JP5093274B2 - Terminal device and file transmission system - Google Patents

Description

  The present invention relates to a technique for performing peer-to-peer (P2P) type file transmission between a plurality of terminal devices connected to each other via a network.

  In recent years, various content services using the Internet have been implemented. Such contents are diversified year by year in order to cope with diversification of hobbies and preferences of users who use the contents, and individual contents are also of high quality and large capacity. In addition, the number of Internet connection terminals that use content is increasing. In response to this situation, the load on the server increases as the service scale increases in the conventional client-server method. Therefore, the operation of the content transmission system such as higher performance of the server and securing of sufficient communication bandwidth are required.・ The problem that maintenance costs are enormous is becoming more prominent.

  Therefore, a P2P content transmission system that shares data among a plurality of terminal devices has been put into practical use (see, for example, Patent Document 1). According to such a P2P system content transmission system, it is said that the load on the server that distributes the content can be reduced, and the cost for operation and maintenance can be reduced.

  A karaoke apparatus that provides a karaoke service will be described as an example. In addition to normal performance data (MIDI data), the content played back on a karaoke device includes high-quality live music songs, promotional videos, and commercial videos that sample actual performance sounds. . In addition, in order to provide individual services corresponding to the diversification of tastes and hobbies of users who use karaoke devices, in recent years, content used in karaoke devices is required for each individual user. It is a huge amount.

  For this reason, all the contents that can be provided by the karaoke service cannot be stored in the storage device in each karaoke apparatus. In addition, the conventional method of transmitting content from a large-scale server to a large number of karaoke apparatuses has a problem that the infrastructure cost on the server side becomes enormous. For this reason, a system for transmitting content between the karaoke apparatuses by the P2P method has been used.

  Furthermore, when a terminal device receives a large file such as karaoke content, it divides one file into a number of blocks, acquires a plurality of divided files simultaneously from a plurality of terminal devices, and connects them. File transmission method to obtain the desired file. In this way, even if one of the terminal devices on the transmission side is abnormal or there is a terminal device with an extremely slow transmission speed, the divided file is received from another terminal apparatus with a sufficiently high transmission speed. As a result, files can be acquired more quickly.

JP 2006-197400 A

  An Internet connection terminal such as a karaoke apparatus that performs P2P information communication usually transmits / receives data to / from other terminal apparatuses on the Internet via an access line provided by an Internet service provider (ISP). However, when some terminals transfer a large amount of data by P2P communication, the communication band of the ISP access line is occupied, and there are increasing cases in which communication with other terminal apparatuses is hindered.

In recent years, P2P communication has been actively performed, and this is partly due to an increase in the amount of uplink traffic (at the time of data transmission) of each terminal device, which was not so much conventionally. In order to cope with this, the number of ISPs that perform measures such as limiting the amount of communication data per predetermined period (for example, one day) (especially when sending data) is increasing.
(For example, see http://www.ocn.ne.jp/info/rules/upload/)
In a communication karaoke system that uses P2P communication, if a karaoke device that cannot transmit content occurs due to a conflict with the traffic limit, the number of karaoke devices that can transmit content in the network is reduced accordingly. become. When the number of karaoke devices that can transmit content decreases, content transmission requests are concentrated on the remaining karaoke devices, which may cause delay in content transmission due to an increase in communication load.

  In addition, since the storage capacity of karaoke devices is limited, each karaoke device deletes content with a low holding priority in order to secure storage capacity for acquiring the latest content. Yes. Therefore, there is a bias in the content held by each karaoke device in the network, which is a factor that tends to concentrate content acquisition requests on a specific karaoke device.

  Further, when one content file is divided into a large number and acquired simultaneously from a plurality of karaoke apparatuses, the requests for acquiring the divided files are concentrated on a karaoke terminal having a high transmission speed, and the amount of transmission data tends to reach the upper limit. There is a tendency. This is because while acquiring a divided file from a karaoke device with a low transmission speed, acquisition of the divided file from the karaoke terminal with a high transmission speed ends first, and the next divided file continues to have a high transmission speed. Because it will be obtained from.

