JP4420622B2 - How to send and receive data - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a data transmission / reception method, and more particularly to a transmission / reception method in which a large amount of information can be safely used using the Internet.
[0002]
[Prior art]
For example, when a distance learning is performed using a public line communication network such as the Internet, a large amount of information needs to be transmitted and received. Since it takes a long time to transmit and receive this using a communication line in a communication system such as a narrow band, it is practically impossible. Therefore, a method of distributing preprinted text to users (students) can be considered. However, since text content is not input to the terminal on the user side, transmission / reception of information such as lesson content with the professor side (server) is restricted, and there is a problem that the functions of the Internet cannot be fully utilized. Therefore, for example, a method is conceivable in which text is stored in a large-capacity storage medium such as a CD, distributed to the user in advance and input to the user terminal, and then communicated with the server (teacher side). However, a large-capacity storage medium such as a CD can be easily copied in the same manner as a printed matter, and there is a problem that it is not possible to prevent the content from being spread.
[0003]
[Problems of the Invention]
In order to prevent duplication of the CD, a method such as setting a duplication lock or encrypting the contents so that the contents are not clarified even after duplication is adopted. It is known and a safety problem arises.
[0004]
SUMMARY OF THE INVENTION An object of the present invention is to provide a method capable of safely transmitting and receiving data using a large-capacity external recording medium such as a CD.
[0005]
[Means for solving problems]
In order to solve the above-described problems, in the present invention, the data of the external recording medium provided with one or more data missing portions is input to the terminal of each user, and the data corresponding to the data missing portion is input to the server. a step of requesting the transmission of the data, each encrypted the missing data that function as different for the function associated with each of the user and parameters for each of the missing data at the server to each user as the encryption key A data transmission / reception method is configured by a process of transmitting data to a terminal of each user and a process of decrypting the encrypted missing data and replenishing the data missing portion with a decryption key comprising the function held by each user. It was.
[0006]
Parameters related to the missing data can be common to each user . Its parameters missing data corresponding to the data defect to may be transmitted from the server. Further, these decryption keys may be recorded on a memory card and input at a terminal. It is preferable that the missing data corresponding to the data missing portion is header information to be stored in the external recording medium .
[0007]
In order to construct the data transmission / reception method as a computer system, the data of the external recording medium provided with one or more data missing portions is input to each terminal, and the server stores the missing data corresponding to the data missing portion. Means for requesting transmission, means for encrypting the missing data with a different key corresponding to each terminal in the server, and transmitting the data to each terminal, and the encryption by the decryption key held in each terminal. What is necessary is just to comprise a system by the means which decodes the digitized missing data, and supplements a data missing part.
[0008]
The decryption key may be a function related to a parameter held by each terminal. In addition, the decryption key is different for each terminal and missing data, and can be expressed by a function related to the parameter of the terminal and the parameter of the data missing part. The parameter of the missing data corresponding to the data missing part may be transmitted from the server. Further, these decryption keys may be recorded on a memory card and input at a terminal. It is preferable that the missing data corresponding to the data missing portion is header information to be stored in the external recording medium .
[0009]
Embodiment
Embodiments of the present invention will be described below with reference to the accompanying drawings. As shown in FIG. 1, the server S on the information providing side and the terminals T ₁ ..Tn of a plurality of users U ₁ ..Un are connected via a public line communication network such as the Internet so that data communication is possible. . The server S has a computer and an appropriate database file, and the terminals T ₁ ... Tn are composed of personal computers, for example, and include pointers, displays, printers, IC card readers, image scanners, external recording medium readers, and the like. An output device is provided. Any external recording medium, such as a CD, DVD, or memory card, can be used as long as it has a large capacity and is compact.
[0010]
As shown in FIG. 2, the external recording medium 1 is provided with one or more data missing portions D ₁ . The missing portion Di is preferably a portion corresponding to information necessary for displaying content such as header information. Moreover, you may provide the defect | deletion part Di from the content previously formed using the data compression or the stirring system.
[0011]
