JP4299934B2 - Electronic information disclosure certification method and system, and storage medium storing electronic information disclosure certification program - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention relates to a method, a system, a computer program, and a recording medium storing the computer program for proving that electronic information on a network has been disclosed.
[0002]
[Prior art]
Conventionally, there has been a method and a system for authenticating that specific electronic information exists at a specific date and time. Such methods and systems are described, for example, in US Pat. No. 5,136,647, US Reexamination Patent RE 349554, US Pat. No. 5,136,646, US Pat. No. 5,373,561, US Pat. No. 5,781,629. However, the technology of the US patent described above does not prove that specific electronic information has been made public, for example, on the Internet.
[0003]
[Problems to be solved by the invention]
In recent years, technical information has been disclosed on the Internet and the like, and such technical information includes information equivalent to technical information published in the form of magazines and books, etc. Etc. are not comparable to conventional publications. Therefore, researchers are increasingly using the Internet for the purpose of publishing their research results at an early stage. In addition, since the transmission of information is simpler and less expensive than conventional publications, there is a high possibility that more information will be disclosed on the Internet or the like. However, although it was possible to prove that electronic information existed in the prior art, it was not possible to prove that it was published on the Internet or the like.
In such a case, that is, when it cannot be proved that it has been published on the Internet or the like, there is a risk that another person will obtain a patent having the same content as the published technical content. As described above, technical information published on the Internet and the like has substantially the same effect as publications. In Japan, patents are granted for “inventions made available to the public through electronic communication lines”. Legislation that does not give However, since it is difficult to prove the fact that the technical information published on the Internet etc. was published or not tampered with, the reliability as evidence is higher than that of conventional publications. It cannot be denied that it is weak.
Further, various objects may be embedded inline in a document such as HTML (Hyper Text Markup Language) used on the Internet or the like. These objects include still images, moving images, sounds, Java applets (Java is a trademark of Sun Microsystems), as well as browser plug-in software and auxiliary applications. Electronic information published on the Internet or the like is composed of a document by HTML or the like and an embedded object, and information is transmitted to the public by a combination thereof. In addition, there is a document in which a hyperlink is provided in a document such as HTML so that an object including a document in another HTML can be referred to as an external resource.
However, electronic information published on the Internet or the like is configured on the assumption that electronic information is browsed online, and when the electronic information is stored locally, the embedded or referenced object is the electronic information. In many cases, it is not available. This makes it impossible to indicate what information the entire electronic information has been disclosed on the network after it is no longer disclosed on the network.
Therefore, the present invention provides a method, a system, and a method for proving the fact that specific electronic information has been disclosed under a predetermined condition on a network such as the Internet and the online information transmission state of the specific electronic information, and the It is an object to provide a recording medium storing a computer program.
[0004]
[Means for Solving the Problems]
According to the first aspect of the present invention, there is provided an electronic information disclosure certification method for certifying that specific electronic information has been disclosed on a specific computer connected to a network.
In response to the recording request, the service provider computer changes the IP address of the access source to access the specific electronic information stored in the specific computer, and the specific electronic information and the specific electronic information A first step of copying the object if the object is included in the object, and the service provider's computer may store the specific electronic information and the specific electronic stored locally when the object is stored locally. Changing the specific electronic information so that the object can be used from information, and storing the changed specific electronic information together with the copied object in a storage device; A third step of generating attribute information including information on the location of the specific electronic information on the network and the IP address of the access source; The service provider computer copies the specific electronic information and the object, the changed specific electronic information, Generated attribute information To obtain an electronic certificate that uniquely identifies and authenticates 4 And the service provider computer stores the electronic certificate and the attribute information in a storage device corresponding to the changed specific electronic information. 5 Steps. In this way, the electronic information itself that has been made public on the network, and the electronic information that can reproduce the online information transmission state in a pseudo manner, that is, the above-mentioned “changed specific electronic information” Since both certificates can be obtained, it will be possible to prove at a later date what kind of information has been publicly disclosed through the network in the entire electronic information.
The service provider computer stores the copied specific electronic information in the storage device. 6 It is possible to further include steps.
The computer of the service provider provides the certification requester with the electronic certificate, the attribute information, the changed electronic information, and the object stored in the storage device in response to the certification request. 7 It is possible to further include steps.
Furthermore, the service provider computer further includes a seventh step of accessing the second electronic information or the second object referenced from the specific electronic information and copying the second electronic information or the second object. , When the second electronic information and the object and the second electronic information or the second object are stored locally, the object and the second electronic Configuring the information or the second object to make specific electronic information available so that the second object 4 The specific electronic information and object copied and the second electronic information or second object, the changed specific electronic information, and Generated attribute information It is also possible to obtain a digital certificate that uniquely identifies and authenticates the date and time. As a result, the object or the like linked to the specific electronic information can also be a certification target.
The Internet is most easily applied to the network described above. In this case, the electronic information is an electronic document described in a markup language such as HTML (Hyper Text Markup Language) or XML (eXtensible Markup Language). The information on the location of the electronic information on the network is a uniform resource locator (URL), and the access condition can include at least the IP address of the access source. Further, the object included in the electronic information may be a still image, a moving image, a sound, an applet, or data in a format specified by the electronic information.
[0005]
In the electronic information disclosure certification method according to the second aspect of the present invention, the service provider computer changes the IP address of the access source in response to the recording request and stores the specific electronic information stored in the specific computer. A first step of accessing information and, if the specific electronic information and the specific electronic information refer to second electronic information or an object, copying the second electronic information or object; and the service The provider computer can use the second electronic information or object from the specific electronic information stored locally when the specific electronic information and the second electronic information or object are stored locally. The specific electronic information is changed as described above, and the changed second electronic information or object is copied. A second step of storing in a storage device together with the preparative, A third step of generating attribute information including information on the location of the specific electronic information on the network and the IP address of the access source; The computer of the service provider includes the copied specific electronic information and the second electronic information or object, the changed specific electronic information, Generated attribute information To obtain an electronic certificate that uniquely identifies and authenticates 4 And the service provider computer stores the electronic certificate and the attribute information in a storage device corresponding to the changed specific electronic information. 5 Steps. Thereby, for example, the relationship between the electronic information and the linked second electronic information or object can be reproduced later.
