JP2001028004A - Device, method, and recording medium for geographical information data retrieval, device, method, and recording medium for node information exchange, and geographic information data retrieval system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To indirectly access all geographical information data retrieval device when a location of the geographical information data retrieval device at one place is known. SOLUTION: The geographical information data retrieval system 1 is constituted by connecting geographical information data retrieval devices 10 equipped with geographical information databases 20 stored with geographical space data and a node information exchange device 40 to each other through a network 30; and each geographical information data retrieval device 10 is equipped with an input/output means 11, a node information table 12, a node information retrieval means 13, a transfer means 14, a data retrieval means 15, and a rewriting means 16 and the node information exchange device 40 is equipped with a grouping means 41, an in-group exchange means 42, and an inter-group exchange means 43.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a search device, a method, a system, and a recording medium for searching a plurality of geographic information databases existing on an electronically integrated network. The present invention relates to a method, an apparatus, and a system for efficiently distributing node information registered in a table to a geographic information data search device, and a recording medium on which the program is recorded.

[0002]

2. Description of the Related Art Conventionally, a geographic information data retrieval device (Geographic Information System: GIS) that obtains spatial data desired by a user by searching a geographic information database storing spatial data.
tems). Spatial data consists of natural features such as mountains, hills, rivers or ponds, man-made features such as buildings, houses, bridges, roads, railroad tracks, fields, or geographical spaces such as boundaries between features. Refers to data related to the component to be used. The geographic space represented by this spatial data is generally represented as a two-dimensional map.

[0003] As a service for supporting the shared use of spatial data, information on spatial data owned by each organization such as an administrative organization is stored in a database, and a user can inquire the database by inquiring the database. There is a service that allows you to obtain information about the relevant spatial data. Representative examples of this spatial data search service include the Federal Geographic Data Committee
(FGDC) clearing-house
And the Catalog of OpenGIS Consortium, Inc (OGC)
rvice (catalog service).

[0004] This OGC catalog service will be briefly described. The objects searched by the catalog service are called georesources. Georesources include spatial data (Geodata) and geographic information services (Geoservice)
There are two types. The spatial data includes a catalog entry (CatalogEntry) class and a catalog (Catalog) class.

[0005] The catalog service searches for an instance of a catalog entry class generated from attribute information (metadata) of the spatial data, instead of searching for the spatial data itself.

FIG. 16 is a diagram for explaining generation of a catalog entry instance. In FIG.
The catalog entry instance is generated based on attribute information of the spatial data. The user searches the generated catalog entry instance as a search target. As a result, the user can obtain information such as the creation date of the spatial data, the data format, the creator, and the URL of the distribution source from the search result.

[0007] A catalog class is a set of catalog entry instances that are basic elements. Further, the catalog class has functions for operating a catalog entry instance and providing attribute information of the catalog class itself. For example, adding a catalog entry
Function to operate catalog entry instance such as deletion, modification, duplication, generation of iterator for catalog entry, and acquisition of catalog entry schema, acquisition of catalog service properties, and setting of catalog service properties such as setting of catalog service properties It has a function of performing operations, and a function of performing operations on catalog instances such as duplication of the entire catalog and creation / deletion of catalogs.

FIG. 17 is a diagram for explaining a catalog service. In FIG. 17, when a user requests a search from a catalog service using a client application, a catalog entry instance corresponding to the search condition is returned as a search result.

When a plurality of geographic information data retrieval devices as described above are connected on an electronically integrated network, each of the geographic information data retrieval devices has
When a search request from a client is received using a terminal or the like connected to the network, whether there is geographic information data corresponding to the client's search request in a geographic information database associated with the geographic information data search device Perform a search for When geographic information data corresponding to the condition described in the client's search request is found, data (hereinafter referred to as metadata) describing attribute information about the geographic information data is transmitted to the client as a search result. The metadata includes items such as a data type, a data creator, and a creation date, and is required for performing a search.

[0010]

However, in the case described above, each geographic information data search device does not cooperate with another geographic information data search device. That is, each geographic information data search device is considered to be operating independently.

Therefore, if there are a plurality of geographic information data retrieval apparatuses having the above-mentioned configuration on the same network, the client must search each of the geographic information data retrieval apparatuses in order to retrieve necessary geographic information data. You must submit a search request to

FIG. 18 is a diagram for explaining a conventional search and its problems. In FIG. 18, geographic information data search devices A to F each have geographic information data and exist on a network. Client C1 is
Since the user knows that the geographic information data satisfying the search request exists in the geographic information database of the geographic information data search device B, the user submits a search request directly to the geographic information data search device B and obtains a desired search result. Obtainable. However, the client C2 does not know that the geographic information data satisfying the search request exists in the geographic information database of the geographic information search device E.
A search request is submitted to the geographic information data search device C, and a result indicating that there is no geographic information data satisfying the search request is received from the geographic information data search device C.

[0013] In the above-described embodiment of the use of the geographic information data search device, the client obtains information as to what geographic information data exists in the geographic information database provided in which geographic information data search device and the geographic information data search. It is necessary to have information on the location of the device in advance. This puts a heavy burden on the client.

[0014] An object of the present invention is to provide a client that knows the location of at least one geographic information data retrieval device.
Geographic information data retrieval device capable of indirectly accessing all geographic information data retrieval devices, device having a function of node information exchange service for distributing catalog node information, and recording medium recording these programs It is to provide.

[0015]

The present invention has the following features to attain the object mentioned above. That is,
According to one aspect of the present invention, a geographic information data search device of the present invention is a geographic information data search device including a geographic information database that stores geospatial data, and inputs external data including search conditions. An input / output means for outputting data including a search result, a node information table in which data characteristic information indicating characteristics of geospatial data is associated with device identification information for identifying a geographic information data search device, Node information search means for searching for data feature information that satisfies the search condition input by the input / output means by referring to the information table, and searching for device identification information corresponding to the searched data feature information; When the device specifying information searched by the node information searching means is not device specifying information for specifying the own geographic information data search device For spatial data retrieval device specified by the retrieved apparatus specific information, and a transfer means for transferring the search condition.

Preferably, in the geographic information data search device of the present invention, the device specification information searched by the node information search means is device specification information for specifying the own geographic information data search device. In this case, it is desirable to include a data search unit that searches geospatial data based on the search condition.