Next, a method for transmitting and receiving information using the recording medium 1 will be described with reference to FIGS. For example, in the case of correspondence education, when a person who wants to attend (user Un) applies for attendance, an external recording medium 1 and an IC card 2 in which teaching materials are recorded in advance are delivered by mail or the like. In the first step S ₁ , the user Un reads the external recording medium 1 using the terminal Tn, holds the data on a hard disk or the like, and requests the server S to transmit the missing data CU ₁ . Therefore, the IC card 2 is read by the terminal Tn, and the ID and password are sent to the server S. This IC card stores parameters and decryption key functions described later, and these functions are also read.
[0012]
When the ID and password are transmitted to the server S, the server S encrypts and transmits the data CU ₁ ..CUi respectively corresponding to the missing portion D ₁ ..Di to each user Un. Receive. If the encryption key is KSn, KSn is different for each user Un. And instead of sending the decryption key KSn to each user Un, x is an independent variable,
KSn = fn (x, KUn) (1)
Each user Un owns the parameter KUn and its function fn (x, KUn) or transmits only the parameter KUn and possesses the function fn (x, KUn). These parameters KUn may or may not be common to each user Un, but at least the function fn (x, KUn) is preferably different for each user Un. Furthermore, the decryption key KSn can be made different for each missing data CUi. That is,
KSn = fn (x, Ci, KUn) (2)
Then, a series of parameters C ₁ ... Ci are transmitted from the server S and received by the user Un (step S ₃ ), or each user Un holds in advance. However, at least the function fn (x, Ci, KUn) is assumed to be held by the user Un. The possession method is preferably recorded on the IC card 2, but in addition to this, for example, when applying for a course, the user U ₁ ·· Un is given the formula (1) or (2), respectively, and input to each terminal Tn in advance. You may keep it. The parameters C ₁ ... Ci are preferably common to each user Un.
[0013]
In step S ₄ , a decryption key KSn is created by the terminal Tn based on the above formula (1) or (2), and in step S ₅ , the data CU _1. Part D ₁ ..Di is supplemented with data to complete the teaching material and stored in a hard disk or the like as a database. The server S and the user Un is to take with each other performs communication based on the finished materials in step S _6.
[0014]
If the amount of information of the data CU ₁ .. CUi corresponding to the missing part D ₁ ... Di is expected to be extremely large, all the data is received by the terminal Tn in advance in a sufficiently long time before attendance. It is preferable to decipher and complete the teaching materials. In addition, other memory cards such as a magnetic card can be used instead of the IC card.
[0015]
【The invention's effect】
According to the present invention, as described above, a data missing portion is previously formed in the external recording medium, data corresponding to this missing portion is encrypted with a different key for each user, and transmitted to the user. Since the decryption key is calculated from the function given in advance and the missing data is decrypted, the contents cannot be known even if the external recording medium is copied, and the encryption is decrypted even if the missing data is stolen. Because it is difficult to find the decryption key because the decryption key differs for each user, complete data is protected in a double and triple manner, and a large amount of information that includes know-how such as teaching materials is sent and received. It's the best way to do it.
[0016]
Furthermore, since the decryption key of each user is different, there is an advantage that the user's content accountability becomes clear and a service system for each user can be established.
[Brief description of the drawings]
FIG. 1 is a schematic diagram showing an example of hardware used in the data transmission / reception method of the present invention. FIG. 2 is a plan view showing an example of an external recording medium. FIG. 3 is a block diagram showing data transmission / reception relationships. Showing the program processing steps in the terminal
1 External recording medium 2 IC card C ₁ ..Ci parameter CU ₁ ..CUi missing data D ₁ ..Di missing part KSn decryption key KUn parameter S server S ₁ ..S ₆ processing steps T _1. U ₁・ ・ Un User

Claims (5)

A step of requesting the transmission of the corresponding missing data the data of the external recording medium in which a data loss of more than one place in the data defect to the server by entering the terminal of each user, each user at the server and a process of transmitting the function associated with each of the missing data parameters to each for the user and different from the terminal of each user by encrypting the missing data that function as an encryption key, each user A data transmission / reception method comprising the step of decrypting the encrypted missing data by using the decryption key comprising the function held in the above and replenishing the data missing portion. The data transmission / reception method according to claim 1, wherein the parameter for missing data is common to each user . The data transmission / reception method according to claim 1 or 2 , wherein a parameter for missing data in the data missing part is transmitted from a server. Method of transmitting and receiving data according to any one of claims 1 to 3, decryption key consisting of the function is to be inputted are recorded on the memory card to the user's terminal. Method of transmitting and receiving data according to any one of claims 1 to 4-deficient data corresponding to the missing data unit is a header information to be stored in the external recording medium.

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