JP2010062720A - Communication terminal, communication system, available band estimating method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a communication terminal that estimates an available bandwidth while taking an effect of simultaneous use of a network by a plurality of applications into consideration even in such a case. <P>SOLUTION: A communication application means 111 achieves communication with a communication partner. A network transmission and reception means 113 is used in common by a plurality of applications using the network. An integrated band estimating means 115 acquires data communication information on data that the network transmitting and receiving means 113 receives from the communication partner during the execution of a plurality of applications. The integrated band estimating means 115 estimates an available band for a communication terminal 10 of the communication partner based upon the data communication information in a predetermined period. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a communication terminal and a communication system, and more particularly to a communication terminal and a communication system capable of simultaneously executing a plurality of applications using a network including one or more communication applications. The present invention also relates to an available bandwidth estimation method, a communication quality control method, and a program in such a communication terminal.

  Due to the low cost of broadband communication lines, intranet / Internet communication has evolved from traditional voice calls to advanced communications that combine videophones, whiteboards for collaborative work, and data sharing applications such as document sharing. . In such a communication environment, it is possible to communicate while simultaneously using a plurality of applications, such as drawing on a shared whiteboard while talking on a videophone, and sending materials by file transfer as necessary.

  In the advanced communication environment, when the number of applications simultaneously used increases, the bandwidth required for communication increases accordingly. Even in a wide band, in an environment where a finite band is shared for various purposes, the bandwidth that can be used for communication is finite, and when one application uses more bandwidth, other applications can use it. Bandwidth decreases. If an application attempts to transmit data beyond the available bandwidth, data loss during communication, and associated retransmission and delay will occur. Data loss and delay lead to degradation of communication quality such as sound quality / image quality degradation and delay of response to operation. For this reason, in order to maintain the communication quality, it is indispensable to estimate the available bandwidth and perform data transmission according to it.

Patent Document 1 describes an example of a technique for estimating available bandwidth and performing communication based on the estimated bandwidth. FIG. 10 shows a communication system in Patent Document 1. The server 301 has a transmission control unit 302 and a data transmission unit 303. The portable wireless terminal 310 has a reception control unit 311 and a data reception unit 312. The data reception unit 312 notifies the reception control unit 311 of the data reception status, for example, the number of packet errors, the bit error rate, and the received electric field strength. The reception control unit 311 calculates the current transmission rate (bandwidth) and notifies the transmission control unit 302 of it. The transmission control unit 302 controls the data transmission unit 303 to change the transmission rate and the compression rate according to the transmission rate.
Republished patent WO2002 / 032082

  A problem in the technique described in Patent Document 1 is that the bandwidth cannot be estimated correctly when a plurality of applications simultaneously use the network. The reason is that, in a shared network, the mutual influence of simultaneous communication is ignored and band estimation is performed independently for each application.

  The present invention relates to a communication terminal, a communication system, an available bandwidth estimation method, a communication quality control method, and a program capable of estimating an available bandwidth in consideration of the influence even when a plurality of applications use the network simultaneously. The purpose is to provide.

  In order to achieve the above object, the communication terminal of the present invention can simultaneously execute a plurality of applications using a network including one or more communication applications, and can execute communication with a communication partner by executing the communication application. A communication terminal that performs communication, and is commonly used for a plurality of applications that use the network, and transmits and receives data of the application, and the network during execution of the plurality of applications that use the network The communication means acquires data communication information including a data amount and communication time information of data received from a communication partner, and based on the data communication information in a predetermined period, the communication Characterized in that it comprises a integrated bandwidth estimation means for estimating the available bandwidth between the communication terminal ® down opponent.

  The communication system of the present invention is capable of simultaneously executing a plurality of applications using a network including one or more communication applications on a terminal, and performing communication with a communication partner by executing the communication application. A system that is commonly used for a plurality of applications that use the network during execution of a plurality of applications that use the network, and that is used by a network transmission / reception unit that transmits and receives data of the application. Data communication information including data volume and communication time information is acquired, and based on the data communication information in a predetermined period, an available band with the communication terminal of the communication partner And receiving the estimation result of the available band transmitted by the integrated band estimation unit, and based on the estimation result of the available band, And a transmission terminal having integrated transmission control means for controlling data transmission of the application.

