JP2001005919A - Device and method for information management in information management system using portable data carrier - Google Patents

Abstract

PROBLEM TO BE SOLVED: To maintain the security of an information management system using a portable data carrier and to make avoidable the constraint of storage capacity in the portable data carrier. SOLUTION: This information managing device is realized by three functions. A 1st means reads a key 122 stored in a portable data carrier 102 in response to a received instruction, performs encipherment 111 of the key into information 131 of a general communication network and stores enciphered received information in an external file 114. A second means reads the key 122 on the basis of a storage instruction, performs decoding 112 of the file 114 and stores the decoded external file as storage information 121 in a data carrier. A 3rd means updates the key 122 in response to decode processing, stores the key and eliminates the file 114.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information management apparatus and an information management method in an information management system using a portable data carrier such as an IC card, and more particularly to a storage capacity limitation of a portable data carrier while ensuring security. The present invention relates to an information management apparatus and an information management method for avoiding the problem.

[0002]

2. Description of the Related Art An information management system using a portable data carrier (hereinafter referred to as a portable data carrier) and comprising a plurality of terminals is known. The system is required to ensure maximum security when storing and reading data to and from the portable data carrier, and to avoid restrictions on the storage capacity of the portable data carrier.

[0003] Due to the limitation of the storage capacity of the portable data carrier, the portable data carrier stores minimum necessary information. In addition, this system is a large-scale system in which security is ensured by online processing and access history to a portable data carrier.

[0004]

When an external file is used in order to avoid the restriction on the storage capacity of a portable data carrier, it is practically difficult to reduce security and guard by an access history. Therefore, it is difficult to achieve both security maintenance and avoiding restrictions on the storage capacity of the portable data carrier. The primary purpose is to maintain the security of the information stored on the portable data carrier,
It is an object of the present invention to provide an information management device which makes it possible to avoid the restriction on the storage capacity of a portable data carrier.

[0005]

In order to achieve the above object, an information management apparatus according to the present invention includes a first means, a second means and a third means. The first means responds to the reception instruction,
The key stored in the portable data carrier is read, the received information of the general communication network is encrypted, and the encrypted received information is stored as an external file. The second means is
The key is read out based on the storage instruction, the external file is decrypted, and the decrypted external file is stored as storage information in the data carrier. The third means updates the key in response to the decryption processing, stores the updated key on the data carrier, and erases the external file.

[0006] With the above configuration, in order to avoid the restriction on the storage capacity of the portable data carrier, the encryption processing is executed by updating each time an external file of the terminal that becomes a security hole is generated. The key update process can prevent the key from being analyzed, and can prevent the storage of information from an unauthorized external file. Therefore, it is possible to avoid the restriction on the storage capacity of the portable data carrier while maintaining the security of the information stored in the portable data carrier.

The difference between the present invention and the prior art is that the security is maintained while using an external file necessary for avoiding the restriction of the storage capacity of the portable data carrier, and the history management is not performed without the history management. The point is to realize the function.

[0008] In another aspect of the information management apparatus of the present invention, the first means is characterized in that an external file is decrypted based on the received general communication network information and a key stored in a portable data carrier. And encrypting the combined information with the stored information stored on the data carrier and storing the encrypted combined information as an external file. Here, the key is updated and stored as the current key in response to generation of the decrypted information. The second means reads the current key, performs a decryption process on the external file, and stores information indicated by a storage instruction to the data carrier from the decrypted external file.
The third means updates the current key in response to the decryption processing, stores the updated current key in the data carrier, deletes information based on the storage instruction from the decrypted external file, and stores the information based on the updated current key. The information other than the information based on the instruction is encrypted, and the encrypted information is stored as an external file.

In the processing for transferring the storage information of the portable data carrier to an external file according to the above-mentioned configuration, the first means includes an external file by combining the processing with the second means (the decoding processing includes verification processing). Falsification and breaking. The second means decrypts the external file encrypted with the key used for decryption, and guarantees the validity of the external file using the verification information included in the external file. The security of the external file is secured by the above two means.

Further, in another aspect of the information management apparatus of the present invention, the first means comprises: storage information to be transferred as an external file from information of a general communication network stored on a portable data carrier; Are read and encrypted, and stored individually as external files forming an external file group.
The second means reads the key and decrypts the external file, and stores information indicated by the storage instruction to the data carrier from the decrypted external file. Third means for updating the key in response to the decryption and storing the key on a data carrier;
The information based on the storage instruction is deleted from the decrypted external file, and information other than the information indicated by the storage instruction is encrypted based on the updated key, and the encrypted information is used as the external file. Store. The fourth means performs decryption based on the key in each file other than the decrypted external file in the external file group, and encrypts each file decrypted based on the updated key. , So as to form an external file group.

