JP2003114821A - Information exchange method and system for network connecting equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the conventional problem in PtoP which requires the connection of two hosts for performing information exchange to a network that information exchange cannot be regularly performed because the host for holding information is not connected to the network by cut of power supply at network retrieval, and providable information cannot be acquired in spite of is presence in the host. SOLUTION: Each of the host 1 connected to the network every necessity and the information exchange host 1 regularly connected to the network comprises information exchange means and synchronizing means for mutually matching the folder contents of the host 1 and the information exchange host. The non-disclosed information in an information storage means and the information in the synchronizing means and information exchange means are encrypted, and at information exchange with a counter host 3, encryption and electronic signature based on public key method are performed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method of exchanging information between devices connected to a network.

[0002]

2. Description of the Related Art Conventionally, "peer-to-peer (PtoP)" is a technology for exchanging information between devices connected to a network.
Is known (Reference "Short understanding course Internet application technology-Final, PtoP and agents that bring new services; Takashi Sanzen, Nikkei Communication 2001.3.")
. In PtoP, users open their own files on a network via an information exchange device (hereinafter referred to as a host) equipped with file exchange software. If there is a file you want to obtain, search the network,
When it finds the host that holds the file you want to obtain, it connects the local host directly to the other host and acquires the file.

PtoP includes information exchange between unspecified hosts and information exchange among members. There is also one that encrypts and exchanges information.

[0004]

It is desirable that the host that provides information is always connected to the network. However, from the viewpoint of power saving and disaster prevention, the host may not be turned on for 24 hours, such as powering off at night or powering off during absence. As a result, when the network is searched, the host that holds the information to be obtained is powered off, so it is not possible to exchange information at all times, and even if the host has information that can be provided, that information cannot be obtained. There was a problem.

The object of the present invention is to connect an information exchange host to the network at all times as a proxy for the own host, separately from the own host to which a network connection is made every time it is necessary, to provide a folder of the own host and a folder of the information exchange host. By synchronizing with each other, it is possible to always exchange information without constantly connecting the host to the network.

[0006]

In the information exchange method of the present invention, an information exchange host that is always connected to the network is provided separately from the own host that is connected to the network whenever necessary, and the own host and the information exchange host are connected to each other. In each of the above, a public information storage unit that allows information retrieval from the partner host, a private information storage unit that prohibits information detection from the partner host, and has at least acquisition information storage unit that stores new acquisition information, The information exchange means having mutual information retrieval, information request, and information communication functions between the other host and the own host or the information exchange host, and the information acquired by the information exchange host triggered by the network connection of the own host The information in the storage means is compared with the information in the acquired information storage means of the local host, and information not existing in the local host is copied from the information exchange host to the local host. The first synchronization function, the public information storage means of the own host and the public information storage means of the information exchange host, and the private information storage means of the own host excluding the acquired information storage means and the private information of the information exchange host The information stored in each of the storage means is compared, and the information of the own host is copied to the information exchange host so that the information stored in the information exchange host matches the information stored in the own host, and the mismatch information is sent from the information exchange host. A synchronizing means having a second synchronizing function for deleting is provided in each of the information exchanging means of the own host and the information exchanging means of the information exchanging host, and the information exchanging host exchanges information between the own host and the other host. By relaying
The above problems are solved.

In the information exchanging method of the present invention, the information exchanging means has means for encrypting and retaining all the information in the secret information storing means, and responding to the information acquisition request from the partner host. An authentication process of the partner host, an information provision condition confirmation process, a decryption process of the encrypted information, and a re-encryption processor based on the public key of the partner host are provided.

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram of a system implementing the information exchange method of the present invention. The host 1, the exchange host 2, and the partner host 3 are connected to the network 4.
The own host 1 is provided with a file exchange software 11, an encryption software 12, and an exchange folder 13 for occasional connection to the network whenever necessary. Exchange folder 1
3 is divided into a reservation acquisition condition folder 131, an acquisition file folder 141, a provided file folder 151, and a file list folder 161. The file list folder 161 is a file list 16 that can be provided to the other host.
It is a public folder that stores 2 and allows information retrieval from the partner host 3. Folders other than the file list folder 161 in the exchange folder 13 are private folders that prohibit information detection from the partner host 3. The reservation acquisition condition folder 131 has reservation acquisition conditions 132, and the acquisition file folder 141 has acquisition files. The provided file body 152 is stored in the provided file folder 142 and the provided file folder 151, respectively. When the newly provided file 17 is added by the host 1, the file name and file attributes (type, size, provided condition, etc.) of the newly provided file 17 are added to the file list 162, and the file body of the newly provided file 17 is After encrypting with the encryption software 12, it is stored in the provided file folder 151.