  The available bandwidth estimation method of the present invention is capable of simultaneously executing a plurality of applications using a network including one or more communication applications, and performing communication with a communication partner by executing the communication application. The method of estimating an available bandwidth in the method, wherein the communication terminal is commonly used for a plurality of applications using the network and transmits / receives data of the application during execution of the plurality of applications using the network A step of acquiring data communication information including a data amount and communication time information of data received by a network transmitting / receiving means from a communication partner; and Based on, characterized in that a step of estimating the available bandwidth between the communication terminal of the communication partner.

  The communication quality control method of the present invention is capable of simultaneously executing a plurality of applications using a network including one or more communication applications, and performing communication with a communication partner by executing the communication application. A communication quality control method, wherein the communication terminal is commonly used for a plurality of applications that use the network, and a plurality of applications that use the network are executed from a network transmission / reception unit that transmits and receives data of the application A step of acquiring data communication information including a data amount and communication time information of data received by the network transmission / reception means from a communication partner; and Estimating the available bandwidth with the communication partner communication terminal based on the data communication information, and the communication terminal controls data transmission of the application based on the estimation result of the available bandwidth And a step of performing.

  The program of the present invention is capable of simultaneously executing a plurality of applications using a network, and executing a process of estimating an available bandwidth at a communication terminal that communicates with a communication partner by executing the communication application. A program for causing the communication terminal to be commonly used for a plurality of applications that use the network, and from a network transmitting / receiving unit that transmits and receives data of the application, during execution of the plurality of applications that use the network, The network transmitting / receiving means acquires the data communication information including the data amount and communication time information of the data received from the communication partner, and the communication based on the data communication information in a predetermined period. Characterized in that to execute a process of estimating the available bandwidth between the communication terminal of application partners.

  The communication terminal, the communication system, the usable bandwidth estimation method, the communication quality control method, and the program according to the present invention estimate the usable bandwidth in consideration of the influence even when a plurality of applications use the network at the same time. be able to.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 shows a communication apparatus according to a first embodiment of the present invention. The terminal device (communication terminal) 10 includes a data processing device 11 and a storage device 12. The data processing apparatus 11 includes a plurality of communication application units 111 (111A to 111C), a network transmission / reception unit 113, an integrated transmission control unit 114, and an integrated band estimation unit 115. The storage device 12 includes a band estimation method storage unit 121 and a transmission method storage unit 122. The function of each means in the data processing device 11 can be realized by the data processing device operating according to a predetermined program.

  The communication terminal 10 realizes communication between users who use the communication terminal 10 by communicating with other communication terminals 10. The communication terminals 10 may communicate directly with each other, or may communicate using some kind of relay device. On the communication terminal 10, a plurality of communication application means used by the user for communication can be executed simultaneously. FIG. 1 shows a state in which three communication application units 111A to 111C are being executed.

  Each communication application unit 111 performs input / output to / from the user, transmission / reception of data to / from a communication partner communication terminal, and data processing specific to the application. The network transmission / reception unit 113 is a shared communication unit in the terminal, and is used in common by the plurality of communication application units 111. Each communication application unit 111 transmits data to the communication partner via the network transmission / reception unit 113. Each communication application unit 111 receives data from a communication partner via the network transmission / reception unit 113. Each communication application means 111 processes received data and outputs it as necessary.

  When the network transmission / reception unit 113 receives the data of the communication application unit 111, the network transmission / reception unit 113 stores data communication information related to the received data in a storage unit (not shown). The data communication information includes the data amount of the communication application unit 111 received by the network transmission / reception unit 113 and communication time information. The communication time information includes time information regarding data transmission at the transmitting terminal and time information regarding data reception at the receiving side. As the time information related to data transmission at the transmission terminal, a data transmission time, a set of a data transmission start time and a data transmission end time, or the like can be considered. As the time information related to data reception, a data reception time, a set of a data reception start time and a data reception end time, or the like can be considered. The time information regarding the data transmission is given by the network transmission / reception means 113 of the transmitting terminal, and is transmitted to the receiving communication terminal 10 together with the data.

