JP2006350619A - Information distribution system and download method therefor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To heighten efficiency of a download after communication is cut off during the data download to an onboard terminal from an access point, in an information distribution system. <P>SOLUTION: Data are downloaded to the onboard terminal 20 from a service center 7 through the access point 10 on the basis of distribution requirement from a cellphone 3. When download resumption becomes possible after the download is suspended by the communication cutoff, necessity decision of the download resumption is performed. The necessity decision is performed on the basis of priority of information, requirement freshness of the information, a time to redownload completion or the like, and the resumption of the download is not performed about the data having no necessity because utility value of the downloaded data deteriorates even if the download is resumed. Thereby, a download time or a data communication charge can be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an information distribution system for downloading electronic information via a network and a download method in the information distribution system.

There are services that distribute various types of information to vehicles via the Internet and other networks.
For example, in the information distribution system described in Japanese Patent Application Laid-Open No. 2003-92639, a mobile terminal and a control server can communicate with each other via a network. Information distribution request to When the vehicle enters the communication cover range of the access point arranged at each point, the in-vehicle terminal and the access point automatically establish communication. The control server downloads the requested information as download data to the in-vehicle terminal via the access point.

This makes it possible to request information that is desired to be obtained anywhere during the movement.
And if the download is interrupted due to, for example, the traveling vehicle leaving the communication coverage area of the access point, the in-vehicle terminal automatically interrupts the download data when it enters the communication coverage area of the next access point. By designating a location and sending a download request from the middle to the new access point, it is possible to always download all the download data related to the requested information.
JP 2003-92639 A

However, in the above conventional download method, when the download is interrupted, the download is always resumed and all the download data requested first is downloaded. When it is not always necessary, there is a problem that it takes time to download and delays the download of other necessary data or increases the data communication fee.
Accordingly, an object of the present invention is to provide a highly efficient information distribution system that suppresses unnecessary restart of a download when the download is interrupted, and a method for downloading the same.

  Therefore, the present invention provides an information distribution system that downloads data from a service center to a mobile terminal via a predetermined network based on an information distribution request. Judgment is made on the necessity, download is not resumed when there is no need to resume download, and download is resumed when necessary.

  According to the present invention, even when the download is resumed, when the use value of the downloaded data becomes low and becomes invalid as information, that is, when there is no necessity, the download is not resumed. Charges can be reduced.

Hereinafter, an embodiment in which the present invention is applied to an information distribution system that transmits information to a vehicle as a moving body will be described.
FIG. 1 is a diagram showing an outline of a vehicle information distribution system.
The vehicle information distribution system 1 is configured such that data is downloaded from the service center 7 to the in-vehicle terminal 20 via the access point 10 based on a distribution request from the mobile phone 3.
The mobile phone 3 is connected to the base station 4, and the base station 4 is controlled and managed by the mobile phone control center 5 to form a mobile phone communication network Nm. Here, the mobile phone 3 has a web browsing function.
A control server 8 is installed in a service center 7 that provides an information distribution service, and is connected to a cache server 9 via the Internet Ni.
The service center 7 is also connected to the mobile phone control center 5 via the Internet or the like. Thereby, the mobile phone 3 can communicate with the service center 7 via the base station 4 and the mobile phone control center 5.

When a user wants to receive download of predetermined information, the user accesses the service center 7 from the mobile phone 3 and uses the web browsing function to make a distribution request for the information to be obtained, and also downloads the in-vehicle terminal (mobile) The ID number of the terminal 20 is transmitted to the control server 8.
When receiving the distribution request, the control server 8 of the service center recognizes the user using the telephone number of the mobile phone 3 issued from the mobile phone control center 5 as user identification information, and transmits a password to the mobile phone 3.
The password is input to the in-vehicle terminal 20 on the user side.

  The service center 7 collects the requested information and transmits data of information to be provided to the user to the cache server 9. The distribution information includes real-time information data in addition to data stored in advance at the service center 7 and searched data. In particular, in the case of real-time information such as an intersection image from an image distribution server (not shown) arranged at each point, not only the image data itself but also the address data of the image distribution server is included.

The cache server 9 stores data transmitted from the control server 8. An access point 10 is connected to the cache server 9, and the access points 10 are installed at appropriate intervals along the road, for example.
When the in-vehicle terminal 20 enters the communication cover range R of the access point 10, communication between the in-vehicle terminal 20 and the access point 10 is established. The in-vehicle terminal 20 transmits the ID number and password to the control server 8 via the access point 10.
The in-vehicle terminal 20 periodically transmits a reception confirmation signal to the access point 10 while communication with the access point 10 is established.

