JP2010263337A - Download system based on access timing control, download method, download program, and recording medium with the program recorded therein - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce access contention to a content distribution section 100 when downloading the blocks of a content file not successively received owing to a broadcasting wave reception state, from the content distribution section 100 through radio communication. <P>SOLUTION: A terminal section 500 receives access timing control information by way of a television broadcasting station section 200 and the blocks, detects the blocks not successively received, generates block number information, and notifies an access timing management section 300 of the block number information via a radio communication station section 400. The access timing management section 300 calculates the latest access timing control information, based on the block number information. The terminal section 500 acquires the latest access timing control information from the access timing management section 300 via the radio communication station section 400, and acquires the blocks not successively received from the content distribution section 100 via the radio communication station section 400. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  In the present invention, a terminal having a broadcast wave reception function and a wireless communication function, such as a mobile phone and a car navigation system, divides content files such as video, audio, data, etc. into a predetermined size from the broadcast wave (broadcast). Download access timing control system for controlling the access timing to the server when the block of the content file that has been received by the received block and failed to be received due to the reception status of the broadcast wave is downloaded from the server via wireless communication (unicast), The present invention relates to a download access timing control method and a download access timing control program.

  Conventionally, with the spread of digital satellite broadcasting services, systems for broadcasting content files such as video, audio, and data to terminals have been provided. Further, a system for broadcasting a content file to a terminal using a frequency band of terrestrial analog television broadcasting has been studied (for example, see Non-Patent Document 1).

  When broadcasting a content file to a terminal using the broadcast wave as described above, the content file is divided into blocks of a prescribed size and broadcast. In such a case, there may be a case where the terminal fails to receive the block of the content file according to the broadcast wave reception status and cannot correctly receive all the blocks necessary for the configuration of the content file. Therefore, a communication / broadcasting-type content file distribution method in which communication and broadcasting are linked and a terminal downloads a block of a content file that could not be received by broadcasting from a server has been studied (for example, Non-Patent Document 2). reference).

  When downloading a block by communication, in order to avoid congestion due to a large amount of simultaneous access from the terminal to the server, generate a terminal-independent access timing on the server side, pass the access timing to each terminal in advance by broadcast waves, There is a method in which each terminal accesses the server based on the access timing to uniformly distribute the access timing from the terminal to the server (see, for example, Patent Document 1).

Tomoyuki Okamura, “Multimedia Broadcast“ ISDB-Tmm ””, Journal of the Institute of Image Information and Television Engineers, Vol.62, No.5 (2008 0501), pp.692-695 Satoshi Yamada, Yasushi Matsuoka, Tomoyuki Oya, “Characteristic evaluation of content distribution method linked to communication and broadcasting”, IEICE technical report, Vol. 108, no. 290, MoMuC 2008-62 (2008/11/13 · 14), pp. 5-9

Japanese Patent Application Laid-Open No. 11-219281, “Terminal-independent random number generation method and apparatus, recording medium on which terminal-independent random number generation program is recorded”

  However, the conventional method as described above is based on the premise that all terminals access the server, and each terminal receives a block based on the success or failure of receiving a broadcast wave. Access is not considered. Therefore, in the server and network design on the assumption that all terminals access the server, there is a problem that the resources of the server and the network cannot actually be used effectively.

  In addition, in response to the problem that the server and network resources cannot be used effectively in the access timing control based on the assumption that all terminals access the server as described above, each terminal has received a block successfully or unsuccessfully. It is possible to notify the server, the server calculates a new access timing for each terminal based on the counting result and notifies each terminal, and each terminal can access the server based on the access timing. In this case, the terminal that failed to notify the server of successful reception or unsuccessful access to the server at the initial access timing acquired from the broadcast wave allows the terminals to access the server. Causes a terminal that fails to acquire a block, or causes congestion. It can be considered.

  Therefore, the present invention has been made in view of the above-described conventional problems, and the object of the present invention is a terminal having a broadcast wave receiving function and a wireless communication function, such as a mobile phone and a car navigation system. Receives content files such as video, audio, and data from broadcast waves in blocks that are divided into predetermined sizes, and wirelessly communicates the blocks of content files that failed to be received due to the broadcast wave reception status (unicast) It is to control the access timing so that the server and network resources can be used effectively while reducing the server access timing between terminals when downloading from the server via the server.