  The integrated band estimation unit 115 collects data communication information from the network transmission / reception unit 113 during execution of the plurality of communication application units 111. The integrated band estimation means 115 estimates the available bandwidth (data throughput per unit time) between the two communication terminals 10 in communication using the collected data communication information. At this time, the integrated band estimation means 115 estimates an available band based on the data communication information in a predetermined period.

  For example, when the two communication application units 111 receive data during a predetermined period, the integrated band estimation unit 115 stores data communication information about the data received by the two communication application units 111 on the network. Receive from the transmission / reception means 113. By estimating the available bandwidth using the received data communication information within a predetermined period, when a plurality of applications use the network at the same time, it is possible to estimate the available bandwidth in consideration of the mutual influence.

  When the integrated band estimation unit 115 estimates the available band, the integrated band estimation unit 115 transmits the estimation result to the integrated transmission control unit 114 of the communication partner communication terminal 10. When the integrated transmission control unit 114 receives the estimation result of the available band, the integrated transmission control unit 114 determines the data transmission method in the network transmission / reception unit 113 using the estimation result of the available band. The integrated transmission control unit 114 instructs the network transmission / reception unit 113 on the determined data transmission method. Upon receiving the instruction, the network transmission / reception means 113 controls the data transmission of each communication application means 111 so that the communication quality is improved according to the instruction. The integrated transmission control means 114 controls the communication quality by instructing the network transmission / reception means 113 about the data transmission method.

  Note that the bandwidth estimation method in the integrated bandwidth estimation means 115 may always be the same estimation method, or an appropriate one is selected from the bandwidth estimation method storage unit 121 according to the type and number of applications being executed and the communication method. However, the estimation method may be changed according to the situation. Also, the transmission control in the integrated transmission control unit 114 may always be the same control method, or an appropriate control method from the transmission method storage unit 122 according to the type and number of applications being executed and the usage method of the user. The control method may be changed according to the situation. The integrated transmission control unit 114 may perform transmission control using the available band estimated by the integrated band estimation unit 115 in its own device when there is no significant difference between the uplink and the downlink. Good.

  FIG. 2 shows communication between the communication terminals 10 during communication. In FIG. 2, for convenience, the communication terminal 10X is a transmission terminal and the communication terminal 10Y is a reception terminal. When the communication is bidirectional, the communication terminals 10X and 10Y serve as both a transmission terminal and a reception terminal. The transmission terminal 10X and the reception terminal 10Y are connected via a network and constitute a communication system. In FIG. 2, some of the components of the communication terminal 10 are omitted. As for the application, only the application A describes constituent elements in detail. The applications B and C have the same configuration as that of the application A.

  Corresponding applications communicate with each other between the transmitting terminal 10X and the receiving terminal 10Y. The communication application unit 111 of the transmission terminal 10X transmits data according to the processing to the reception terminal 10Y via the network transmission / reception unit 113. The communication application unit 111 of the receiving terminal 10Y receives the data transmitted by the communication application unit 111 of the transmitting terminal 10X via the network transmitting / receiving unit 113. As other communication, the integrated band estimation means 115 of the receiving terminal 10Y transmits the estimation result of the available band to the integrated transmission control means 114 of the transmission terminal 10X via the network transmission / reception means 113.

  FIG. 3 shows an operation procedure at the time of data reception. Between the communication terminals 10 that perform communication, data of various communication application means 111 is transmitted and received between the network transmission / reception means 113 of both terminals in accordance with user operations. When receiving data (step S11), the network transmission / reception means 113 records data communication information related to the received data (step S12). The data communication information includes a received data amount, a transmission time, and a reception time. The transmission time is given to the transmission data by the network transmission / reception means 113 of the communication partner at the time of data transmission. The network transmission / reception means 113 records and accumulates data communication information every time data is received.

