JP2001195421A - Distributed retrieving device and medium for storing distributed retrieval program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a distributed retrieving device, capable of performing retrieval reflecting the response state of resources information existing on a network and a distributed retrieval program storage medium. SOLUTION: This distributed retrieval program storage medium 90 stores a distributed retrieval program 95, provided with a retrieving means 91 which receives a retrieval request from a user and retrieves resources information stored in its own database and the databases of the other distributed retrieving devices existing on the network with status information taken into consideration. The device is also provided with a registering means 92, which receives a registration request to register the resources information in the database and registers the resources information in the database, a transfer means 93 transferring the resources information stored in the database to the other distributed retrieving devices existing on the network, and a status information updating means 94 which obtains status information which is newer than the resources information stored in the database and updates the status information stored in the database.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a distributed search device which is distributed and arranged and forms a network, and a distributed search program storage medium storing a distributed search program for operating the distributed search device on a computer.

[0002]

2. Description of the Related Art As networks have evolved today and the number of computers connected to the networks has become enormous, and the enormous number of computers perform a wide variety of services, each of the computers has become It has become impossible to know all the information resources that have. Therefore, a framework for accurately searching for necessary information resources from a vast amount of information resources existing on a network has been required.

[0003] In the following, information and services provided by a computer are collectively referred to as "information resources" in the sense of intangible materials that are the basis of the information industry.

As a framework for searching for information resources, Yah
oo (http://www.yahoo.com/)
And AltaVista (http: // altavis
ta. digital. com) is provided. This search engine collects resource information indicating a place where an information resource is provided or the like by registering with a resource information provider or searching by a search program called a Web robot, and constructs a resource information database. An information resource is searched based on the resource information. However, in many cases, the search response tends to be poor due to centralized management of the resource information, the amount of information communication by the Web robot is large, and the collected resource information is Due to the suspension of the service, the movement of the location of the information resource, the change of the content of the information resource, and the like, there is a problem that the so-called obsolete resource information, which does not reflect the current state of the information resource, is caused.

In order to solve these problems, a method of constructing a distributed search network comprising a large number of agents (distributed search devices) for exchanging resource information with each other and managing each resource information and providing a search service has been proposed. Conceivable.

FIG. 1 is a conceptual diagram showing a distributed search network.

As shown in FIG. 1, a distributed search network 1 is composed of a large number of agents 2 whose partners for exchanging resource information are determined. The partner with which each agent exchanges resource information is represented by the line segment 3 in the figure, and the fact that another agent is determined as a partner with respect to one agent is referred to as "having a neighbor relationship".

[0008] The resource information provider 4 provides the resource information to the distributed search network 1, the distributed search network 1 holds the resource information as described later, and the resource information searcher 5 sends the resource information to the distributed search network 1. Requesting a search causes the distributed search network 1 to substantially search for information resources.

FIG. 2 is a diagram showing how resource information is provided.

[0010] The provider 4 transmits the resource information 6 on the information resources that he or she knows to the nearest agent 2a in the form of an advertisement.
The resource information described in the advertisement is retained, and the advertisement is further transmitted to the agents 2b and 2c having a close relationship. In this way, the resource information is transmitted to the agents one after another, and the number of agents that acquire the resource information increases, but the transmission range of the resource information depends on the cost for transmitting the resource information and the holding of the acquired resource information. The cost is limited based on the total cost.
In the following, this cost that is comprehensively considered is simply referred to as “cost”.

FIG. 3 is a diagram showing a state where a search request for resource information is received.

The searcher 5 issues a resource information search request 7 to the nearest agent 2d, and the agent 2d receiving the search request searches for the resource information held by the agent 2d and sends the search request to the advertisement. As in the case, the information is transmitted to the nearby agents 2e and 2f. Here, the range in which the search request is transmitted is also limited based on the cost. When the search request reaches the agent 2g having the resource information corresponding to the search request, the agent 2g returns the search result.

FIG. 4 is a diagram showing how the search result is returned.

The search result 8 is returned to the searcher 5 while following the route along which the search request was transmitted in reverse. The agents 2d, 2e, and 2h on the route update their own resource information based on the contents of the search result to be relayed, and try to always have new resource information. This method distributes the load by not centrally managing resource information, and tends to transmit a large amount of resource information required there to agents in areas where there is demand. The cost required for managing the resource information of the agent can be reduced.

However, in this method, since each agent is independently managed by each manager, it is impossible for all agents to change resource information all at once.

[0016]

Therefore, when an information resource becomes unavailable, the resource information provider does not advertise that the resource has become unavailable, or even if it does,
It takes time for the information to be transmitted to all the areas where users actually use it, and it tries to use the resource information that has already become invalid and tries to use it. The problem had arisen.

Even if the information resource is usable and responds to access, the same problem as described above occurs if the response time is extremely long.

In view of the above circumstances, it is an object of the present invention to provide a distributed search device and a distributed search program storage medium capable of performing a search reflecting the response status of resource information on a network.