After authenticating with the ID number and password received from the in-vehicle terminal 20, the control server 8 transmits a file list to be downloaded to the cache server 9. The cache server 9 transmits the file list to the in-vehicle terminal 20 via the access point 10.
When the in-vehicle terminal 20 receives the file list, the in-vehicle terminal 20 transmits a download request indicating that transmission should start from the top data of the file list. When the cache server 9 receives this download request, the data in the file list is transmitted from the top to the in-vehicle terminal 20 via the access point 10 to start downloading.
The in-vehicle terminal 20 stores the transmitted download data in a storage device to be described later.
The above configuration is the same as that described in Japanese Patent Laid-Open No. 2003-92639. Therefore, the detailed description is referred to the description of the publication.

FIG. 2 shows the configuration of the in-vehicle terminal in the present embodiment.
The in-vehicle terminal 20 is connected to a vehicle-mounted navigation system 30 and an audio system 35.
The in-vehicle terminal 20 includes a communication unit 21 that can communicate with the access point 10, and a control circuit 22 that controls download is connected to the communication unit. An input unit 24, a storage device 26, and an ID setting unit 28 are connected to the control circuit 22.
In the ID setting unit 28, the ID number fixed to the in-vehicle terminal 20 is set.

The user operates the input unit 24 to input the password obtained from the control server 8 of the service center 7. In the in-vehicle terminal 20, the control circuit 22 stores the input password in the storage device 26. Note that the password can be input by in-vehicle communication instead of manual input by the user.
The input unit 24 further includes a necessity determination switch (not shown) used for selection of download resumption control. This will be described later.

The control circuit 22 sequentially stores the download data taken in via the communication unit 21 that has established communication with the access point 10 in the storage device 26. The communication unit 21 transmits a reception confirmation signal to the access point 10 at predetermined time intervals while communication with the access point 10 is established and downloading continues.
The navigation system 30 and the audio system 35 are connected to the control circuit 22 described above. The display 32 and the audio system 35 of the navigation system 30 function as a display unit for data downloaded to the in-vehicle terminal 20, and the control circuit 22 displays and outputs the data stored in the storage device 26 on the display 32 and the audio system 35.
Furthermore, the control circuit 22 can acquire data on the running state of the vehicle from the navigation system 30.

In this in-vehicle terminal 20, whether or not the download is resumed and continued when the next communication becomes possible when the download is interrupted due to, for example, the vehicle leaving the communication coverage range R of the access point 10 during the download. The necessity can be judged.
In the following, a description will be given mainly of the control relating to the necessity of restarting download with reference to the flowchart of FIG.
As described above, when the user makes a distribution request for information to the service center 7 using the mobile phone 3, receives the password and inputs the password to the in-vehicle terminal 20, the control circuit 22 stores the password in the storage device 26. save.

Then, following the input of the password, first, at step 101, the control circuit 22 prompts selection of necessity determination by the display on the navigation system 30 or the sound of the audio system 35.
When making the necessity determination, the user turns on the necessity determination switch of the input unit 24.
In step 102, the selection result of necessity determination is checked. If execution of necessity determination for resuming download is selected, the process proceeds to step 103. If not selected, the process proceeds to step 104.
In step 103, the control circuit 22 sets a necessity determination flag (ON), and proceeds to step 104. This necessity determination flag is a set with the previously input password. If there are a plurality of pieces of information requested for distribution and the passwords are different from each other, the necessity determination flags are distinguished from each other.

When the vehicle enters the communication coverage range R of the access point 10, communication is established and authentication is performed, and a file list relating to distribution request information is transmitted from the cache server 9.
In step 104, a download request indicating that transmission is to be performed from the top of the file list data (download data) is transmitted.
In step 105, data sequentially downloaded to the in-vehicle terminal 20 is accumulated in the storage device 26.

In step 106, it is checked whether the download is complete. This is done by the control circuit 22 confirming that all the data in the file list has been received.
When the download is completed, the process proceeds to step 124 where the control circuit 22 resets the necessity determination flag (OFF) and transmits a completion notification to the cache server 9 via the access point 10. As a result, the cache server 9 also notifies the control server 8 of completion and ends the download. The service center performs predetermined billing processing and the like.