  FIG. 4 shows an operation procedure during transmission control. The integrated band estimation means 115 requests the network transmission / reception means 113 to provide data communication information periodically at predetermined time intervals. The network transmission / reception unit 113 provides the data communication information accumulated from the previous request to the current request to the integrated band estimation unit 115 (step S21). The network transmission / reception unit 113 may provide data communication information to the integrated band estimation unit 115 every time data is received, and the integrated band estimation unit 115 may store the data communication information. After providing the data communication information, the network transmission / reception means 113 deletes the stored information and newly starts storing data communication information.

  The integrated band estimation unit 115 estimates the data throughput per unit time from the communication terminal 10 of the communication partner to the own terminal by combining the acquired data communication information in a predetermined period, and uses this as the estimated available bandwidth ( Step S22). After estimating the bandwidth, the integrated band estimation unit 115 transmits the estimated available bandwidth information to the integrated transmission control unit 114 of the communication terminal 10 of the communication partner via the network transmission / reception unit 113 (step S23). The integrated band estimation unit 115 may transmit the estimated available bandwidth information only when the difference from the previous estimated available bandwidth is a certain value or more. Alternatively, the integrated bandwidth estimation unit 115 may transmit the estimated available bandwidth only when the estimated available bandwidth is equal to or less than a predetermined threshold.

  The integrated transmission control means 114 of the communication terminal 10 of the communication partner receives the estimated available bandwidth information via the network transmission / reception means 113. Based on the received available bandwidth information, the integrated transmission control unit 114 determines the data transmission method of each communication application unit 111 being executed so that the total transmission data amount falls within the estimated available bandwidth, and transmits / receives the network. The means 113 is instructed (step S24). The network transmission / reception means 113 transmits the data from each communication application means 111 according to the instruction content (step S25). The instruction content may be, for example, “communication application A transmits at 200 kbps” or “transmits so that the sum of communication applications B and C is 1 Mbps”.

  For example, it is assumed that the communication application unit 111A and the communication application unit 111B receive data twice each within a predetermined period. The network transmission / reception means 113 records and stores the data communication information of the data received by the communication application means 111A and the data communication information of the data received by the communication application means 111B.

  The network transmission / reception means 113 provides a total of four data communication information accumulated during a predetermined period to the integrated band estimation means 115. The integrated band estimation means 115 estimates the available band with the communication terminal 10 of the communication partner by combining the received four data communication information. The available bandwidth can be obtained from the time when data was flowing and the amount of data (received data amount) flowing at that time.

  In the present embodiment, the integrated band estimation unit 115 acquires data communication information from a network transmission / reception unit that is used in common for a plurality of communication applications, and estimates an available band based on the data communication information in a predetermined period. . When there are a plurality of types of communication applications that have received data during a predetermined period, the integrated band estimation unit 115 estimates the available band by using data communication information regarding the plurality of communication applications. In the present embodiment, the communication status of each communication application in a predetermined period is aggregated, and the communication band is estimated using the result of centrally measuring the communication status. For this reason, even when a plurality of applications use the network at the same time, it is possible to estimate the use band in consideration of the influence.

  Here, in the technique described in Patent Document 1, estimation of a band is performed when each application performs communication. For this reason, in Patent Document 1, an application with low communication frequency can only be controlled based on the estimated bandwidth when communication was performed previously, and cannot follow the fluctuation of the available communication bandwidth. In the present embodiment, even when there is an application with low communication frequency, it is possible to perform data transmission control based on the estimation result of the available bandwidth using the data communication information of another communication application being executed. Therefore, transmission control can be performed for applications with low communication frequency following changes in the communication band.

  FIG. 5 shows a communication terminal according to the second embodiment of the present invention. The communication terminal 20 includes a data processing device 21 and a storage device 12. The data processing device 21 includes one or more communication application units 111 (111A and 111B), one or more network application units 211 (211X and 211Y), a network transmission / reception unit 212, an integrated transmission control unit 213, and an integrated band estimation unit 115. Have The communication application unit 111, the integrated band estimation unit 115, and the storage device 12 are the same as those in the first embodiment.