In order to achieve the above object, a download system based on access timing control according to claim 1 includes a content distribution unit that distributes a block obtained by dividing a content file into a predetermined size, the content distribution unit, An access timing management means for exchanging information via the network, and information transmitted from the content distribution means via the second network, and receiving the first network and the first network A plurality of terminal devices for exchanging information with the content distribution means and the access timing management means via a communication network connected to
The access timing management means includes
Access timing control information indicating access timing for downloading a block that could not be received via the second network from the content distribution means via the communication network, wherein the terminal device Block number information notification time for notifying the access timing management means of the number of blocks that failed to receive the content file transmitted via the network, and the terminal device receives access timing control information from the access timing management means. A function of managing access control information including an access timing control information acquisition time for acquiring and a block acquisition time for acquiring the block that the terminal device has failed to receive from the content distribution means;
Based on the ID information of each terminal device, the block acquisition overall start time and the block number information notification time notified from the content distribution means, the block number information notification time uniformly distributed to each terminal device; Based on the ID information, access timing control information acquisition start time, and access timing control information acquisition time of each terminal device, the access timing control information acquisition times that are uniformly distributed to each terminal device are calculated. Distributed time calculation means;
The block acquisition time is divided by the number of the terminal devices based on the number of the terminal devices, the ID information of each terminal device, the block acquisition start time, and the block acquisition time permitting download from all the terminal devices to the content. Block acquisition time calculation means for calculating the block acquisition time from
Based on the existing access timing control information, the assumed total number of blocks set assuming the number of blocks notified from each terminal device, the block acquisition start time and the block acquisition time, the block acquisition is performed according to the estimated total number of blocks. An access timing control information updating means for updating the block acquisition time from the divided time and outputting the latest access timing control information;
The content distribution unit acquires the access timing control information from the access timing management unit, and transmits the access timing control information and a block obtained by dividing the content file into a predetermined size via a second network. A function and a function of transmitting the requested acquisition block via the first network and the communication network based on the latest or existing access timing control information managed by the access timing management means. ,
The terminal device
Broadcast processing means for receiving access timing control information and a block of a content file transmitted from the content distribution means via a second network and storing them in a storage means;
Communication processing means for exchanging information with the communication network;
Block information management means for detecting a block that has failed to be received based on the block stored in the storage means, and managing the ID and content file name of the detected block as block information;
By referring to the block number information notification time in the access timing control information stored in the storage means, the total number of block IDs of the block information managed by the block information management means and the content when the corresponding time comes Processing of notifying the access timing management means via the communication processing means as the file name and terminal device ID as block number information;
With reference to the access timing control information acquisition time in the access timing control information stored in the storage means, the access timing control means transmits the access timing control information via the communication processing means when the corresponding time is reached. Processing to acquire the latest access timing control information from the management means, and update the access timing control information stored in the storage means with the acquired information;
Main processing for referring to the block acquisition time in the access timing control information stored in the storage means and issuing a signal for notifying the block information acquired from the block information management means when the corresponding time is reached. Control means;
Upon receipt of the block information issued from the main control means, the content distribution means is accessed via the communication processing means, and the block with the block ID corresponding to the file name described in the block information is obtained. And block acquisition processing means for performing processing for storing in the storage means.

According to a fifth aspect of the present invention, there is provided a download method based on access timing control, wherein a content distribution unit that distributes a block obtained by dividing a content file into a predetermined size, and information is transmitted via the content distribution unit and the first network An access timing management means for performing transmission and reception; information transmitted from the content distribution means via a second network; and a communication network connected to the first network and the first network A plurality of terminal devices that exchange information with the content distribution means and the access timing management means,
The access timing management means is access timing control information indicating an access timing for downloading a block that could not be received via the second network from the content distribution means via the communication network, Block number information notification time for notifying the access timing management means of the number of blocks in which the terminal device has failed to receive the content file transmitted via the second network, and the terminal device managing access timing Access control information including an access timing control information acquisition time for acquiring access timing control information from the means and a block acquisition time for acquiring from the content distribution means the block that the terminal device has failed to receive. Sys has the function to manage A download method based on the access timing control in the arm,
Based on the ID information of each terminal device, the block acquisition total start time, and the block number information notification time notified from the content distribution unit, the distributed time calculation unit of the access timing management unit is assigned to each terminal device. The block number information notification time and the terminal device ID information, the access timing control information acquisition start time, and the access timing control information acquisition time are uniformly distributed to the terminal devices. A distributed time calculating step of calculating the access timing control information acquisition time;
The block acquisition time calculation means of the access timing management means is based on the number of the terminal devices, the ID information of each terminal device, the block acquisition start time, and the block acquisition time that allows downloading from all the terminal devices for the content, A block acquisition time calculating step for calculating the block acquisition time from a time obtained by dividing the block acquisition time by the number of the terminal devices;
The access timing control information updating unit of the access timing management unit sets the existing access timing control information, the assumed total number of blocks set assuming the number of blocks notified from each terminal device, the block acquisition start time, and the block acquisition time. An access timing control information update step for updating the block acquisition time from the time obtained by dividing the block acquisition time by the assumed total number of blocks and outputting the latest access timing control information;
A content distribution unit obtains the access timing control information from the access timing management unit, and transmits the access timing control information and a block obtained by dividing the content file into a predetermined size via a second network. When,
A broadcast processing step in which the broadcast processing means of the terminal device receives the access timing control information and the block of the content file transmitted from the content distribution means via the second network and stores them in the storage means;
Block information management in which block information management means of the terminal device detects the block that has failed to be received based on the block stored in the storage means, and manages the ID and content file name of the detected block as block information Steps,
Blocks managed by the block information management unit when the main control unit of the terminal device refers to the block number information notification time in the access timing control information stored in the storage unit and the corresponding time is reached. Notifying the access timing management means through the communication processing means as the block number information of the total number of block IDs of information, content file names and terminal device IDs;
The main control means of the terminal device refers to the access timing control information acquisition time in the access timing control information stored in the storage means, and when the corresponding time is reached, the access timing control information is transmitted to the communication processing means. The access timing management means, and obtaining the latest access timing control information from the management means, and updating the access timing control information stored in the storage means with the acquired information;
The main control means of the terminal device refers to the block acquisition time in the access timing control information stored in the storage means, and notifies the block information acquired from the block information management means when the time comes. Emitting a signal;
The block acquisition processing unit of the terminal device receives the notification of the block information issued from the main control unit, accesses the content distribution unit via the communication processing unit, and sets the file name described in the block information. A block acquisition processing step for performing processing for acquiring a block having a corresponding block ID and storing the block in the storage unit;
A step in which the content distribution means transmits the requested block through the first network and the communication network based on the latest or existing access timing control information managed by the access timing management means; It is characterized by having.

