Abstract:
Provided is a system or the like capable of allowing a navigation-client to efficiently use a route search result by a navigation server, while accepting the existence of difference between map data used by each of the navigation server and the navigation-client. By having a common description such as coordinate values, it is able to make the navigation-client  200  efficiently use the route search result by the navigation server  100 , while accepting the existence of difference of map data used by each of the navigation server  100  and the navigation-client  200.

Description:
TECHNICAL FIELD 
     The present invention relates to a navigation technology which guides a user to a designated position. 
     BACKGROUND ART 
     There has been proposed a technical method to have a navigation-client reproduce a route searched by a navigation server according to a communication between the navigation server and the navigation-client mounted in a vehicle or the like (refer to Patent Document 1). 
     In particular, link identification information for identifying a link constituting a part of a server route searched by the navigation server is transmitted to the navigation-client. According to this, information of coordinate rows of latitude and longitude expressing the link associated with the link identification information is read out from a storage unit, and a client route is searched and output based on the coordinate row information by the navigation-client. On such occasion, a client route which completely or almost completely matches the server route can be searched by performing interpolation processing for connecting discontinuous portions which cannot be supplemented only by the link identification information sent from the navigation server. 
     PRIOR ART DOCUMENTS 
     Patent Documents 
     Patent Document 1: Japanese patent application laid-open publication No. 2009-019924 
     SUMMARY OF THE INVENTION 
     Problems to be Solved by the Invention 
     However, there is a possibility that a client route extremely diverged from the server route is searched in a case where a server map data used by the navigation server and a client map data used by the navigation-client do not exactly match. The difference between the map data includes, for example, a difference of a format of describing method or the like of the link identification information as well as a difference of a range of the link covered. 
     In this regard, it is an object of the present invention to provide a system or the like capable of making the navigation-client to efficiently use a route search result by the navigation server, while accepting the existence of difference between map data used by each of the navigation server and the navigation-client. 
     Means for Solving the Problem 
     In order to solve the above problem, the navigation system of the present invention is a navigation system composed of a navigation server and a navigation-client, the navigation server comprising: a server storage unit configured to store a server map in which each location is described by a coordinate value including latitude and longitude and a link for route calculation is described by a group of coordinate values; a first server arithmetic processing element configured to receive designated location point information from the navigation-client, and to recognize each of two designated location points based on the designated location point information, and then by using a server map, to search for one or a plurality of server routes constituted by a plurality of links connecting the two designated location points; and a second server arithmetic processing element configured to transmit route information in which an arrangement manner of the server route searched by the first server arithmetic processing element is expressed by coordinated values, addressed to the navigation-client, the navigation-client comprising: a client storage unit configured to store a client map in which each location point is described by a coordinate value including latitude and longitude; an image output device; a first client arithmetic processing element configured to transmit the designated location point information to the navigation server; and a second client arithmetic processing element configured to receive the route information from the navigation server, and to output a client route superimposed on the client map to the image output device, the client route being a route having an arrangement manner in the client map which matches the arrangement manner expressed by the coordinate values included in the route information. 
     It is preferable that a travelling cost of a user of the navigation-client in each link is described by a designated map, the designated map being one of the server map and the client map, and a first designated arithmetic processing element, which is one of the first server arithmetic processing element and the first client arithmetic processing element that uses the designated map, is configured to preferentially recognize a location point, which is peripheral to a reference location point, the reference location point being at least one of a departure location point and a destination location point of the user, and which has a relatively low travelling cost of the user along a vicinity route constituted by one or a plurality of links connecting the reference location point and the location point, as at least one of the two designated location points. 
     It is preferable that the first designated arithmetic processing element is configured to search the server route which makes the user move in a direction which is relatively easier to move out from a designated area in which the designated location point is included or move into the designated area in a two-way traffic road, in a case where an exit or an entrance of the designated area is in contact with the two-way traffic road. 
     It is preferable that the client storage unit is configured to store a plurality of the client maps of different types and the second client arithmetic processing element is configured to selectively display the client map of the type designated by the user on the image output device. 
     The navigation server for solving the problem is a navigation server constituting the navigation system and characterized in comprising the server storage unit, the first server arithmetic processing element, and the second server arithmetic processing element. 
     The navigation-client for solving the problem is a navigation-client constituting the navigation system and characterized in comprising the client storage unit, the image output device, the first client arithmetic processing element, and the second client arithmetic processing element. 
