which of the encryption algorithms 1, 2,..., X in the ciphertext content generation unit 17 has encrypted the ciphertext content from the external recording device 14. When the algorithm number of the encryption algorithm of the ciphertext content is known, a decryption algorithm i corresponding to the algorithm number in the ciphertext content decryption unit 18 is selected, and the encryption algorithm is determined by the decryption secret key Key. The plaintext content is processed and decrypted according to the selected decryption algorithm i.
[0100]
The configuration other than this is the same as that of the previous embodiment, and as the encryption algorithm used here, for example, DES (Data Encryption Standard) can be used.
[0101]
Next, the operation of the third embodiment will be described.
[0102]
FIG. 9 is a flowchart showing a processing procedure when sending the plaintext content Cp read from the recording unit 5 (FIG. 2) to the external recording device 14.
[0103]
This processing procedure of the third embodiment shown in FIG. 9 is different from the processing procedure shown in FIG. 4 in that one of a plurality of encryption algorithms 1, 2,. S601 to S604, which are processing procedures for selection, are added, and an algorithm number is added to the registration information to the plaintext content management unit 12 (FIG. 2) in S212. Note that FIG. 9 shows the processing procedure from S203 and S208.
[0104]
As in the description of FIG. 4, when the user instructs the button operation unit 11 (FIG. 2) to transmit the plaintext content to the external recording device 14 (S201 in FIG. 4), steps S202 to S207 shown in FIG. After that, the content data of the plaintext content Cp is read from the recording unit 5 (FIG. 2) (S208), and an error detection code is added by the error detection code generation unit 16 (FIG. 2) (S209). The sentence content generation unit 17 is supplied.
[0105]
In the above process, a random number has started to be generated from the random number generator 29 (S601), and matches one of the algorithm numbers of the encryption algorithms 1, 2,..., X in the ciphertext content generation unit 17. Until a random number is obtained, random number generation is continued (S601 to S603). If the random number matches one of the algorithm numbers i, the encryption algorithm i to which the algorithm number i is assigned is selected and determined for execution (S604).
[0106]
When the content data of the plaintext content Cp is supplied from the error detection code generation unit 16 to the ciphertext content generation unit 17 in such a state, the ciphertext content generation unit 17 performs the following according to the selected encryption algorithm i. The content data is encrypted using the encryption secret key Key (S210), and the error detection code added to the content data is encrypted (S211). At the same time, in addition to the name and type of the plaintext content Cp and the identifier of the external recording device 14, the plaintext content management unit 12 (FIG. 2) also displays the algorithm number i of the encryption algorithm i used in the encryption process. The registration information is registered (S212), and the registration information is added to a predetermined position (for example, in the header of the packet) of the encrypted content data as plain text (S213). Then, the ciphertext content obtained by such processing is transmitted to the external recording device 14 (S214), and is recorded on the external recording device 14 (S215).
[0107]
In the third embodiment, the transmission instruction to the external recording device 14 may be issued by the button operation unit 41 of the portable wireless telephone 2 as described above. In the same manner as described above, it may be possible to make it possible from the external recording device 14.
[0108]
FIG. 10 is a flowchart showing a processing procedure of the ciphertext content received from the external recording device 14.
[0109]
The processing procedure of the third embodiment shown in FIG. 10 is different from the processing procedure shown in FIG. 5 in that the corresponding one of the plurality of decoding algorithms 1, 2,. S701 to S704, which are processing procedures for determining one, are added. FIG. 10 shows the processing procedure from S304 and S306.
[0110]
Similarly to the description of FIG. 5, when the user gives an instruction to read out the plaintext content from the external recording device 14 using the button operation unit 11 (FIG. 2) (S301 in FIG. 5), steps S302 to S305 shown in FIG. 5 are executed. After that, the ciphertext content is received from the external recording device 14 (S306), and the name and type of the plaintext added in S213 of FIG. 9 are extracted from the received ciphertext content, and the plaintext content management unit 12 ( 12) is notified (S701).
[0111]
Further, the algorithm number analysis unit 30 extracts the algorithm number i added in S213 of FIG. 9 from the ciphertext content (S702), and the algorithm number registered in the plaintext content management unit 12 in S212 of FIG. And (S703). If they do not match, a message indicating that the illegal processing has been performed is displayed on the display unit 26 (FIG. 2) or the like (S311), and the processing ends (S312). It is determined that the data is encrypted by the mobile wireless telephone 2, and the decryption algorithm i to which the algorithm number is assigned is selected by the ciphertext content generation unit 18 (S704).