During downloading, in step 107, the control circuit 22 monitors the output of the reception confirmation signal from the communication unit 21 and checks whether communication is in an established state. If communication is established (during communication), the process returns to step 105.
When the communication is interrupted, in step 108, the control circuit 22 causes the storage device 26 to store the interrupted portion of the download data.
At this time, the access point 10 detects that the reception confirmation signal from the in-vehicle terminal 20 has been interrupted and notifies the cache server 9, and the cache server 9 receives the notification and stops transmitting download data.

Next, in step 109, it is checked whether or not communication has been established by entering the communication coverage range R of the new access point 10 or the like. When this check is repeated and communication is established again, in step 110, the control circuit 22 transmits the ID number and password of the in-vehicle terminal 20.
In response to this, the control server 8 performs authentication, and notifies the cache server 9 connected to the currently communicating access point 10 of download resumption. The cache server 9 transmits a notification that download can be resumed to the in-vehicle terminal 20 via the access point 10.

When the control circuit 22 receives the notification that the download can be resumed in step 111, the control circuit checks in step 112 whether or not the necessity determination flag is set.
If the necessity determination flag is not set, the process proceeds to step 123, where the control circuit 22 reads the download data interruption point from the storage device 26, designates the interruption point, and transmits a download resumption request for downloading from the middle.
As a result, the cache server 9 calls the interruption point and transmits the data to the in-vehicle terminal 20 via the access point 10.
Thereafter, the process proceeds to step 105.

If the flag is set in the check in step 112, the process proceeds to step 113 and subsequent steps to determine whether to restart the download.
In the control circuit 22, a check is performed from the following viewpoint as the necessity of restarting download.
First, in step 113, the level of information priority in the information distribution service is checked. Here, the determination is made with reference to a table stored in the storage device 26 in advance.

For example, in the case of a series of information that is frequently updated at a predetermined cycle such as every 5 minutes, the number of downloads becomes excessive when data is downloaded after the interruption point, while the latest information ( Data) is obtained, it is determined that the priority is low. The update cycle used for determination is based on file information included in the file list.
When the priority is low, it is determined that there is no necessity, and the process proceeds to step 125, where the necessity determination flag is reset, and a restart cancellation request is transmitted to the effect that downloading from the interrupted location is not performed.

If it is determined in step 113 that the priority of the information is high, the process proceeds to step 114 as being necessary or effective as a download target.
In step 114, the required freshness of information is checked. This is because information is not updated periodically. For example, in a service where information that changes every moment, such as stock prices in the securities market, is provided in real time, the utility value is used for data after the time has passed. Based on not having.

Therefore, it is said that the required freshness is high for those requiring such latest information. Real-time information is based on file information included in the file list.
If the request freshness is high, the flow proceeds to step 125 as no necessity, resets the necessity determination flag, and transmits a restart suspension request not to download from the interrupted location.
As a result, the cache server 9 stops the download preparation, notifies the control server 8 to that effect, and ends the restart process.

If it is determined in step 114 that the requested freshness of information is low, the process proceeds to step 115 because it is necessary or effective as a download target.
In step 115, a time required for downloading the data amount after the interrupted portion by re-downloading, that is, a time until completion of re-downloading is predicted and calculated.

In the next step 116, it is checked whether the time until completion of re-downloading is shorter than the time until the next update timing of the information.
This is because if the time until the completion of re-downloading is equal to or greater than the update timing, it is not valid information because the data is already old when the data is acquired.
Therefore, if the time until the completion of the re-download is equal to or longer than the time until the next update timing of the information, the re-download is unnecessary, so the process proceeds to step 125, the necessity determination flag is reset, and the download from the interrupted point is performed. Sends a request to cancel the restart.

If it is determined in step 116 that the time until the completion of re-downloading is shorter than the time until the next update timing, the process proceeds to step 117 because it is necessary or effective as a download target.
In step 117, it is checked from the file information included in the file list whether the requested information is point information related to a specific point.
If the request information is point information, the process proceeds to step 118. If the request information is not point information, the process proceeds to step 121.

In step 118, the navigation system 30 is notified of the time until completion of the redownload obtained in the previous step 115, and the vehicle position (that is, information based on the downloaded data) at the time of completion of the redownload on the scheduled travel route is notified to the user. (Providable points that can be provided) are predicted.
In step 119, the predicted vehicle position at the completion of the re-download is acquired from the navigation system 30.