  In such a situation, the situation where the number of karaoke apparatuses capable of transmitting content in the network decreases further deteriorates, and if the content transmission is hindered, it is fatal as a karaoke service. Therefore, it is necessary to control so that the transmission data amount of each karaoke apparatus does not exceed the limit value under the condition that the transmission data amount is limited. Such a problem is not limited to a karaoke apparatus, but also applies to various terminal apparatuses that perform P2P file transmission.

  The present invention has been made to solve the above problems, and in a file transmission system that transmits and receives files between terminal devices by P2P communication, control is performed so that the amount of transmission data related to file transmission does not exceed a predetermined upper limit amount. The aim is to provide possible technology.

  The terminal device according to claim 1, which has been made to achieve the above object, is a file among terminal devices constituting a file transmission system that transmits and receives files between a plurality of terminal devices connected to each other via a network. This is a file transmission-side terminal device that transmits a requested file to a request-side terminal device.

  In the present invention, the terminal device on the file request side divides one file into a plurality of blocks that are more than the number of the plurality of terminal devices from which the file is acquired, and a plurality of acquisition destinations. It is assumed that different divided files are acquired from the respective terminal devices in parallel, and the acquisition of the divided files from these terminal devices is repeated until the acquisition of the files is completed.

On the other hand, the terminal device on the file transmission side includes storage means, transmission speed setting means, and transmission means.
The storage means calculates the data amount of the divided file transmitted from the terminal device to the other terminal device during the current period from the upper limit amount of transmittable data set for the terminal device in a predetermined period unit. The reduced amount of remaining data that can be transmitted during the current period is stored. In addition, the predetermined period here may be a period of days such as one day, one week, or one month, or may be a period of time units such as 0 hours.

  The transmission speed setting means decreases the remaining data amount stored in the storage means so that the transmission speed becomes slower than the specified transmission speed and the remaining time until the current period expires. The transmission speed of the divided file is set so that the transmission speed is faster than the specified transmission speed.

  In response to the acquisition request received from the file request side terminal device, the transmission means transmits the divided file corresponding to the acquisition request to the file request side terminal device at the transmission speed set by the transmission speed setting means. To do.

  According to the terminal device on the file transmission side configured in this way, the terminal device with a large amount of remaining data that can be transmitted within a predetermined period has a high data transmission speed, and the terminal device with a small amount of data has a low transmission speed. Be controlled. In a system in which a single file is divided into a large number and a plurality of divided files are acquired in parallel, requests for acquiring the divided files tend to be concentrated on terminals having a high communication speed. Therefore, by reducing the transmission speed of the terminal device whose remaining data amount has decreased, it is possible to distribute divided file acquisition requests to other terminal devices. As a result, even when there are biases among files held among a plurality of terminal devices, it is possible to prevent the amount of transmission data from reaching the upper limit amount due to concentration of acquisition requests only in specific terminal devices. As a result, the amount of transmission data between the terminal devices is smoothed in the entire file transmission system, and the number of terminal devices that can transmit files can be maintained.

  On the other hand, as the remaining time until the current period expires, the transmission speed of the divided file is controlled to increase. By doing in this way, the transmission speed does not become extremely slow in the terminal device with a small remaining data amount just before the update for a predetermined period. Also, if the current period expires and it is updated to the next period, it will be possible to transmit up to the upper limit amount again, so that as much data as possible can be transmitted as quickly as possible within the range not exceeding the upper limit amount within that period. Is desirable. For this purpose, control for reducing the remaining time and increasing the transmission speed is effective.

  Further, as described in claim 2, it is preferable that the remaining data amount stored in the storage means is reset to the upper limit amount when the predetermined period has expired (reset means). For example, if an upper limit is set for the amount of data that can be sent in one day, if the date is updated, the data amount from 0 to the upper limit will be sent on the next day regardless of the amount of data sent up to the previous day. Will be accepted. Therefore, the remaining data amount that can be transmitted can be appropriately managed by resetting the remaining data amount to the upper limit upon expiration of a predetermined period (for example, date unit or time unit).

Further, as described in claim 3, or the total data size of the divided files transmitted during the current period when it reaches the upper limit amount, and configured not to transmit the divided file. With this configuration, it is possible to prevent transmission of the divided file in a state where the upper limit amount is exceeded.

  Next, a file transmission system according to claim 4 is a file in which the file request side terminal device according to claim 1 and a plurality of terminal devices having file transmission side functions are connected to each other via a network. It is a transmission system. According to this file transmission system, the above-described effects can be obtained.