According to a third aspect of the present invention, there is provided an electronic information disclosure certification system for certifying that specific electronic information has been disclosed on a specific computer connected to a network, wherein an access source Access means for changing the IP address to access the specific electronic information stored in the specific computer, and copying the specific electronic information and an object included in the specific electronic information; and the specific electronic information When the object is stored locally, the specific electronic information is changed so that the object can be used from the specific electronic information stored locally, and the changed specific electronic information is copied Changing means for storing in a storage device together with the object; Attribute information generating means for generating attribute information including information about the IP address of the access source and the location of the specific electronic information on the network; The copied specific electronic information, the copied object, the changed specific electronic information, Generated attribute information Certificate acquisition means for acquiring a digital certificate for uniquely identifying and authenticating the date and time together with the date and time, and storing the electronic certificate and the attribute information in a storage device corresponding to the changed specific electronic information And means for providing the certification requester with the electronic certificate stored in the storage device, the attribute information, the changed electronic information, and the object.
In the third aspect of the present invention, a configuration further including means for issuing an electronic certificate is possible.
The modification of the first aspect described for the first aspect of the present invention can be applied to the electronic information disclosure certification system according to the third aspect.
[0006]
The electronic information disclosure certification system according to the fourth aspect of the present invention changes the access source IP address to access the specific electronic information stored in the specific computer in response to a recording request, and The electronic information and the specific electronic information refer to the second electronic information or object, means for copying the second electronic information or object, the specific electronic information and the second electronic When the information or object is stored locally, the specific electronic information is changed so that the second electronic information or object can be used from the specific electronic information stored locally, and the changed specific information Means for storing electronic information in a storage device together with the copied second electronic information or object; Means for generating attribute information including information on the IP address of the access source and the location of the specific electronic information on the network; The specific electronic information and the second electronic information or object copied, and the changed specific electronic information; Generated attribute information And a means for acquiring an electronic certificate for uniquely identifying and authenticating the date and time and storing the electronic certificate and the attribute information in a storage device corresponding to the changed specific electronic information, and the storage Means for providing the certification requester with the electronic certificate stored in the apparatus, the attribute information, the changed electronic information, and the second electronic information or object.
Furthermore, the electronic information disclosure certification method according to the first and second aspects of the present invention can be implemented as a program for executing on a computer, such as a floppy (registered trademark) disk, a CD. -Stored in a storage medium or storage device such as a ROM, a magneto-optical disk, a semiconductor memory, or a hard disk.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
First, the outline of the service provided concerning the premise of this invention is demonstrated. For example, the client A records (1) that a Web page (web page) stored in his / her WWW (World Wide Web) server connected to the Internet has been open on the Internet for a considerable period of time. (2) Assume that the service provider B is requested to attach a link to the Web page so that the public can know the presence and location of the Web page.
Upon receiving this request, the service provider B accesses the Web page of the specified URL from an IP address unknown to the client A at an arbitrary timing unknown to the client A, and copies the Web page. Next, the service provider B generates attribute information including the URL of the Web page and the IP (Internet Protocol) address of the access source, uniquely identifies and authenticates the copy of the Web page and the attribute information along with the date and time. Obtain an electronic certificate. Then, the service provider B stores the copy and attribute information of the Web page and the acquired electronic certificate in association with each other.
The service provider B accesses the Web page with the designated URL again at an arbitrary timing that the client A does not know, and copies the Web page. At this time, by changing the IP address of the access source for access, it is possible to additionally obtain proof that the client A's WWW server does not restrict access. Next, the service provider B generates attribute information in the same manner as above, and obtains an electronic certificate that uniquely identifies and authenticates a copy of the Web page and the attribute information together with the date and time. Then, the service provider B stores the copy and attribute information of the Web page and the acquired electronic certificate in association with each other. The service provider B repeats such processing for a considerable period designated by the client A.
In response to the request (2), the service provider B posts a link to the URL of the designated web page on the web page of its own WWW server connected to the Internet so that the general public can access it. . For example, the link may be searchable for each client or for each content field. It should be noted that the fact that the link was posted on the WWW server is also recorded along with the posting period.
[0008]
The requester A can apply to the service provider B for providing the recording contents for the Web page specified in (1) above at the same time as the above request or when necessary. In response to this application, service provider B provides client A with a copy of the saved Web page, attribute information, and electronic certificate. At this time, for example, the above-described data can be written and provided on a CD-R or the like, or can be provided via the Internet. In addition, as a result of (2) above, client A is provided with a record of the fact that the link to the specified Web page has been posted on the WWW server of service provider B and its period, etc. There is also a case.
The client A can use the information provided from the service provider B as proof that the Web page has been published on the Internet for a considerable period of time.
In addition to (1) and (2) described above, the client A records (3) a record that the specified Web page can be searched by the search engine for the general public on the Internet to the service provider B. You can also ask. This is evidence that the public is more easily aware of the existence and location of the Web page. The service provider B performs a search with an appropriate keyword or the like using an arbitrary search engine. When the designated Web page can be searched, the fact that the search has been made, the address and name of the search engine used, the keyword used, the search date and time, etc. are recorded. In some cases, this record is provided as a certificate to the client A in response to a request for providing the record contents.
[0009]
The client A requested to record the Web page stored in his / her WWW server in (1), but (1) 'service to record the Web page stored in the other's WWW server. You can ask provider B. In this case, the service provider B performs the same process as described in (1) above. However, there is no guarantee that the Web page of the other person's WWW server will continue to exist for a considerable period of time designated by client A, and it may disappear or be altered. If the service provider B does not exist, the service provider B records the period when the release was confirmed on the Internet, and in response to the request to provide the record contents of the client A, the service provider B May be provided. In the case of modification, if the processing described above is performed, a modification history remains. The URL of the Web page stored in another person's WWW server may be specified by the client A, or for example, all URLs resulting from a keyword search specified by a specified search engine. Is also possible.
Also, the client A can request (4) the service provider B to record the version transition of the Web page stored in the WWW server of himself or another. For example, the service provider B performs the same processing as (1). However, the service provider B checks whether the content of the Web page accessed last time is different from the content of the Web page accessed this time. If it is different, for example, record that it was different from the previous one.
It is not necessary for service provider B to save a copy of the Web page. For example, the client A may store it. When the service provider B does not store a copy of the Web page, only the attribute information and the electronic certificate are stored for each access in the processes (1) and (1) ′. In the case of (4), if the contents of the web page when accessed last time and the contents of the web page when accessed this time are different, the whole web page is saved only when the difference is saved or is different. By doing so, the version change can be saved.