[0019]

According to the present invention, there is provided a distributed search apparatus for storing resource information including location information of information resources which are distributed and form a network, receive information, and return information upon access. Is one of a plurality of distributed search apparatuses each having a database to be searched, and receives a search request from a user, and receives its own database and the database of another distributed search apparatus on the network. Search means for searching for the resource information stored in the database, registration means for receiving a registration request for registering the resource information in its own database, and registering the resource information in its own database, and Transfer means for transferring the resource information to another distributed search device on the network. In, the above-mentioned database,
As the resource information, resource information including the position information and status information indicating a response state when the resource information is accessed is stored, and the search means considers the status information. Search for resource information by obtaining newer status information than the status information contained in the resource information stored in its own database and including it in the resource information stored in its own database. Status information updating means for updating the status information stored in the storage device.

Here, the status information updating means includes:
Mediating access to the information resource by the user, obtaining status information based on the result of the access, and updating status information included in the resource information stored in its own database. Is preferred.

The status information updating means may return an access using the position information included in the search result returned by the returning means. It is also preferable that the status information based on the access result is obtained by monitoring, and the status information included in the resource information stored in its own database is updated.

Further, the status information updating means includes:
By accessing the information resource using the location information included in the resource information stored in its own database, obtaining status information based on the result of the access, and obtaining the resource information stored in its own database Updating the status information included in the information is also one of the preferable modes.

Further, the status information updating means obtains the status information from another distributed search device on the network, and updates the status information included in the resource information stored in its own database. It is also one of the preferable embodiments to perform the operation.

A distributed search program storage medium according to the present invention that achieves the above object includes location information of an information resource that is distributed and arranged and forms a network and that receives information and returns information when the resource information is stored. A distributed search program for operating a computer system as one distributed search device among a plurality of distributed search devices each having a database for storing resource information including status information indicating a response state when access is received is stored. A distributed search program storage medium comprising:
A search unit that receives a search request from a user and searches for resource information stored in its own database and a database of another distributed search device on the network in consideration of the status information; Receiving a registration request for registering information in its own database, registering means for registering resource information in its own database, and transferring resource information stored in its own database to another distributed search device on the network Transferring means for obtaining status information newer than the resource information stored in its own database, and updating status information included in the resource information stored in its own database. Is stored.

The distributed search program according to the present invention will be described only in its basic form, but this is for the sake of simplicity of explanation. In addition to the above-described distributed search program in the basic mode, various forms of the distributed search program corresponding to the above-described mode of the distributed search device are included.

Further, in the distributed search device of the present invention and the distributed search program, the same names as the first receiving means and the updating means are given to the constituent elements constituting them, In the case of a distributed search device, it mainly refers to the state of connection between software and hardware that perform such an operation, and in the case of a distributed search program,
It mainly refers to the part of the software that performs such an action.

[0027]

Embodiments of the present invention will be described below.

FIG. 5 is a diagram showing a part of a distributed search network constituted by an embodiment of the distributed search device of the present invention.

Here, two distributed search apparatuses 100, 200 and three client machines 300, 400, 500 each constituted by a computer system are illustratively shown. The client machines 300, 400, and 500 are connected to each other via a communication network 600. 2
The computer systems constituting the distributed search devices 100 and 200 are high-speed and large-capacity computer systems generally called workstations. Further, the two distributed search devices 100 and 200 function as agents constituting a part of a distributed search network having the same structure as the network structure shown in FIG.
The resource information searcher and the resource information provider can access the distributed search network via the client machines 300, 400, 500.

Each of the distributed search devices 100 and 200 and each of the client machines 300, 400 and 500 are provided with a CPU,
A main unit 101, 201, 301, 401, 501 containing a main storage device, a hard disk, a communication board, etc .;
Display screens 102a, 202a, 302a, 4 in response to instructions from main units 101, 201, 301, 401, 501
Display unit 1 for displaying images and character strings on 02a and 502a
02, 202, 302, 402, 502, distributed search devices 100, 200 and client machines 300, 40
Keyboards 103, 203, 303, 403, 5 for inputting an instruction of a resource information searcher or an administrator at 0,500
03, display screens 102a, 202a, 302a, 402
a, a mouse 104, 204, 304, 40 for inputting an instruction corresponding to an icon or the like displayed at that position at the time of specifying an arbitrary position on 502a
4,504.

The main body parts 101 and 201 further have an external appearance
FD loading ports 101a and 201a for loading a floppy disk (not shown) and MO700; MO loading port 101
b, 201b, and a floppy disk driver, a MO, which drives and accesses a floppy disk or MO 700 loaded from the loading ports 101a, 201a; 101b, 201b.
A driver is also built in.

Similarly, the main body parts 301, 401, 501
Is a floppy disk (not shown), CD-
FD loading ports 301a and 401 into which ROM 800 is loaded.
a, 501a; CD-ROM loading ports 301b, 401
b, 501b, and their loading ports 301a, 401a, 501a;
A floppy disk driver and a CD-ROM driver for accessing a floppy disk or a CD-ROM 800 loaded from 01b and 501b are also incorporated.

In the following description, two distributed search devices 10
The distributed search device 100 will be described as a representative of 0 and 200.