In the next step 120, the specific point of the request information is compared with the vehicle position at the completion of the re-download, and it is checked whether the vehicle position passes the specific point and is not too far from the predetermined distance.
This is because it is not useful if the vehicle position at the time when the information is provided is too far away from the specific point even though the distribution is requested because the information around the specific point on the planned travel route is requested.
Therefore, when the predicted vehicle position at the time of completion of re-downloading passes a specific point and is too far away from the predetermined distance, re-downloading is unnecessary, so the process proceeds to step 125 to reset the necessity determination flag and Sends a request to stop resuming that download is not performed.

On the other hand, when the predicted vehicle position at the time of completion of re-downloading is not too far from the specific point, the process proceeds to step 121 as being necessary or effective as a download target.
In step 121, the predicted arrival time until reaching the destination is acquired from the navigation system based on the traveling state. The destination includes a stopover point on the planned travel route.

In step 122, it is checked whether or not the time until completion of re-downloading obtained in the previous step 115 is shorter than the predicted arrival time.
This is because even if re-downloading is performed, if the user arrives at the destination or stopover point before getting all the data and the user gets out of the vehicle, it is useless and meaningless.
Therefore, if the time until completion of the re-download is equal to or longer than the predicted arrival time, re-download is unnecessary, so the process proceeds to step 125, the necessity determination flag is reset, and the restart is canceled that the download from the interrupted point is not performed. Send a request.

If the time until completion of re-downloading is shorter than the estimated arrival time in the check in step 122, the process proceeds to step 123 because it is necessary or effective as a download target.
As a result, a download restart request is transmitted from the control circuit 22 to the cache server 9 via the access point 10, and in response to this, data after the interrupt point is transmitted from the cache server 9 via the access point 10. It is transmitted to the in-vehicle terminal 20.
After this, the process returns to step 105.

According to the necessity determination process described above, when the password related to the information requested for distribution is first input to the in-vehicle terminal 20, the selection of whether or not the necessity determination is performed in steps 101 and 102 is performed. If communication is interrupted during download and an interruption is detected in step 107, the data interruption location is stored in step 108.
Thereafter, when communication is established and download can be resumed, it is checked in step 112 whether or not necessity judgment is selected. If not, download is resumed in step 123. When the download is completed through steps 105 and 106, a completion notice is given in step 124 and the process is terminated.

On the other hand, when the necessity determination is selected, the process proceeds from step 112 to step 113, and the necessity determination from each viewpoint is performed up to step 122. Note that if the information requested for distribution is not point information, the vehicle position at the time of completion of re-download is irrelevant, so steps 118 and 119 are omitted.
If it is determined from any one of the viewpoints that the value of the information after the download is low and unnecessary, the download is not resumed by issuing a restart stop request in step 125.

Also, if all the checks from each viewpoint are cleared and it is determined that there is a necessity, the information after the download is valuable and the download is considered to be finally effective, so the download is resumed in step 123 .
Here, all checks from each viewpoint from step 113 to step 122 are cleared, and when the download is valid, the download is automatically resumed. However, after step 122, the fact that the download is valid is displayed. In addition, after waiting for the user's confirmation operation, the process may proceed to the download restart in step 123.
Steps 112 to 122 in the above flow constitute determination means in the invention.

  The embodiment is configured as described above. In the information distribution system for downloading data from the service center 7 to the in-vehicle terminal 20 via the Internet Ni, the cache server 9 and the access point 10 based on the distribution request, When the download can be resumed, the necessity of resuming the download is determined, and even if the download is resumed, the use value of the downloaded data will be reduced, so the download will not be resumed for those that are not necessary As a result, download time and data communication charges can be reduced.

The necessity determination is performed from various viewpoints such as the priority of information, the freshness of information request, the time until completion of re-downloading, etc., so that the validity of the data to be downloaded can be accurately determined.
In particular, because the necessity judgment is made based on the comparison of the time until the completion of re-downloading and the time until the next update timing, the old data is acquired after the next update timing when new data is obtained. Can be avoided.

In addition, in the case of information about a specific point, the necessity determination is made based on a comparison between the vehicle position predicted from the time until the completion of re-downloading and the specific point. You can also avoid the situation that you have.
Note that the necessity determination described above is performed when the user selects at the time of password input, and therefore can be executed based on the user's intention.

  In the embodiment, the case has been described in which the communication is interrupted and the download is interrupted by leaving the communication cover range R of the access point 10 while the vehicle on which the in-vehicle terminal 20 is mounted travels. Download interruptions may occur due to the radio wave environment even within the communication range R of the same access point, or when another communication is performed in order to receive another service with a high priority by the user's own interruption operation. Arise. As described above, there are various causes of the download interruption, but the present embodiment can be applied as it is regardless of the cause.