Further, the client A can specify the recording period, number of times, frequency, etc. in the recording requests of (1) and (1) ′. Service provider B records accordingly.
Furthermore, the services (2) to (4) can be optional, and in particular, the services (2) and (3) can be disclosed to the public by the presence or location of Web pages on other media. Is not necessary.
[0010]
On the other hand, if the service provider B continues this service, it will hold many Web pages with electronic certificates that have been published via the Internet. Using this information, the service provider B can perform (5) a Web page providing service with an electronic certificate. For example, the service provider B builds a database that can perform keyword searches and the like via the Internet, and provides a search service to a third party. Then, in response to a search content provision request from the searcher S, the recorded content is provided via the Internet or on a medium such as a CD-R. In some cases, a summary of a Web page with an electronic certificate is created, and a database is constructed in such a form that search can be screened using the summary.
FIG. 1 shows an outline of an electronic information disclosure certification system for providing the above services. Connected to the network 1 are a server A indicated by 3, a server server B indicated by 5, a server C indicated by 7, a server D indicated by 9, a server E indicated by 11, and a number of computers not shown. The network 1 is the Internet, for example. A server A indicated by 3 is a WWW server, which stores electronic information, for example, a Web page 31 whose URL is http://www.abcd.co.jp, and is made public on the network 1.
A server B indicated by 5 is a server managed by the service provider, accesses the electronic information designated by the client, and obtains a copy, and information and access conditions regarding the location of the electronic information such as a URL, for example. Attribute information generation function 53 for generating attribute information including a certificate, a certificate acquisition function 55 for uniquely identifying and authenticating a copy of electronic information and attribute information together with the date and time, and storing necessary information A storage function 57; and a certificate providing function 59 for providing an electronic certificate or the like stored in response to the request from the client. A storage device 61 is connected to the server B indicated by 5.
A server C indicated by 7 has a time stamp certificate issuing function 71 for issuing a certificate for uniquely specifying and authenticating specific electronic information together with the date and time. The server C indicated by 7 receives a certificate issuance request via the network 1, issues an electronic certificate by the time stamp certificate issuing function 71, and sends the electronic certificate back to the request source.
[0011]
The server D indicated by 9 is a server for adding a function to the server B indicated by 5, and for example, a link 91 to a Web page designated by the client as a WWW server is posted. However, there is a case where such a database of the links 91 is created so that the search can be performed for each content or owner of the linked web page. Further, a database 95 is created using data stored in the storage device 61 connected to the server B indicated by 5, and the server D indicated by 9 has a search function 93 that enables the database 95 to be searched via the network. Sometimes it is. Further, a summary of each electronic information may be created from the data in the storage device 61, and the search function 93 may search the database 97 related to this summary via a network.
A server E indicated by 11 is a search engine for the general public. Since this search engine for the general public is not different from the conventional one, its description is omitted.
Next, services (1) and (1) ′ provided by the present invention will be described as the operation of the system shown in FIG.
For example, the client A designates the Web page of the URL A of the server A indicated by 3 as electronic information to be recorded for a certain period of time, and provides the service (1) or (1) ′. Ask person B. The service provider B performs processing using the server B indicated by 5. The copy acquisition function 51 of the server B indicated by 5 accesses http://www.abcd.co.jp at an arbitrary timing, for example, via the route (A), and copies the Web page 31 via, for example, the route (B). Get. The copy is held in the main memory of the server B indicated by 5, for example. The copy acquisition function 51 stores the access source IP address in the storage device for each access. The copy acquisition function 51 includes a function for determining an access condition. For example, the copy acquisition function 51 determines at which timing and which access source IP address is used during a considerable period designated by the client. Further, when the client designates the frequency, access is scheduled so as to satisfy the designation of the frequency.
The attribute information generation function 53 generates attribute information including the IP address of the access source and the URL specified by the client A. In the attribute information, in addition to the IP address and URL, for example, when the server B indicated by 5 is connected to the network 1 via a proxy server (not shown), the IP address of the proxy server, the access date and time May be included.
[0012]
The certificate acquisition function 55 acquires an electronic certificate for the acquired copy of the Web page 31 and the generated attribute information. More specific processing will be described later. In the system of FIG. 1, the certificate acquisition function 55 receives an electronic certificate issuance request issued via, for example, the route (C) of the network 1 by the time stamp certificate issuance function 71 of the server C indicated by 7. The electronic certificate issued by the time stamp certificate function 71 is received via, for example, the route (D) of the network 1. The time stamp certificate issuing function 71 will be described in detail later.
The storage function 57 stores the copy of the Web page 31 acquired by the copy acquisition function 51, the attribute information generated by the attribute information generation function 53, and the electronic certificate acquired by the certificate acquisition function 55 in the storage device 61. To do. However, saving a copy of the Web page 31 acquired by the copy acquisition function 51 is optional. This is because, for example, the client A sometimes saves himself / herself. In addition, when the content of the Web page 31 copied last time is the same as the content of the Web page 31 accessed this time, the storage function 57 may determine that the copy of the Web page 31 acquired this time is not stored. Good. In addition, the storage function 57 stores data for each client or each designated URL so that the data necessary for the certificate providing function 59 can be easily extracted later.
At the same time as the recording request or at an arbitrary timing, the client A offers to provide the recording contents. At this time, the certificate providing function 59 reads the copy of the Web page 31 to be requested, the attribute information, and the electronic certificate from the storage device 61 accordingly, and in the example of FIG. 1, a storage medium such as the CD-R 63 And provide it to the client A. Note that a copy of the Web page 31, attribute information, and an electronic certificate are stored for each access, but the certificate providing function 59 may provide all of them by storing them in a storage medium such as a CD-R. When there is no change in the copy of the Web page 31, a copy of the Web page 31 at the time of the first access, all the attribute information, and all the electronic certificates may be provided. Further, the certificate providing function 59 creates an access record including the URL, the access source IP address, and the certificate date and time using the attribute information and the electronic certificate, and the access record and the Web page 31 at the time of the first access. It is also possible to provide all attribute information and all electronic certificates as certificates by the service provider B. If the saving function 57 does not save a copy of the Web page 31, the certificate providing function 59 naturally does not provide the client A with a copy of the Web page 31.
[0013]
Next, the service (2) provided by the present invention will be described based on the system shown in FIG. In (2), the client A requests the service provider B to attach a link to the Web page so that the public can know the presence and location of the Web page.