[0011] With the above configuration, management of encryption and decryption processing for an external file group is enhanced, and
The overall processing amount is reduced due to the reduction in the frequency of the key update processing.

An information management method in an information management system according to the present invention uses a portable data carrier and various terminals,
A terminal that stores information on a data carrier. When information stored on a data carrier is stored in an external file in the terminal, the information is encrypted with a key generated each time an external file is created and saved as an external file. This is realized by storing the generated key in the portable data carrier and performing decryption and verification using the key stored in the portable data carrier when storing the information in the portable data carrier.

[0013] The information management method further includes storing the stored information in the data carrier in an external file, and writing the information back from the external file to the portable data carrier. Furthermore, new information is added to the information obtained by decrypting and verifying the external file, encryption is performed with a key generated each time the external file is created, and the generated key is stored as an external file, and the generated key is stored in a portable data carrier. Storing the information on the data carrier further includes performing decryption and verification using the key stored on the portable data carrier.

The information management program in the information management system according to the present invention is a terminal for storing information in a data carrier using a portable data carrier and various terminals, and transmitting information stored in the data carrier to an external device in the terminal. When saving to a file, encrypt with the key generated each time an external file is created, save it as an external file, save the generated key on the portable data carrier, and store the information on the portable data carrier A program for performing decryption and verification using a key stored in a portable data carrier is stored in a recording medium.

[0015] The information management program further includes storing the stored information in the data carrier in an external file, and writing back the information from the external file to the portable data carrier. Furthermore, new information is added to the information obtained by decrypting and verifying the external file, encryption is performed with a key generated each time the external file is created, and the generated key is stored as an external file, and the generated key is stored in a portable data carrier. Storing the information on the data carrier further includes performing decryption and verification using the key stored on the portable data carrier.

[0016]

Embodiments of the present invention will be described in detail with reference to the accompanying drawings. As will be described later, the information management apparatus of the present invention includes a means (first means, not shown) for performing an encryption process and a creation process for an external file, a decryption process for information of the external file, and a portable data carrier. (Second means, not shown), means for updating the key and erasing the external file following the decryption processing (third means, not shown), The function is realized by means for performing a file update process (fourth means, not shown).

FIG. 1 is a diagram showing an information management system accommodating an information management device (101) according to a first embodiment of the present invention. The information management system includes a terminal 101 and a portable data carrier 102. FIG. 1 shows only the terminal 101 among a plurality of terminals constituting the information management system. Arrows between the portable data carrier 102 and the terminal 101 indicate bus lines for exchanging information.

The portable data carrier according to the present invention comprises:
A portable data carrier (hereinafter, referred to as a data carrier) such as an IC (Integrated Circuit) card or a magnetic stripe card is shown. The data carrier is inserted into a card insertion slot (read / writer unit, not shown) of the information management device (101, 201, 301) of the present invention, and data exchange is performed.

The terminal 101 comprises an encryption section 111, a decryption section 112, a key update section 113, an external storage section 114, and a terminal control section 115. In the present invention, a hard disk, a magnetic disk, or the like is applied to the external storage unit. The external storage unit 114 according to the present embodiment collectively stores a plurality of external files in one file.

The information to be processed in this system includes original information 131 existing in a wide area communication network such as the Internet or a narrow area communication network such as an in-house network (hereinafter, these are defined as general communication networks), and a terminal. An external file stored in the external storage unit 114 of the portable data carrier 102, storage information stored in the carrier storage unit 121 of the portable data carrier 102, and a key (key information) stored in the key storage unit 122.

FIG. 2 is a flowchart showing an information management method according to the present embodiment. In this figure, terminal 1
No. 01 stores the original information 131 existing in the general communication network in the portable data carrier 102. An operation according to the present embodiment will be described in correspondence with the above-described functions.

First, the processing of the first means is executed.
The data carrier 102 is inserted into a read / write unit (predetermined position) of the terminal 101, and a reception instruction is input by a user via an input unit (not shown) such as a keyboard of the terminal 101. The reception instruction indicates information to be received in the general communication network. Terminal control section 115 controls the following operation in response to the reception instruction.