1 is a block diagram showing a schematic configuration of a file transmission system 1. FIG. It is explanatory drawing which shows typically the mode of the file transmission by P2P. It is explanatory drawing which shows the division | segmentation acquisition method of a file typically. It is a flowchart figure which shows the procedure of a file acquisition process. It is a flowchart figure which shows the procedure of a file transmission process. It is explanatory drawing which shows the example of calculation of transmission speed.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In addition, this invention is not limited to the following embodiment at all, and can be implemented in various aspects.
[Description of Configuration of File Transmission System 1]
As shown in FIG. 1A, the file transmission system 1 is formed by connecting a plurality of terminal devices 4a, 4b, 4c, 4d, and 4e to each other via the Internet 200 so that they can communicate with each other. In the following description, the terminal devices 4a, 4b, 4c, 4d, and 4e are simply expressed as the terminal device 4 unless otherwise distinguished. 1 shows a configuration in which five terminal devices 4 are connected to the file transmission system 1 for convenience of explanation, more terminal devices 4 may be connected.

  The file transmission system 1 is a P2P network system that can share files by transmitting and receiving files such as contents between the terminal devices 4 that are Internet connection terminals. Moreover, in this embodiment, regarding the transmission / reception of files between the terminal devices 4, an upper limit is provided for the transmission data amount of the files that can be transmitted by each terminal device 4 per predetermined period (for example, the number of days or the time unit). Assumes that. This is a measure for preventing the communication bandwidth of the public line from being occupied due to an excessive amount of data transmitted by each terminal device 4. Therefore, each terminal device 4 has a remaining data amount of a file that can be transmitted to another terminal device 4 during the current period (the amount of data of a file transmitted during the period from the upper limit amount of the transmission data amount for each period). Is stored and managed.

  The terminal device 4 is an information processing device that stores files such as contents used by the user in its own HDD 44 and executes various processes by reading the stored files. Each terminal device 4 is assigned a unique serial number (for example, a manufacturing number) and an IP address as identification information for identifying a device that transmits and receives data.

  The terminal device 4 includes an HDD 44 that is a storage device for holding a file to be executed by itself. The storage capacity of the HDD 44 is small enough to hold all the files distributed in the file transmission system 1. . Therefore, each terminal device 4 has only a part of files. Therefore, by sharing the file among the plurality of terminal devices 4 connected to the file transmission system 1, all the files can be used in each terminal device 4.

  Specifically, the terminal device 4 is a divided file unit obtained by dividing one file into a plurality of blocks, and a client function that simultaneously acquires a file from a plurality of terminal devices 4 (servers), and another terminal device 4 (client) and a server function for transmitting a divided file corresponding to the request in response to the divided file acquisition request. Detailed contents of processing by these client functions and server functions will be described later.

Next, FIG. 1B is a block diagram illustrating a schematic configuration of the terminal device 4.
The terminal device 4 includes a CPU 41, a RAM 42, a ROM 43, an HDD 44, an operation unit 45, a network communication unit 46, and the like as a hardware configuration.

  Among these, the CPU 41 is a device that executes control and various operations for each part of the terminal device 4 in accordance with programs and data stored in the RAM 42 and the ROM 43, and various processes related to client functions and server functions described later are executed by the CPU 41. The The RAM 42 is a storage device used as a main memory or the like that is directly accessed from the CPU 41. The remaining data amount of the terminal device 4 is stored in the RAM 42. The ROM 43 is a nonvolatile storage device, and stores BIOS, read-only data that is not normally updated, and the like. The HDD 44 is a device for storing various data such as files and programs related to various contents. The operation unit 45 is an input device for inputting various instructions from the user, and includes a plurality of key switches and the like. The network communication unit 46 is a communication interface for connecting the terminal device 4 to the Internet 200 and communicating with the outside.

[Explanation of file division acquisition]
Next, the communication status between the terminal devices 4 in the file communication system 1 will be described with reference to FIG.

  FIG. 2A shows an example in which the terminal device 4a acquires the file A as a client. In this example, the terminal device 4a simultaneously acquires the file A from the three terminal devices 4c, 4d, and 4e (servers) that hold the file A. At this time, the terminal device 4a simultaneously divides each divided file from each server in parallel in units of divided files obtained by dividing the file A into a larger number of blocks than the number of three servers from which the file is acquired. get. Then, every time acquisition of one divided file is completed, acquisition of the next divided file is started from the free server, and this operation is repeated until acquisition of all the divided files constituting the file A is completed.