In response to this request, the service provider B posts a link 91 to the Web page 31 stored in the server A indicated by 3 on the server D indicated by 9 connected to the network 1. If the number of requests is small, the URL of the designated web page may be simply posted on the web page stored in the server D indicated by 9. However, if the number of requests is large, a database for links may be constructed so that third parties can search via the network 1 according to the contents of the Web page or the business type of the client. The service provider B records the period during which the link 91 to the web page 31 was posted on his / her web page and the period during which the search was possible in the storage device, and was later requested by the client A or the like. Sometimes the record is provided as a certificate.
Next, the service (3) provided by the present invention will be described based on the system shown in FIG. (3) requests the service provider B to record that the designated Web page can be searched by the server E indicated by 11 which is a search engine for the general public on the network 1.
The service provider B performs a search with an appropriate keyword or the like using the search engine in the server E indicated by 11 through the server B indicated by 5, for example. The fact that the search has been made and the name and address of the server E indicated by 11, the keyword used, the search date and time, etc. are recorded in the storage device. When requested by the client A later, this record is provided as a certificate.
[0014]
Next, the service (4) provided by the present invention will be described based on the system shown in FIG. (4) requests the service provider B to record the version transition of the Web page 31.
The service provider B performs the same process as (1) using the server B indicated by 5. That is, the web page 31 of the server A indicated by 3 is accessed at a predetermined timing, and a copy of the web page 31 is acquired. Next, attribute information including a URL and access conditions is generated, and an electronic certificate is acquired for the attribute information and a copy of the Web page 31. At least attribute information and an electronic certificate are stored in the storage device 61. It is also possible to save a copy of the Web page 31 in a storage device. Next, the Web page 31 of the server A indicated by 3 is accessed at a predetermined timing, the same processing is performed, and an electronic certificate is acquired for the attribute information and a copy of the Web page 31. Then, it is determined whether the content of the Web page 31 when accessed last time, more precisely, the content of the Web page 31 when the most recent change was detected and the content of the Web page 31 when accessed this time are different. This determination may be performed by the copy acquisition function 51 or the storage function 57. If the contents are different, at least in addition to the attribute information and the electronic certificate, the fact that they are different is recorded in the storage device. In some cases, the difference between the content of the Web page 31 when accessed last time and the content of the Web page 31 when accessed this time may be recorded in the storage device. A copy of the entire 31 may be stored in the storage device.
When requested by the client A or the like, the service provider B provides at least attribute information, an electronic certificate, and a record of whether or not there is a change by the certificate providing function 59. The entire web page may be provided for each difference or difference.
[0015]
Next, the service (5) provided by the present invention will be described based on the system shown in FIG. (5) is a Web page providing service with an electronic certificate.
The service provider B provides a search function 93 in the server D indicated by 9, and creates a database 95 using a copy of the Web page 31 with the electronic certificate and attribute information stored in the storage device 61. The database 95 can be searched from the search function 93 by a third party. When a copy of the Web page 31 that a third party desires to use is found, a request for providing recorded contents is submitted to the service provider B via the network 1 or the like. The service provider B uses the certificate providing function 59 to store a copy of the web page 31 requested to be provided to the CD-R 63, the attribute information, and the electronic certificate, and provides the CD-R 63, etc. To do. Data as described above may be transmitted via the network 1.
Further, the service provider B can create a summary from a copy of the Web page 31, construct a summary database 97, and enable a third party to search using the search function 93. After screening the summary database, the third party can confirm a copy of the Web page 31 and issue a request for providing the recorded contents of the necessary electronic information.
The processing flow of the main services (1) and (1) ′ of the present invention is summarized in FIG. When a request from the client A is sent to the service provider B, for example, information relating to the location of electronic information such as a Web page, for example, information relating to the location such as a URL, and a recording condition such as a recording period (step S1). The copy acquisition function 51 determines the access conditions so as to match the recording conditions (step S3), accesses the URL from a predetermined access source IP address at a predetermined timing, and acquires a copy of the Web page. (Step S5). Then, the attribute information generation function 53 generates attribute information including the URL of the Web page and the access source IP address as an access condition (step S7).
Thereafter, the certificate acquisition function 55 acquires an electronic certificate for identifying and authenticating the attribute information and the acquired copy of the Web page together with the date and time from the time stamp certificate issuing function 71 (step S9). The server B indicated by 5 can be configured to include the time stamp certificate issuing function 71. In this case, the certificate obtaining function 55 is replaced with the time stamp certificate issuing function 71.
Then, the storage function 57 stores at least the attribute information and the electronic certificate in the storage device 61 (step S11). As described above, it is optional to save a copy of the Web page in the storage device. This process is repeated until the recording end condition is satisfied (step S13). The condition for ending the recording is, for example, when the recording period specified by the client A has ended, or when the number of recordings specified by the client A has been reached.
[0016]
Next, FIG. 3 shows an example of a processing flow executed in response to a request for providing recorded contents by the client A. Since the record content provision request (step S41) includes the target electronic information, the certificate providing function 59 first identifies the target electronic information (step S43). Then, the certificate providing function 59 reads the copy of the target electronic information, the electronic certificate, and the attribute information from the storage device 61 (Step S45). Note that when the recording request requires recording only once or as a result, the target electronic information disappears after only one access, the data to be read is only one set, but usually multiple times. Therefore, a plurality of copies of electronic information, attribute information, and electronic certificates are read out.
Then, the certificate providing function 59 additionally calculates the publication period (step S47). Since the electronic certificate includes a record of the date and time, if you refer to the electronic certificate acquired at the time of the first access and the electronic certificate acquired at the time of the last access, you can know at least from when to when. Is the publication period. However, this process is arbitrary.
Finally, the certificate providing function 59 ends by storing a copy of the target electronic information, the electronic certificate and attribute information, and the publication period information in a medium such as a CD-R and providing the information (step S49). (Step S51).
Here, the electronic certificate will be briefly described with reference to FIG. In the present invention, the electronic certificate may be issued by any method as long as it issues an electronic certificate that uniquely identifies and authenticates the electronic information along with the date and time. Therefore, the following description is an example, and the electronic certificate may be issued by another method.
