Navigation system, route search server, route search method and route search program

A route search server connected to a navigation terminal transmitting route searching conditions via a network, the route search server comprising:

• a POI attribute information database accumulating POI attribute information, a network data edit means and a virtual node setup means,
• wherein the route search server determines whether there is a plurality of POIs in a departure location and/or a destination location by making reference to relevant data in the POI attribute information database,
• and where the route search server has determined a plurality of POIs, the virtual node setup means sets up a virtual node for connection to each node of the plurality of POI through links having a value similar to that of the link cost,
• while the network data edit means adds the virtual node to the searching network data, and a route search means searches for routes using the searching network data containing the added virtual node.

A route search method of searching a route from a departure node to a destination node using searching network data,

• wherein the navigation system includes a POI attribute information database accumulating POI attribute information, a network data edit means and a virtual node setup means,
• the route search method comprising the following steps:
• determining whether there is a plurality of POIs in a departure location and/or a destination location by making reference to relevant data in the POI attribute information database;
• and where the navigation system has determined a plurality of POIs, setting up a virtual node for connection to each node of the plurality of POIs through links having identical link cost by using the virtual node setup means;
• and
• adding the virtual node to the searching network data by using the network data edit means, and searching routes with the aid of route search means using the searching network data containing the added virtual node.

A route search method in a navigation system including a navigation terminal transmitting route searching conditions and a route search server connected to the navigation terminal via a network,

• wherein the route search server includes a POI attribute information database accumulating POI attribute information, a network data edit means, and a virtual node setup means,
• the method comprising the following steps:
• determining whether there is a plurality of POIs in a departure location and/or a destination location by making reference to relevant data in the POI attribute information database;
• and where the navigation system has determined a plurality of POIs, setting up a virtual node for connection to each node of the plurality of POIs through links having identical link cost by using the virtual node setup means;
• and
• adding the virtual node to the searching network data by using the network data edit means, and searching routes with the aid of a route search means using the searching network data containing the added virtual node.

A program which allows a computer constituting a route search server connected to a navigation terminal via a network transmitting route search conditions and including a POI attribute information database accumulating POI attribute information, a network data edit means, and a virtual node setup means, to execute the following processes:

• determining whether there is a plurality of POIs in a departure location and/or a destination location by making reference to relevant data in the POI attribute information database;
• and where the navigation system has determined a plurality of POIs, setting up a virtual node for connection to each node of the plurality of POIs through links having identical link cost by using the virtual node setup means;
• and
• adding the virtual node to the searching network data by using the network data edit means, and searching routes with the aid of a route search means using the searching network data containing the added virtual node.