In particular,
(1) In a system in which a terminal receives a content file from a broadcast station as a block divided into a prescribed size via broadcast and accesses the server to download a block that has failed to be received from the server.
Broadcasting a content file block from a broadcasting station to each terminal, and simultaneously broadcasting access timing for each terminal to be distributed to the server and accessing each terminal;
Means for detecting a block that the terminal has failed to receive and notifying the server of the number of blocks required for download;
Means for counting the number of blocks notified from each terminal by the server, and determining the latest access timing at which each terminal accesses the server based on the total value;
Means for each terminal to obtain the latest access timing determined by the server from the server;
Each terminal downloads a block of a content file by accessing the server based on the access timing acquired from the broadcasting station or the latest access timing acquired from the server.
(2) At the access timing from the broadcasting station of (1), the time allowed for downloading the content from the total number of terminals is divided by the total number of terminals, and the time for downloading is allocated to each terminal, Access to servers from terminals is uniformly distributed.
(3) In the determination of the latest access timing of (1), the server calculates the total number of blocks notified to the server by each terminal, and downloads the content from the total number of terminals with the total value. The time to allow is divided | segmented and the time for determining the newest access timing with respect to each terminal is calculated.
(4) In the download based on the access timing of (1) above, if each terminal can obtain the latest access timing from the server, the download can be carried out and obtained based on the latest access timing. If not, downloading is performed based on the access timing acquired from the broadcasting station.
(5) In the calculation of the latest access timing in (1), the access timing assigned to the terminal is compared with the time calculated in (3) by means of (2) and assigned to the terminal. By assigning the time calculated in the above (3) to a certain access timing, access to the server of the terminal that failed to obtain the latest access timing calculated by the server and the terminal that succeeded in obtaining the latest access timing It is characterized by reducing the collision.

  According to the first to tenth aspects of the present invention, a terminal having a broadcast wave receiving function and a wireless communication function, such as a mobile phone or a car navigation system, can receive video, audio, data, etc. from a broadcast wave (broadcast). Access to the server when the content file is received in blocks divided into a predetermined size and the block of the content file that failed to be received due to the broadcast wave reception status is downloaded from the server via wireless communication (unicast) The access timing can be controlled so that the server and network resources can be used effectively while reducing the batting of access to the server between the terminals.

1 is a configuration diagram illustrating an entire download access timing control system according to an embodiment of the present invention. FIG. It is a flowchart which shows the whole process of the download access timing control system by embodiment of this invention. 3 is a functional block diagram of a content distribution unit 100 and an access timing management unit 300 according to an embodiment of the present invention. FIG. It is a functional block diagram of the terminal part 500 by embodiment of this invention. It is explanatory drawing which shows the definition of various time and time by embodiment of this invention. It is explanatory drawing which shows the access timing control information by embodiment of this invention. It is explanatory drawing which shows the access control object information by embodiment of this invention. The outline | summary of calculation of the block acquisition time by embodiment of this invention is represented, (a) is a flowchart, (b) is a time chart. An outline of calculation of the latest block acquisition time according to the embodiment of the present invention is shown, (a) is a flowchart, and (b) is a time chart.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings, but the present invention is not limited to the following embodiments.

  FIG. 1 shows an overall configuration of a download access timing control system according to an embodiment of the present invention. The download access timing control system of FIG. 1 includes a content distribution unit (server) 100 as a content distribution unit, a television broadcasting station unit (second network) 200, an access timing management unit 300 as an access timing management unit, and a wireless communication station unit. (Communication network) 400 and a terminal unit 500 as a plurality of terminal devices.

  The content distribution unit 100, the access timing management unit 300, and the wireless communication station unit 400 are connected by an IP network (first network).

  The content distribution unit 100 broadcasts content files such as video, audio, and data to the terminal unit 500 through the television broadcasting station unit 200 in blocks obtained by dividing the content files into predetermined sizes.

  The content is divided using a technology such as FLUTE (RFC 3926: File Delivery over Unidirectional Transport), and each block has a file name of the content file, the number of blocks constituting the content file (the number of blocks), and the ID of the own block. It shall have.

  In addition, the content distribution unit 100 includes access timing control information indicating access timing for downloading a block that the terminal unit 500 could not receive by broadcasting from the content distribution unit 100 via the wireless communication station unit 400. It is acquired from 300 and broadcasted to the terminal unit 500 via the TV broadcasting station unit 200.

  Here, the exchange between the content distribution unit 100 and the terminal unit 500 may use multicast transmission or unicast transmission in wireless communication or wired communication as well as broadcasting via the television broadcasting station unit 200.

  Furthermore, the content distribution unit 100 distributes the requested block to the terminal unit 500 in response to a block acquisition request that is a request for a block coming from the terminal unit 500 via the wireless communication station unit 400 and the IP network.

  The access timing management unit 300 notifies the content distribution unit 100 of access timing control information in response to a request from the content distribution unit 100.

  In addition, the access timing management unit 300 receives block number information indicating the number of blocks necessary for the terminal unit 500 to download from the terminal unit 500 via the wireless communication station unit 400.

  Further, the access timing management unit 300 generates the latest access timing control information based on the aggregation result of the block number information from the terminal unit 500 and the existing access timing control information notified from the terminal unit 500, and performs wireless communication. The terminal unit 500 is notified via the local unit 400.

  Here, the exchange between the access timing management unit 300 and the terminal unit 500 may use not only wireless communication but also wired communication.

  The terminal unit 500 receives access timing control information broadcast from the content distribution unit 100 via the television broadcast station unit 200.

  In addition, the terminal unit 500 receives a block broadcast from the content distribution unit 100 via the television broadcast station unit 200. At this time, a block that has been successfully received by the terminal unit 500 and a block that has failed to be received are generated according to the broadcast wave reception status in the terminal unit 500.

  The terminal unit 500 detects a block that has failed to be received using a technique such as FLUTE, and records the file name, block ID, and total number of blocks that have failed to be received.

  Also, the terminal unit 500 notifies the access timing management unit 300 of the block number information via the wireless communication station unit 400 based on the access timing control information acquired via the television broadcast station unit 200.

  In addition, the terminal unit 500 accesses the access timing management unit 300 via the wireless communication station unit 400 based on the access timing control information acquired via the television broadcast station unit 200, and acquires the latest access timing control information.