  The network application means 211 is an application (non-communication application) that is not intended for communication. The communication application unit 111 and the network application unit 211 perform data transmission / reception via a network transmission / reception unit 212 which is a shared communication unit in the terminal. The communication destination of the network application unit 211 may be the same as the communication terminal of the communication application unit 111 or may be a different communication terminal.

  The network transmission / reception means 212 transmits the data to the communication terminal 20 as a communication partner after giving a transmission time to the transmission data during data transmission during communication execution. Further, when receiving data at the time of communication execution, the network transmission / reception means 212 records and accumulates data communication information related to the received data for the received data from the communication terminal 20 of the communication partner. The integrated band estimation unit 115 acquires data communication information for a predetermined period from the network transmission / reception unit 212. Based on the acquired data communication information, the integrated band estimation unit 115 estimates the available band with the communication terminal 20 of the communication partner.

  When the integrated band estimation unit 115 estimates the usable band, the integrated band estimation unit 115 transmits the estimation result to the integrated transmission control unit 213 of the communication partner communication terminal 20. When the integrated transmission control unit 213 receives the estimation result of the available band, the integrated transmission control unit 213 determines the data transmission method in the network transmission / reception unit 212 using the estimation result of the available band. The integrated transmission control unit 213 instructs the network transmission / reception unit 212 on the determined data transmission method. Upon receiving the instruction, the network transmission / reception unit 212 controls the data transmission of each communication application unit 111 and the data transmission of each network application unit 211 so that the communication quality becomes high according to the instruction. The quality of communication is controlled by the integrated transmission control means 213 instructing the network transmission / reception means 212 on the data transmission method.

  Note that the bandwidth estimation method in the integrated bandwidth estimation means 115 may always be the same estimation method, or an appropriate one is selected from the bandwidth estimation method storage unit 121 according to the type and number of applications being executed and the communication method. However, the estimation method may be changed according to the situation. Also, the transmission control in the integrated transmission control means 213 may always be the same control method, or an appropriate control method from the transmission method storage unit 122 according to the type and number of applications being executed and the usage method of the user. The control method may be changed according to the situation.

  FIG. 6 shows an operation procedure at the time of data transmission. When any one of the communication application means 111 starts communication (step S31), the network transmission / reception means 212 starts giving transmission time to the data to be transmitted (step S32). When the communication is finished (step S33), the network transmission / reception unit 212 finishes giving the transmission time to the transmission data (step S34).

  FIG. 7 shows an operation procedure at the time of data reception. When any one of the communication application means 111 starts communication (step S31), the network transmission / reception means 212 stores therein information (terminal identifier) for identifying the communication terminal 20 of the communication partner (step S41). The network transmission / reception means 212 performs the following processing during communication (step S42). When receiving data (step S11), the network transmission / reception means 212 determines whether or not the data transmission source is the communication terminal 20 having the terminal identifier held in step S41 (step S43). When the data transmission source is the communication partner communication terminal 20, the network transmission / reception means 212 records the data communication information related to the received data from the communication partner communication terminal 20 regardless of the type of application (step S12). When the data transmission source is not the communication terminal 20 of the communication partner, the network transmission / reception unit 212 does not record the information regarding the received data.

  FIG. 8 shows an operation procedure during transmission control. Provision of information related to received data from network transmission / reception means 212 to integrated band estimation means 115, estimation of available bandwidth using information related to received data, and provision of estimated available bandwidth information to communication terminal 20 of the communication partner The operations up to (Steps S21 to 23) are the same as those in the first embodiment shown in FIG.

  The integrated transmission control means 213 of the communication terminal 20 of the communication partner receives the estimated available bandwidth information via the network transmission / reception means 212. The integrated transmission control unit 213 determines a data transmission control method in the network transmission / reception unit 212 based on the received available bandwidth information (step S51). In step S51, the integrated transmission control unit 213 determines not only the data transmission method of the communication application unit 111 but also the data transmission method of the network application unit 211 that communicates with the communication terminal 20 of the communication partner.

  The integrated transmission control means 213 instructs the determined transmission method to the network transmission / reception means 212 (step S52). The network transmission / reception means 212 controls all data transmission to the communication terminal 20 of the communication partner according to the instruction content. For example, “communication application A transmits at 200 kbps” “network application transmits at 1 Mbps in total” can be considered as the instruction content.