  FIG. 2B shows a case where the terminal device 4a acquires the file A and then the terminal device 4b acquires the file A as a client. The terminal device 4b acquires the file A from the three terminal devices 4a, 4d, and 4e (servers) that hold the file A at the same time. In this case, since the terminal device 4a, which was a client in FIG. 2A, has the file A, it now functions as a server on the side that transmits the file A. The terminal device 4b acquires different divided files from each server in parallel in divided file units obtained by dividing the file A into a larger number of blocks than the number of three servers from which the file is acquired. Then, every time acquisition of one divided file is completed, acquisition of the next divided file is started from the free server, and this operation is repeated until acquisition of all the divided files constituting the file A is completed.

  Next, the relationship between the transmission speed of the terminal device 4 on the server side that transmits the divided file and the number of transmission blocks will be described with reference to FIG. In FIG. 3, the client side terminal device 4 obtains a divided file of file A from three servers (terminal devices 4 c, 4 d, 4 e) simultaneously in parallel. It is modeled by the image that fills sequentially with blocks. Each block is an individual divided file of the file A. For convenience of explanation, the hatching pattern of the blocks shown in the figure is changed for each transmission source of the divided files. In the example shown in FIG. 3, it is assumed that the terminal device 4d is the fastest, and then the terminal device 4e and the terminal device 4c are the slowest, regarding the data transmission speed of each terminal device 4 on the server side.

  The stage in FIG. 3A is a stage in which file A divisional acquisition is started simultaneously from three servers. At this stage, the client is in the process of acquiring the first divided file from each of the three servers. Eventually, as shown in FIG. 3 (b), when reception of the divided file from the terminal device 4d (communication speed: highest speed) ends first, acquisition of the next divided file from the terminal device 4d is started immediately. . In this way, by repeating the operation of starting acquisition of the next divided file sequentially from the server that has acquired one divided file from among the plurality of servers that acquire the divided file in parallel, Get the split files one after another from the server. Therefore, when the transmission speeds of the servers are different from each other, a difference occurs in the number of divided file blocks to be transmitted, that is, the amount of transmission data.

  Then, as shown in FIG. 3C, when the reception of the 14th divided file is reached, the number of transmission blocks of the terminal device 4c is 2, the number of transmission blocks of the terminal device 4d is 8, and the transmission of the terminal device 4e. The number of blocks is 4. This number is only an example, but if the file is large, there is a possibility that there will be a considerable difference in the amount of data transmitted by each server due to the difference in transmission speed. Thus, there is a tendency that divided file transmission requests are concentrated on the terminal device 4 having a high communication speed, and if the communication speed at the time of transmitting the divided file is not adjusted at all, the amount of transmission data within a predetermined period is increased. It is easy to reach the upper limit. In order to avoid such a situation, the terminal device 4 of the present embodiment has a function of adjusting the transmission speed at the time of divided file transmission according to the remaining data amount and the remaining time of the predetermined period.

[Description of client processing]
Next, processing executed by the terminal device 4 as a client function will be described with reference to FIG.

  FIG. 4 is a flowchart illustrating a procedure of client processing executed by the CPU 41 of the terminal device 4. This process is a process executed when a user gives an instruction to acquire a file.

  In S100, the CPU 41 of the terminal device 4 searches the network for the terminal device 4 that is the transmission source (server) of the file to be acquired. Then, a predetermined number n of source terminal devices 4 are determined from the retrieved candidates (S101). In addition, as a method of determining the terminal device 4 that is a file transmission source, for example, there are methods described in (1) to (3) below.

  (1) Each terminal device 4 participating in the file transmission system 1 and a management device (not shown) for centrally storing and managing a list of files held by each terminal device 4 are provided on the Internet 200. deep. The client terminal device 4 requesting the file acquisition inquires of the management device about the location (IP address or the like) of the terminal device 4 that holds the file to be acquired on the network. The management device notifies the client terminal device 4 of the IP addresses of the transmission sources 1 to n corresponding to the inquiry from the stored terminal devices 4. Based on the notification from the management device, the client terminal device 4 determines the terminal device 4 to be the file transmission source.