  Here, if the latest access timing control information can be acquired, the access timing control information is used to determine the acquisition timing of the block that has failed to be received, and the latest access timing control information due to deterioration of the communication status, etc. When the control information cannot be acquired, the access timing control information that has already been acquired via the television broadcasting station 200 is used to determine the acquisition timing of the block that has failed to be received.

  Further, the terminal unit 500 accesses the content distribution unit 100 via the wireless communication station unit 400 based on the access timing control information, and acquires the block that failed to be received via the television broadcast station unit 200 (block acquisition). To implement via.

  FIG. 2 shows an overall flow of the download access timing control system according to the embodiment of the present invention. In FIG. 2, only main processing is shown.

  First, access timing control information for a content file broadcast by the content distribution unit 100 is acquired from the access timing management unit 300 (step S11).

  Next, the content distribution unit 100 broadcasts the block obtained by dividing the content file into a predetermined size and the access timing control information acquired from the access timing management unit 300 to the terminal unit 500 via the television broadcasting station unit 200 (step S12).

  Then, the terminal unit 500 receives the access timing control information and the block broadcast from the television broadcast station unit 200 (step S13).

  Further, the block that the terminal unit 500 has failed to receive is detected using a technique such as FLUTE, and is generated and recorded as block number information (step S14).

  Next, the terminal unit 500 notifies the access timing management unit 300 of the block number information via the wireless communication station unit 400 based on the access timing control information acquired via the television broadcast station unit 200 (step S15).

  Then, the access timing management unit 300 calculates and generates the latest access timing control information based on the block number information notified from the terminal unit 500 via the wireless communication station unit 400 (step S16).

  Next, the terminal unit 500 acquires the latest access timing control information from the access timing management unit 300 via the wireless communication station unit 400 based on the access timing control information acquired via the television broadcast station unit 200 (step S17).

  Finally, based on the latest access timing control information acquired by the terminal unit 500 or the existing access timing control information acquired via the television broadcasting station unit 200, a block is acquired from the content distribution unit 100 via the wireless communication station unit 400 (step S18). ).

  Here, when the latest access timing control information can be acquired via the wireless communication station 400, the terminal unit 500 uses the latest access timing control information and acquires via the wireless communication station 400 due to a communication failure. If not, the existing access timing control information acquired via the television broadcasting station 200 is used.

  3 shows a functional configuration of the content distribution unit 100 and the access timing management unit 300 in FIG. 1, and FIG. 4 shows a functional configuration of the terminal unit 500 in FIG.

  The content distribution unit 100 records terminal unit ID information in which the content file, the file name of the content file, the number of terminal units 500 (number of terminals) that are the reception targets of the content file, and the ID (terminal unit ID) of each terminal unit 500 are recorded. The number of assumed blocks, the entire block acquisition start time, and the entire block acquisition end time are managed.

  Here, it is assumed that the number of terminals and the terminal unit ID, which are content file reception targets, are managed when the service provided by the present system is subscribed, and are acquired by another means such as a contract.

  Further, the assumed number of blocks is an assumption of the number of blocks requested from each terminal unit 500. When the operator of the content distribution unit 100 registers a content file, the number of blocks of the content file is determined from each terminal unit 500. Set the expected number of blocks required. For example, 1% of the number of blocks of the content file is set as the number of blocks requested from each terminal unit 500.

  FIG. 5 shows definitions of various times and times according to the embodiment of the present invention.

  In FIG. 5, the entire block acquisition start time is the time when the entire terminal unit 500 starts access to the access timing management unit 300 and the content distribution unit 100 via the wireless communication station unit 400.

  The entire block acquisition end time is a time at which the entire terminal unit 500 ends access to the access timing management unit 300 and the content distribution unit 100 via the wireless communication station unit 400.

  The block acquisition total time is the time required for the entire block acquisition from the terminal unit 500 via the wireless communication station unit 400, and is calculated from block acquisition total time = block acquisition total end time−block acquisition total start time.

  The block number information notification time is a value set when the operator of the content distribution unit 100 registers a content file, and the terminal unit 500 notifies the access timing management unit 300 of the block number information via the wireless communication station unit 400. Used as time to do.

  The access timing control information acquisition time is a value set when the operator of the content distribution unit 100 registers a content file, and the terminal unit 500 sends the latest access timing control information via the wireless communication station unit 400 to the access timing management unit 300. Used as the time to get from.

  The block acquisition time is a time for the terminal unit 500 to perform block acquisition from the content distribution unit 100 via the wireless communication station unit 400, and block acquisition time = block acquisition total time−block number information notification time−access timing control information Calculated from the acquisition time.

  The access timing control information acquisition start time is a time when the entire terminal unit 500 starts acquiring access timing control information from the access timing management unit 300 via the wireless communication station unit 400. Access timing control information acquisition start time = total block acquisition start time + block number information notification time.

  The block acquisition start time is the time when the entire terminal unit 500 starts to acquire a block from the content distribution unit 100 via the wireless communication station unit 400. Block acquisition start time = total block acquisition start time + block number information notification time + access timing information acquisition time.

  The block number information notification time is a time when the terminal unit 500 notifies the access timing management unit 300 of the block number information, and a different time is calculated for each terminal unit 500. The block number information notification time is a time between the block acquisition overall start time and the access timing control information acquisition start time, and is calculated so as to be uniformly distributed between these times as described later.

  The access timing control information acquisition time is a time at which the terminal unit 500 accesses the access timing management unit 300 in order to acquire the latest access timing control information from the access timing management unit 300. Calculated. The access timing control information acquisition time is a time between the access timing control information acquisition start time and the block acquisition start time, and is calculated so as to be uniformly distributed between these times as described later.