Preferably, the geographic information data search device of the present invention further rewrites the geographic information database based on geospatial data or editing instructions input by the input / output means, and inputs the data by the input / output means. It is preferable to include a rewriting unit that rewrites the node information table by writing a set of the data characteristic information and the device identification information that have been set in the node information table.

Preferably, the geographic information data search device of the present invention further includes a geographic information conversion means for converting the place name information input by the input / output means as a search condition into latitude / longitude information as a new search condition. It is desirable to provide.

Further, according to one aspect of the present invention, the node information exchange apparatus of the present invention is connected to a network in which a plurality of geographic information data retrieval apparatuses each having a geographic information database storing geospatial data are connected to each other. A node information exchange device, wherein the geographic information data search device comprises:
Input / output means for inputting external data including search conditions and outputting data including search results, data characteristic information indicating characteristics of geospatial data, and device specifying information for specifying a geographic information data search device; By referring to the node information table and the node information table, the data feature information satisfying the search condition input by the input / output means, and an apparatus corresponding to the searched data feature information. A node information search unit for searching for specific information; and if the device specifying information searched by the node information searching unit is not device specifying information for specifying the own geographic information data searching device, The transfer means for transferring the search condition to the specified geographic information data search device, and the search by the node information search means. When the specified device specifying information is device specifying information for specifying the own geographic information data search device, the data search unit searches for geospatial data based on the search condition, and the data is input by the input / output unit. Rewriting the geographic information database based on geospatial data or an editing instruction, and rewriting the node information table by writing a set of data feature information and device identification information input by the input / output means into the node information table. Means for grouping one or more geographic information data retrieval devices, comprising:
Between the geographic information data search devices in the group, input a copy of each other's node information table via the input / output means, and input the data feature information and device identification information in the copy input in the own node information table. When there is no set, between the intra-group exchange means for rewriting the own node information table by writing the set to the own node information table by the rewriting means, and a predetermined geographic information data search device of a different group, When a copy of each other's node information table is input via the input / output means, and there is no set of the data feature information and the device identification information in the copy input in the own node information table, the set is An inter-group exchange unit for rewriting the self-node information table by writing the self-node information table by the rewriting unit.

Further, according to one aspect of the present invention, the geographic information retrieval system of the present invention includes a plurality of geographic information data retrieval devices each including a geographic information database for storing geospatial data, and a node information exchange device. A geographic information data search system connected via a network, wherein the geographic information data search device inputs and outputs external data including search conditions and outputs data including search results, and geospatial data. A node information table in which data characteristic information indicating the characteristics of the information and device specifying information for specifying a geographic information data search device are associated with each other, and by referring to the node information table, the search input by the input / output means is performed. Search for data feature information that satisfies the condition, and search for device identification information corresponding to the searched data feature information Node information searching means, and when the device specifying information searched by the node information searching means is not device specifying information for specifying the own geographic information data searching device, the geographic information specified by the searched device specifying information is used. For the information data search device, when the transfer means for transferring the search conditions, and the device identification information searched by the node information search means is device identification information for identifying the own geographic information data search device, A data search means for searching geospatial data based on the search condition; and a data feature input by the input / output means, rewriting the geographic information database based on geospatial data or edit instructions input by the input / output means. The node information table is written by writing a set of information and device identification information in the node information table. The node information exchange device includes: a grouping unit that groups one or more geographic information data search devices; and a geographic information data search device within the group. When a copy is input via the input / output means, and there is no set of the data feature information and the device identification information in the copy input in the own node information table,
The intra-group exchange unit that rewrites the own node information table by writing the set in the own node information table by the rewriting unit, and the duplication of each other's node information table between the predetermined geographic information data search devices in different groups. Is input through the input / output means, and if there is no set of the data feature information and the device identification information in the copy input in the own node information table, the set is rewritten by the own node information by the rewriting means. An inter-group exchange means for rewriting the self-node information table by writing to the table.

Further, according to one aspect of the present invention, a geographic information data search method of the present invention is a geographic information data search method for searching a geographic information database storing geospatial data, the external information including a search condition. By inputting data from the, by referring to the node information table associated with data feature information indicating the characteristics of geospatial data and device identification information for identifying the geographic information data search device,
The data feature information that satisfies the input search condition is searched, the device specifying information corresponding to the searched data feature information is searched, and the searched device specifying information specifies the own geographic information data search device. If the search condition is not the device specifying information, the search condition is transferred to the geographic information data searching device specified by the searched device specifying information.

Preferably, the geographic information data search method according to the present invention, when the searched device specifying information is device specifying information for specifying the own geographic information data searching device, includes: It is desirable to search geospatial data based on the data and output data including the search results.

Preferably, the method for retrieving geographic information data of the present invention rewrites the geographic information database based on input geospatial data or an editing instruction, and sets a combination of the input data feature information and the device specifying information. Is written in the node information table to rewrite the node information table.

Preferably, in the geographic information data search method of the present invention, it is desirable to convert place name information input as a search condition into latitude and longitude information as a new search condition. According to one aspect of the present invention, the node information exchange method of the present invention is a node information exchange method for exchanging node information tables provided in a plurality of geographic information data search devices connected to a network, Geographic information data search device, input / output means for inputting external data including search conditions and outputting data including search results,
By referring to the node information table and the node information table in which the data feature information indicating the feature of the geospatial data and the device identification information for identifying the geographic information data search device are input by the input / output means. Node information searching means for searching for data feature information satisfying the searched search condition and searching for device identification information corresponding to the searched data feature information; and device identification information searched for by the node information searching means. A transfer unit configured to transfer the search condition to the geographic information data search device specified by the searched device identification information when the device information is not device identification information for specifying the geographic information data search device; When the device specifying information searched by the search means is device specifying information for specifying the own geographic information data search device A data search unit for searching geospatial data based on the search condition; and a data input unit that rewrites the geographic information database based on geospatial data or an edit instruction input by the input / output unit. Rewriting means for rewriting the node information table by writing a set of the characteristic information and the device specifying information into the node information table. Between the data search devices, input a copy of each other's node information table via the input / output means,
When there is no set of the data feature information and the device specifying information in the copy input in the own node information table, the own node information table is written by writing the set to the own node information table by the rewriting means. Rewriting, between predetermined geographic information data search devices of different groups, input a copy of each other's node information table via the input / output means, and the data feature information in the copy input in its own node information table When there is no combination with the device specifying information, the combination is written in the own node information table by the rewriting means, thereby rewriting the own node information table.