  (2) Each terminal device 4 participating in the file transmission system 1 associates the location of the file with a file name and identification information (serial number, IP address, etc.) of the terminal device 4 that holds the file. You may memorize | store in each memory | storage means as a table. In this case, the client-side terminal device 4 extracts the file transmission sources 1 to n by extracting the IP address and the like of the terminal device 4 that holds the file to be acquired from the table stored in the terminal device 4 itself. Searchable. The client terminal device 4 determines the terminal device 4 to be a file transmission source based on the search result from this table.

(3) The server of the transmission source can be determined using the search method described in paragraphs [0062] to [0068] of Patent Document 1.
Since the methods (1) to (3) are all known, a detailed description or the like is not shown.

  Returning to the flowchart of FIG. Subsequently, in the loop processing of S102 to S104, the loop processing for n units is simultaneously executed in parallel for each of the predetermined number n of transmission source terminal devices 4 determined in S101.

  In S102, the terminal device 4 that is the transmission target of the communication target is requested to transmit an unreceived block among the divided files obtained by dividing the file to be acquired into a larger number of blocks than the number n of the transmission source servers. . Next, in S103, the block data transmitted from the transmission source terminal device 4 is received in response to the request. After completion of reception of block data, it is determined whether or not acquisition of all blocks is complete (S104). If there is an unreceived block as a result of the determination (S104: NO), the process returns to S102, and the terminal device 4 of the same transmission source is requested to transmit an unreceived block again. On the other hand, when acquisition of all the blocks has been completed (S104: YES), the loop processing ends.

[Description of server processing]
Next, processing executed by the terminal device 4 as a server function will be described with reference to FIGS.

FIG. 5 is a flowchart illustrating a server process executed by the CPU 41 of the terminal device 4. This process is a process that is always executed while the terminal device 4 is in operation.
First, in S200, the CPU 41 of the terminal device 4 initializes the remaining data amount stored in a predetermined area of the RAM 42 to an upper limit amount for each predetermined period (here, assumed to be one day). Next, it is determined whether or not there is a split file transmission request from the client side terminal device 4 (S201). If a split file transmission request is not received from the client side terminal device 4 (S201: NO), this process is repeated.

  When a divided file transmission request is received from the client side terminal device 4 (S201: YES), it is determined whether or not the date has been updated since the last time the divided file was transmitted (S202). As a result of the determination, if the date has not been updated (S202: NO), the process proceeds to S204. On the other hand, if the date is updated (S202: YES), the remaining data amount stored in the predetermined area of the RAM 42 is reset to the upper limit amount for one day (S203), and the process proceeds to S204.

In S204, the transmission speed (β) for transmitting the divided file is calculated. The transmission speed (β) is calculated by the following equation, where α is a prescribed communication speed.
β = α × (remaining data amount ÷ upper limit amount) × (time length of the specified period ÷ remaining time of the current period)
According to the above formula, as the ratio of the remaining data amount to the upper limit amount in a predetermined period unit becomes smaller, the transmission rate (β) becomes slower than the specified transmission rate (α), and the current period expires. As the remaining time until becomes shorter, the transmission speed (β) becomes higher than the prescribed transmission speed (α). Also, in the above formula, when the predetermined period is one day and the elapsed time of the day is measured in seconds, the communication speed (β) is calculated by the following formula with the elapsed seconds since the date is updated as now. be able to.
β = α × (remaining data amount ÷ upper limit amount) × (86400 ÷ (86400−now))
Subsequently, in S205, the requested divided file is transmitted to the client terminal device 4 at the transmission speed (β) calculated in S204. However, if the total data amount of the divided files transmitted during the day has reached the upper limit of one day, that is, if the remaining data amount is 0, no further divided files are transmitted.

  After the transmission of the divided file is completed, it is determined whether or not the date is updated during the transmission of the divided file (S206). As a result of the determination, if the date is updated during transmission (S206: YES), the remaining data amount stored in the predetermined area of the RAM 42 is reset to the upper limit amount for one day (S207). Subsequently, the transmission data amount transmitted after the date change is subtracted from the remaining data amount in the data amount of the transmitted divided file (S208), and the process returns to S201. On the other hand, if the date has not been updated during transmission of the divided file (S206: NO), the data amount of the divided file transmitted this time is subtracted from the remaining data amount (S209), and the processing returns to S201.