     A navigation method of the present invention for solving the problem is a navigation method performed by a navigation server comprising a server storage unit configured to store a server map in which each location point is described by a coordinate value including latitude and longitude and in which a link for route calculation is described by a group of coordinate values, and by a navigation-client comprising a client storage unit configured to store a client map in which each location point is described by a coordinate value including latitude and longitude, and an image output device, the navigation method comprising: a step of the navigation-client transmitting designated location point information to the navigation server; a step of the navigation server recognizing each of two designated location points based on the designated location point information, and then searching one or a plurality of server routes constituted by a plurality of links connecting the two designated location points using the server map; a step of the navigation server transmitting route information expressing an arrangement manner of the server route by coordinate values, addressed to the navigation-client; and a step of the navigation-client making the image output device to output a client route superimposed on the client map, the client route being a route having an arrangement manner in the client map which matches the arrangement manner expressed by the coordinate values included in the route information. 
     It is preferable that a travelling cost of a user of the navigation-client in each link is described by a designated map, the designated map being one of the server map and the client map, and comprising a step of a designated device which is among the navigation server and the navigation-client that uses the designated map, preferentially recognizing a location point, which is peripheral to a reference location point, the reference location point being at least one of a departure location point and a destination location point of the user, and which has a relatively low travelling cost of the user along a vicinity route constituted by one or a plurality of links connecting the reference location point and the location point, as at least one of the two designated location points. 
     It is preferable to comprise a step of the designated device searching the server route which makes the user move in a direction which is relatively easier to move out from a designated area in which the designated location point is included or move into the designated area in a two-way traffic road, in a case where an exit or an entrance of the designated area is in contact with the two-way traffic road. 
     Here, an element of the present invention “recognizes” an information means to execute all kinds of information processing in order to prepare the information for other information processing such as the element receiving the information, search or reading out the information from a database or a memory, performing a designated arithmetic processing to basic information received or detected or the like to calculate, measure, estimate, set, determine, search, forecast etc., the information, actualizing the information by decoding a packet received or the like, furthermore, storing the information calculated or the like in the memory, or the like. 
     Effect of the Invention 
     According to the navigation system and the navigation method of the present invention, an arrangement manner f(p) of a position, posture, and a shape or the like of a server route (route  1 ) (dashed line) shown in the upper part of  FIG. 6A , is extracted as route information as shown in the lower part of  FIG. 6A  in a form expressed by coordinate values for specifying each location point of a server map (map  1 ) (refer to  FIG. 2 /STEP  120 ). 
     As a result of reproducing the arrangement manner f(p) of the server route (route  1 ) shown in the upper part of  FIG. 6B  in a client map (map  2 ) in which each location point is described by coordinate values as shown in the lower part of  FIG. 6B , a client route (route  2 , shown in two-dotted line) is output. That is, image data of the server route (route  1 ) and image data of the client map (map  2 ) are superimposed so as to match their position, posture, and shape by the coordinate values which are the common description portions of both maps (map  1 ) and (map  2 ), and displayed on an output device  202 . 
     As such, by the existence of the common description such as the coordinate values, it is able to make a navigation-client  200  effectively use the route search result by a navigation server  100  while allowing the existence of difference of map data used by each of the navigation server  100  and the navigation-client  200 . That is, even if the server map and the client map differ in the format of description method or the like of the link identification information of a common link, it is able to make the navigation-client  200  efficiently use the route search result by the navigation server  100 . 
     Moreover, a departure point p 1  is not itself recognized as a first designated location point q 1  which is the starting point of the server route, but a location point appropriate in view of travelling cost in an initial stage (a stage of travelling a vicinity route) of the user directing from the departure point p 1  to a destination point p 2 , can be recognized as the first designated location point q 1  (refer to  FIG. 3A ,  FIG. 3B ). 
     Moreover, the destination point p 2  is not itself recognized as a second designated location point q 2  which is the terminal point of the server route, but a location point appropriate in view of the travelling cost in an ending stage (a stage of travelling a vicinity route) of the user directing from the departure point p 1  to the destination point p 2 , can be recognized as the second designated location point q 2  (refer to  FIG. 4A ,  FIG. 4B ). 
     Therefore, it is able to smoothly guide the user to the destination point p 2  according to the client route as a result of reproducing the server route in the navigation-client  200 . 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a configuration diagram of a navigation system of an embodiment of the present invention. 
         FIG. 2  is a view explaining the procedure of the navigation method of the embodiment of the present invention. 