According to one aspect of the present invention, a recording medium on which the geographic information data search program of the present invention is recorded is:
A recording medium recording a geographic information data search program for searching a geographic information database storing geospatial data, wherein a procedure for inputting external data including search conditions, and data feature information indicating characteristics of the geospatial data By referring to the node information table that is associated with the device specifying information for specifying the geographic information data search device, the data feature information that satisfies the input search condition is searched, and the searched data feature is searched. A step of searching for the device specifying information corresponding to the information, and, if the searched device specifying information is not the device specifying information for specifying the own geographic information data searching device, the device specifying information is specified by the searched device specifying information. Transferring the search condition to the geographic information data search device.

Preferably, the recording medium on which the geographic information data search program of the present invention is recorded is a device in which the searched device specifying information is device specifying information for specifying the own geographic information data searching device. It is preferable to include a procedure for searching for geospatial data based on the search condition and a procedure for outputting data including a search result.

Preferably, the recording medium on which the geographic information data search program of the present invention is recorded includes a procedure for rewriting the geographic information database based on input geospatial data or editing instructions, It is preferable that the method further includes a step of rewriting the node information table by writing a set of information and device identification information in the node information table.

Preferably, the recording medium on which the geographic information data search program of the present invention is recorded includes a step of converting place name information inputted as a search condition into latitude / longitude information as a new search condition. desirable.

Preferably, the recording medium on which the node information exchange program of the present invention is recorded records a node information exchange program for exchanging node information tables provided in a plurality of geographic information data search devices connected to a network. A geographic information data search device, comprising: input / output means for inputting external data including search conditions and outputting data including search results; and data characteristic information indicating characteristics of geospatial data. And a node information table that associates the information with a device specifying information for specifying a geographic information data search device, and data characteristic information that satisfies the search condition input by the input / output means by referring to the node information table. And a node information search means for searching for device identification information corresponding to the searched data feature information. If the device specifying information searched by the node information searching means is not device specifying information for specifying the own geographic information data searching device, the geographic information data searching device specified by the searched device specifying information is A transfer unit for transferring the search condition; and, if the device specifying information searched by the node information searching unit is device specifying information for specifying the own geographic information data searching device, A data search unit for searching for spatial data, and rewriting the geographic information database based on geospatial data or an editing instruction input by the input / output unit, and comparing the data feature information and device identification information input by the input / output unit Rewriting means for rewriting the node information table by writing the set in the node information table. A step of grouping one or more geographic information data search devices, and a copy of each node information table between the geographic information data search devices in the group via the input / output means; A procedure for rewriting the self-node information table by writing the set to the self-node information table by the rewriting means when there is no set of the data feature information and the device identification information in the copy input in the table And between predetermined geographic information data search devices of different groups, input a copy of each other's node information table via the input / output means, and the data feature information in the copy input in its own node information table When there is no set with the device specifying information, the set is written in the own node information table by the rewriting means, thereby making the own node information table available. Rewriting the bull.

[0030]

Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a functional block diagram of a geographic information data search system according to an embodiment of the present invention.

Referring to FIG. 1, a geographic information data search system 1 includes a plurality of geographic information data search devices 10 having a geographic information database 20 for storing geospatial data and a node information exchange device 40 connected to each other via a network 30. are doing.

The geographic information data search device 10 includes an input / output unit 11, a node information table 12, a node information search unit 13, a transfer unit 14, and a data search unit 15.
, Rewriting means 16 and geographic information conversion means 17.

The input / output means 11 inputs external data including search conditions and outputs data including search results. The node information table 12 stores data feature information indicating features of geospatial data and device specifying information for specifying a geographic information data search device in association with each other. The node information search means 13 is configured to store the node information table 1
2 to search for data feature information that satisfies the search condition input by the input / output means 11,
The apparatus specifying information corresponding to the searched data characteristic information is searched. The transfer unit 14 is specified by the searched device specifying information when the device specifying information searched by the node information searching unit 13 is not device specifying information for specifying the own geographic information data searching device 10. The above search conditions are transferred to the geographic information data search device 10. When the device specifying information searched by the node information searching unit 13 is device specifying information for specifying the own geographic information data searching device 10, the data searching unit 15 searches the geospatial data based on the search condition. Search for. The rewriting means 16 rewrites the geographic information database 20 based on the geospatial data or the editing instruction input by the input / output means 11, and
The node information table 12 is rewritten by writing in the node information table 12 a set of the data feature information and the device specifying information that have been input by the above. The geographic information conversion means 17 converts the place name information input by the input / output means 11 as a search condition into latitude and longitude information as a new search condition.

The node information exchange device 40 includes a grouping means 41, an intra-group exchange means 42, and an inter-group exchange means 43. The above grouping means 4
1 groups one or more geographic information data search apparatuses 10. The intra-group exchange means 42 inputs a copy of each other's node information table 12 via the input / output means 11 between the geographic information data search apparatuses 10 in the group, and inputs the duplicates in the own node information table 12. If there is no set of the data feature information and the device specifying information in the copy, the rewriting means 16 writes the set in the own node information table 12 to rewrite the own node information table 12. The inter-group exchange means 43
Are predetermined geographic information data retrieval devices 1 of different groups.
0, a copy of each other's node information table 12 is input via the input / output means 11 and the own node information table 1
In the case where there is no set of the data feature information and the device specifying information in the copy input in the copy unit 2, the set is rewritten by the rewriting means 16.
By rewriting the self-node information table 12, the self-node information table 12 is rewritten.

That is, the geographic information data search device 10
Selects, from the contents of a search request from an external client, its own or another geographic information data search device 10 which may have geographic information data that matches the search request, and matches the search request with those geographic data. Information data search device 10
Transfer to Thus, the client knows the location of at least one of the plurality of geographic information data retrieval apparatuses 10 and can determine the characteristics of the geographic information data possessed by the other geographic information data retrieval apparatuses 10 by the client. It is possible to perform a search without knowing its location or its location in advance.