FIG. 6 is a hardware configuration diagram of the distributed search device (computer system) having the appearance shown in FIG.

The hardware configuration diagram includes a central processing unit (CPU) 111, a RAM 112, a hard disk controller 113, a floppy disk driver 1
14, MO driver 115, mouse controller 11
6, a keyboard controller 117, a display controller 118, and a communication board 119 are shown, which are interconnected by a bus 110.

Floppy disk driver 114, MO
As described with reference to FIG. 5, the driver 115 loads the floppy disks 710 and MO700, respectively, and loads the loaded floppy disks 710 and MO700.
Is to access.

The communication board 119 is a communication network 6
00 is connected.

FIG. 6 shows the hard disk 12 accessed by the hard disk controller 113.
0, a mouse 104 controlled by a mouse controller 116, a keyboard 103 controlled by a keyboard controller 117, and a CRT display 102 controlled by a display controller 118.

The MO 700 stores an agent program which is an example of the distributed search program according to the present invention.
The agent program is read from 00 and the bus 1
10 and is stored in the hard disk 120 by the hard disk controller 113. In actual execution, the agent program in the hard disk 120 is loaded on the RAM 112 and
11 is executed. As a result, the computer systems 100 and 200 having the appearance shown in FIG. 5 operate as agents which are one embodiment of the distributed search device of the present invention.

MO in which the agent program is stored
Reference numeral 700 denotes an embodiment of the distributed search program storage medium of the present invention. Further, the hard disk 120 in which the agent program is stored is also one embodiment of the distributed search program storage medium of the present invention. Further, when the agent program is downloaded to the floppy disk 710 or the like, the floppy disk 710 or the like to which the agent program is downloaded is also an embodiment of the distributed search program storage medium of the present invention.

Each of the embodiments of the distributed search apparatus of the present invention, which will be described later, has the appearance and the hardware configuration shown in FIGS. 5 and 6.

In the distributed search device of the present invention, the structure of the distributed search network is determined by storing information for specifying the distributed search devices (agents) having a close relationship with each other.

In the following description, the two terms "distributed search device" and "agent" are used as synonyms. However, from the viewpoint of the constituent elements of the device, the distributed search device is used, From an economic point of view, agents are used.

FIG. 7 is a diagram illustrating the principle of the distributed search device according to this embodiment.

The distributed search apparatus according to the present embodiment includes a plurality of distributed search apparatuses each having a database for storing resource information including location information of information resources which are distributed and form a network and receive and return information when accessed. One of the devices is a distributed search device.

As shown in FIG. 7, this distributed search device 10
Receives an advertisement relating to an information resource from an information resource provider, notifies the information resource provider as needed, and receives an information resource search request from a user, and transmits the result to the user. Inquiry processing unit 12 to return to
And an agent interface 13 for exchanging advertisements, inquiries and results with other distributed search devices, and an information resource database for storing resource information sent from the advertisement processing unit 11 and resource information received from the agent interface 13 14, an information resource access processing unit 15 that accepts a user's access request to an information resource and returns a result to the user, and the distributed search device 10 sends an access request from the user to the information resource, and Information resource access interface 1
And an information resource access control unit that mediates an access request to the information resource by the user to the information resource through the information resource access processing unit 15 and the information resource access interface 16 and receives a response to monitor the state of the information resource. 17 and the advertisement related to the information resource received from the advertisement processing unit 11 or the agent interface 13, the information is stored in the information resource database 14, and the advertisement information is transmitted to another agent through the agent interface 13 according to the available cost. And an information resource data control unit 18 for transmitting information.

The information resource data control unit 18 further includes an inquiry processing unit 12 and an agent interface 13
Such as searching the information resource database 14 in response to the inquiry about the information resource from the client, returning the search result to the inquiry processing unit 12 or the agent interface 13, and forwarding the inquiry to another agent through the agent interface 13. Also do.

The information resource database 14 in the distributed search device 10 of this embodiment stores, as resource information, resource information including not only status information but also status information indicating a response state when the resource information is accessed. In this embodiment, the information resource access control unit 17 and the information resource data control unit 18 search for resource information in consideration of the status information.

The information resource database 14 in the present embodiment corresponds to the database according to the present invention, and the information resource access control unit 17 and the information resource data control unit 18 in the present embodiment It is equivalent to the status information updating means referred to in
In addition, the information resource data control unit 18 in the present embodiment
Corresponds to the search means, the registration means, and the transfer means according to the present invention.

A plurality of agents similar to the distributed retrieval apparatus 10 described above are connected by a communication line to form a logical network, and a user uses information resources through these agents. It is not necessary that all sessions with the information resource be performed through the agent.

Therefore, if the user tries to access an information resource but cannot use it, the agent can detect that the information resource is unavailable. Then, when another user performs a search in order to use the information resource next time, the information is used, and when presenting the search result to the user, information about the unusable information resource is deleted. Or make it appear at the end of the search result, it is possible to suppress access to unusable information resources. Advertisement of information about resources that are found to be unusable to nearby agents can also inform other agents of the fact that resources have become unavailable. And more effective resource information search.