Assuming that the electronic information 101 is the subject of the electronic certificate, first, a hash value 103 is calculated for the electronic information 101. The hash function may be any one-way function. For example, the certificate acquisition function 55 performs the calculation up to the hash value. Then, a certificate issuance request including the hash value 103 is sent to the time stamp certificate issuance function 71. The time stamp certificate issuing function 71 performs processing together with other hash values sent in the same manner. For example, as shown in FIG. 4, the process of generating another hash value from two hash values is repeated, and finally one hash value 106 is generated from all the hash values sent. The SHV 107 at the time T is generated using the hash value 106 and the SHV (Super Hash Value) 105 at the time T-1 (T is an integer). The SHV 107 and the hash value 103 generated at the time T, the time information at the time T, and the document ID form the electronic certificate 109. This electronic certificate 109 is transmitted to the sender of the hash value 103, and the electronic information 101 and the electronic certificate 109 can be paired to uniquely identify and authenticate the electronic information 101 together with the date and time.
[0017]
When the Web page is the electronic information shown in FIG. 4, the HTML document corresponds to the electronic information. However, the content of the Web page only needs to be text, but an image file such as a GIF file is embedded in the normal Web page. For example, as shown in FIG. 5, when the web page 31 of the server A indicated by 3 is viewed with a browser of a client computer (not shown) connected to the network 1, objects 201 and 203 such as still images are embedded inline. Is displayed like a Web page 200. Embedded in a Web page is not only a still image, but also a moving image, sound, a file in a format that requires a browser plug-in, etc. Java (trademark of Sun Microsystems) ) Applet. In such a case, the contents of the object embedded in the Web page are also included in the information published on the network.
Further, for example, in FIG. 5, which is an external resource, the Web page 200 includes links 205 to 209 to other Web pages or objects. Although the linked Web page or object cannot be said to be the content published by the URL of the Web page, the user of the network 1 can easily obtain the linked electronic information. Therefore, it can be said that the electronic information can be used by the public. In addition, the web pages or objects ahead of the links 205 to 209 are often related to the web page 200, and the person who created the HTML document of the web page 200 depends on the web page 200 and the linked web page or object. In some cases, it is intended to disclose integrated information. Therefore, there arises a problem of whether or not to make this linked Web page or object a target for acquiring an electronic certificate.
In addition, for example, the HTML document and the objects 201 and 203 of the Web page 200 shown in FIG. 5 are stored locally as files on the server B indicated by 5, for example, and the locally stored HTML document is viewed with a browser. Then, as shown in FIG. 6, only the frames 201a and 203a of the objects 201 and 203 are displayed on the Web page 200a. In some cases, marks 201b and 203b indicating that they have not been read are displayed in the frame. Furthermore, even if the links 205 to 209 are selected with a pointer, the linked Web page or object cannot be viewed.
[0018]
This is because, for example, the following HTML description is included in the HTML document of the Web page 200. Table 1 shows a case where an object is embedded inline. Table 2 shows a case where an external resource is used in the link.
[Table 1]
<IMG SRC = "/ image / image01.gif">
<OBJECT DATA = "/ video / video.avi" TYPE = "video / avi"></OBJECT>
<APPLET CODE = "/ applet / animator.class" WIDTH = 100 HEIGHT = 100></APPLET>
[Table 2]
<A HREF="/image/image02.gif"> 1. image </A>
<A HREF="http://www.xyza.co.jp/home.html> 2. Web page </A>
For example, the first line of Table 1 means that there is a directory called “image” under the directory where the HTML document of the Web page 200 exists, and that the GIF file “image01.gif” is displayed. Naturally, when the HTML document of the Web page 200 is stored locally on the server B indicated by 5, it is not guaranteed that the directory “image” exists under the directory in which the HTML document is stored, and within that, It is not guaranteed that image01.gif will be saved.
The second line of Table 1 has a directory called video under the directory where the HTML document of the Web page 200 exists, and displays a moving image file called video.avi of video / avi in the MIME format. It means that. Naturally, when the HTML document is saved in the server B indicated by 5, it is not guaranteed that the directory called video exists under the directory where the HTML document is saved, and video.avi is saved therein. There is no guarantee that it will be done.
The third line of Table 1 has a directory called applet under the directory where the HTML document of the Web page 200 exists, the Java applet animator.class is executed, and the predetermined display is in the frame 100 × 100. It means that it will be made. As above, if the HTML document is stored in the server B indicated by 5, it is not guaranteed that the directory applet exists under the directory where the HTML document is stored, and applet. There is no guarantee that the class will be saved.
[0019]
The first line in Table 2 means that there is a directory called “image” under the directory where the HTML document of the Web page 200 exists, and a link is attached to the GIF file “image02.gif”. Since only the link is pasted and the contents of this file are not displayed when displaying the HTML document, the contents of the file are not automatically sent via the network 1. Even if this file is stored locally on the server B indicated by 5, it is not guaranteed that there is a directory called image under the directory where the HTML document is saved, and image02.gif may be saved in that directory. Not guaranteed.
The second line in Table 2 means that a link is attached to a Web page with a URL http://www.xyz.co.jp/home.html different from the server storing the HTML document of the Web page 200. is doing. Since the link is only pasted and the content of this file is not displayed when the HTML document of the Web page 200 is displayed, the HTML document of the linked Web page is automatically sent via the network 1. It is not a thing. Even if this HTML document is stored locally on the server B indicated by 5, the storage destination is not this URL http://www.xyz.co.jp/home.html.
As described above, when the HTML document of the Web page 200 is stored locally on the server B indicated by 5, for example, even if the content is checked with a browser or the like, the inline embedded object or the content of the link destination is displayed. I can't see it. In this case, even if the HTML document is stored, it is impossible to accurately grasp the contents that have been disclosed later on the network 1.
Therefore, in the present invention, one copy of the HTML document of the Web page 200 is saved as it is for saving the original, and is changed so that the contents of the entire Web page can be grasped when another copy is viewed later.
For example, in the case of Table 1 and Table 2, the HTML document of the Web page 200 is changed as follows.
[Table 3]
<IMG SRC = "image01.gif">
<OBJECT DATA = "video.avi" TYPE = "video / avi"></OBJECT>
<APPLET CODE = "animator.class" WIDTH = 100 HEIGHT = 100></APPLET>
[Table 4]
<A HREF="/reference/image02.gif"> 1. image </A>
<A HREF="/reference/home.html> 2. Web page </A>
[0020]
Table 3 shows that objects embedded inline are stored in the same directory as the modified HTML document. It is administratively easier to store the attribute information, electronic certificate, HTML document of the Web page 200, and the modified HTML document obtained and generated in one access together with these objects under the same directory. Because. However, this is an example, and as a rule for storing data in the storage device 61 connected to the server B indicated by 5, a directory for storing objects embedded inline is separately created, and the directory is stored in the directory. In some cases, the rule of saving is adopted.