Each of the geographic information data retrieval devices 10
Information describing what kind of geographic information data oneself has (data characteristic information and device specifying information: hereinafter also referred to as catalog node information) is distributed to other geographic information data retrieval devices 10. The geographic information data search device 10 stores catalog node information distributed from another geographic information data search device 10 in the node information table 12. The geographic information data search device 10 selects the geographic information data search device 10 to which the search request is transferred by comparing the search request from the client with the catalog node information.

FIG. 2 is a diagram for explaining the restriction on registration of spatial data by designating a geographical range to the catalog service. In FIG. 2, geographic information data to be searched by each geographic information data search device does not overlap with each other.

The catalog node information includes attribute information describing a geographic range covered by the geographic information data of the corresponding geographic information data search device. The search request by the client also includes attribute information describing the geographic range.

In order to realize the geographic information data search system as described with reference to FIG. 1, the function of the catalog service is not limited to operating with only a single geographic information data search device. Not only each catalog service function exists on the data search device,
Further, it is desirable that the spatial data managed by the respective geographic information data search devices do not overlap with each other. That is, it is desirable that the catalog service can determine another catalog service that should process the search request from the search condition of the user. For that purpose, information about spatial data managed by another catalog service is required.

In order to satisfy such a request, each catalog service has information (catalog node information) indicating characteristics of spatial data managed by itself. To characterize the entire spatial data owned by the catalog service, list similar (or approximate) items in the attribute information between all the spatial data and specify them as numerical ranges or indicate them as keywords. is necessary. for that reason,
The catalog service determines conditions for certain attribute information of spatial data, and prevents registration of spatial data that does not satisfy the conditions. In other words, a certain restriction is set on the spatial data that can be managed for the catalog service. For example, a geographical range can be used as the restriction. The geographic range is to designate a specific area by latitude and longitude.

However, in practice, it is generally considered that a user uses a place name instead of latitude and longitude to specify a geographical range. Therefore, a latitude / longitude conversion service that converts a place name into the corresponding latitude and longitude can be used.

FIG. 3 is a diagram for explaining sharing of catalog node information. In order for a search to be performed by an arbitrary geographic information data search device and to be searched by a geographic information data search device having geographic information data matching the requested search condition, a geographic information data search system is required. Must be provided (shared) with the catalog node information of the same content. For that purpose, it is necessary to exchange catalog node information with each other. One catalog node information exchange service (Node Information eXcha
nger: hereinafter referred to as NIX)
e, and register, update,
Perform deletion and so on. This allows Catalog Service to always share the latest node information.

That is, by sharing the above-described catalog node information among the catalog services, it is possible to notify other catalog services of their existence. However, distributing catalog node information by broadcasting to all other catalog services as a method imposes a heavy load on the network, and has a problem in efficiency.

FIG. 4 is a diagram for explaining the catalog node information exchange service. The catalog node information exchange service (NIX) is a mechanism for distributing catalog node information managed by each catalog service itself to other catalog services.

The newly installed geographic information data search device needs to be registered in any one of a plurality of catalog node information exchange services existing on the network.
Registration is performed by submitting catalog node information of the geographic information data search device to a catalog node information exchange service. The catalog node information exchange service periodically provides catalog node information to a geographic information data search device registered therein. The timing of providing information can be arbitrarily changed. The number of geographic information data search devices that can be registered in one catalog node information exchange service may be one or plural.

FIG. 5 is a diagram for explaining grouping of a plurality of catalog node information exchange services (NIX). In FIG. 5, a plurality of catalog node information exchange services form a logical group. Furthermore, a tree structure topology is formed by gathering a plurality of these groups. Catalog node information is first shared within a group and then exchanged between groups.

The number of groups and the depth and width of the tree structure
Dynamic depending on the number of catalog services, the amount of catalog node information exchanged, and the permissible transmission delay time (the time from when catalog node information is registered to the catalog node information exchange service until it is shared by all catalog services) Shall be determined.

[0048] A plurality of node information exchange services form a group, which is the range when catalog node information is broadcast and distributed. Catalog node information is exchanged for each group,
Within the group, catalog node information is distributed by broadcast. The catalog node information generated within the group is broadcast and distributed to the catalog node information exchange service within the group, and the catalog node information exchange service within the group transmits the catalog node information to the catalog node information exchange service of another group. Is done. Exchange of catalog node information between two groups having a parent-child relationship is performed by one of the catalog node information exchange services in both groups as a representative.

When the location of the geographic information data search device and the characteristics of the geographic information data possessed are changed, the change of the catalog node information of the geographic information data search device is performed on the network through the catalog node information exchange service. Distributed to other geographic information data retrieval devices. When the geographic information data search device is abolished, the deletion of the catalog node information of the geographic information data search device is notified to other geographic information data search devices on the network through the catalog node information exchange service. The geographic information data search device notified of the deletion of the catalog node information deletes the corresponding catalog node information.

An arbitrary catalog node information exchange service holds a list of locations of node information exchange services in the upstream group, the group to which it belongs, and the downstream group. The geographic information data search device that has received the search request from the client compares the search request with information of a plurality of catalog nodes managed by itself, and determines the geographic information data search device to which the search request is to be transferred.

If there is no geographic information data search device to which the search request is transferred, the client is notified of the search request that the corresponding geographic information data search device does not exist.

When transferring the search request, the address of the client (terminal) (for example, network address)
Is attached to the search request and forwarded. The geographical information data search device that has received the transferred search request searches the search request and its own geographic information database, and transmits the search result directly to the client.

The client prepares a program dedicated to receiving the search result so as to receive the search result from the geographic information data search device, and waits until the search result is distributed from the geographic information data search device.

Alternatively, instead of transmitting the search result directly to the client, the search result is returned to the geographic information data search device that is the transfer source, and the geographic information data search device that receives the search result is as if to the client. The search result may be returned as if the user performed the search.

FIG. 6 is a diagram for explaining that the conventional problem has been solved by the present invention. In FIG. 6, geographic information data search devices A to F each have geographic information data and exist on a network. Since the client C1 knows that the geographic information data satisfying the search request exists in the geographic information database of the geographic information data search device B, the client C1 submits the search request directly to the geographic information data search device B, and Search results can be obtained. This is the same as before. Further, the client C2 does not know that the geographic information data satisfying the search request exists in the geographic information database of the geographic information search device E, but submits the search request to the geographic information data search device C. Then, since the geographic information data search device C knows that the geographic information data search device E satisfies the search request, the search request is sent from the geographic information data search device C to the geographic information data search device E. The geographic information data that is transferred and satisfies the search request from the geographic information data search device E is stored in the geographic information data search device E.
(Or directly) to the client C2.