The exchange host 2 is always connected to the network for 24 hours and, like the host 1, has file exchange software 21, encryption software 22 and exchange folder 23. The exchange folder 23 includes a reservation acquisition condition folder 231, an acquisition file folder 241, a provided file folder 251, and a file list folder 26.
Divided into 1. The file list folder 261 is a public folder that stores a file list 262 that can be provided to the partner host and allows information search from the partner host. File list folder 2 of exchange folder 23
Folders other than 61 are private folders that prohibit information detection from the other host, and the reservation acquisition condition folder 231.
Reservation acquisition condition 232, acquisition file folder 241
Includes an acquisition file 242 and a provided file folder 251.
Each of the provided file bodies 252 is stored in.

The partner host 3 is a partner host for exchanging information, and like the hosts 1 and 2, file exchange software 31, encryption software 32 and exchange folder 33.
Is provided. The exchange folder 33 includes a reservation acquisition condition folder 331, an acquisition file folder 341, a provided file folder 351, and a file list folder 361.
It is divided into The file list folder 361 is a public folder that stores a file list 362 that can be provided to the partner host and allows information search from the partner host.
File list folder 361 of the exchange folder 33
Other folders are private folders that prohibit detection of information from the other host. The reservation acquisition condition folder 331 has a reservation acquisition condition 332, the acquisition file folder 341 has an acquisition file 342, and the provision file folder 351 has a provision file body 352. Are stored respectively. The number of the partner host 3 is not limited to one, and there may be a plurality of hosts.

When the host 1 is connected to the network 4, the file exchanging software 11 communicates with the file exchanging software 21 of the exchanging host 2, and the file exchanging software 11 and 21 cooperate with each other to exchange with the host 1. Host 2
Synchronize information between folders.

FIG. 2 shows the synchronization relationship between the exchange folders 13 and 23 of the own host 1 and exchange host 2. The first synchronization function based on the cooperation of the file exchange software 11 and 21 compares the acquisition file folder 141 of the own host 1 and the acquisition file folder 242 of the exchange host 2 on a file-by-file basis. 1 is copied to the acquisition file 142 of the own host 1 from the exchange host 2. If the file names are the same and the information bodies are different, a function of changing the file name and copying is provided by setting the file exchange software 11.

The second synchronizing function by the cooperation of the file exchanging software 11 and 21 is the exchanging folder 13 of the host 1.
And the exchange folder 23 of the exchange host 2 are compared, and each information of the exchange host 2 is updated with the information of the own host 1 except for the acquisition file folders 141 and 241. That is, the reservation acquisition condition 232 of the exchange host 2 is the own host 1
The reservation file acquisition condition 131 is updated, and similarly, the provided file body 252 is updated with the provided file body 152, and the file list 262 is updated with the file list 162.

FIG. 3 is a flow chart of the folder synchronization processing in the own host 1 and the exchange host 2 in FIG. In FIG. 3, first, when the own host 1 is connected to the network 4 and the exchange host 2 receives the connection notice (step 501), whether or not the read / write process is being performed by the reservation search process or the access from the partner host 3. Is checked (step 502). If the process is in progress, step 502 is periodically repeated until the process is completed. If it is not being processed, stop accepting access from the partner host 3,
The reservation search of the exchange host 2 is suspended (step 50).
3). The reservation acquisition condition file 232 is compared with the reservation acquisition condition 132 of the host 1 (step 504). If there is no difference, the process jumps to the next step (step 505-N). The provided file body 132 of No. 1 is synchronized by the difference update (step 506). The acquisition file 242 is compared to see if there is a file that does not exist in the acquisition file 142 of its own host (step 507), and if there is not, jump to the next step (step 5
08), if there is, the relevant file is additionally updated from the acquisition file 242 to the acquisition file 142 of the own host (step 509). However, the files with the same name are renamed. The provided file body 252 is compared with the provided file body 152 of the own host 1, and if there is no difference, jump to the next step (step 511-N). If there is a difference, the provided file body 252 is provided as the provided file body of the own host 1. Synchronize by updating the difference in 152 (step 51).
2). The file list 262 is compared with the file list 162 of the own host 1 (step 513), and if there is no difference, the process jumps to the next step (step 514-N). If there is a difference, the file list 262 is changed to the file list of the own host 1. 16
In step 2, the difference is updated to synchronize (step 515). After the above processing is completed, reservation reservation suspension is released and access acceptance is restarted (step 516).