  In the embodiment shown in the flowchart of FIG. 5, the example in which the predetermined period is assumed to be one day has been described. However, the predetermined period is not limited to one day and may be set for a plurality of days or time units. In that case, in the above-described S201 and S206, instead of determining whether to update the date, the expiration of the predetermined period (determination of a predetermined number of days or time) is determined.

  FIG. 6 is an explanatory diagram illustrating a calculation example of the transmission speed (β) when the terminal device 4 on the server side transmits the divided file. Here, as shown in FIG. 6 <a>, the upper limit amount of the daily transmission data amount is set, and the communication speed (β) when the elapsed time (now) of the day is measured in seconds is calculated. The case is assumed. In addition, it is assumed that the upper limit amount of the daily transmission data amount is 48 Gbytes and the prescribed transmission speed (α) is 10 Mbps.

  In the case shown in (b1) of FIG. 6, the remaining data amount is 24 Gbytes (50% of the upper limit amount) when 12 hours (50% of the predetermined period) have elapsed since the date update. In this case, the coefficient of the remaining data amount with respect to the specified transmission speed (α) is 0.5, but the coefficient of the remaining time is 2, and as a result, the communication speed (β) becomes the specified transmission speed (α ) Equal to 10 Mbps.

  In the case shown in (b2) of FIG. 6, the remaining data amount is 36 Gbytes (75% of the upper limit amount) when 12 hours (50% of the predetermined period) have passed since the date update. This remaining data amount is larger than the above-mentioned case (b1). In this case, since the coefficient of the remaining data amount with respect to the specified transmission speed (α) is 0.75 and the coefficient of the remaining time is 2, as a result, the communication speed (β) is 1 of the specified transmission speed (α). It becomes 15 Mbps corresponding to .5 times. Thus, when the ratio of the remaining data amount is large with respect to the ratio of the remaining time, the communication speed is increased.

  In the case shown in (b3) of FIG. 6, the remaining data amount is 12 Gbytes (25% of the upper limit amount) when 12 hours (50% of the predetermined period) have passed since the date update. This remaining data amount is smaller than the above-mentioned case (b1). In this case, the coefficient of the remaining data amount with respect to the specified transmission speed (α) is 0.25, and the coefficient of the remaining time is 2, so that the communication speed (β) is 0 of the specified transmission speed (α). It becomes 5 Mbps corresponding to 5 times. As described above, when the ratio of the remaining data amount is small with respect to the ratio of the remaining time, the communication speed is reduced.

  In the case shown in (b4) of FIG. 6, when 18 hours (75% of the predetermined period) have passed since the date update, the remaining data amount is 12 Gbytes (25% of the upper limit amount), and the above-described (b1 ), The remaining data volume and remaining time are both smaller. In this case, since the coefficient of the remaining data amount with respect to the specified transmission rate (α) is 0.25 and the coefficient of the remaining time is 4, as a result, the communication speed (β) is equal to the specified transmission rate (α). 10 Mbps. Thus, even if the remaining data amount becomes small, the communication speed is maintained if the remaining time of the period decreases.

[Correspondence with configuration described in claims]
The correspondence between the configuration of the file transmission system 1 according to the embodiment and the configuration described in the claims is as follows. The CPU 41 of the terminal device 4 corresponds to a transmission speed setting unit, a transmission unit, a reset unit, and a file acquisition unit in the claims, and the RAM 42 corresponds to a storage unit.

[effect]
According to the file transmission system 1 of the above embodiment, the following effects can be obtained.
(1) In a system in which one file is divided into a large number and a plurality of divided files are acquired in parallel, requests for acquiring the divided files tend to be concentrated on terminals having a high communication speed. Therefore, by reducing the transmission speed of the terminal device 4 on the server side where the remaining data amount has decreased, the divided file acquisition requests can be distributed to the other terminal devices 4. As a result, even when the files held among the plurality of terminal devices 4 are biased, it is possible to prevent the acquisition requests from being concentrated only on the specific terminal device 4 and the transmission data amount from reaching the upper limit amount. As a result, the amount of transmission data between the terminal devices 4 is smoothed in the entire file transmission system 1, and the number of terminal devices 4 that can transmit files can be maintained.