Table 4 shows that an HTML document of an object referred to as an external resource or another Web page is saved in a directory called “reference” under the directory in which the changed HTML document is stored. Thus, in the case of an HTML document of an object or other Web page that is referred to as an external resource instead of being inline, there is a case where these are not acquired, so a separate directory is created and stored therein. However, this is only an example, and as a rule for storing data in the storage device 61 connected to the server B indicated by 5, an object referred to as an external resource or an HTML document of another Web page is also the original It is also possible to adopt a rule of saving in the same directory as the HTML document and the changed HTML document.
In any case, when a Web page includes an object inline, and when referring to an object or another Web page as an external resource, the HTML document file of the Web page 200 as an original and an inline embedded or external resource The object or the HTML document file referred to as is stored as it is, and a modified HTML document is generated and stored for viewing. Then, electronic certificates are acquired for these files and attribute information.
Therefore, the configuration of the server B indicated by 5 shown in FIG. 1 is changed to a server B such as 5 ′ shown in FIG. In other words, the copy acquisition function 151 acquires objects inline embedded and objects referenced as external resources or other electronic information in addition to the designated electronic information. Then, as described above, the copy transformation function 153 changes the reading source of the embedded object, the reference destination object, or other electronic information. Then, the attribute information generation function 155 generates attribute information for these electronic information and objects. At this time, if a copy of the reference destination electronic information or object is acquired, the original reference destination may be included in the attribute information. In some cases, the file includes information indicating what kind of file copy is the subject of the digital certificate issuance.
Then, the certificate acquisition function 157 acquires an electronic certificate for the certificate issuance target information from the time stamp certificate issuance function 71. The storage function 159 stores the certificate issuance target file in the storage device 61 ′ so as to correspond. The storage device 61 ′ stores a copy of electronic information, a modified version of this copy, an electronic certificate, and an object (assuming that it is embedded inline here). The certificate providing function 161 reads the information stored in the storage device 61 ′ in response to the recording content provision request, and creates, for example, a CD-R 63 ′. Here, since the deformed copy and the object are included in the CD-R 63 ′, it is possible to reproduce the same state as when the certification target electronic information was released online. Note that it is arbitrary whether to save a copy of the electronic information before the transformation and whether to provide a copy of the electronic information before the transformation in response to the recording content provision request.
[0021]
Next, a processing procedure performed in response to the recording request will be described with reference to FIG. When a request for recording specifying information (for example, URL) and recording conditions (for example, recording period) regarding the location of the electronic information to be recorded (for example, Web page) and the recording condition (for example, recording period) is issued from the client A (step S61) The copy acquisition function 151 determines the access conditions so as to match the recording conditions (step S63), and accesses the URL from a predetermined access source IP address at a predetermined timing to acquire a copy of the Web page. (Step S65). The copy acquisition process will be described in detail later. The recording request may include, for example, an instruction to copy not only a specified URL but also a link included in the Web page of the URL, for example, up to three levels below. The copy acquisition function 151 copies the linked Web page or object according to this instruction.
Next, the copy transformation function 153 determines whether the copied web page includes an object or a link (step S67). If any of these are included, the copy transformation function 153 may display the inline embedded object in the locally stored copy of the Web page, for example as described above, When the linked link is selected, a copy of the HTML document of the Web page is transformed so that the content of the linked Web page or object is displayed (step S69). On the other hand, if neither a link nor an object is included in the Web page, the process proceeds to (Step S71).
Then, the attribute information generation function 155 generates attribute information including the URL of the Web page and the access source IP address as the access condition (step S71). Next, the certificate acquisition function 157, when there is a copy of the Web page, attribute information, and an inlined object or link, a copy of the HTML document of the modified Web page and an object embedded inline The electronic certificate is acquired from the time stamp certificate issuing function 71 for the copy of the HTML document and the copy of the HTML document or object of the Web page referred to as the external resource (step S73). For example, the storage function 159 stores all the information uniquely identified and authenticated together with the date and time by the electronic certificate in the storage device 61 ′ (step S75). Note that it is optional to save a copy of the HTML document of the Web page in the storage device. This process is repeated until the recording end condition is satisfied (step S77). The condition for ending the recording is, for example, when the recording period specified by the client A has ended, or when the number of recordings specified by the client A has been reached.
[0022]
The copy acquisition process described with reference to FIG. 8 will be described in more detail with reference to FIG. First, a copy of the HTML document of the designated access destination Web page by the client A is acquired (step S93). Then, a copy of the HTML document of the designated access destination Web page is analyzed to check whether an inline embedded object is included (step S95). If an object is included, a copy of the object is also acquired (step S97). On the other hand, if no object is included, the process proceeds to step S99.
Next, it is determined whether there is a link to the Web page or object (step S99). If it exists, a copy of the HTML document or object of the linked Web page is acquired (step S101). On the other hand, if it does not exist, the process ends. In FIG. 9, the copy acquisition range is up to the Web page or object one level below the designated access destination Web page. However, if the Web page or object in the hierarchy below this is the copy acquisition range, The reference destination Web page is regarded as the designated access destination in step S93, and the process of FIG. 9 is performed. At this time, if the link destination below a certain hierarchy is not to be acquired, the process may be terminated without performing steps S99 and S101.
An electronic certificate is acquired for the information acquired and generated in this manner. When acquiring an electronic certificate as described in FIG. 4, the hash value to be generated first is calculated. The following modes can be considered. As shown in FIG. 10, when an object is embedded inline and an external resource is not referenced, an HTML document file of an access destination Web page and an object file (in some cases, a plurality of objects are included). In FIG. 10, two objects, object 1 and object 2, are shown.), A file of attribute information, and a file of a changed HTML document may be combined to generate one hash value. . Thereby, one electronic certificate is acquired.
As shown in FIG. 11, when an object is embedded inline and an external resource is referenced, an HTML document file of the access destination Web page, an object file, an attribute information file, It is also conceivable to generate one hash value for the changed HTML document file and the referenced HTML document or object file. Thereby, one electronic certificate is acquired.