The encryption section 111 adds verification information to the original information (reception information) received based on the reception instruction. The encryption unit 111 reads a key (key information) from the data carrier 101 (step S101), and encrypts the original information to which the verification information has been added, using the read key information. The encrypted original information (encrypted information) is stored in the external storage unit 114 as an external file (step S10).
2). The external file is information of an encrypted text.

Next, the processing of the second means is executed.
The case where an external file is stored in the data carrier 102 is shown. The data carrier 102 is inserted into the read / writer unit of the terminal 101, and a storage instruction is input by a user via an input unit such as a keyboard of the terminal 101. The storage instruction indicates information to be stored in the data carrier 102 from the external file. The terminal control unit 115 controls the following operation in response to the storage instruction.

The decryption unit 112 reads the key information from the data carrier 102 (step S103), decrypts the external file using the read key information, and decrypts the external file using the verification information. The validity of the external file is verified (step S104). The decoding unit 112
The decrypted and verified external file is transferred to the data carrier 102
Is stored as a storage report in the carrier storage unit 121 (step S105). The storage information 121 is plain text information.

Next, the processing of the third means is executed.
The key updating unit 113 newly updates the key in response to the processing in step S104, and stores the updated key in the key storage unit 122 (step S106). At this time, the external file corresponding to the storage instruction is deleted.

As described above, the external file stored in the external storage unit 114 is updated following the process of updating the key information stored in the carrier storage unit 121. Therefore, the terminal 101
Is replaced with an unauthorized file (falsified file, copy file, old file), the unauthorized file is detected by the decryption processing and the verification processing in the decryption unit 112. Also, the key updating unit 113
With the key update process described above, the conventional access history becomes unnecessary, and only the latest external file is processed. Therefore, the information management system according to the present embodiment can hold the stored information as an external file outside the portable data carrier while maintaining the security of the information stored in the portable data carrier, thereby avoiding the limitation of the storage capacity. it can.

FIG. 3 is a block diagram showing an information management system accommodating the information management device (201) according to the second embodiment of the present invention. The information management system is a terminal 20
1 and a portable data carrier 202. FIG.
In the figure, only the terminal 201 is shown among a plurality of terminals constituting the information management system. Data carrier 20
An arrow between the terminal 2 and the terminal 201 indicates a bus line for exchanging information.

The terminal 201 includes an encryption unit 211, a decryption unit 212, a key update unit 213, an external storage unit 214, and a terminal control unit 215. The information to be processed in this system is the original information 2 existing in the general communication network.
31, the external file stored in the external storage unit 214 of the terminal 201, and the carrier storage unit 2 of the portable data carrier 202.
21 and the key (key information) stored in the key storage unit 222.

In this embodiment, in addition to the received information as the external file, the storage information transferred from the data carrier 202 and the already stored external file are combined. Update the external file in consideration of the difference between the encryption key applied to the external file and the encryption key applied to the received information,
Further, a storing process to the data carrier 202 is executed.

FIG. 4 is a flowchart showing an information management method according to the present embodiment. In the figure, terminal 2
No. 01 stores the original information 231 existing in the general communication network in the portable data carrier 202. An operation according to the present embodiment will be described in correspondence with the above-described functions.

First, the processing of the first means is executed.
The data carrier 202 is inserted into the read / writer unit of the terminal 201, and a reception instruction and a transfer instruction are input by a user via an input unit (not shown) such as a keyboard of the terminal 201. The reception instruction indicates information to be received in the general communication network. The transfer instruction is transmitted from the data carrier 202 to the terminal 20.
The storage information to be transferred to the first external storage unit 214 is shown. The terminal control unit 215 controls the operation described below in response to each instruction.

The encryption unit 211 reads a key (key information) and storage information to be transferred from the carrier storage unit 221 to the external storage unit 214 (step S201). In the present embodiment, the key information is input via the decryption unit 212. The decryption unit 212 performs decryption and verification processing on the external file stored in the external storage unit 214 based on the key information (Step S202).

Next, the key updating device 213 sends a new key (first
Is generated (step S203), and the first key is stored in the key storage unit 222 (step S204). At the same time as step S204, the encryption unit 202 adds the read storage information (step S201) and the decrypted and verified external file to the received original information (reception information) 231 based on the first key. (Step S202) and the information for verification are added to generate combined information, and an encryption process is executed.