FIG. 4 shows the flow of information exchange processing of the present invention. If the exchange host 2 is searched by the partner host 3 (step 601), the file list folder 261
The file list 262 is searched (step 602), and if it does not correspond to the search request, the process is terminated without returning anything (step 603-N). If the portion corresponding to the search request is found, the corresponding file list and setting conditions are answered (step 604). This file list 262 includes information about file names, file attributes (outline, size, format, etc.), electronic signature necessity, encryption necessity, contract terms, price, payment method, and other file provision conditions in case of payment. It is included.

When there is a file acquisition request from the partner host 3 (step 605), the electronic signature is verified and the payment method is confirmed in accordance with the file providing conditions in the file list 262 (step 606). When the condition is not satisfied (step 607-N), the notice of refusal is transmitted to the partner host 3 (step 608). If the conditions are met, the file of the relevant information is taken out from the provided file body 252 (step 609), once decrypted (step 610), encrypted with the other party's public key (step 611), and electronically signed with his / her own private key. Then, the encrypted file is transmitted to the partner host 3 (step 612) (step 613).

FIG. 5 shows the exchange host 2 to the partner host 3
The flow of the reservation search for is shown. The file exchange software 21 of the exchange host 2 issues a search request to the partner host 3 based on the setting of the reservation acquisition condition 232 (step 70).
1). The reservation acquisition condition includes a file name (wild card), file attribute, size limit, maximum response waiting time, handling of the same name file, acquisition possible condition (price, payment method, etc.). The reply from the host 3 is waited for (step 702), and if there is no reply within the designated time, the process ends here (step 703-N).
If there is a reply, the acquisition condition from the other party is determined (step 704). If they do not match, the process ends (step 705-N). Host 3 if they match
A file acquisition request is made to (step 706). The system waits for an incoming call from the partner host 3 (step 707) and ends the process if no incoming call arrives within the designated time (step 708).
-N). When there is an incoming call, the contents such as the file name and the electronic signature are confirmed (step 709). If it is wrong, the process is terminated (step 710-N). If OK, it is stored in the acquisition file 242. However, if a file with the same name already exists, the name is changed (step 71).
1).

According to this embodiment, since the exchange host is always connected and the reservation search is performed, it is possible to periodically search for a desired file without constantly connecting the host 1 to the network. Further, since the exchange host can always open its own provided file, it is possible to exchange files with the partner host 3 at any time.

FIG. 6 shows the flow of encryption of the provided file. This process is performed for each file. The host 1 judges whether or not the additional provision file 17 exists (step 801), and if there is no additional provided file 17, the processing is terminated (step 802-N). If there is, a target key of the symmetric key cryptosystem (private key cryptosystem) is generated (step 803), the provided file is encrypted by using this symmetric key (step 804), and the used target key is the public key of the user. To encrypt (step 805). The encrypted file is written in the provided file body 152 (step 806).

FIG. 7 shows the flow of decrypting the acquired file. This process is performed for each file. If there is an acquisition file to be decrypted (step 851), the symmetric key is decrypted with its own private key (public key cryptosystem) (step 85).
3) Decrypt the obtained file using the symmetric key (step 854).

According to the present embodiment, since the file body is encrypted and the electronic signature is used for transmission, wiretapping,
It can prevent tampering and spoofing attacks. In addition, the electronic signature can be applied to file exchange with limited members and file exchange with qualification requirements.

8 and 9 are views showing a method of installing the replacement host. FIG. 8 shows a case in which the replacement software 2 is installed in the home server of the home, and the synchronization with the home host 1 in the home and the home host 6 when using mobile are also realized. FIG. 9 shows a case where an external commercial server or the like operates as a proxy host. In this case, the host 1 may be fixed or mobile.

According to this embodiment, the home server 5 shown in FIG.
Alternatively, by adding the firewall function to the commercial server 7 in FIG. 9, it is possible to prevent unauthorized access, virus, bastion attack, and the like. Further, in order to obtain an information exchange environment in which unauthorized access, a virus, a stepping stone attack, etc., which is dangerous with a constant connection, is prevented, the installation method can be selected by comparing the safety and cost. Further, it can be sold as a household product or an operation service.