[0112]
In the following, the processes after S307 described in FIG. 5 are performed according to the selected decoding algorithm i.
[0113]
In the third embodiment, the reading instruction from the external recording device 14 may be issued by the button operation unit 41 of the portable radio telephone 2 as described above. In the same manner as described above, it may be possible to make it possible from the external recording device 14.
[0114]
As described above, in the third embodiment, since the encryption algorithm is randomly different for each ciphertext content transmitted to the external recording device 14, the encryption strength is lower than in the previous embodiment. This further improves the decryption and falsification of the ciphertext content recorded on the external recording device 14.
[0115]
【The invention's effect】
As described above, according to the present invention, since a built-in recording unit is backed up using an external recording device having a large recording capacity, a large amount of downloaded or received content can be stored. In addition, since the ciphertext content is encrypted by the portable radio telephone and only the ciphertext content is stored in the external recording device 14, even copyrighted distribution content violates copyright. The backup data can be stored and managed on an external recording device as backup data, and even the contents of the user can be stored on the external recording device without fear of infringement of privacy. The convenience of the wireless telephone is further improved.
[Brief description of the drawings]
FIG. 1 is a diagram showing a schematic configuration of a first embodiment of a portable radio telephone and a data backup method thereof according to the present invention.
FIG. 2 is a block diagram more specifically showing the configuration of the mobile radio telephone in FIG.
FIG. 3 is a flowchart illustrating a specific example of a processing procedure relating to recording of contents in a recording unit in FIG. 2;
FIG. 4 is a flowchart illustrating a specific example of a processing procedure for transmitting content from a recording unit to an external recording device in FIG. 2;
FIG. 5 is a flowchart showing a specific example of a processing procedure when a desired content is reproduced from the external recording device in FIG. 2;
FIG. 6 is a flowchart illustrating a specific example of a processing procedure for transmitting content from a recording unit to an external recording device in a second embodiment of the portable wireless telephone and the data backup method thereof according to the present invention.
7 is a flowchart showing a specific example of a processing procedure for reading content from the external recording device with respect to writing of the content to the external recording device shown in FIG. 6;
FIG. 8 is a configuration diagram showing a main part of a third embodiment of the portable radio telephone and the data backup method thereof according to the present invention, and is a configuration diagram of the third embodiment.
FIG. 9 is a flowchart showing a specific example of a processing procedure when sending plaintext content read from the recording unit to the external recording device 14.
10 is a flowchart showing a specific example of a processing procedure for ciphertext content received from an external recording device with respect to the processing procedure shown in FIG. 9;
[Explanation of symbols]
1 Content distribution server
2 Mobile radiotelephone
3 Plaintext content receiver
4 Plaintext content recording control unit
5 Record section
6 Encryption / decryption processing unit
7 Content transmission / reception unit
7a Content transmission unit
7b Content receiver
8 External recording device connection
8a Transmission side connection
8b Receiver connection
9 RAM
10 Output section
11 Button operation part (input part)
12 Plaintext Content Management Department
13 External recording device management unit
14 External recording device
15 Plaintext content reading unit
16 Error detection code generator
17 Ciphertext Content Generator
18 Ciphertext content decryption unit
19 Decoded data error detector
20 Plaintext content rewriting unit
21 Secret key generator
22 Plaintext Content Erasing Department
25 Plaintext Content Playback Department
26 Display
27 Audio output section
29 random number generator
30 Algorithm number analysis unit

Claims (12)

In a portable wireless telephone having a recording unit for storing plaintext content download data as plaintext content, and an output unit for reproducing and displaying the plaintext content stored in the recording unit, to which an external recording device can be connected,
Secret key generation means for generating secret keys for encryption and decryption,
A cipher for encrypting the content data of the plaintext content read from the recording unit using the secret key for encryption generated by the secret key generation means, and generating ciphertext content download data. Conversion processing means;
Transmitting means for transmitting the ciphertext content download data from the encryption processing means as ciphertext content to the external recording device for recording,
Receiving means for receiving ciphertext content from the external recording device;
Decryption processing means for decrypting the ciphertext content received by the reception means using the decryption secret key generated by the secret key generation means to generate content data of plaintext content Wherein the plaintext content data obtained by decryption processing by the decryption processing means can be reproduced and displayed on the output unit. In claim 1,
A plaintext content receiving unit capable of communicating with a content distribution server, and a plaintext content recording control unit that controls writing of the received data of the plaintext content receiving unit to the recording unit are provided.