  The block acquisition time is a time at which the terminal unit 500 acquires a block from the content distribution unit 100 via the wireless communication station unit 400, and a different time is calculated for each terminal unit 500. The block acquisition time is a time between the block acquisition start time and the entire block acquisition end time, and is calculated so as to be uniformly distributed between these times as described later.

  In FIG. 3, the content distribution unit 100 notifies the access timing management unit 300 of a file name, the number of terminals, terminal unit ID information, the number of assumed blocks, a block acquisition total start time, and a block acquisition total end time.

  Then, access timing control information is acquired from the access timing management unit 300.

  FIG. 6 shows an example of access timing control information according to the embodiment of the present invention. In FIG. 6, the access timing control information is composed of a file name and an access timing information table. The access timing information table includes a terminal unit ID, a block number information notification time, an access control information acquisition time, and a block acquisition time.

  The content distribution unit 100 broadcasts the access timing control information acquired from the access timing management unit 300 and blocks corresponding to the number of divisions of the content file to the terminal unit 500 via the television broadcasting station unit 200.

  In addition, the content distribution unit 100 has a function of transmitting the block to the terminal unit 500 via the wireless communication station unit 400 in response to a block acquisition request from the terminal unit 500 via the wireless communication station unit 400.

  The access timing management unit 300 includes a setting information management unit 310, an access control target management unit 320, a basic parameter calculation unit 330, a distributed time calculation unit 340 as a distributed time calculation unit, and a block acquisition time calculation unit as a block acquisition time calculation unit. 350, an access timing control information updating unit 360 as an access timing control information updating unit, a communication processing unit 370, and a main control unit 380. Each function to be described later of each of the units 310 to 380 is achieved by, for example, a computer.

  The setting information management unit 310 holds the block number information notification time and the access timing control information acquisition time as setting values.

  The access control target management unit 320 manages the file name, the assumed number of blocks, the assumed total number of blocks, the block acquisition start time, and the block acquisition time notified via the main control unit 380 as access control target information.

  FIG. 7 shows access control target information according to the embodiment of the present invention. Here, the assumed total number of blocks is calculated by the main control unit 380 by the number of terminals × the assumed number of blocks.

  Based on the block acquisition total start time, block acquisition total end time, block number information notification time, and access timing control information acquisition time notified from the main control unit 380, the basic parameter calculation unit 330 determines the block acquisition total time, access timing The control information acquisition start time, block acquisition start time, and block acquisition time are calculated, and the calculation results are returned to the main control unit 380.

  The distributed time calculation unit 340 calculates the block number information notification time for each terminal unit 500 from the terminal unit ID information notified from the main control unit 380, the block acquisition overall start time, and the block number information notification time, and the terminal The terminal unit ID corresponding to the terminal unit ID included in the unit ID information and the block number information notification time corresponding to the terminal unit ID are returned to the main control unit 380.

  Also, the distributed time calculation unit 340 acquires access timing control information for each terminal unit 500 from the terminal unit ID information, access timing control information acquisition start time, and access timing control information acquisition time notified from the main control unit 380. The time is calculated and the terminal unit ID and the access timing control information acquisition time corresponding to the terminal unit ID are returned to the main control unit 380.

  Here, the block number information notification time is calculated so as to be uniformly distributed to each terminal unit 500. For example, block number information notification time = block acquisition overall start time + block number information notification time × “uniform random number between 0 and 1”.

  Also, the access timing control information acquisition times are calculated so as to be uniformly distributed among the terminal units 500. For example, access timing control information acquisition time = access timing control information acquisition start time + access timing control information acquisition time × “uniform random number between 0 and 1”.

  The block acquisition time calculation unit 350 calculates the block acquisition time for each terminal unit 500 from the number of terminals, the terminal unit ID information, the block acquisition start time, and the block acquisition time notified from the main control unit 380. The terminal unit ID corresponding to the terminal unit ID included in the ID information and the block acquisition time corresponding to the terminal unit ID are returned to the main control unit 380.

  FIG. 8 shows an outline of calculation of the block acquisition time according to the embodiment of the present invention.

  In FIG. 8, the block acquisition time calculation unit 350 divides the block acquisition time by the number of terminals, and sets the result as slot time_witdh (step S21). Then, the block acquisition time is calculated from the block acquisition time = block acquisition start time + time_width × i (the initial value of i is 0 and incremented by the number of repetitions), and the terminal unit ID with a smaller number (FIG. 8B) Then, the calculation result (block acquisition time) is assigned from 00001) and repeated for the number of terminals (steps S22 to S27).

  Then, the block acquisition time calculation unit 350 responds to the main control unit 380 with the terminal unit ID corresponding to the terminal unit ID included in the terminal unit ID information and the block acquisition time corresponding to the terminal unit ID.

  The access timing control information update unit 360 is notified from the main control unit 380 of the existing access timing control information that the terminal unit 500 already has, the assumed total number of blocks, the block acquisition start time, and the block acquisition time. The latest block acquisition time for the ID is calculated, the block acquisition time in the access timing control information is updated, and the response is sent to the main control unit 380 as the latest access timing control information.

  FIG. 9 shows an outline of calculation of the latest block acquisition time according to the embodiment of the present invention. In FIG. 9, the access timing control information updating unit 360 divides the block acquisition time by the assumed total number of blocks, and calculates the slot time_width (unit time width) (step S31).

  Next, the block acquisition time in the existing access timing control information is acquired as time_old (initial time) (step S32).

  Further, the initial value of i is set to 0 (step S33), time_tmp (provisional time) is calculated from the block acquisition start time + time_width × i (step S34), and time_old and time_tmp are compared (step S35). As a result, when time_old is larger than time_tmp, time_tmp is set to time_new (step S36).