         FIG. 3A  and  FIG. 3B  are explanation views related to a method for setting a first designated location point of a server route. 
         FIG. 4A  and  FIG. 4B  are explanation views related to a method of setting a second designated location point of the server route. 
         FIG. 5A  and  FIG. 5B  are explanation views related to a searching method of a server route in a vicinity of the designated location point. 
         FIG. 6A  and  FIG. 6B  are explanation views related to a reproduction method of a client route based on the server route. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     (Configuration of the Navigation System) 
     The navigation system illustrated in  FIG. 1  is composed of a navigation server  100  and a navigation-client  200 . Among a plurality of navigation-clients  200 , at least a part of the navigation-clients  200  may function as the navigation server  100  temporary or constantly. 
     The navigation server  100  includes a server storage unit  104 , a first server arithmetic processing element  110 , and a second server arithmetic processing element  120 . The navigation server  100  has communication function with the navigation-client  200  via a network, and is configured of one or a plurality of server computers. Internet, telephone lines network, or communication network using satellite broadcasting can be used as the network. 
     The server storing unit  104  is configured to store a server map in which each location point is described by latitude and longitude. In the server map, a link connecting two location points (traffic intersections or the like) a part from each other is described by a group of coordinate values or coordinate rows expressing a plurality of location points on the link. At least a part of the link may be described in relation to link identification information for identifying the link or a type of the road or the like constituted by the link. Moreover, a location range of a park, river, premises of facilities are described by coordinate rows expressing a plurality of location points on an outline of the range or a closed curve. Each range may be described in relation to a type of the object located in the range. 
     The first server arithmetic processing element  110  is configured to receive designated location point information from the navigation-client  200 , and to recognize each of two designated location points based on the designated location point information. The first server arithmetic processing element  110  is configured to search one or a plurality of server routes composed of a plurality of links connecting the two designated location points by using the server map. 
     The second server arithmetic processing element  120  is configured to generate a route information in which an arrangement manner of the server route searched by the first arithmetic processing element  110  is expressed by coordinate values, and then transmit the route information to the navigation-client  200 . 
     The first server arithmetic processing element  110  and the second server arithmetic processing element  120  are each configured by a programmable computer. An element of the present invention executes information arithmetic processing in charge means that the element reads out a program from the memory and is programmed to execute the information arithmetic processing in charge according to the program. The program is downloaded to the navigation server  100  through a network or installed through a storage medium. Each of the first server arithmetic processing element  110  and the second server arithmetic processing element  120  may be configured of a hardware, which is in part or in total physically independent and separate. 
     The navigation-client  200  includes an input unit  201 , an output unit  202 , a client storage unit  204 , a first client arithmetic processing element  210 , and a second client arithmetic processing element  220 . The navigation-client  200  may be configured by a portable device, or may be configured as a device temporarily or constantly installed in a vehicle. 
     The input unit  201  is configured by a push-button type or touch-screen type interface, and enables information input operation such as designating and inputting or the like the destination location point or the like by the user. The input unit  201  may also be configured by a voice recognition device which recognizes a speech content of the user or the information intended to be input by analyzing a microphone or sound signals collected by the microphone. 
     The output unit  202  is configured by an image output device composed of liquid crystal panel or the like for displaying the client map or the like. When the input unit  201  is configured by a touch-screen type interface, touch type buttons are displayed on the image output device. Besides the image output device, the output unit  202  may also be configured by an audio output device which outputs audio signals related to image information displayed on the image output device. 
     The client storage unit  204  is configured to store a client map in which each location point is described by latitude and longitude. In the client map, a link connecting two location points apart from each other is described by a group of coordinate values or coordinate rows expressing a plurality of location points on the link. At least a part of the link may be described in relation to link identification information for identifying the link or a type of the road configured by the link. Moreover, a location range of a park, river, premises of facilities are described by coordinate rows expressing a plurality of location points on an outline of the range or a closed curve. Each range may be described in relation to a type of the object located in the range. 
     The client map may be the same map as the server map, or may be a map in which at least a part of the format differs from the server map. 
     The first client arithmetic processing element  210  is configured to generate designated location point information and then transmit the designated location point information to the navigation server  100 . “The designated location point information” is information as the basis of recognition of each coordinate value of designated location points which becomes the two end points of the server route. The first client arithmetic processing element  210  is configured to measure a current position of the navigation client  200  based on GPS signals or the like received by a GPS receiver (not illustrated) installed in the navigation client  200 . The first client arithmetic processing element  210  is configured to recognize a destination location point or the like input by the user through the input unit  201 . 