The portable wireless telephone according to claim 1, wherein the plaintext content stored in the recording unit is plaintext content distributed from the content distribution server and received by the plaintext content receiving unit. In claim 1,
E-mail information created by the user to transmit via the telephone line, or e-mail information received via the telephone line is recorded in the recording unit or other recording means,
A portable wireless telephone, wherein the electronic mail information is the plaintext content. In any one of claims 1 to 3,
The portable wireless telephone according to claim 1, wherein said secret key generation means generates said secret key based on a unique telephone number. In any one of claims 1 to 3,
The portable wireless telephone according to claim 1, wherein the secret key generation means generates the secret key based on input information from the input means, and determines the secret key based on the first input information. In any one of claims 1 to 5,
The encryption processing means includes:
A plaintext content reading unit that reads content data of plaintext content from the recording unit;
An error detection code generation unit that generates and adds an error detection code to the content data read from the recording unit;
A ciphertext content generation unit that performs encryption processing on the content data to which the error detection code has been added using the encryption secret key generated by the secret key generation unit, and generates the ciphertext content; Consisting of
The decryption processing means,
The ciphertext content from the external recording device received by the receiving unit is decrypted using the decryption secret key generated by the secret key generation unit, and an error detection code is added to the content data. A ciphertext content decryption unit that generates the added plaintext content data,
A decoded data error detection unit that detects an error in the content data from the ciphertext content decryption unit using the error detection code added to the content data;
A plaintext content rewriting unit for writing the plaintext content data from the decrypted data error detection unit to the recording unit or a dedicated memory, wherein the plaintext content rewriting unit performs the recording unit or the dedicated memory. Supplying the content data written to the output unit to the output unit. In claim 6,
The ciphertext content generation unit,
x (where x is an integer of 2 or more) encryption algorithms and a random number generator,
Each time content data of the plaintext content is read from the recording unit or the dedicated memory, the content read out of the x encryption algorithms based on a random number generated by the random number generator. Select an encryption algorithm to encrypt the data,
The decryption processing means,
An algorithm number analyzer for detecting an encryption algorithm at the time of encryption processing of the received ciphertext content, and x number of decryption algorithms individually corresponding to the x number of encryption algorithms,
A portable radio telephone, wherein a decryption algorithm for decrypting the received ciphertext content is selected from among the x decryption algorithms based on a detection result of the algorithm number analysis unit. A download data backup method for plaintext content recorded in a recording unit built in a mobile wireless telephone,
The content data of the plaintext content read from the recording unit is subjected to an encryption process based on a secret key for encryption generated in the portable wireless telephone to obtain ciphertext content. Record on an external recording device,
The ciphertext content transmitted from the external recording device is received, and the received ciphertext content is determined based on a decryption secret key generated in the portable wireless telephone corresponding to the encryption secret key. A decryption process for generating plaintext content data, and reproducing and displaying the content data on an output unit. In claim 8,
The content download data backup method for a portable wireless telephone, wherein the plaintext content is plaintext content distributed from a content distribution server or electronic mail information transmitted / received via a telephone line. In claim 8 or 9,
The content download data backup method for a portable radio telephone, wherein the encryption private key and the decryption private key are generated based on a telephone number unique to the portable radio telephone. In claim 8, 9 or 10,
A method for backing up content download data of a portable radio telephone, wherein the secret key for encryption and the secret key for decryption are determined based on information first input from input means. In any one of claims 8 to 11,
The encryption process of the content data is performed based on an encryption algorithm selected based on a random number generated by a random number generator from among a plurality of encryption algorithms,
The decryption processing of the ciphertext content selects, from among a plurality of decryption algorithms, the decryption algorithm corresponding to the encryption algorithm used when encrypting the encrypted content, and the selected decryption algorithm is selected. A content download data backup method for a portable radio telephone, which is performed based on the decryption algorithm.

Images