Next, a normal operation of the distributed search device 10 will be described.

The resource information provider provides the nearest agent with a URL (Universal) related to the information resource.
Resource Location (namely, location information of the information resource according to the present invention), a name, and information such as keywords expressing service contents are presented to the distributed search device 1.
Request an advertisement at 0. Distributed search device 1 that has received it
0 indicates the content of the advertisement in the advertisement processing unit 11,
The information is passed to the information resource data control unit 18, where the advertisement information on the information resource is stored in the information resource database 14,
Agent interface 1 according to a virtual cost (for example, time spent for advertisement, actual cost required for communication and use of database, etc.) for limiting an advertisement range.
3, the information is transmitted to other neighboring agents. When time is used as the cost, a clock may be referred to. Each time the advertisement information passes through the agent, the cost decreases, and the transmission of the advertisement information is repeated until it disappears. In the case of searching for resource information, when a search request for an information resource is made to the distributed search device 10, the content of the search request is confirmed by the inquiry processing unit 12, and the data corresponding to the prosecution request is checked by the information resource data control unit 18. A search is made from the information resource database 14. And, as in the case of resource information ads,
The search request is also transferred to another agent according to the cost, and waits for a response from the transfer destination. Then, when the responses from all the transfer destinations are completed, the search result is returned to the information resource searcher through the inquiry processing unit 12. that time,
The clock may be referred to and the search result may be returned to the information resource searcher when the timeout occurs, even if there is no response from all transfer destinations.

Next, the operation of the distributed search device according to the present invention will be described.

When an information resource user uses an information resource, an access request is normally made using a browser,
An access request, specifically, for example, a URL is passed to the information resource access processing unit 15 of the distributed search device 10 (step S1). Usually, the information resource searcher is often the information resource user.

In general, the services of many information resources are:
Since it is often provided by the WWW (World Wide Web), http (Hyper T)
Assuming that the access request is given by the Ext Transfer Protocol, the access request given to the agent may be, for example, “GET agent_url? url = resource.
ce_url ”. At the time of search, the URL of the information resource in the search result returned from the agent to the user does not directly indicate the URL of the information resource but passes through the agent. URL, eg, “agent_url? url = resource_u
rl ".

The information resource access processing unit 15 analyzes the character string of the given URL, extracts the URL “resource_url” representing the actual location information of the information resource, and instructs the information resource access control unit 17 to “resource_url”. Make a request to access.

The information resource access control unit 17 receives the request and sends it through the information resource access interface 16.
Access the specified information resource. At this time, instead of sending the character string given by the information resource user as it is, a character string “HEAD resource_url” is sent to check whether the information resource exists and can be used. That is, in this case, since the information content itself is not required, “HEAD” is used without using “GET”.

If the information resource is unavailable for some reason, the fact is notified to the information resource user.
If available, send a redirection message back to the information resource user.

The format of the redirection message is, for example, “Location: resource_url”, and the browser that receives this message usually immediately requests the access to the information resource access processing unit 15, and the information resource access processing unit 15 transmits the message to the “Locatio”.
The information is accessed by accessing the URL “resource_url” indicated by “n”, displayed, and behaves as if it had been accessed from the beginning.

Once the resource information of the agent has been registered in the information resource database 14, it may be difficult to update it. For example, it is assumed that an information resource is advertised from a certain agent and the resource information is propagated to a certain range on the network. After that, it is assumed that the resource information is propagated to a wider range by many users searching. In this situation, it is assumed that the service of the information resource is stopped or the URL is changed for some reason, and the original agent requests deletion and change of the resource information. Then, since both the deletion request and the change request are made in the form of the advertisement, the deletion request and the change request are not transmitted to the same extent as the range where the advertisement of the information resource was originally performed. The transmitted range depends on the network environment at that time, and is not necessarily the same range. Moreover, since the resource information provider or the agent who first advertised the resource information has difficulty in knowing which other agent is transmitting the information,
An agent that has the original resource information but has not been deleted or changed may exist.

A user who requests such an agent to obtain a search and obtains a result may obtain information on an invalid information resource. However, if any one of them actually accesses the information, it is possible to obtain information on whether the information resource is available or not. By deleting from the database, other users do not encounter the same inconvenience, and it is possible to obtain more appropriate search results.

Therefore, in the distributed search apparatus 10 of the present embodiment, the resource information database 14 includes, as resource information, resource information including location information and status information indicating a response state when the resource information is accessed. The information resource data control unit 18 serving as a search means is configured to search for resource information in consideration of status information. The access control unit 17 and the information resource data control unit 18 obtain status information that is newer than the status information included in the resource information stored in the resource information database 14 and store the status information in the resource information database 14. It is configured to update status information included in the resource information.

FIG. 8 shows an example of the configuration of the resource information database in this embodiment.

The resource information database 36 has a UR
In addition to the L field 36a, the service name field 36b, the keyword field 36c, the provider field 36d, etc., a status field 36e which is status information indicating a response status when the resource information is accessed, a final status confirmation date / time field 36f, etc. Is provided.