FIG. 7 is a diagram showing a network structure as a geographic information data search system. In FIG.
(A) is a physically fixed network configuration actually connected, (b) is a tree configuration topology in which the network of (a) is formed by five logical groups, and (c) Is that the network of (a) forms a tree topology with nine logical groups, and (d)
In the figure, the network of (a) forms a tree-structured topology by 13 logical groups. Each circled number is a geographic information data search device in which a catalog node information exchange service is arranged.

In a network having such a configuration,
Simulations were performed on the time and traffic required for catalog node information to be transmitted between all catalog node information exchange services. As a condition of the simulation, it is assumed that the distance between adjacent catalog node information exchange services in the physical network is 1, and each catalog node information exchange service transmits catalog node information to a plurality of catalog node information exchange services almost simultaneously. It is assumed that transmission is possible, and the traffic volume when one catalog node information is transmitted between two catalog node information exchange services is assumed to be one.

As a result, in the case of FIG. 7B, the transmission time is 11247 (ms: millisecond) and the traffic volume is 33 (pieces). In the case of FIG. 7C, the transmission time is 15207 (m
s), the call volume becomes 29 (pieces), and in the case of FIG.
The transmission time was 14623 (ms) and the call volume was 24 (pieces). From this, as the number of groups increases,
The call volume was found to decrease. However, the transmission time was unexpected for the groups 9 and 13. This is because a path between adjacent catalog node information exchange services in a logical network of catalog node information exchange services has a distance of 1 in a physical network.
It is considered that the above route causes a delay in transmission time.

The network of the catalog node information exchange service has a characteristic that its scale increases with time. That is, as the number of catalog services increases, the load on the server (geographic information data search device) of the catalog node information exchange service increases, and the quality of the services may be degraded. Then, the following operations (M1) to (M3) are newly added to the server of the catalog node information exchange service, and the network topology of the catalog node information exchange service is changed autonomously, so that each catalog node information exchange service is changed. Server load was minimized, and the time (cost) required for node information support was minimized. (M1) Install a new catalog node information exchange service server. (M2) Move the catalog node information exchange service server to another server. (M3) A catalog service close to a network is placed under its own management.

The server of the catalog node information exchange service changes its network topology by the following procedures (P1) to (P3). These procedures are performed when a new catalog service is established or abolished. (P1) Division of catalog node information exchange service (P2) Reconfiguration of catalog service (P3) Movement of catalog node information exchange service The above (P1) division of catalog node information exchange service requires a new catalog node information exchange service server. Make it appear on the network. The condition for calling this procedure is that the number of catalog services registered in a server of a certain catalog node information exchange service exceeds a certain value. As the server of the new catalog node information exchange service, the catalog service having the longest network distance among the catalog services managed by the server of the previous catalog node information exchange service is selected. FIG. 8 shows this state.

(P2) The reconfiguration of the catalog service is performed in such a manner that the management right of the catalog service installed near the server of a certain catalog node information exchange service is changed to that of another catalog node information exchange service managing the catalog service. Take over from server and put it under your control. When this procedure is executed, the catalog node information exchange service server obtains a list of catalog services from the neighboring catalog node information exchange service server. This list records the distance between the location of each catalog service and the managed catalog node information exchange service. The server of the catalog node information exchange service that has executed this procedure measures the distance from the catalog service in the list. If the measured result is shorter than the one in the list, an application for transfer of the management right is made to the managing server of the catalog node information exchange service. Repeat this to put the nearby catalog service under your control. FIG. 9 shows this state.

The (P3) movement of the catalog node information exchange service is a procedure performed when the server of the catalog node information exchange service is moved to another place. Specifically, the server of the catalog node information exchange service is moved by another catalog service, the information of the catalog service being managed is moved, and the server of the original catalog node information exchange service is terminated. The above (P
3) The location where the server of the catalog node information exchange service moves when the catalog node information exchange service moves is
The catalog service that has the smallest average network distance among the catalog services under management is selected. FIG. 10 shows this state.

The number of catalog services that can be managed is defined in advance in the server of the catalog node information exchange service, and a process as shown in FIG. 11 is executed at a timing when catalog services exceeding the number are registered. As a result, the server of the catalog node information exchange service and the network formed by the catalog service can maintain an optimal tree structure topology for distributing catalog node information. The network formed by these procedures has the following characteristics (C
1) and (C2). (C1) The network distance between the catalog node information exchange service server and the catalog service is shorter than the distance between any two catalog node information exchange service servers. (C2) The number of catalog node information exchange service servers is smaller than the number of catalog services registered in any one catalog node information exchange service server.

The catalog node information exchange service server simulates (evaluates) the catalog node information exchange service network formed by performing the above-described procedure when the catalog node information exchange service network dynamically changes. This was performed from the viewpoint of the cost of the procedure and the distribution time until one catalog node information was distributed to all catalog services.

Specifically, the simulation was performed on a two-dimensional virtual network. The network distance between the machines was assumed to be the Euclidean distance on the virtual network. Also, it is assumed that the data to be communicated is very small with respect to the bandwidth of the communication network. Thus, the distance between two machines on a virtual network is similar to the round trip time in a real network.

First, a 400 × 600 two-dimensional plane was assumed to be a virtual network, and data sets were created when the number of catalog services arranged therein was 30, 60, and 90, respectively.

Next, the contents of one data set are read,
Catalog services were arranged one by one. At this time, the communication cost required to execute the procedure of the catalog node information exchange service server was measured and accumulated.

After arranging all the catalog services, an attempt was made to transfer catalog node information from each catalog service, and the time until the transfer was completed to all the catalog services was measured.

The number of catalog services managed by the catalog node information exchange service server was given as a parameter given in the simulation. “Limit of CatalogServices” in FIG. 12 corresponds to this. If this number is exceeded, the catalog node information exchange service server divides the procedure (P1) catalog node information exchange service. Therefore, when there is no limit, the server of the catalog node information exchange service does not have a server of the new catalog node information exchange service, and only one server of the catalog node information exchange service exists on the network.

