| 摘要 |
<P>PROBLEM TO BE SOLVED: To prevent loss of a chance for a specific transmission destination to receive transmission of map information. <P>SOLUTION: A map database for recording map information for transmitting to a transmission destination in response to a transmission request therefrom to: specify, for each of plural transmission destinations, a data volume of yet-to-be-transmitted map information for each of a first range around a basic existence position of the transmission destination and a second range that includes the first range and is wider than the first range; cause yet-to-be-transmitted map information of the first range to be transmitted to a transmission destination prioritized in the ascending order of the data volume of the yet-to-be-transmitted map information of the first range among plural transmission destinations that have sent transmission requests, in the case of causing map information of the first range to be transmitted; and cause yet-to-be-transmitted map information of the second range to be transmitted to a transmission destination prioritized in the descending order of the data volume of the yet-to-be-transmitted map information of the second range among plural transmission destinations that have sent transmission requests, in the case of causing map information of the second range to be transmitted. <P>COPYRIGHT: (C)2013,JPO&INPIT |