In the example shown in FIG. 8, when the resource information can be accessed, that is, when the status code of http is 2
In the case of 00, “1” is stored in the status field 36e, and “Timeout” or “Sever
For transient and potentially recoverable errors such as "Not Responding", the status field 36
e, “0” is stored, and “Host Not Found”
In the case of a fatal error such as “d” or “Not Found” (404), “−” is added to the status field 36e.
For example, when the resource information can be accessed, the status is set to “active”; when the resource information cannot be accessed, the status is set to “disable”. The state may be further subdivided according to the type.

By the way, the distributed search device 10 of the present embodiment
When the search results are displayed to the user, when the search results from the other agents are completed, the information is merged with the data in the resource information database 14, and the state of each information resource is examined. The search results are sorted according to the degree of matching with the search request and presented to the user.

In the order in which the search results are presented, available information resources are displayed at the top, and unusable information resources are displayed at the bottom, so that the actually available information resources can be highlighted. By doing so, the user
The probability of selecting an unavailable information resource is reduced. As the similarity between the original search request and the search result, it is desirable to use the frequency of appearance of the keyword of the search request in the information resource, which is often used.

The following three methods are available for calculating the modified fitness by combining the state of the information resource and the fitness by the keyword. In the following equation, kw represents a keyword, and m represents the degree of matching by the keyword. m takes a value of [0, 1] by normalization processing.

(1) A method of subtracting the degree of inconvenience α of the information resource state from the degree of conformity m by the keyword kw

[0071]

(Equation 1)

(2) A method of applying a bias β in accordance with the state of information resources from the degree of conformity m by the keyword kw

[0073]

(Equation 2)

(3) Point-weighted comprehensive evaluation method based on fitness m based on keyword kw and information resource status

[0075]

(Equation 3)

Here, 0 <m _stat (url) <1 is a parameter corresponding to the state of the information resource. If the information resource is available, it takes “1”, and the state where the most serious error is obtained Then, "0" is taken. γ is a weight for m _stat and takes a value of [0, 1]. Also, m _kw is normalized,
It is modified so as to take the value of [0, 1].

[0077] However, a set of information resources and keywords that are shown in the url each _{[kw 0, ..., kw n} ] mkw the goodness-of-fit of the _{(url, [kw 0, ...} , kw n]), in the state of information resources M (url,
[Kw ₀ ,..., Kw _n ]).

By sorting the search results in accordance with the degree of conformity of the information resources obtained in this way and presenting them to the user, the user can know the state of the information resources accurately, and can perform efficient search. It can be performed.

[0079]

Next, the present invention will be specifically described with reference to examples.

FIG. 9 is a schematic block diagram of a first embodiment of the distributed search apparatus of the present invention.

As shown in FIG. 9, this distributed search device 20
Is a distributed search device of a plurality of distributed search devices that are distributed and form a network,
It has an information resource database 24 that stores resource information including information on the location of information resources that receive access and return information. The information resource database 24 stores resource information including location information as resource information and status information indicating a response state when the resource information is accessed. That is, as shown in FIG. 8, the resource information including the status information indicating the response status when the resource information is accessed, such as the status field 36e and the final status confirmation date / time field 36f, is stored in the information resource database 24. Is done.

The distributed search device 20 receives a search request from a user, and stores the resource information stored in its own information resource database 24 and the information resource databases of the other distributed search devices on the network. Search means for performing a search in consideration of the status information described above, registration means for receiving a registration request for registering resource information in its own information resource database 24, and registering resource information in its own information resource database 24, Transfer means for transferring the resource information stored in its own information resource database 24 to another distributed search device on the network; and status information contained in the resource information stored in its own information resource database 24 Newer status information than the information resource database 24
And status information updating means for updating status information included in the resource information stored in the storage device.

The information resource access control section 27 and the information resource data control section 28 in this embodiment correspond to the above-mentioned search means, registration means, transfer means, and status information update means.

This status information updating means obtains status information based on the result of the access by mediating the user's access to the information resource, and includes the status information in the resource information stored in its own information resource database 24. It is configured to update the status information that is being updated.

In addition to the above, this distributed search device 20
An advertisement processing unit 21, an inquiry processing unit 22, an agent interface 23, an information resource access interface 26, and a clock 29 having the same functions as those in the distributed search device 10 shown in FIG.

FIG. 10 is a flowchart of an operation based on an access request by an information resource user.

FIG. 10 shows an information resource user 35 in the distributed search device 20 (see FIG. 9) according to the first embodiment of the present invention.
Of the operation based on this access request is shown.

When the information resource user 35 uses the information resource, the resource interface 32 accepts the access request and passes the URL to the information resource access processing unit 25 of the distributed search device 20 (step S1).

The information resource access processing unit 25 analyzes the character string of the given URL, extracts the URL representing the actual information resource location information, and extracts the information resource access control unit 27.
(Step S2).

The information resource access control unit 27 accesses the specified information resource through the information resource access interface 26 (step S3).

The result of access to the information resource (step S
4) If there is a response, proceed to step S5; otherwise, proceed to step S7.