The connection information encrypted based on the first key (encryption connection information) is stored in the external storage unit 214 as an external file (step S205). When the stored information is read from the portable data carrier 202 in step S201, the stored information stored in the carrier storage unit 221 is deleted.

Next, the processing by the second means is executed. The case where a part or all of the external file (encrypted combination information) is stored in the data carrier 202 is shown. The data carrier 202 is inserted into the read / writer unit of the terminal 201, and a storage instruction is input by a user via an input unit such as a keyboard of the terminal 201. The storage instruction indicates information to be stored in the data carrier 202 from the external file. The terminal control unit 215 controls the following operation in response to the storage instruction.

The decryption device 212 reads the first key from the key storage 222 (step S206), decrypts the external file based on the first key, and verifies the validity of the external file using the verification information. Verification (Step S2)
07). After the validity is confirmed, the information corresponding to the storage instruction is stored in the carrier storage unit 221 from the decrypted and verified external file (decryption combined information) as storage information (step S208).

Next, the processing of the third means is executed.
First, the first key is updated to the second key by the key updating unit 313 (step S209). At this time, information corresponding to the storage instruction in the external file is deleted. Next, the encryption unit 211 encrypts information other than the information corresponding to the storage instruction from the external file (decryption combined information) decrypted and verified based on the second key, and It is stored in the external storage unit 214 as a file (step S2
10). At the same time as the processing in step S210, the second key is
It is stored in the key storage unit 222 (step S211). Thus, the processing of the third means is completed.

Also, a case will be shown in which, when the process of step S205 is executed, only the storage report stored in the carrier storage unit 221 by the terminal 202 is stored in the external storage unit 214. The data carrier 202 is inserted into the read / writer unit of the terminal 201, and a shift instruction is input by a user via an input unit such as a keyboard of the terminal 201. The transfer instruction indicates storage information to be transferred from the data carrier 202 to the external file. The terminal control unit 215 controls the following operation in response to the transfer instruction.

The encryption unit 211 reads the key information stored in the key storage unit 222 and the storage information to be transferred as an external file (step S201). The decryption unit 212 decrypts and verifies the external file (step S202).

Next, a key (first key) is generated by the key updating unit 213 of the terminal 201 (step S203), and the first
Are stored in the key storage unit 222 (step S20).
4) At the same time, after adding the information obtained by decrypting the above-mentioned external file to the read storage information and the verification information, the encryption unit 211 encrypts the information using the next key information, and stores the external file as an external file. It is stored in the unit 214. The read storage information is deleted from the carrier storage unit 221.

Incidentally, it is also possible to execute the common processing substantially simultaneously in consideration of the efficiency of the processing. For example, in the flowchart shown in FIG.
It is also possible to simultaneously execute the processing from step 3 to step S205 and the processing from step S209 to step S211. In this case, the processes are common in terms of key update processing, encryption and storage processing of an external file (encrypted file), and storage processing of an updated key. This means that the decryption unit 212 and the encryption unit 211 are directly connected in FIG.
The point is that data transfer is performed.

By the above operation, the portable data carrier 20
2, only necessary information is stored in the carrier storage unit 221.
Other information is managed in the external storage unit 214 of the terminal 201. The external file stored in the terminal 201 is
The key information stored in the portable data carrier 202 is updated following an update process. Therefore, when an external file in the external storage unit 214 is replaced with an unauthorized file (a falsified file, a copy file, an old file, or the like), an unauthorized file is detected in the decryption processing and verification in the decryption device 212. Also, the key update unit 213
Since the key information is updated every time, it is possible to process only the latest external file without using the history information. As described above, the information management system according to the present embodiment can hold stored information as an external file outside the portable data carrier while maintaining the security of the information stored in the portable data carrier.

FIG. 5 is a block diagram showing an information management system accommodating the information management device (301) according to the third embodiment of the present invention. As shown in FIG. 5, the information management system includes a terminal 301 and a portable data carrier 302. FIG. 5 shows only the terminal 301 as a plurality of terminals constituting the information management system. Arrows between the data carrier 302 and the terminal 301 indicate bus lines for exchanging information. In the present embodiment, a plurality of external files are individually stored as an external file group instead of one file.

The terminal 301 includes an encryption unit 311, a decryption unit 312, a key update unit 313, an external storage unit 314, a writing unit 316, and a terminal control unit 315. The information to be processed in the present embodiment includes the original information 331 existing in the general communication network and the external storage unit 31 of the terminal 301.
4 and the portable data carrier 30
The storage information stored in the second carrier storage unit 321 and the key (key information) stored in the key storage unit 322.