  In the embodiment, the necessity of restarting download is determined for all of a plurality of viewpoints that are assumed according to the characteristics of the information. However, the necessity determination is performed only for necessary viewpoints according to the situation. May be. Furthermore, the user may be able to select a viewpoint for determining necessity or a combination thereof by operating the input unit 24 or the like.

In addition, the necessity of restarting download is determined by selecting the necessity judgment switch of the input unit 24 when the password is input to the in-vehicle terminal 20, but the initial setting of the necessity judgment switch is turned on. Therefore, the necessity determination can usually be always executed.
Alternatively, the necessity determination execution request is executed when the control circuit 22 receives a notification indicating that the download can be resumed from the cache server 9 instead of selecting the request when the initial password is input. It is also possible to display a selection screen as to whether or not to make a selection on a display or the like.
In addition, although the selection of the necessity for restarting the download is performed from the input unit 24 of the in-vehicle device 20, the selection is not limited to this, and for example, the selection is performed with a cursor or a touch switch on the display screen of the navigation system 30. May be.

Furthermore, although the embodiment shows an example in which an information distribution request is made from the mobile phone 3, the present invention is not limited to this, and the information distribution request may be made from the in-vehicle device 20.
Further, the necessity of restarting download is determined on the in-vehicle device 20 side, but may be determined on the control server 8 side of the service center 7. In particular, priority, requested freshness, time to download completion and comparison with update timing are also suitable for the control server 8 side, and sharing between the control server 8 side and the in-vehicle device 20 side from the viewpoint of necessity determination. You can also

It is a figure which shows the outline | summary of the information delivery system for vehicles. It is a figure which shows the structure of a vehicle-mounted terminal. It is a flowchart which shows the flow of control concerning the necessity determination of download resumption. It is a flowchart which shows the flow of control concerning the necessity determination of download resumption. It is a flowchart which shows the flow of control concerning the necessity determination of download resumption.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vehicle information distribution system 3 Mobile phone 4 Base station 5 Mobile phone control center 7 Service center 8 Control server 9 Cache server 10 Access point 20 In-vehicle terminal (mobile terminal)
DESCRIPTION OF SYMBOLS 21 Communication part 22 Control circuit 24 Input part 26 Storage device 28 ID setting part 30 Navigation system 32 Display 35 Audio system Ni Internet Nm Cell-phone communication network R Communication coverage

Claims (11)

In an information distribution system for downloading data from a service center to a mobile terminal via a predetermined network based on an information distribution request,
After the download is interrupted, it has a judgment means to judge the necessity of resuming the download when it becomes possible to resume the download.
An information distribution system configured to restart downloading when it is determined that there is no necessity for restarting download by the determining means, and when it is determined that there is necessity. The information distribution system according to claim 1, wherein the determination unit determines whether the download needs to be resumed when selected by a user. 3. The information distribution according to claim 1, wherein the determination unit determines the necessity of resuming download based on at least one of priority of information, freshness of requested information, and time until completion of re-downloading. system. 4. The information according to claim 1, wherein the determination unit determines the necessity of resuming the download based on a comparison between a time until completion of re-downloading and a time until the next update timing. Distribution system. The determination means determines necessity of resuming download based on a comparison between the specific point and a mobile terminal position predicted from a time until completion of re-downloading for information about the specific point periphery. 5. The information distribution system according to any one of 1 to 4. A download method in an information distribution system for downloading data from a service center to a mobile terminal via a predetermined network based on an information distribution request,
After the communication is interrupted and the download is interrupted, when it becomes possible to resume the download, a determination is made as to whether the download should be resumed.
A download method characterized in that download is not restarted when it is determined that there is no need to restart download, and download is restarted when it is determined that there is a need. The download method according to claim 6, wherein the necessity of restarting the download is determined when selected by a user. The download method according to claim 6 or 7, wherein the necessity of resuming the download is determined based on at least one of information priority, information request freshness, and re-download completion time. The download method according to any one of claims 6 to 8, wherein the necessity of resuming the download is determined based on a comparison between a time until completion of re-downloading and a time until the next update timing. 10. The necessity of restarting the download is determined on the basis of a comparison between the position of the mobile object predicted from the time until completion of re-downloading and the specific point with respect to information about the specific point. The download method according to any one of the above. The download is resumed after allowing the user to perform a confirmation operation when it is determined in the determination of the necessity of restarting the download that the download is necessary. Download method described.

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