  This process (provisional time calculation / comparison process) is repeated until time_old ≦ time_tmp (in the meantime, i is incremented by the number of repetitions (step S37)). Finally, time_new is set as the latest block acquisition time, and the access timing The block acquisition time of the control information is updated (step S38).

  The communication processing unit 370 is used for the access timing management unit 300 to communicate with the terminal unit 500 via the wireless communication station unit 400. When the communication processing unit 370 receives a block number information notification from the terminal unit 500, the main control unit 380 To notify the block number information.

  Here, the block number information includes a file name, a terminal unit ID, and a block number.

  In addition, when the communication processing unit 370 receives a request for the latest access timing control information from the terminal unit 500, the communication processing unit 370 receives the access timing control information that the terminal unit 500 already has from the terminal unit 500, and the main control unit 380 is notified.

  Furthermore, when receiving the latest access timing control information from the main processing unit 380 to the terminal unit 500, the communication processing unit 370 transmits the notification to the terminal unit 500 via the wireless communication station unit 400.

  The main control unit 380 is notified of the content name, the number of terminals, the terminal ID information, the assumed number of blocks, the block acquisition start time, and the block acquisition end time from the content distribution unit 100.

  Further, the main control unit 380 acquires the block number notification time and the access timing control information acquisition time from the setting information management unit 310, and sends the block acquisition total start time, block acquisition total end time, block count to the basic parameter calculation unit 330. The number information notification time and the access timing control information acquisition time are notified, and the block acquisition total time, access timing control information acquisition start time, block acquisition start time, and block acquisition time are obtained as responses.

  Further, the main control unit 380 notifies the distributed time calculation unit 340 of the terminal unit ID information, the block acquisition total start time, the block number information notification time, the terminal unit ID information, the access timing control information acquisition start time, and the access timing control information. The acquisition time is notified, and for each notification, the terminal unit ID for the terminal unit ID included in the terminal unit ID information, the block number information notification time corresponding to the terminal unit ID, and the terminal unit ID information The terminal part ID for the included terminal part ID and the access timing control information acquisition time corresponding to the terminal part ID are obtained as a response.

  Further, the main control unit 380 notifies the block acquisition time calculation unit 350 of the number of terminals, terminal unit ID information, block acquisition start time, and block acquisition time, and the terminal unit included in the terminal unit ID information as a response to the notification. The terminal part ID corresponding to the ID and the block acquisition time corresponding to the terminal part ID are obtained.

  Further, the main control unit 380 notifies the access control target management unit 320 of the file name, the assumed number of blocks, the assumed total number of blocks calculated by multiplying the assumed number of blocks and the number of terminals, the block acquisition start time, and the block acquisition time. .

  Further, the main control unit 380 responds to the notification of the file name, the number of terminals, the terminal ID, the number of assumed blocks, the block acquisition total start time, and the block acquisition total end time from the content distribution unit 100 with respect to the file name, the terminal unit ID. The access timing control information (for example, the information in FIG. 6) including the block number information notification time, the access timing control information acquisition time, and the block acquisition time is returned.

  Further, the main control unit 380 is notified of block number information (file name, terminal unit ID, number of blocks) from the communication processing unit 370. Then, the number of assumed blocks for the file name is acquired from the access control target management unit 320, and the difference in the number of blocks with respect to the number of assumed blocks (the number of assumed blocks−the number of blocks) is added to the assumed total number of blocks of the access control target management unit 320. .

  The main control unit 380 also acquires existing access timing control information acquired from the terminal unit 500 via the communication processing unit when the terminal unit 500 makes a request for acquiring the latest access timing control information to the access timing management unit 300. And the access timing control information update unit 360 to notify the access timing control information update unit 360 of the assumed total number of blocks corresponding to the file name that can be acquired from the access control target management unit 320, the block acquisition start time, and the block acquisition time. Timing control information is acquired as a response.

  Further, the main control unit 380 transmits the acquired latest access timing control information to the terminal unit 500 via the communication processing unit 370.

  As shown in FIG. 4, the terminal unit 500 includes a broadcast processing unit 510 as a broadcast processing unit, a storage unit 520 as a storage unit, a main control unit 530 as a main control unit, and a block information management unit 540 as a block information management unit. The block acquisition processing unit 550 as a block acquisition processing unit and the communication processing unit 560 as a communication processing unit.

  The broadcast processing unit 510 receives access timing information and a block broadcast from the content distribution unit 100 via the television broadcast station unit 200 and stores them in the storage unit 520.

  The broadcast processing unit 510 notifies the main control unit 530 of the completion of reception after reception of the block is completed. At this time, blocks that have been successfully received and blocks that have failed are generated according to the reception status of the terminal unit 500 in the broadcast wave, and only successful blocks are stored in the storage unit 520.

  The storage unit 520 stores access timing information and blocks from the broadcast processing unit 510.

  Based on the file name notification from the main control unit 530, the block information management unit 540 detects a block that has failed to be received from the block corresponding to the file name in the storage unit 520, and blocks the file name and its block ID. Manage as information.

  Based on the reception completion notification from the broadcast processing unit 510, the main control unit 530 notifies the block information management unit 540 and acquires the block information.

  Also, the main control unit 530 refers to the block number information notification time in the access timing control information stored in the storage unit 520, and when the corresponding time is reached, the total number of block IDs (number of blocks) of the block information. And the file name and the terminal unit ID are notified to the access timing management unit 300 via the communication processing unit 560 as block number information.

  In addition, the main control unit 530 refers to the access timing control information acquisition time in the access timing control information stored in the storage unit 520, and when the corresponding time is reached, the main control unit 530 transmits the existing access timing control information to the communication processing unit. The access timing management unit 300 is notified via the URL, the latest access timing control information is acquired, and the access timing control information in the storage unit 520 is updated.