In step S5, even if there is a response, if the response is an error message, that is, if the information resource is unavailable for some reason, the process proceeds to step S7, where the error message is transmitted through the resource interface 32. The resource user 35 is notified (step S7), and the process proceeds to step S8.

On the other hand, if the response is not an error message but the information resource is available in step S5, the flow advances to step S6 to send a redirection message back to the information resource user 35 through the resource interface 32. Proceed to S8.

In step S8, the state of the corresponding URL in the resource information database 24 is updated. When the update is completed, all the processing ends.

As described above, the distributed search device 20 of this embodiment
Means that the status information updating means, that is, the information resource access control unit 27 and the information resource data control unit 28, fulfill the function of mediating the access to the information resource by the information resource user 35. By mediating, status information based on the access result is obtained, and the status information included in the resource information stored in its own information resource database 24 is updated.

In this way, the distributed search device 20 mediates the status information, so that it is possible to obtain information as to which information resources are available and which information resources are not available. You can search.

Next, a second embodiment of the present invention will be described.

The distributed search device 20 according to the second embodiment includes:
A return means for returning the search result by the search means to the user is provided, and the status information updating means monitors the access using the position information included in the search result returned by the return means, thereby performing the access. And obtains status information based on the result, and updates the status information included in the resource information stored in its own information resource database.

FIG. 11 is a schematic configuration diagram of a second embodiment of the distributed search device of the present invention.

As shown in FIG. 11, the distributed search device 40 of the second embodiment has a similar configuration to the distributed search device 20 of the first embodiment shown in FIG. The information resource access interface 26 provided in the device 20 is not provided in the distributed search device 40. The configuration other than the above is the same as the configuration shown in FIG.
A description of them will be omitted. In the distributed search device 40 according to the second embodiment, the information resource user and the information resource searcher are integrated, and the resource interface and the searcher interface are integrated.

The distributed search device 40 of the present embodiment configured as described above does not have the function of mediating access to information resources by information resource users as in the first embodiment. An inquiry processing unit 49 (corresponding to the return means according to the present invention) for returning a search result by the data control unit 48 (corresponding to the search means according to the present invention) to the information resource user 45 is provided. The control unit 47 and the information resource data control unit 48 (corresponding to a status information updating unit according to the present invention) monitor access using the position information included in the search result returned by the inquiry processing unit 49. Obtains status information based on the result of the access, and obtains status information included in the resource information stored in its own information resource database 44. It is configured to update the scan information.

Next, the operation of the distributed search device 40 will be described.

1. The search result is returned to the resource / searcher interface 42 and the information resource user / information resource searcher (user / searcher) 45 via the inquiry processing unit 49 in the form of a URL list.

2. When the information resource user / information resource searcher (user / searcher) 45 selects a URL in the search result, the resource / searcher interface 42 accesses the information resource.

3. The resource / searcher interface 42 reports the above access result to the information resource access processing unit 46.

4. The resource information database 44 is controlled by the information resource access control unit 47 and the information resource data control unit 48.
Is updated.

With this configuration, in the distributed search device 40, the information resource access processing unit 46 obtains status information based on the access result by monitoring the access returned by the inquiry processing unit 49. Since the status information of the resource information database 44 is updated, the status information of the resource information database 44 is kept up to date even though it does not have a function of mediating access to the information resource by the information resource user. be able to.

Next, a third embodiment of the present invention will be described.

FIG. 12 is a schematic block diagram of a fourth embodiment of the distributed search apparatus of the present invention.

As shown in FIG. 12, in the distributed search device 70 of the fourth embodiment, the information resource access control unit 77 and the information resource data control unit 78, ie, the status information updating means according to the present invention, By accessing the information resource using the position information included in the resource information stored in the information resource database 74, status information based on the result of the access is obtained and stored in the own information resource database 74. It is configured to update status information included in the resource information that has been entered.

In the embodiment shown in FIG. 12, the scheduler 80 refers to the clock 79, and at the time set by the administrator of the distributed search device 70, accesses the designated information resource. By examining the response, status information based on the result of the access is obtained, and the status information included in the resource information stored in the information resource database 74 is updated.

Since the other components are the same as those shown in FIG. 9, detailed description thereof will be omitted.

The present embodiment is configured as described above. In each of the above-described embodiments, unless an access is made by a user or a resource information advertisement is received from another agent.
The status information of the resource information is not updated. Therefore, if the information resource happens to be unusual even once, it will not be presented at the top when displaying the search result, and the user is less likely to select from the search result. It is difficult to update the status information. However, unavailable situations do not necessarily last forever. For example, if an accidental network failure or computer maintenance makes access inaccessible, it is quite possible that it will be available again after some time. The exact opposite situation can also occur satisfactorily. Therefore, even if the information resource is once unavailable, it is necessary to periodically monitor the availability of information resources for a while and rank the search results according to the status, thereby increasing the appropriateness of the search results. Can be.

However, if an attempt is made to update all the information resources existing in the information resource database, the load becomes extremely high and the traffic may increase. Alternatively, it is preferable to preferentially perform a search with a high search frequency.