Further, as shown in FIG. 12, when an object is embedded inline and an external resource is referenced, an HTML document file of an access destination Web page, an object file, an attribute information file, A hash value is also generated for the HTML document file that has been changed, and the HTML document or object file of the reference destination Web page and the attribute information for the HTML document of the reference destination Web page A case where the second hash value is generated is also conceivable. In this way, since an independent electronic certificate is issued for the HTML document of the reference Web page, it can be proved that it has been separately published on the network.
In the above description, both the object embedded inline and the Web page or the object referred to as the external resource are acquired. Further, there is a possibility that a lower layer exists as a reference destination for a Web page that is referred to as an external resource. If the client A does not give any instruction, for example, it is possible to follow the principle rule of acquiring up to one level below. Furthermore, an object may be embedded inline in the reference destination web page, and in that case, the object may be handled as being included in the reference destination web page.
[0023]
FIG. 13 shows a process corresponding to the recording content provision request. First, the certificate providing function 161 identifies the certification target electronic information from the request for providing the recorded contents of the client A (step S81). Then, a copy of the target electronic information, an electronic certificate, attribute information, an inline embedded object, a reference object or electronic information, and a modified copy of the target electronic information are stored from the storage device 61 ′. The data is read out and provided by the CD-R 63 ′ (step S85). The processing shown in FIG. 13 is performed in the same manner for the recording content provision request in the service (5) described above.
The content described above is an example, and various modifications are possible. For example, although six functions included in the server B indicated by 5 ′ are illustrated in FIG. 7 so as to be included in one server B indicated by 5 ′, the functions may be divided into a plurality of servers. It is. Similarly, in the server D indicated by 9, a link to the requested Web page is posted and a search function is provided. However, it is also possible to implement these on separate servers. The public search engine connected to the network 1 is not limited to one. Moreover, it is not limited to http, but it can respond also to ftp. The function of the server C indicated by 7 can be included in the function of the server B indicated by 5. The entity that performs the service by the server C indicated by 7 and the entity that provides the service by the server B indicated by 5 ′ may be different or the same. The network 1 is not limited to the Internet, but can be expanded to other networks that permit non-exclusive access and networks that are non-exclusively handled by those who wish to use the network. Although the medium for providing recorded contents is a CD-R, this is also an example, and another medium such as a CD-ROM or a DVD may be used.
1 is merely an example, and one functional block can be divided into a plurality of functional blocks, or a plurality of functional blocks can be combined into one functional block. The apparatus shown in FIGS. 1 and 7 can be configured by a combination of a program that realizes the functions of the functional blocks shown in FIGS. 1 and 7 and a computer, or part or all of the apparatus can be implemented by a dedicated electronic circuit or the like. Is also possible.
[0024]
【The invention's effect】
INDUSTRIAL APPLICABILITY According to the present invention, a method, system, computer program, and computer for proving that electronic information is disclosed under a predetermined condition on a network such as the Internet and the online information transmission state of the electronic information・ We were able to provide a recording medium that stored the program.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an outline of a system in the present invention.
FIG. 2 is a flowchart illustrating an example of processing performed in response to an electronic information recording request.
FIG. 3 is a flowchart illustrating an example of processing performed in response to a recording content provision request.
FIG. 4 is a schematic diagram showing an example of an electronic certificate issuance process for specifying and authenticating electronic information together with date and time.
FIG. 5 is an example of a display screen when a web page is browsed online.
FIG. 6 is an example of a display screen when a web page is browsed offline.
7 is a functional block diagram in the case where the server B (5) in FIG. 1 is changed to a server B (5 ′). FIG.
FIG. 8 is a flowchart illustrating an example of processing performed in response to an electronic information recording request.
FIG. 9 is a detailed flowchart of the copy acquisition step of FIG. 8;
FIG. 10 is a schematic diagram illustrating an example of hash value calculation.
FIG. 11 is a schematic diagram illustrating an example of hash value calculation.
FIG. 12 is a schematic diagram illustrating an example of hash value calculation.
FIG. 13 is a flowchart illustrating an example of processing performed in response to a recording content provision request.
[Explanation of symbols]
1: Network
3: Server A
5: Server B 5 ': Server B
7: Server C
9: Server D
11: Server E
31: Web page
51: Copy acquisition function
53: Attribute information generation function
55: Certificate acquisition function
57: Save function
59: Certificate providing function
61: Storage device 61 ': Storage device
63: CD-R 63 ': CD-R
71: Time stamp certificate issuance function
91: Link
93: Search function
97: Summary database
151: Copy acquisition function
153: Copy transformation function
157: Certificate acquisition function
159: Save function
161: Certificate provision function

Claims (14)

An electronic information disclosure certification method for proving that specific electronic information has been disclosed on a specific computer connected to a network,
In response to the recording request, the service provider computer changes the IP address of the access source to access the specific electronic information stored in the specific computer, and the specific electronic information and the specific electronic information A first step of copying the object if the object includes
The computer of the service provider changes the specific electronic information so that the object can be used from the specific electronic information stored locally when the specific electronic information and the object are stored locally. A second step of storing the changed specific electronic information together with the copied object in a storage device;
A third step of generating attribute information including information on the location of the specific electronic information on the network and the IP address of the access source;
The service provider computer uniquely identifies and authenticates the copied specific electronic information and the object, the changed specific electronic information, and the generated attribute information together with a date and time. A fourth step of obtaining
The service provider's computer, a fifth step of storing in response to the changed the specific electronic information, the electronic certificate and the attribute information in the storage device,
An electronic information disclosure certification method comprising: 2. The electronic information disclosure certification method according to claim 1, wherein the service provider computer further includes a sixth step of storing the copied specific electronic information in a storage device. The service provider computer further includes a seventh step of providing the certification requester with the electronic certificate, the attribute information, the changed electronic information, and the object stored in the storage device. The electronic information disclosure certifying method according to claim 1, wherein: The service provider computer further includes an eighth step of accessing the second electronic information or the second object referenced from the specific electronic information and copying the second electronic information or the second object. Including
The second step includes
When the specific electronic information and the object and the second electronic information or the second object are stored locally, the specific electronic information and the second electronic information or the second electronic information Changing the specific electronic information to make a second object available;
The fourth step includes
Uniquely specifying the copied electronic information and the object and the second electronic information or the second object, the changed specific electronic information, and the generated attribute information together with the date and time; 2. The electronic information disclosure certifying method according to claim 1, wherein the electronic certificate is a step of obtaining an electronic certificate to be authenticated. The network is the Internet;
The electronic information is a document written in markup language.