     The second client arithmetic processing element  220  is configured to receive route information from the navigation server  100  and to designate a location point in the client map based on the coordinate values of the designated location point included in the route information. The second client arithmetic processing element  220  is configured to make the output unit  202  output a client route superimposed on the client map, the client route being a route which has a constant arrangement relation with the location point and which matches a shape of the server route included in the route information. 
     The first client arithmetic processing element  210  and the second client arithmetic processing element  220  are each configured of a programmable computer. The program is downloaded to the navigation-client  200  through a network or installed through a storage medium. Each of the first client arithmetic processing element  210  and the second client arithmetic processing element  220  may be configured of a hardware, which is in part or in total physically independent and separate. 
     (Navigation Method) 
     An embodiment of a navigation method performed by the navigation system of the above configuration is explained. 
     At the navigation-client  200 , the first client arithmetic processing element  210  recognizes a destination location point (to be precise, the coordinate value thereof) p 2  of the user ( FIG. 2 /STEP  212 ). For example, a location point designated by the user through the input unit  201  is recognized as the destination location point p 2  in the client map displayed on the output unit  202 . 
     Marks indicating a plurality of destination location point candidates are displayed on the client map, and a destination location point candidate which corresponds to one mark selected among the marks by the user through the input unit  201  may be recognized as the destination location point p 2 . Among a plurality of POI (points of interest), a mark expressing a position of a POI classified in a preference segment which the user has registered in the navigation-client  200  through the input unit  201  in advance, may be displayed on the client map as a mark expressing the position of the destination location point candidate. 
     In addition, basic information such as a name, address, phone number, or e-mail address or the like of a facility or the like may be input or designated by the user through the input unit  201 , and a location point related to the basic information in the client map may be recognized as the destination location point p 2 . 
     A departure location point (to be precise, the coordinate value thereof) p 1  of the user is recognized by the first client arithmetic processing element  210  ( FIG. 2 /STEP  211 ). For example, a current location point of the navigation-client  200  at a time point the destination location point p 2  is recognized, is recognized as the departure location point p 1 . In addition, similar to the destination location point p 2 , a location point designated or the like by the user through the input unit  201  may be recognized as the departure location point p 1 . 
     Then, “designated location point information” including coordinate values of each of the departure location point P 1  and the destination location point p 2  of the navigation-client  200  is generated by the first client arithmetic processing element  210  ( FIG. 2 /STEP  214 ), and then the designated location point information is sent to the navigation server  100  ( FIG. 2 /refer to arrow 01). Client identification information for identifying the navigation-client  200  is transmitted to the navigation server  100  accompanied to the designated location point information. 
     Next, at the navigation server  100 , the first server arithmetic processing element  110  receives the designated location point information from the navigation-client  200  and recognizes each of the two designated location points based on the designated location point information ( FIG. 2 /STEP  112 ). For example, each of the departure location point p 1  and the destination location point p 2  included in the designated location point information is recognized as a first designated location point (to be precise, the coordinate value thereof) q 1  and a second designated location point (to be precise, the coordinate value thereof) q 2 , respectively. 
     A location point in the periphery of the departure location point p 1  may be recognized as the first designated location point q 1 . For example, a location point on the link in the shortest distance from the departure location point p 1  is recognized as the first designated location point q 1 . 
     Moreover, among the location points in the periphery of the departure location point (reference location point) p 1 , a location point in which a travelling cost of the user along a vicinity route configured by one or a plurality of links connecting the departure location point p 1  and such location point is relatively low, may be preferentially recognized as the first designated location point q 1  by the first server arithmetic processing element  110 . 
     For evaluating the travelling cost, a server map in which the travelling cost of the user in each link is described is used. A value of a function having at least one of a travelling distance, travelling time required, and physical load of the user, as a variable, corresponds to the travelling cost. In a case the user travels by a vehicle, a value of a function having at least one of a travelling distance of the vehicle, required travelling time, physical load of the user (driving load of the vehicle), predicted fuel consumption amount, and required toll, as a variable, corresponds to the travelling cost. 
     The travelling time required for each link can be recognized from road traffic information obtained from outside information source. In addition to a measuring equipment disposed for measuring the traffic volume of users or vehicles of each link and the navigation-client  200  as a probe device for measuring a current position in time series, a road traffic information center or the like configured to collect measurement results from the measuring equipment or the probe device and then analyzing the collected information to predict the required travelling time in each link, corresponds to the outside information source. The navigation server  100  may configure the road traffic information center. 