Although the present invention has been specifically described above, the present invention is not limited to the above embodiments.

[0026]

EFFECTS OF THE INVENTION In addition to the own host that connects to the network whenever necessary, the information exchange host is always connected to the network as a proxy of the own host, and the folder of the own host and the folder of the information exchange host are synchronized. Due to
Information can always be exchanged without constantly connecting the host to the network. By using encryption and electronic signature, it is possible to realize an information exchange environment that prevents eavesdropping, falsification, spoofing, etc. when there are qualification requirements such as information exchange environment and transactions by limited members. Depending on the method of installing the exchange host as a proxy, it is possible to select an information exchange environment that prevents unauthorized access, viruses, bastion attacks, etc., which are dangerous with constant connection. Moreover, the environment can be provided as a product or a service.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a system that implements an information exchange method of the present invention.

FIG. 2 is a block diagram showing the synchronization relationship between the exchange folders 13 and 23 of the own host 1 and exchange host 2 in FIG.

3 is a flowchart of a folder synchronization process between the own host 1 and the exchange host 2 in the embodiment of FIG.

FIG. 4 is a flowchart showing a flow of information exchange processing of the present invention.

FIG. 5 is a flowchart showing the flow of a reservation search from the exchange host 2 to the partner host 3 according to the present invention.

FIG. 6 is a flowchart showing a flow of encryption of a provided file.

FIG. 7 is a flowchart showing a flow of decrypting an acquired file.

FIG. 8 is a configuration diagram showing a method of installing a replacement host.

FIG. 9 is a configuration diagram showing a method of installing a replacement host.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04L 29/08 H04L 13/00 307Z // H04L 9/10 9/00 621Z (72) Inventor Fumio Noda Tokyo 1-280, Higashi-Kengokubo, Kokubunji-shi F-Term in Central Research Laboratory, Hitachi, Ltd. (reference) 5B017 AA07 BA07 CA16 5B082 HA03 HA05 5B085 AA01 BA07 BG02 BG04 BG07 5J104 AA01 AA09 JA21 LA03 LA06 5K034 EE09 FF01

Claims (5)

[Claims] 1. An information exchange host, which is always connected to the network, is provided separately from the own host connected to the network whenever necessary, and information retrieval from the other host is provided for each of the own host and the information exchange host. Forbidden public information storage means, private information storage means for prohibiting information detection from the other host, and at least acquisition information storage means for storing newly acquired information, and the other host, own host and information exchange Mutual information retrieval with the host, information request, information exchanging means having information communication function, the information in the acquired information storage means of the information exchange host, triggered by the network connection of the own host, A first synchronous machine that compares the information in the acquired information storage means of the own host and copies information that does not exist in the own host from the information exchange host to the own host. Excluding the public information storage means of the own host, the public information storage means of the information exchange host, and the obtained information storage means, the private information storage means of the self host and the private information storage means of the information exchange host The information stored in each host is compared, the information of the own host is copied to the information exchange host so that the information stored in the information exchange host matches the information stored in the own host, and the mismatch information is deleted from the information exchange host. Synchronizing means having a second synchronizing function is provided in each of the information exchanging means of the own host and the information exchanging means of the information exchanging host, and the information exchanging host communicates with the own host and the other host. An information exchange system for network-connected devices, which relays the information exchange of. 2. The information exchange means according to claim 1,
The private information storage means has means for encrypting and holding all the information, and in response to an information acquisition request from the partner host, authentication processing of the partner host, information provision condition confirmation processing, decryption processing of the encrypted information. And a re-encryption processing means based on the public key of the other host, an information exchange system for network-connected devices. 3. A method for exchanging information between network-connected devices for exchanging information between a plurality of hosts connected to a network, the host being connected to the network whenever necessary, and the other party being connected to the network. When exchanging information with a host, an information exchanging method for a network-connected device, characterized in that information is exchanged via an information exchanging host that is always connected to the network. 4. The information held by the information exchange host is compared with the information held by the own host, triggered by the network connection of the own host, and information not existing in the own host is copied from the information exchange host to the own host. 4. The method for exchanging information of network-connected devices according to claim 3, wherein: 5. The information exchange host compares the information possessed by the information exchange host with the information possessed by the self host when triggered by the network connection of the self host so that the information exchange host and the information stored in the self host match. 5. The information exchange method for network-connected devices according to claim 3, wherein the information of the own host is copied to the information exchange host, and the mismatch information is deleted from the information exchange host.