The method of distributing catalog node information is performed between the servers of the catalog node information exchange service in a binary tree topology with the server of the catalog node information exchange service receiving the node information from the catalog service as a root. A star topology is performed between the information exchange service server and the catalog service, centering on the catalog node information exchange service server. Note that the number of connections that can be simultaneously established in communication between machines is one.

FIG. 12 shows the result of the simulation. Outputs of the virtual network in each data set are shown in FIGS. In FIG. 13, the number of catalog services per server of the catalog node information exchange service is indicated by 7 in the upper left output screen.
The number of vehicles is 10 at the upper right, 15 at the lower left, and unlimited at the lower right.

In FIG. 14, the number of catalog services per server of the catalog node information exchange service is 8 on the upper left output screen, 15 on the upper right, and 30 on the lower left.
The platform and lower right are unlimited.

In FIG. 15, the number of catalog services per server of the catalog node information exchange service is 11 on the upper left output screen, 23 on the upper right, and 4 on the lower left.
5 cars, bottom right is unlimited.

The simulation was performed by giving a limitation to the catalog service managed by the catalog node information exchange service server. The number of catalog node information exchange service servers existing on the network for each data set is limited to “limit of CatalogServices”. "Is inversely proportional to the value of.

FIG. 12 shows that distribution of catalog node information by a plurality of catalog node information exchange service servers for any of the three types of data sets is performed by a single catalog node information exchange service server. It was found that the distribution time of catalog node information was short.

In the comparison within the data set, when the number of servers of the catalog node information exchange service is relatively small, the average distance between the catalog node information exchange service server and the catalog service is long, and the catalog node information exchange service is long. The number of catalog services managed by one exchange service server is large. The time required for distributing the catalog node information is the following time (T1) to (T1).
5). (T1) Transmission time of node information from the server of the catalog node information exchange service to the catalog service (T2) Wait time until transmission of catalog node information between servers of the catalog node information exchange service (T3) Exchange of catalog node information Transmission time of catalog node information between service servers (T4) Waiting time for transmitting node information from catalog server information exchange service server to catalog service (T5) Catalog node information exchange service server to catalog service Therefore, if there is a large number of catalog services managed by one catalog node information exchange service server, the waiting time until catalog node information is transmitted from the catalog node information exchange service server to the catalog service But it becomes a bottleneck.

The communication cost (“time of metamorphosis” in FIG. 12) when the network of the catalog node information exchange service dynamically changes increases as the number of servers of the catalog node information exchange service decreases. ing. This is because the server of the catalog node information exchange service communicates a lot with the server of the catalog node information exchange service at a long distance during the reconfiguration of the catalog service (P2). Conversely, when the number of servers for the catalog node information exchange service is large,
The server of the catalog node information exchange service communicates with the server of the short-range catalog node information exchange service in the procedure (P2) reconfiguration of the catalog service, and can be located at a short distance and managed. Since the procedure is terminated when the catalog service cannot be found, the communication cost is small.

As described above, the present invention is applied to a plurality of geographic information data management server machines (geographic information data search devices) which are distributed on an electronically integrated network. When a user (client) participating in the process obtains geographic information data, the geographic information data search device receives a geographic information data search request from the client, and the geographic information data search device has Comparing the information about the other geographic information data search device with the search request of the client, and calculating, as a result of the comparison, which geographic information data search device has the geographic information data requested by the client. Transmitting the geographic information data to the client by the selected geographic information data search device; In order to share each other's information (catalog node information) between the data search apparatuses, a step of registering each node information in the node information exchange service, and a step of registering the node information received by the node information exchange service with the respective geographical information. A geographic information data search method, a geographic information data search device, or a node information exchange device, which includes a step of distributing the information to an information data search device.

Further, in the geographic information data search device, receiving a search request from the client;
Comparing the search request received from the client with the geographic information data held by the geographic information data search device; and having the geographic information data search device correspond to the search request received from the client. Transmitting the geographic information data to the client; comparing the search request received from the client with the node information of the geographic information data search device; and applying the search request received from the client. Transmitting the search request to the geographic information data search device described in the node information.

Further, in the node information exchange service, a step of registering the node information in the node information exchange service from the geographic information data search device, and transmitting the registered node information to another node information exchange service. Registering the node information with the geographic information data search device excluding the node information transmission source; forming a group with another node information exchange service; The present invention realizes a recording medium in which a program for a node information exchange service including a process of exchanging information is recorded.

The geographic information data retrieval device or the node information exchange device to which the present invention is applied is not limited to the above-described embodiment as long as its function is executed, and may be a single device. Needless to say, the system may be a system including a plurality of devices or an integrated device, or may be a system in which processing is performed via a network such as a LAN or a WAN.

Further, a CPU connected to the bus, a memory such as a ROM or a RAM, an input device, an output device, an external recording device,
The present invention can also be realized by a system including a medium driving device, a portable recording medium, and a network connection device. That is, a ROM or RAM memory that records software program codes for realizing the system of the above-described embodiment,
By supplying an external recording device and a portable recording medium to a system or a device, and reading and executing the program code by a computer of the system or the device,
Needless to say, this is achieved.

In this case, the program code itself read from the recording medium implements the novel function of the present invention, and the portable recording medium or the like on which the program code is recorded constitutes the present invention. .

Examples of portable recording media for supplying program codes include floppy disks, hard disks, optical disks, magneto-optical disks, and CD-ROs.
M, CD-R, DVD-ROM, DVD-RAM, magnetic tape, nonvolatile memory card, ROM card, various types of data recorded via a network connection device (in other words, a communication line) such as e-mail and personal computer communication. A recording medium or the like can be used.

Further, the functions of the above-described embodiment are realized by the computer executing the program code read out on the memory, and the operating system running on the computer based on the instruction of the program code.
Perform part or all of the actual processing, and the functions of the above-described embodiments are also realized by the processing.

Further, after the program code read from the portable recording medium is written into the memory provided in the function expansion board inserted into the computer or the function expansion unit connected to the computer, the program code is transmitted to the instruction of the program code. Based on this, the CPU or the like provided in the function expansion board or function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments can also be realized by the processing.

That is, the present invention is not limited to the above-described embodiment, and can take various configurations or shapes without departing from the gist of the present invention.

[0088]

As described above, by distributing the node information of the node information exchange service to the geographic information data search device according to the present invention, the node information describing the attribute information of the geographic information data search device is transmitted to the geographic information data search device. By being shared, it is possible to determine to transfer the search request to a geographic information data search device that may have geographic information data that matches the search request.