Information regarding the location of the electronic information on the network is a uniform resource locator;
2. The electronic information disclosure certification method according to claim 1, wherein the object included in the electronic information is a still image, a moving image, a sound, an applet, or data in a format specified by the electronic information. An electronic information disclosure certification method for proving that specific electronic information has been disclosed on a specific computer connected to a network,
In response to the recording request, the service provider computer changes the IP address of the access source to access the specific electronic information stored in the specific computer, and the specific electronic information and the specific electronic information A first step of copying the second electronic information or object if the reference refers to the second electronic information or object;
The computer of the service provider uses the second electronic information or object from the specific electronic information stored locally when the specific electronic information and the second electronic information or object are stored locally. A second step of changing the specific electronic information as possible and storing the changed specific electronic information in a storage device together with the copied second electronic information or object;
A third step of generating attribute information including information on the location of the specific electronic information on the network and the IP address of the access source;
The computer of the service provider uniquely specifies the copied specific electronic information and the second electronic information or object, the changed specific electronic information, and the generated attribute information together with date and time. And a fourth step of obtaining an electronic certificate for authentication;
The service provider's computer, a fifth step of storing in response to the changed the specific electronic information, the electronic certificate and the attribute information in the storage device,
An electronic information disclosure certification method comprising: An electronic information disclosure certification system for proving that specific electronic information has been disclosed on a specific computer connected to a network,
In response to the recording request, the IP address of the access source is changed to access the specific electronic information stored in the specific computer, and the specific electronic information and the object included in the specific electronic information are copied. Access means;
When the specific electronic information and the object are stored locally, the specific electronic information is changed so that the object can be used from the specific electronic information stored locally. Changing means for storing information in a storage device together with the copied object;
Attribute information generating means for generating attribute information including information about the IP address of the access source and the location of the specific electronic information on the network;
Obtaining an electronic certificate for uniquely identifying and authenticating the copied specific electronic information, the copied object, the changed specific electronic information, and the generated attribute information together with a date and time; Corresponding to the changed specific electronic information, electronic certificate acquisition means for storing the electronic certificate and the attribute information in a storage device;
Means for providing the certificate requester with the electronic certificate stored in the storage device, the attribute information, the changed electronic information, and the object;
An electronic information disclosure certification system.   8. The electronic information disclosure certification system according to claim 7, wherein the access means stores the copied specific electronic information in a storage device.   8. The electronic information disclosure certification system according to claim 7, further comprising means for issuing the electronic certificate. The access means accesses the second electronic information or the second object referenced from the specific electronic information, and copies the second electronic information or the second object;
When the changing means stores the specific electronic information and the object and the second electronic information or the second object locally, the object and the second electronic information are stored from the specific electronic information stored locally. Changing the specific electronic information so that the electronic information or the second object can be used,
The electronic certificate acquisition means includes the copied specific electronic information and the object, the second electronic information or the second object, the changed specific electronic information, and the generated attribute information . 8. The electronic information disclosure certifying system according to claim 7, wherein an electronic certificate that uniquely identifies and authenticates the certificate with date and time is acquired. The network is the Internet, and the electronic information is a document written in markup language;
Information regarding the location of the electronic information on the network is a uniform resource locator;
8. The electronic information disclosure certification system according to claim 7, wherein the object included in the electronic information is a still image, a moving image, a sound, an applet, or data in a format specified by the electronic information. An electronic information disclosure certification system for proving that specific electronic information has been disclosed on a specific computer connected to a network,
In response to the recording request, the access source IP address is changed to access the specific electronic information stored in the specific computer, and the specific electronic information and the specific electronic information are the second electronic information or Means for copying the second electronic information or object if referring to the object;
When the specific electronic information and the second electronic information or object are stored locally, the specific electronic information is used so that the second electronic information or object can be used from the specific electronic information stored locally. Means for changing information and storing the changed specific electronic information in a storage device together with the copied second electronic information or object;
Means for generating attribute information including information on the IP address of the access source and the location of the specific electronic information on the network;
Obtain an electronic certificate that uniquely identifies and authenticates the copied specific electronic information and the second electronic information or object, the changed specific electronic information, and the generated attribute information together with the date and time And means for storing the electronic certificate and the attribute information in a storage device in response to the changed specific electronic information,
Means for providing the certificate requester with the electronic certificate stored in the storage device, the attribute information, the changed electronic information, and the second electronic information or object;
An electronic information disclosure certification system. A storage medium storing a program for proving that specific electronic information is disclosed on a specific computer connected to a network,
To a computer other than the specific computer,
In response to the recording request, the IP address of the access source is changed to access the specific electronic information stored in the specific computer, and the specific electronic information and the object included in the specific electronic information are copied. The first step;
When the specific electronic information and the object are stored locally, the specific electronic information is changed so that the object can be used from the specific electronic information stored locally. A second step of storing information in a storage device together with the copied object;
A third step of generating attribute information including information on the IP address of the access source and the location of the specific electronic information on the network;
A first electronic certificate that uniquely identifies and authenticates the copied specific electronic information, the copied object, the changed specific electronic information, and the generated attribute information together with a date and time is acquired. 4 steps,
A fifth step of storing the electronic certificate and the attribute information in a storage device corresponding to the changed specific electronic information;
The storage medium which stored the program for performing. A storage medium storing a program for proving that specific electronic information is disclosed on a specific computer connected to a network,
To a computer other than the specific computer,
In response to the recording request, the access source IP address is changed to access the specific electronic information stored in the specific computer, and the specific electronic information and the specific electronic information are the second electronic information or A first step of copying the second electronic information or object if referring to the object;
When the specific electronic information and the second electronic information or object are stored locally, the specific electronic information is used so that the second electronic information or object can be used from the specific electronic information stored locally. A second step of changing information and storing the changed specific electronic information in a storage device together with the copied second electronic information or object;
A third step of generating attribute information including information on the IP address of the access source and the location of the specific electronic information on the network;
Obtain an electronic certificate that uniquely identifies and authenticates the copied specific electronic information and the second electronic information or object, the changed specific electronic information, and the generated attribute information together with the date and time And a fourth step
A fifth step of storing the electronic certificate and the attribute information in a storage device corresponding to the changed specific electronic information;
The storage medium which stored the program for performing.

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