FIG. 6 is a flowchart showing an information management method according to the present embodiment. In the figure, terminal 3
01 shows a case where the original information 331 existing in the general communication network is stored in the portable data carrier 302. An operation according to the present embodiment will be described in correspondence with the above-described functions.

First, the processing of the first means is executed.
The data carrier 302 is inserted into the read / writer unit of the terminal 301, and a reception instruction is input by a user via an input unit (not shown) such as a keyboard of the terminal 301. The reception instruction indicates information to be received in the general communication network and an instruction to be directly stored in the data carrier 302. Terminal control unit 315
Controls the operations described below in response to each instruction.

The writing section 316 of the terminal 301 receives the original information (reception information) based on the reception instruction (step S3).
01), and stored as storage information in the carrier storage unit 321 of the data carrier 302 (step S302).

Next, a case where the storage information stored in the carrier storage unit 321 is stored as the external file group 314 of the external storage unit 301 will be described. The data carrier 302 is inserted into the read / writer unit of the terminal 301, and a transfer instruction is input by a user via an input unit (not shown) such as a keyboard of the terminal 301. The transfer instruction indicates storage information to be transferred from the data carrier 302 as an external file. The terminal control unit 315 controls the following operation in response to the transfer instruction.

The encryption unit 311 reads the storage information and the key corresponding to the transfer instruction from the data carrier 302 (Step S).
303). The encryption unit 311 performs an encryption process on the read storage information obtained by adding the verification information to the read storage information based on the read key, and stores the information in the external storage unit 314 as an individual external file (step S304). ). The external files individually stored are information of ciphertexts and form a part of the external file group.

Next, the processing by the second means is executed. The case where some external files of the external file group are stored in the carrier storage unit 321 is shown. The data carrier 302 is inserted into the read / writer unit of the terminal 301, and a storage instruction is input by a user via an input unit (not shown) such as a keyboard of the terminal 301. The storage instruction here indicates an external file to be stored in the data carrier 302 in the external file group and its internal information. The terminal control unit 315 controls the following operation in response to the storage instruction.

The decryption unit 312 reads the key from the key storage unit 322 (step S305), and performs decryption and verification processing on the external file corresponding to the stored information using the read key (step S306). The writing unit 316
From the decrypted and verified external file, information corresponding to the storage instruction is stored in the carrier storage unit 321 as storage information (step S307). This storage information is plaintext information.

Next, the processing by the third means is executed. The key updating unit 313 newly updates the key (Step S308). If there is information not stored in the data carrier 302 in the external file corresponding to the storage instruction, the encrypting unit 311 adds verification information to the unstored information, and the verification information is generated based on the updated key. The added unstored information is subjected to an encryption process and stored individually as an external file (step S309). The key updating unit 314 stores the updated key in the key storage unit 322 (Step S310).
The information of the external file corresponding to the storage instruction is deleted.

Next, the operation of the fourth means is executed.
After step S311, an update process is performed on each file in the external file group that does not correspond to the storage instruction.
The decryption unit 312 performs decryption and verification processing based on the key for all of the external files encrypted with the key (the key before update), and generates each decrypted and verified file (step S312). . The encryption unit 311 encrypts each of the decrypted and verified files based on the updated key, and stores each as an external file (step S3).
13). As described above, the entire external file group is updated based on the updated key.

Incidentally, it is also possible to execute the common processing substantially simultaneously in consideration of the efficiency of the processing. For example, in the flowchart shown in FIG.
It is also possible to execute the process 2 and the process of step S307 at the same time. In this case, the processing is common from the viewpoint of the storage processing on the data carrier. This is in FIG. 5 in that the decryption unit 312 and the encryption unit 311 are directly connected, and data transfer is performed.

In the present embodiment, while the same processing as that of the second embodiment is achieved by the above-described processing, the number of external file group management processing increases as compared with the second embodiment, but the key update Frequency can be reduced. As is apparent from the result, the information management system according to the present embodiment can avoid the limitation of the storage capacity of the portable data carrier while maintaining the security of the information stored in the portable data carrier, which is difficult with the conventional technology. Can be realized more easily.