As a result, if the client knows the location of at least one geographic information data search device, it can indirectly access all the geographic information data search devices.

As a result, it is possible to provide a geographic information data search device capable of using node information, a device having a function of a node information exchange service for distributing node information, and a recording medium recording these programs. .

[Brief description of the drawings]

FIG. 1 is a functional block diagram of a geographic information data search system according to an embodiment of the present invention.

FIG. 2 is a diagram for explaining a restriction on registration of spatial data by designating a geographical range to a catalog service;

FIG. 3 is a diagram for describing sharing of catalog node information.

FIG. 4 is a diagram for explaining a catalog node information exchange service.

FIG. 5 shows a plurality of catalog node information exchange services (NI
It is a figure for explaining grouping of X).

FIG. 6 is a diagram for explaining that a conventional problem has been solved by the present invention.

FIG. 7 is a diagram showing a network structure as a geographic information data search system.

FIG. 8 is a diagram showing a state of division of a catalog node information exchange service.

FIG. 9 is a diagram showing a state of reconfiguration of a catalog service.

FIG. 10 is a diagram showing a state of movement of a catalog node information exchange service.

FIG. 11 is a diagram showing a timing at which a catalog service is registered.

FIG. 12 is a diagram showing a result of a simulation.

FIG. 13 is a diagram (part 1) in which a result of a simulation is output.

FIG. 14 is a diagram (part 2) in which the result of the simulation is output.

FIG. 15 is a diagram (part 3) in which the result of the simulation is output.

FIG. 16 is a diagram for explaining generation of a catalog entry instance.

FIG. 17 is a diagram for explaining a catalog service.

FIG. 18 is a diagram for explaining a conventional search and its problems.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 geographic information data search system 10 geographic information data search device 11 input / output means 12 node information table 13 node information search means 14 transfer means 15 data search means 16 rewriting means 17 geographic information conversion means 20 geographic information database 30 network 40 node information exchange Apparatus 41 Grouping means 42 Intra-group exchange means 43 Inter-group exchange means

Continuing from the front page (72) Inventor Hiroki Hirara 1 Chihara, Nishihara-cho, Nakagami-gun, Okinawa Prefecture, University of the Ryukyus (72) Hayao 1 Okinawa, Nishihara-cho, Nakagami-gun, Okinawa F-term, University of the Ryukyus F-term (reference) 5B075 KK02 KK13 KK33 NK02 NK54 PP01 UU14 5B089 GA11 GB03 JA12 KA01 KC15 KC44

Claims (16)