  Further, the main control unit 530 refers to the block acquisition time in the access timing control information stored in the storage unit 520, and blocks the block information acquired from the block information management unit 540 when the corresponding time is reached. The acquisition processing unit 550 is notified.

  The block acquisition processing unit 550 accesses the content distribution unit 100 via the communication processing unit 560, acquires a block with a block ID corresponding to the file name described in the block information from the content distribution unit 100, and stores it in the storage unit 520. save.

  When receiving the notification of the block number information from the main control unit 530, the communication processing unit 560 notifies the access timing management unit 300 of the block number information via the wireless communication station unit 400.

  In addition, when receiving the notification of the existing access timing control information from the main control unit 530, the communication processing unit 560 notifies the access timing management unit 300 of the existing access timing control information via the wireless communication station unit 400, and accesses The latest access timing control information is acquired from the timing management unit 300 and responds to the main control unit 530.

  Furthermore, when the communication processing unit 560 receives a block information request from the block acquisition processing unit 550, the communication processing unit 560 distributes the block with the block ID corresponding to the file name described in the block information via the communication processing unit 560. Acquired from the unit 100 and responds to the block acquisition processing unit 550.

  Further, a part or all of the functions of each means in the download system based on the access timing control of the present embodiment can be configured by a computer program, and the present invention can be realized by executing the program using the computer. It goes without saying that the procedure in the download method based on the access timing control of the present embodiment can be configured by a computer program, and the program can be executed by the computer. A readable recording medium such as FD (Floppy (registered trademark) Disk), MO (Magneto-Optical disk), ROM (Read Only Memory), memory card, CD (Comp ct Disk) -ROM, DVD (Digital Versatile Disk) -ROM, CD-R, CD-RW, HDD, and recorded in a removable disk, or stored, it is possible to or distribute. It is also possible to provide the above program through a network such as the Internet or electronic mail.

DESCRIPTION OF SYMBOLS 100 ... Content delivery part 200 ... Television broadcasting station part 300 ... Access timing management part 310 ... Setting information management part 320 ... Access control object management part 330 ... Basic parameter calculation part 340 ... Distributed time calculation part 350 ... Block acquisition time calculation part 360 ... Access timing control information update unit 370 ... communication processing unit 380 ... main control unit 400 ... wireless communication station unit 500 ... terminal unit 510 ... broadcast processing unit 520 ... storage unit 530 ... main control unit 540 ... block information management unit 550 ... block acquisition processing 560 ... Communication processing unit

Claims (10)