  For example, it is assumed that the communication application unit 111A and the communication application unit 111B each receive data twice, and the network application unit 211X receives data from the communication partner communication terminal 20 once during communication execution. In this case, the network transmission / reception means 212 records the data communication information of the data received by the communication application means 111A and 111B and the data communication information of the data received by the network application means 211X, and accumulates a total of five data communication information. To do.

  The network transmission / reception unit 212 provides a total of five data communication information accumulated during a predetermined period to the integrated band estimation unit 115. The integrated band estimation unit 115 combines the received five data communication information and considers the influence of data received from the communication terminal 20 of the communication partner by the network application unit 211X, and then communicates with the communication terminal 20 of the communication partner. Estimate the available bandwidth.

  In the present embodiment, the integrated band estimation unit 115 acquires data communication information from the network transmission / reception unit 212 used in common with the communication application unit 111 and the network application unit 211, and based on the data communication information in a predetermined period, Estimate the available bandwidth. In this embodiment, in addition to the data communication information of the communication application means 111, the available bandwidth is estimated using the data reception information of the network application means 211 that has received data from the communication terminal 20 of the communication partner. For this reason, in addition to the effect obtained in the first embodiment, there is an effect that it is possible to estimate the available bandwidth with high accuracy in consideration of the influence of the network application unit 211.

  By the way, even during communication execution, the communication application means 111 may not receive data within a predetermined period. In that case, the network transmission / reception unit 212 accumulates data reception information related to the reception data of the network application unit 211 that has received the data within a predetermined period, and provides it to the integrated band estimation unit 115. The integrated band estimation unit 115 estimates the available band between the communication terminal 20 and the communication partner 20 based on the data reception information regarding the reception data of the network application unit 211. Therefore, even when there is no data reception by the communication application unit 111, it is possible to perform band estimation using the data reception result of the network application unit 211 and to easily follow the band fluctuation.

  Examples will be described below. This example is an example corresponding to the first embodiment. As the communication terminal 10, a personal computer (PC) is used. The data processing device 11 includes a central processing unit and a memory. A hard disk drive is used as the storage device 12. The function of each means in the data processing device 11 is realized by the central processing unit executing the computer program on the memory. The network transmission / reception means 113 is provided not as an application function but as an OS (operating system) function.

  The communication terminal 10 is connected to a LAN (Local Area Network), and the LANs are connected to each other via a WAN (Wide Area Network). An Internet protocol is used for communication between the communication terminals 10. Communication applications executed on the communication terminal 10 include a VoIP (Voice over Internet Protocol) application (telephone), a shared whiteboard, file transfer, and chat. The user can communicate by using a plurality of these applications at the same time.

  In the following, it is assumed that a user communicates with each other using two communication applications between two PCs. During communication execution, the network transmission / reception unit 113 adds the transmission time to the data of the communication application transmitted to the communication partner PC. The network transmission / reception means 113 adds the transmission time to the option area of the IP header.

  The network transmission / reception means 113 of the PC that has received the data each time an IP packet is received from the communication partner PC (step S11 in FIG. 3), the transmission time and packet length read from the IP header, and the packet reception time Is recorded as data communication information (step S12). The network transmission / reception means 113 continues to receive data and accumulates data communication information for each data reception (packet reception).

The integrated band estimation means 115 acquires the data communication information accumulated for 30 seconds from the network transmission / reception means 113 every 30 seconds (step S21 in FIG. 4). The integrated band estimation means 115 obtains the data flow time from the transmission time and the reception time of the data communication information, and calculates the data throughput per unit time (estimated value of available bandwidth) from the time and the packet length. Obtained (step S22). The integrated band estimation means 115 pays attention to the transmission time and reception time of each record of the acquired data communication information, and calculates the amount of data flowing between the PCs during that time. And the integrated band estimation means 115 about the maximum value in it,
Estimated bandwidth = total of the target packet length ÷ the available bandwidth is estimated by the time when the target packet flows.