[Claims] 1. A geographic information data search device having a geographic information database storing geospatial data, comprising: input / output means for inputting external data including search conditions and outputting data including search results; A node information table in which data characteristic information indicating data characteristics is associated with device identification information for identifying a geographic information data search device; and Node information searching means for searching for data feature information satisfying the search condition and searching for device specifying information corresponding to the searched data feature information; If it is not device specifying information for specifying the data search device, the geographic information specified by the searched device specifying information is used. To the data retrieval device, spatial data retrieval apparatus comprising: a transfer means for transferring the search condition. 2. The method according to claim 1, wherein the device specifying information searched by the node information searching means is device specifying information for specifying a self-geographic information data searching device, and geospatial data is searched based on the search condition. The geographic information data search device according to claim 1, further comprising a data search unit that performs the search. And rewriting the geographic information database based on geospatial data or an editing instruction input by the input / output means, and sets a set of data characteristic information and device identification information input by the input / output means. 2. A rewriting means for rewriting the node information table by writing to the node information table.
Or the geographic information data search device according to 2. 4. The apparatus according to claim 1, further comprising geographic information conversion means for converting place name information input by said input / output means as a search condition into latitude / longitude information as a new search condition. 2. The geographic information data search device according to claim 1. 5. A node information exchange device in which a plurality of geographic information data retrieval devices each including a geographic information database storing geospatial data are connected to a network connected to each other, wherein the geographic information data retrieval device includes a search condition. Input / output means for inputting data from the outside and outputting data including a search result, and associating data feature information indicating features of geospatial data with device identification information for identifying a geographic information data search device. By referring to the node information table and the node information table, data characteristic information that satisfies the search condition input by the input / output unit is searched, and device identification information corresponding to the searched data characteristic information is searched. Node information searching means for searching, and device identification information searched for by the node information searching means. If it is not the device identification information for identifying a
A transfer unit that transfers the search condition to the geographic information data search device specified by the searched device specifying information; and a device specifying information searched by the node information search unit transmits the own geographic information data search device. When the device identification information is for specifying, the data search means for searching geospatial data based on the search condition, and the geographic information database based on the geospatial data or edit instruction input by the input / output means. Rewriting means for rewriting the node information table by writing a set of data characteristic information and device identification information input by the input / output means to the node information table; A node information table between a grouping means for grouping the search devices and a geographic information data search device in the group; Replication inputted via the said input output means,
When there is no set of the data feature information and the device identification information in the copy input in the own node information table, the set is written to the own node information table by the rewriting means, thereby making the own node information table available. Between the intra-group rewriting means to be rewritten and a predetermined geographic information data retrieval device of a different group,
A duplicate of each other's node information table is input via the input / output means, and if there is no set of the data feature information and the device identification information in the duplicate input in the own node information table, the set is A node information exchange device comprising: an inter-group exchange unit that rewrites the own node information table by writing the own node information table by rewriting unit. 6. A geographic information data search system in which a plurality of geographic information data search devices each including a geographic information database storing geospatial data and a node information exchange device are connected to each other via a network. Input / output means for inputting external data including search conditions and outputting data including search results, data feature information indicating features of geospatial data, and device identification for identifying a geographic information data search device By referring to the node information table in which information is associated with the node information table, data characteristic information that satisfies the search condition input by the input / output unit is searched, and the data characteristic information corresponding to the searched data characteristic information is searched. Node information search means for searching for device identification information to be performed, and device identification searched by the node information search means Transfer means for transferring the search condition to the geographic information data search device specified by the searched device identification information, if the information is not device identification information for identifying the own geographic information data search device; When the device specifying information searched by the node information searching means is device specifying information for specifying the own geographic information data searching device, data searching means for searching geospatial data based on the search condition; By rewriting the geographic information database based on geospatial data or editing instructions input by the input / output means, and writing a set of data characteristic information and device identification information input by the input / output means to the node information table, Rewriting means for rewriting the node information table, wherein the node information exchange device includes one or more of the geographic information data search devices. And grouping means for looping, between spatial data retrieval apparatus in the group, via the said input output means replication of each other node information table type,
When there is no set of the data feature information and the device identification information in the copy input in the own node information table, the set is written to the own node information table by the rewriting means, thereby changing the own node information table. Between the intra-group exchange means to be rewritten and the predetermined group of geographic information data retrieval devices of different groups,
If a copy of each other's node information table is input via the input / output means, and there is no set of the data feature information and device identification information in the copy input in the own node information table, the set is A geographic information data search system comprising: an inter-group exchange unit that rewrites the own node information table by writing to the own node information table by a rewriting unit. 7. A geographic information data search method for searching a geographic information database storing geospatial data, wherein data from outside including search conditions is input, and data feature information and geographic information data indicating characteristics of the geospatial data. By referencing the node information table associated with the device specifying information for specifying the search device, searching for data feature information that satisfies the input search condition,
Searching for the device specifying information corresponding to the searched data characteristic information, if the searched device specifying information is not the device specifying information for specifying the own geographic information data searching device, the searched device specifying information A geographic information data search method characterized by transferring the search condition to a geographic information data search device specified by: 8. When the searched device specifying information is device specifying information for specifying a self-geographic information data searching device, geospatial data is searched based on the search condition, and data including a search result is provided. 10. The geographic information data search method according to claim 7, wherein 9. The node information table is rewritten by rewriting the geographic information database based on the input geospatial data or editing instruction, and writing a set of the input data characteristic information and the device specifying information in the node information table. 9. The method for retrieving geographic information data according to claim 7, wherein rewriting is performed. 10. The geographic information data search method according to claim 7, wherein the place name information input as a search condition is converted into latitude / longitude information as a new search condition. 11. A node information exchange method for exchanging node information tables provided in a plurality of geographic information data search apparatuses connected to a network, wherein the geographic information data search apparatus inputs external data including search conditions. An input / output means for outputting data including a search result; a node information table in which data characteristic information indicating characteristics of geospatial data is associated with device identification information for identifying a geographic information data search device; A node information search unit that searches for data feature information that satisfies the search condition input by the input / output unit by referring to the node information table, and searches for device identification information corresponding to the searched data feature information; The device identification information retrieved by the node information retrieval means is used to identify a device for retrieving its own geographic information data. If it is not the information,
A transfer unit that transfers the search condition to the geographic information data search device specified by the searched device specifying information; and a device specifying information searched by the node information search unit transmits the own geographic information data search device. When the device identification information is for specifying, the data search means for searching geospatial data based on the search condition, and the geographic information database based on the geospatial data or edit instruction input by the input / output means. Rewriting means for rewriting the node information table by writing a set of data characteristic information and device identification information input by the input / output means to the node information table; Search devices are grouped, and a copy of each node information table is copied between the geographic information data search devices in the group by the input / output method. Enter through the,
When there is no set of the data feature information and the device identification information in the copy input in the own node information table, the set is written to the own node information table by the rewriting means, thereby changing the own node information table. Rewriting, between predetermined groups of geographic data retrieval devices of different groups,
If a copy of each other's node information table is input via the input / output means, and there is no set of the data feature information and device identification information in the copy input in the own node information table, the set is A node information exchange method characterized by rewriting the own node information table by writing to the own node information table by rewriting means. 12. A recording medium storing a geographic information data search program for searching a geographic information database storing geospatial data, wherein a procedure for inputting external data including a search condition and a feature of the geospatial data are shown. By referring to the node information table associated with the data feature information and the device specifying information for specifying the geographic information data search device, to search for data feature information that satisfies the input search condition,
A step of searching for the device specifying information corresponding to the searched data characteristic information; and, if the searched device specifying information is not the device specifying information for specifying the own geographic information data searching device, the searched device Transferring a search condition to a geographic information data search device specified by the specific information. 13. A method for searching geospatial data based on the search condition, wherein the searched device specifying information is device specifying information for specifying a self-geographic information data searching device. 13. A recording medium recording the geographic information data search program according to claim 12, further comprising a step of outputting data including the data. 14. A method for rewriting the geographic information database based on input geospatial data or an editing instruction, and writing a set of input data feature information and device identification information in the node information table, thereby obtaining the node information. 14. A recording medium recording the geographic information data search program according to claim 12, further comprising a step of rewriting the information table. 15. The method according to claim 12, further comprising a step of converting place name information input as a search condition into latitude / longitude information as a new search condition.
Recording medium on which the geographic information data search program described in the item is recorded. 16. A recording medium recording a node information exchange program for exchanging node information tables provided in a plurality of geographic information data search devices connected to each other on a network, wherein the geographic information data search device includes an external device including search conditions. Input / output means for inputting data from the server and outputting data including a search result, and a node in which data feature information indicating the feature of geospatial data is associated with device identification information for identifying a geographic information data search device. By referring to the information table and the node information table, data feature information that satisfies the search condition input by the input / output unit is searched, and device identification information corresponding to the searched data feature information is searched. A node information retrieving unit, and a device identification information retrieved by the node information retrieving unit. If it is not the device identification information for identifying a
A transfer unit that transfers the search condition to the geographic information data search device specified by the searched device specifying information; and a device specifying information searched by the node information search unit transmits the own geographic information data search device. When the device identification information is for specifying, the data search means for searching geospatial data based on the search condition, and the geographic information database based on the geospatial data or edit instruction input by the input / output means. Rewriting means for rewriting the node information table by writing a set of data characteristic information and device identification information input by the input / output means to the node information table; The procedure for grouping the search devices and the duplication of each other's node information table between the geographic information data search devices in the group are performed. Enter through the output means,
When there is no set of the data feature information and the device identification information in the copy input in the own node information table, the set is written to the own node information table by the rewriting means, thereby changing the own node information table. Between the rewriting procedure and a predetermined group of geographic information data retrieval devices of different groups,
If a copy of each other's node information table is input via the input / output means, and there is no set of the data feature information and device identification information in the copy input in the own node information table, the set is Rewriting the self-node information table by writing the self-node information table by rewriting means.