[0057]

According to the information management apparatus and method in the information management system of the present invention, each time an external file is transferred to a portable data carrier, the encryption and decryption keys are updated, and the transfer is performed following this key update process. The deleted external file is deleted. The restriction on the storage capacity of the portable data carrier is avoided while maintaining security. An information management system for performing various services using a portable data carrier such as an electronic ticket service is realized.

[Brief description of the drawings]

FIG. 1 is a block diagram for explaining a first embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation of the first embodiment of the present invention.

FIG. 3 is a block diagram for explaining a second embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation of the second embodiment of the present invention.

FIG. 5 is a block diagram for explaining a third embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of the third embodiment of the present invention.

[Explanation of symbols]

 101, 201, 301: terminals 102, 202, 302: portable data carriers 111, 211, 311: encryption units 112, 212, 312: decryption units 113, 213, 313: key update units 114, 214, 314: External storage unit 115, 215, 315: terminal control unit 121, 221, 321: carrier storage unit 122, 222, 322: key storage unit 131, 231, 331: original information 316: writing unit

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 5B058 KA35 5J104 AA16 AA34 NA02 NA35 NA37 PA07 PA14

Claims (9)

[Claims] 1. A first means for reading a key stored in a portable data carrier, encrypting received general communication network information, and storing the encrypted reception information as an external file; Second means for reading a key, decrypting the external file, and storing the decrypted external file as storage information in the data carrier; updating the key in response to the decryption processing to update the key in the data carrier And a third unit for deleting the external file stored in the storage device. 2. A combination of the received general communication network information, information obtained by decrypting an external file based on a key stored on a portable data carrier, and stored information stored on the data carrier. First means for encrypting the obtained information and storing the encrypted combined information as an external file; and in response to generation of the decryption information, the key is updated to a current key. Second means for performing a decryption process on the external file and storing information indicated by a storage instruction in the data carrier from the decrypted external file; and updating the current key in response to the decryption process. Stored in the data carrier, erase the information based on the storage instruction from the decrypted external file, and encrypt information other than the information based on the storage instruction based on the updated current key, The encrypted information Information management apparatus characterized by comprising a third means for storing as said external file. 3. An external file forming a group of external files by reading and encrypting a key and storage information to be transferred as an external file from information of a general communication network stored in a portable data carrier. A second means for reading out the key, decrypting the external file, and storing information indicated by a storage instruction to the data carrier from the decrypted external file; In response to the decryption, the key is updated and stored in the data carrier, information based on the storage instruction is deleted from the decrypted external file, and the storage instruction is updated based on the updated key. Third means for encrypting information other than the indicated information and storing the encrypted information as the external file; and in the external file group, each file other than the decrypted external file is A fourth step of performing decryption based on the stored key, encrypting each of the decrypted files based on the updated key, and storing the files so as to form the external file group;
And an information management device. 4. A terminal for storing information in a data carrier in an information management method using a portable data carrier and various terminals, wherein when storing the information stored in the data carrier in an external file in the terminal, Encrypted with the key generated each time a file is created and saved as an external file, and the generated key is saved on the portable data carrier, and stored on the portable data carrier when storing information on the portable data carrier. An information management method characterized by performing decryption and verification using a decrypted key. 5. The information management method according to claim 4, wherein the information stored in the portable data carrier is stored in an external file, and the information is written back from the external file to the portable data carrier. 6. Addition of new information to information obtained by decrypting and verifying an external file, encryption with a key generated each time an external file is created, storage as an external file, and transfer of the generated key to a portable data carrier. 5. The information management method according to claim 4, wherein when storing and storing the information in the data carrier, decryption and verification are performed using a key stored in the portable data carrier. 7. A terminal for storing information in a portable data carrier in an information management method using a portable data carrier and various terminals, wherein the information stored in the portable data carrier is stored in an external file in the terminal. In addition, the key is generated each time an external file is created, the key is generated and stored as an external file, the generated key is stored in a portable data carrier, and the portable data carrier is used for storing information in the portable data carrier. A recording medium storing an information management program for performing decryption and verification using a key stored in a storage medium. 8. The information management program according to claim 7, wherein the storage information stored in the portable data carrier is stored in an external file, and the information is written back from the external file to the portable data carrier. recoding media. 9. Addition of new information to information obtained by decrypting and verifying an external file, encryption with a key generated each time an external file is created, storage as an external file, and transfer of the generated key to a portable data carrier. 8. A recording medium storing an information management program according to claim 7, wherein the information management program is stored and decrypted and verified using a key stored in the portable data carrier when storing the information in the data carrier.