     As shown in  FIG. 3A , in a case where a location point which is close to the departure location point p 1  in straight-line distance but located on an opposite side of the departure location point p 1  with reference to a first factor Obs 1 (river, forest, park, building structure or its premises) where the user cannot pass through, is recognized as the first designated location point q 1 ( 1 ), the travelling cost is evaluated high as for the travelling distance of the user along the vicinity route (dashed line) becomes long. 
     On the other hand, as also shown in  FIG. 3A , in a case where a location point having a long straight-line distance from the departure location point p 1 , but located on the same side of the departure location point p 1  viewed from the first factor Obs1, is recognized as the first designated location point q 1 ( 2 ), the travelling cost is evaluated low as for the travelling distance of the user along the vicinity route (dashed line) becomes short. Therefore, among the two location points q 1 ( 1 ) and q 1 ( 2 ), the latter is recognized as the first designated location point q 1 . 
     Furthermore, as shown in  FIG. 3B , in a case the travelling distance of the user along the vicinity route (dashed line) is short, but the vicinity route passes through a second factor Obs2 (a road or an area with heavy traffic or slow traffic, a road with much slopes, a road which crosses a railroad crossing, or the like) which can be travelled by the user but difficult to travel, the travelling cost is evaluated high. The inclination manner of each link can be determined by using a server map in which each location point is described by a coordinate value including altitude in addition to latitude and longitude. 
     On the other hand, as also shown in  FIG. 3B , in a case where the travelling distance of the user along the vicinity route (dashed line) is long, but the vicinity route does not pass through the second factor Obs2, the travelling cost is evaluated low. Therefore, among the two location points q 1 ( 1 ) and q 1 ( 2 ), the latter is recognized as the first designated location point q 1 . 
     Moreover, as shown in  FIG. 4A , in a case where a location point which is close to the destination location point p 2  in straight-line distance, but is on the opposite side of the destination location point p 2  with reference to the first factor Obs1, is recognized as the second designated location point q 2 ( 1 ), the travelling cost is evaluated high as for the travelling distance of the user along the vicinity route (dashed line) becomes long. On the other hand, as also shown in  FIG. 4A , in a case where a location point having a long straight-line distance to the destination location point p 2 , but located on the same side of the destination location point p 2  viewed from the first factor Obs1, is recognized as the second designated location point q 2 ( 2 ), the travelling cost is evaluated low as for the travelling distance of the user along the vicinity route (dashed line) becomes short. Therefore, among the two location points q 2 ( 1 ) and q 2 ( 2 ), the latter is recognized as the second designated location point q 2 . 
     As shown in  FIG. 4B , in a case where the travelling distance of the user along the vicinity route (dashed line) is short, but the vicinity route passes through a second factor Obs2, the travelling cost is evaluated high. On the other hand, as also shown in  FIG. 4B , in a case where the travelling distance of the user along the vicinity route (dashed line) is long, but the vicinity route does not pass through the second factor Obs2, the travelling cost is evaluated low. Therefore, among the two location points q 2 ( 1 ) and q 2 ( 2 ), the latter is recognized as the second designated location point q 2 . 
     Next, one or a plurality of server routes configured by a plurality of links connecting the first designated location point q 1  and the second designated location point q 2  are searched by the first server arithmetic processing element  110  using the server map ( FIG. 2 /STEP  114 ). 
     For example, the server route is searched on a policy to make the travelling cost to the first designated location point q 1  and the second designated location point q 2  becomes minimum. The type of travelling cost designated by the user through the input unit  201  is sent to the navigation server  100  from the navigation-client  200  together with the designated location point information (refer to  FIG. 2 /arrow 01), and the server route may be searched so that the travelling cost of the designated type becomes minimum. 
     Specifically, as shown in  FIG. 5A , in a case where an exit and entry of a first designated area A 1 , in which the first designated location point q 1  is included, contacts a two-way traffic road (dashed line), a server route which makes the user move in a direction which is relatively easy to move out from the first designated area A 1  at the two-way traffic road is searched for. For example, in a case the two-way traffic road is a left-hand traffic road, a route R( 2 ) which moves out from the first designated area A 1  by turning left is preferentially searched as the server route instead of a route R( 1 ) which moves out from the first designated area A 1  by turning right. Contrary to this, in a case where the two-way traffic road is a right-hand traffic road, the other route R( 1 ) is preferentially searched as the server route. 