In the distributed search device 20 according to the first embodiment shown in FIG. 9, when an agent finds information on an unavailable information resource, it not only updates its own resource information database, but also updates its own If the status information is also transmitted, more agents can know the invalid resource,
More appropriate search can be performed.

Therefore, in the third embodiment, status information is advertised.

FIG. 13 is a flowchart of an operation based on an access request in the distributed search device according to the third embodiment of the present invention. This flowchart shows the last step S
Except for 19, it is the same as the flowchart of the first embodiment shown in FIG.

When an information resource user 85 (see FIG. 12) uses an information resource, the resource interface 82
Accepts the access request and passes the URL to the information resource access processing unit 75 of the distributed search device 70 (step S1).
1).

The information resource access processing unit 75 analyzes the character string of the given URL, extracts the URL representing the actual information resource location information, and extracts the information resource access control unit 77.
(Step S12).

The information resource access control unit 77 accesses the specified information resource through the information resource access interface 76 (step S13).

The result of access to the information resource (step S
14) If there is a response, the process proceeds to step S15, and if there is no response, the process proceeds to step S17.

In step S15, even if there is a response, if the response is an error message, that is, if the information resource is unavailable for some reason, the process proceeds to step S17, where the error message is transmitted to the The resource user 85 is notified (step S17), and the process proceeds to step S18.

On the other hand, in step S15, if the response is not an error message but the information resource is available, the process proceeds to step S16, and after the redirection message is sent back to the information resource user 85 through the resource interface 82, the process proceeds to step S16. Proceed to S18.

In step S18, the state of the corresponding URL in the resource information database 74 is updated. Next, the information resource data control unit 78 advertises status information including the new state of the information resource to another agent (step S19). Fig. 1 Ends all processing when advertising ends
4 is an example of an advertisement form used in the third embodiment of the present invention.

As shown in FIG. 14, the advertisement form 50 used in the third embodiment has an agent ID 50
a, sender's address 50b, resource information title 50
c, keyword 50d, URL 50e, information resource maintainer 50f, transfer cost 50g, data input date and time 50
h, status information 50i indicating the status of the information resource, final status confirmation date and time 50j, and the like.

By the way, in the flowchart of FIG.
Although only the case where the distributed search device accesses the information resource has been described, the distributed search device 70 can be configured such that the status information updating means obtains status information from another agent on the network and Is configured to update the status information included in the resource information stored in the. That is, even when resource information is accessed from another agent, status information is obtained from that agent,
The status information included in the resource information stored in the own information resource database 74 is updated.

By doing so, the latest status information is automatically transmitted to the network, so that the effectiveness of the distributed search network can be improved.

Next, the distributed search program storage medium of the present invention will be described.

FIG. 15 is a schematic diagram showing an embodiment of the distributed search program storage medium of the present invention.

As shown in FIG. 15, the distributed search program storage medium 90 receives a search request from a user and is stored in its own database and the database of another distributed search device on the network. Search means 91 for searching for resource information in consideration of status information, registration means 92 for receiving a registration request for registering resource information in its own database and registering resource information in its own database, Transfer means 93 for transferring the stored resource information to another distributed search device on the network; obtaining status information newer than the resource information stored in its own database; Status information updating means 94 for updating status information included in the stored resource information; In which distributed search program 95 equipped is stored.

As the distributed search program storage medium 90, any medium such as an MO, an FD, and a CD-ROM may be physically used. In the system shown in FIG. 5, the MO 700 is used as a medium for storing the distributed search program storage medium 90, and the distributed search is performed by the MO driver 115 (see FIG. 6) provided in the distributed search devices 100 and 200 of the distributed search network. The distributed search program 95 stored in the program storage medium 90 is read by the distributed search devices 100 and 200.

Thus, distributed search apparatuses 100 and 200
Has a plurality of information resource databases each storing resource information including location information of an information resource that receives access and returning information, and also includes status information indicating a response state when the resource information is accessed. It operates as one of the distributed search devices.

[0133]

As described above, according to the distributed search device of the present invention, the database provided in the distributed search device
By storing resource information including location information as well as status information indicating a response state when the resource information is accessed, the resource information on the network is in a usable state. It is possible to realize a distributed search device capable of searching whether or not the search is performed.

Further, by using the distributed search program storage medium of the present invention, the above-described distributed search device can be reliably formed on a computer, and a distributed search network system can be easily formed.

[Brief description of the drawings]

FIG. 1 is a conceptual diagram illustrating a distributed search network.

FIG. 2 illustrates how resource information is provided.

FIG. 3 is a diagram illustrating a state in which a search request for resource information is received.

FIG. 4 is a diagram showing how a search result is returned.

FIG. 5 is a diagram showing a part of a distributed search network constituted by an embodiment of the distributed search device of the present invention.

FIG. 6 is a hardware configuration diagram of a distributed search device (computer system) having the appearance shown in FIG.

FIG. 7 is a diagram illustrating the principle of the distributed search device according to the embodiment;

FIG. 8 is a configuration example of a resource information database in the embodiment.

FIG. 9 is a schematic configuration diagram of a first embodiment of the distributed search device of the present invention.