  Further, by controlling so that the transmission speed of the divided file becomes faster as the remaining time until the current period expires, the transmission speed immediately before the update of the predetermined period in the terminal device 4 with a small remaining data amount Will not be extremely slow. Furthermore, if the current period expires and it is updated to the next period, it will be possible to transmit again up to the upper limit amount, so that as much data as possible can be transmitted as quickly as possible without exceeding the upper limit amount within that period. Is desirable. For this purpose, control for reducing the remaining time and increasing the transmission speed is effective.

  (2) For example, when the upper limit of the data amount that can be transmitted in one day is set, if the date is updated, the data amount from 0 to the upper limit value on the next day regardless of the data amount transmitted up to the previous day Will be accepted. Therefore, the remaining data amount that can be transmitted can be appropriately managed by resetting the remaining data amount to the upper limit upon expiration of a predetermined period (for example, date unit or time unit).

  (3) In the terminal device 4 on the server side, when the total data amount of the divided files transmitted during the current period reaches the upper limit amount, the upper limit amount is exceeded by configuring so that no further divided files are transmitted. You can prevent split files from being sent in a live state.

  DESCRIPTION OF SYMBOLS 1 ... File transmission system, 4 ... Terminal device, 41 ... CPU, 42 ... RAM, 43 ... ROM, 44 ... HDD, 45 ... Operation part, 46 ... Network communication part, 200 ... Internet.

Claims (4)

Among the plurality of terminal devices that constitute a file transmission system in which a plurality of terminal devices are connected to each other via a network and transmit and receive files between the plurality of terminal devices,
In a divided file unit in which one file is divided into a plurality of blocks larger than the number of the plurality of terminal devices from which the file is acquired, separate divided files are simultaneously and simultaneously from the plurality of terminal devices from which the file is acquired The terminal device on the file transmission side that transmits the requested divided file to the terminal device on the file request side that repeats the acquisition of the divided file from those terminal devices until acquisition of the file is completed. Because
From the upper limit amount of transmittable data set for the terminal device in units of a predetermined period, the data amount of the divided file transmitted to the other terminal device by the own terminal device during the current period is reduced. Storage means for storing the remaining amount of data that can be transmitted during this period;
The smaller the amount of remaining data stored in the storage means, the slower the transmission rate with respect to the prescribed transmission rate, and the smaller the remaining time until the current period expires, Transmission speed setting means for setting the transmission speed of the divided file so that the transmission speed is higher than the transmission speed of
In response to an acquisition request received from the file requesting terminal device, a transmission for transmitting the divided file corresponding to the acquisition request to the file requesting terminal device at the transmission speed set by the transmission speed setting means A terminal device. The terminal device according to claim 1,
The terminal device further comprising a reset unit that resets the remaining data amount stored in the storage unit to the upper limit when the predetermined period expires. In the terminal device according to claim 1 or 2,
It said transmission means, if the total data size of the divided files transmitted during the current period has reached the upper limit amount, the terminal apparatus characterized by not sending the split files.
A file transmission system in which a plurality of terminal devices are connected to each other via a network and transmit / receive a file between the plurality of terminal devices,
The terminal device
As a means for obtaining files,
In a divided file unit in which one file is divided into a plurality of blocks larger than the number of the plurality of terminal devices from which the file is acquired, separate divided files are simultaneously and simultaneously from the plurality of terminal devices from which the file is acquired. File acquisition means for repeatedly acquiring the divided file from those terminal devices until the acquisition of the file is completed,
As a means for sending files,
From the upper limit amount of transmittable data set for the terminal device in units of a predetermined period, the data amount of the divided file transmitted to the other terminal device by the own terminal device during the current period is reduced. Storage means for storing the remaining amount of data that can be transmitted during this period;
The smaller the amount of remaining data stored in the storage means, the slower the transmission rate with respect to the prescribed transmission rate, and the smaller the remaining time until the current period expires, Transmission speed setting means for setting the transmission speed of the divided file so that the transmission speed is higher than the transmission speed of
In response to the divided file acquisition request received from the terminal device on the file request side, the divided file corresponding to the acquisition request is transmitted to the terminal device on the file request side at the transmission speed set by the transmission speed setting means. A file transmission system.