     As shown in  FIG. 5B , in a case where an exit and entry of a second designated area A 2 , in which the second designated location point q 2  is included, contacts a two-way traffic road (dashed line), a server route which makes the user move in a direction which is relatively easy to move into the second designated area A 2  at the two-way traffic road is searched for. For example, in a case the two-way traffic road is a left-hand traffic road, a route R( 2 ) which moves into the second designated area A 2  by turning left is preferentially searched as the server route instead of a route R( 1 ) which moves into the second designated area A 2  by turning right. Contrary to this, in a case where the two-way traffic road is a right-hand traffic road, the other route R( 1 ) is preferentially searched as the server route. 
     Next, “route information” in which the arrangement manner of the server route is expressed by coordinate values is generated by the second server arithmetic processing element  120  ( FIG. 2 /STEP  120 ), and then the route information is transmitted to the navigation-client  200  ( FIG. 2 /arrow 02) identified by client identification information annex to the designated location point information ( FIG. 2 /arrow 01). 
     The route information includes coordinate values of each of the plurality of location points on the server route including at least from the first designated location point q 1  to the second designated location point q 2 . The density of the plurality of location points can be appropriately adjusted by taking into account a communication cost or the like of the route information. Moreover, the density of location points may differ by being high or low, such that a location point density in an area of high importance such as an entrance from an ordinary road to an express highway or an exit from the express highway to the ordinary road is made higher than other places. 
     Furthermore, the arrangement manner of the server route may be expressed in the route information by at least one location point on the server route, and in addition, by one or a plurality of functions y=f(x) (x:latitude, y:longitude) defined with reference to the at least one location point and expressing a shape and a posture of the server route. By expressing at least a part of the arrangement manner of the server route including a plurality of location points by such function, the communication cost of the route information and the arithmetic processing load thereof are intended to be reduced. 
     The link information may include a level (high/low) of the travelling cost for each link and a designation of a display manner (color or brightness or the like) of each link according to the level of the travelling cost. 
     Then, at the navigation-client  200 , the route information is received by the second client arithmetic processing element  220 . Furthermore, a route having an arrangement manner in the client map which matches the arrangement manner expressed by the coordinate values included in the route information, is generated as the client route, and superimposed on the client map to be output by the output unit  202  ( FIG. 2 /STEP  220 ). 
     In a case the coordinate values of each of the plurality of location points on the server route are included in the route information, the plurality of the location points having such coordinate values are specified on the client map, and then drawing data of a line segment connecting the plurality of the location points are generated as the client route. The drawing data of the client route may be generated so that the output unit  202  displays each link based on a display manner according to at least one of the difference of the type of road and the travelling cost of each link, designated by the route information. 
     In addition, at least one location point on the server route and a location point having the coordinate values on the client map is specified in the route information, and then, drawing data which expresses the posture and shape by one or a plurality of functions y=f(x) with reference to the location point, is generated as the client route. 
     A plurality of types of client maps may be stored in the client storage unit  204  and the type of client map designated by the user through the input unit  201  may be displayed on the output unit  202 . 
     Other Embodiments of the Present Invention 
     According to the above embodiment, the server map corresponds to the “designated map” in which the travelling cost of the user of the navigation-client  200  in each link, is described and the navigation server  100  corresponds to the “designated device” using the designated map, and the first server arithmetic processing element  110  corresponds to the “first designated arithmetic processing element” using the designated map. 
     Alternatively, for at least a part of the navigation-clients  200 , the client map may correspond to the “designated map” and the navigation-client  200  may correspond to the “designated device” and the first client arithmetic processing element  210  may correspond to the “first designated arithmetic processing element”. 
     In such case, the departure location point p 1  or a location point in the periphery thereof is recognized as the first designated location point q 1  (refer to  FIG. 3A ,  FIG. 3B ), and the destination location point p 2  or a location point in the periphery thereof is recognized as the second designated location point q 2  (refer to  FIG. 4A ,  FIG. 4B ) by the first client arithmetic processing element  210 . 
     Then, the designated location point information in which each of the first designated location point q 1  and the second designated location point q 2  is expressed by coordinate values, is generated by the first client arithmetic processing element  210  (refer to  FIG. 2 /STEP  214 ). And then, the first server arithmetic processing element  110  directly recognizes the first designated location point q 1  and the second designated location point q 2  from the designated location point information.