FIG. 10 is a flowchart of an operation based on an access request by an information resource user.

FIG. 11 is a schematic configuration diagram of a second embodiment of the distributed search device of the present invention.

FIG. 12 is a schematic configuration diagram of a fourth embodiment of the distributed search device of the present invention.

FIG. 13 is a flowchart of an operation based on an access request in the distributed search device according to the third embodiment of the present invention.

FIG. 14 is an example of an advertisement form used in the third embodiment of the present invention.

FIG. 15 is a schematic diagram showing an embodiment of a distributed search program storage medium of the present invention.

[Explanation of symbols]

1 Distributed search network 2, 2a, 2b, 2c, 2d, 2e, 2f, 2g, 2h
Agent 3 Line segment 4 Resource information provider 5 Resource information searcher 6 Resource information 7 Search request 8 Search result 10,20 Distributed search device 11,21 Advertising processing unit 12,22 Query processing unit 13,23 Agent interface 14,24 Information Resource database 15,25 Information resource access processing unit 16,26 Information resource access interface 17,27 Information resource access control unit 18,28 Information resource data control unit 29 Clock 30 Producer interface 31 Searcher interface 32 Resource interface 33 Resource information provider 34 Information resource searcher 35 Information resource user 36 Resource information database 36a URL field 36b Service name field 36c Keyword field 36d Provider field 36 e Status field 36f Final status confirmation date and time field 40 Distributed search device 42 44 Information resource database 45 Information resource user 46 Information resource access processing unit 47 Information resource access control unit 48 Information resource data control unit 49 Query processing unit 50 Advertising form 50a Agent ID 50b Address of sender 50c Title of resource information 50d Keyword 50e URL 50f Maintainer of information resource 50g Transfer cost 50h Data input date and time 50i Status information 50j Final status confirmation date and time 70 Distributed search device 74 Information resource database 75 Information resource access processing unit 76 Information resource access interface 77 Information resource access control unit 78 Information resource data control unit 79 Clock 80 Scheduler 82 Resource interface 85 information resource user 90 distributed search program storage medium 91 search means 92 registration means 93 transfer means 94 status information update means 95 distributed search program 100, 200 distributed search device 101, 201, 301, 401, 501 main body 101a, 201a FD Loading ports 101b, 201b MO loading ports 102a, 202a, 302a, 402a, 502a
Display screen 103, 203, 303, 403, 503 Keyboard 104, 204, 304, 404, 504 Mouse 110 Bus 111 Central processing unit (CPU) 112 RAM 113 Hard disk controller 114 Floppy disk driver 115 MO driver 116 Mouse controller 117 Keyboard controller 118 Display controller 119 Communication board 120 Hard disk 300, 400, 500 Client machine 301a, 401a, 501a FD loading port 301b, 401b, 501b CD-ROM loading port 600 Communication network 700 MO 710 Floppy disk 800 CD-ROM

Claims (6)

[Claims] 1. One of a plurality of distributed search apparatuses, each of which has a database storing resource information including location information of an information resource that receives and returns information and that is accessed and forms a network in a distributed manner and forms a network. A search device that receives a search request from a user and searches for resource information stored in its own database and a database of another distributed search device on the network; A registration unit for receiving a registration request for registration in its own database and registering resource information in its own database, and transferring the resource information stored in its own database to another distributed search device on the network Means, wherein the database is the resource information as the resource information. And resource information including status information indicating a response state when the resource information is accessed. The search means searches for the resource information in consideration of the status information. And obtains newer status information than the status information contained in the resource information stored in its own database, and updates the status information contained in the resource information stored in its own database. A distributed search device comprising status information updating means for updating. 2. The status information updating means obtains status information based on a result of the access by mediating access to the information resource by the user,
2. The distributed search device according to claim 1, wherein the status information included in the resource information stored in its own database is updated. 3. A return means for returning a search result by the search means to a user, wherein the status information updating means performs access using position information included in the search result returned by the return means. 2. The distribution according to claim 1, wherein status information based on a result of the access is obtained by monitoring, and status information included in resource information stored in its own database is updated. Search device. 4. The status information updating means accesses status information resources using location information included in the resource information stored in its own database, thereby obtaining status information based on the access result. 2. The distributed search device according to claim 1, wherein the status information included in the resource information stored in its own database is updated. 5. The status information updating means obtains the status information from another distributed search device on the network, and updates status information included in resource information stored in its own database. The distributed search device according to claim 1, wherein 6. A location information of information resources which are distributed and form a network and receive and return information when accessed, and also include status information indicating a response state when the resource information is accessed. A distributed search program storage medium storing a distributed search program for operating a computer system as one distributed search device among a plurality of distributed search devices each having a database for storing resource information. A search unit that receives a search request and searches for resource information stored in its own database and the databases of other distributed search devices on the network in consideration of the status information; Accept a registration request to register in the database and save it in your own database Registration means for registering the source information, transfer means for transferring the resource information stored in its own database to another distributed search device on the network, and newer than the resource information stored in its own database. And a status information updating means for obtaining status information and updating status information included in resource information stored in its own database. Program storage medium.