Content distribution means for distributing a block obtained by dividing a content file into a predetermined size, access timing management means for exchanging information via the content distribution means and a first network, and second contents from the content distribution means Receives information transmitted through a network, and exchanges information with the content distribution unit and the access timing management unit via the first network and a communication network connected to the first network. A system comprising a plurality of terminal devices to perform,
The access timing management means includes
Access timing control information indicating access timing for downloading a block that could not be received via the second network from the content distribution means via the communication network, wherein the terminal device Block number information notification time for notifying the access timing management means of the number of blocks that failed to receive the content file transmitted via the network, and the terminal device receives access timing control information from the access timing management means. A function of managing access control information including an access timing control information acquisition time for acquiring and a block acquisition time for acquiring the block that the terminal device has failed to receive from the content distribution means;
Based on the ID information of each terminal device, the block acquisition overall start time and the block number information notification time notified from the content distribution means, the block number information notification time uniformly distributed to each terminal device; Based on the ID information, access timing control information acquisition start time, and access timing control information acquisition time of each terminal device, the access timing control information acquisition times that are uniformly distributed to each terminal device are calculated. Distributed time calculation means;
The block acquisition time is divided by the number of the terminal devices based on the number of the terminal devices, the ID information of each terminal device, the block acquisition start time, and the block acquisition time permitting download from all the terminal devices to the content. Block acquisition time calculation means for calculating the block acquisition time from
Based on the existing access timing control information, the assumed total number of blocks set assuming the number of blocks notified from each terminal device, the block acquisition start time and the block acquisition time, the block acquisition is performed according to the estimated total number of blocks. An access timing control information updating means for updating the block acquisition time from the divided time and outputting the latest access timing control information;
The content distribution unit acquires the access timing control information from the access timing management unit, and transmits the access timing control information and a block obtained by dividing the content file into a predetermined size via a second network. A function and a function of transmitting the requested acquisition block via the first network and the communication network based on the latest or existing access timing control information managed by the access timing management means. ,
The terminal device
Broadcast processing means for receiving access timing control information and a block of a content file transmitted from the content distribution means via a second network and storing them in a storage means;
Communication processing means for exchanging information with the communication network;
Block information management means for detecting a block that has failed to be received based on the block stored in the storage means, and managing the ID and content file name of the detected block as block information;
By referring to the block number information notification time in the access timing control information stored in the storage means, the total number of block IDs of the block information managed by the block information management means and the content when the corresponding time comes Processing of notifying the access timing management means via the communication processing means as the file name and terminal device ID as block number information;
With reference to the access timing control information acquisition time in the access timing control information stored in the storage means, the access timing control means transmits the access timing control information via the communication processing means when the corresponding time is reached. Processing to acquire the latest access timing control information from the management means, and update the access timing control information stored in the storage means with the acquired information;
Main processing for referring to the block acquisition time in the access timing control information stored in the storage means and issuing a signal for notifying the block information acquired from the block information management means when the corresponding time is reached. Control means;
Upon receipt of the block information issued from the main control means, the content distribution means is accessed via the communication processing means, and the block with the block ID corresponding to the file name described in the block information is obtained. And block acquisition processing means for performing processing to save in the storage means,
A download system based on access timing control. The distributed time calculation means calculates the access timing control information acquisition time based on a sum of a time obtained by multiplying the access timing control information acquisition time by a uniform random number between 0 and 1 and the access timing control information acquisition start time. The download system based on access timing control according to claim 1, wherein: The distributed time calculation means obtains the block number information notification time by the sum of a time obtained by multiplying the block number information notification time by a uniform random number between 0 and 1 and the block acquisition overall start time. 3. A download system based on access timing control according to claim 1 or 2. The access timing control information updating means calculates the unit time width by dividing the block acquisition time by the assumed total number of blocks, acquires the block acquisition time in the existing access timing control information as an initial time, and starts block acquisition The provisional time is obtained by adding the unit time width to the time, provisional time calculation / comparison processing is performed for comparing the provisional time with the initial time, and the provisional time is equal to or greater than the initial time. The provisional time calculation / comparison process is repeated while increasing the unit time width by the time width, and the provisional time when the provisional time is equal to or greater than the initial time is set as the latest block acquisition time in the access timing control information. 4. The download system based on access timing control according to claim 3, wherein the block acquisition time is updated. Content distribution means for distributing a block obtained by dividing a content file into a predetermined size, access timing management means for exchanging information via the content distribution means and a first network, and second contents from the content distribution means Receives information transmitted through a network, and exchanges information with the content distribution unit and the access timing management unit via the first network and a communication network connected to the first network. A plurality of terminal devices to perform,
The access timing management means is access timing control information indicating an access timing for downloading a block that could not be received via the second network from the content distribution means via the communication network, Block number information notification time for notifying the access timing management means of the number of blocks in which the terminal device has failed to receive the content file transmitted via the second network, and the terminal device managing access timing Access control information including an access timing control information acquisition time for acquiring access timing control information from the means and a block acquisition time for acquiring from the content distribution means the block that the terminal device has failed to receive. Sys has the function to manage A download method based on the access timing control in the arm,
Based on the ID information of each terminal device, the block acquisition total start time, and the block number information notification time notified from the content distribution unit, the distributed time calculation unit of the access timing management unit is assigned to each terminal device. The block number information notification time and the terminal device ID information, the access timing control information acquisition start time, and the access timing control information acquisition time are uniformly distributed to the terminal devices. A distributed time calculating step of calculating the access timing control information acquisition time;
The block acquisition time calculation means of the access timing management means is based on the number of the terminal devices, the ID information of each terminal device, the block acquisition start time, and the block acquisition time that allows downloading from all the terminal devices for the content, A block acquisition time calculating step for calculating the block acquisition time from a time obtained by dividing the block acquisition time by the number of the terminal devices;
The access timing control information updating unit of the access timing management unit sets the existing access timing control information, the assumed total number of blocks set assuming the number of blocks notified from each terminal device, the block acquisition start time, and the block acquisition time. An access timing control information update step for updating the block acquisition time from the time obtained by dividing the block acquisition time by the assumed total number of blocks and outputting the latest access timing control information;
A content distribution unit obtains the access timing control information from the access timing management unit, and transmits the access timing control information and a block obtained by dividing the content file into a predetermined size via a second network. When,
A broadcast processing step in which the broadcast processing means of the terminal device receives the access timing control information and the block of the content file transmitted from the content distribution means via the second network and stores them in the storage means;
Block information management in which block information management means of the terminal device detects the block that has failed to be received based on the block stored in the storage means, and manages the ID and content file name of the detected block as block information Steps,
Blocks managed by the block information management unit when the main control unit of the terminal device refers to the block number information notification time in the access timing control information stored in the storage unit and the corresponding time is reached. Notifying the access timing management means through the communication processing means as the block number information of the total number of block IDs of information, content file names and terminal device IDs;
The main control means of the terminal device refers to the access timing control information acquisition time in the access timing control information stored in the storage means, and when the corresponding time is reached, the access timing control information is transmitted to the communication processing means. The access timing management means, and obtaining the latest access timing control information from the management means, and updating the access timing control information stored in the storage means with the acquired information;
The main control means of the terminal device refers to the block acquisition time in the access timing control information stored in the storage means, and notifies the block information acquired from the block information management means when the time comes. Emitting a signal;
The block acquisition processing unit of the terminal device receives the notification of the block information issued from the main control unit, accesses the content distribution unit via the communication processing unit, and sets the file name described in the block information. A block acquisition processing step for performing processing for acquiring a block having a corresponding block ID and storing the block in the storage unit;
A step in which the content distribution means transmits the requested block through the first network and the communication network based on the latest or existing access timing control information managed by the access timing management means; ,
A download method based on access timing control, comprising: The distributed time calculation step includes the access timing control information acquisition time based on a sum of a time obtained by multiplying the access timing control information acquisition time by a uniform random number between 0 and 1 and the access timing control information acquisition start time. The download method based on access timing control according to claim 5, wherein: The distribution time calculating step calculates the block number information notification time by a sum of a time obtained by multiplying the block number information notification time by a uniform random number between 0 and 1 and the block acquisition overall start time. 7. A download method based on access timing control according to claim 5 or 6. The access timing control information update step calculates the unit time width by dividing the block acquisition time by the assumed total number of blocks, acquires the block acquisition time in the existing access timing control information as an initial time, and starts block acquisition The provisional time is obtained by adding the unit time width to the time, provisional time calculation / comparison processing is performed for comparing the provisional time with the initial time, and the provisional time is equal to or greater than the initial time. The provisional time calculation / comparison process is repeated while increasing the unit time width by the time width, and the provisional time when the provisional time is equal to or greater than the initial time is set as the latest block acquisition time in the access timing control information. 8. The download method based on access timing control according to claim 7, wherein the block acquisition time is updated. The download program based on the access timing control which makes a computer function as each means of any one of Claim 1 thru | or 4. The computer-readable recording medium which recorded the download program based on the access timing control of Claim 9.