  FIG. 9 shows a specific example of data communication information for a predetermined period acquired by the integrated band estimation unit 115. First, the integrated band estimation unit 115 sets one of the data communication information records as a target record, and identifies a packet that has flowed in a time overlapping with the packet of the target record. The integrated band estimation unit 115 identifies a packet of a record in which at least one of the transmission time and the reception time of the packet falls within a time range from the transmission time to the reception time in the record of interest as a packet that has flowed at the overlapping time. . Next, the integrated band estimation unit 115 obtains the sum of the packet lengths of the packets that have been flowing at the specified overlapping time.

  The integrated band estimation unit 115 obtains the sum of the packet lengths of the packets that have flowed at the time overlapping with the packets of the records for all the records of the acquired data communication information for the predetermined period. The integrated band estimation means 115 identifies the record that maximizes the sum of the packet lengths of the data that was flowing during the overlapping time. In FIG. 9, when attention is paid to the record indicated by A, the sum of the packet lengths of the data flowing at the time overlapping with the packet of the record A becomes the maximum. The integrated bandwidth estimation means 115 sets the packet that has flowed through the network at the time overlapping with the packet of the record A shown by ● in FIG. That is, a packet in which at least one of the transmission time and the reception time falls within the time range from the time “2: 32: 32: 440” to the time “2: 32: 33: 432” is set as the calculation target of the available bandwidth estimation. To do.

In FIG. 9, when the sum of the packet lengths of the packets subject to calculation of the available bandwidth estimation is obtained, 65121 + 400 × 17 = 71921 bytes is obtained. On the other hand, among the packets targeted for calculation of the available bandwidth estimation, “2: 32: 32: 437” has the earliest transmission start time. In addition, among the packets targeted for calculation of the available bandwidth estimation, “2: 32: 33: 507” has the latest reception time. Therefore, the time when the packet to be calculated flows is 2: 32: 32: 437-2: 32: 33: 507 = 1160 ms. The integrated band estimation means 115
Estimated bandwidth = 71921 bytes ÷ 1160 ms
= 575368bit ÷ 1160ms
= 496 kbps
Thus, the available bandwidth is estimated to be 496 kbps.

  The integrated band estimation means 115 notifies the estimated value “496 kbps” of the available band to the communication partner PC (step S23). The integrated transmission control unit 114 of the PC that has received the estimated value of the usable bandwidth transmits the data of each communication application to the network transmitting / receiving unit 113 so that the communication quality is improved based on the estimated value of the usable bandwidth. A method is instructed (step S24).

  Specifically, it is assumed that the VoIP application is being executed and the VoIp application is using 32 kbps. The integrated transmission control unit 114 instructs the network transmission / reception unit 113 to transmit the VoIP application packet without restriction because the estimated value of the available bandwidth is larger than 32 kbps. Further, the integrated transmission control unit 114 instructs the network transmission / reception unit 113 to transmit data so that the total used bandwidth of the remaining communication applications is within 496 kbps-32 kbps = 464 kbps. The network transmission / reception means 113 controls data transmission of each communication application according to the instruction (step S25).

  As mentioned above, although this invention was demonstrated based on the suitable embodiment, the communication terminal of this invention, a communication system, the usable bandwidth estimation method, the communication quality control method, and a program are limited only to the said embodiment. The present invention includes various modifications and changes made from the configuration of the above embodiment.

The block diagram which shows the communication terminal of 1st Embodiment of this invention. The block diagram which shows the communication between the communication terminals in communication. The flowchart which shows the operation | movement procedure at the time of data reception. The flowchart which shows the operation | movement procedure in the case of estimation of an available band, and transmission control. The block diagram which shows the terminal device of 2nd Embodiment of this invention. The flowchart which shows the operation | movement procedure at the time of data transmission. The flowchart which shows the operation | movement procedure at the time of the data reception in 2nd Embodiment. The flowchart which shows the operation | movement procedure in the case of estimation of an available band and transmission control in 2nd Embodiment. A table showing data communication information. The block diagram which shows the communication system in patent document 1. FIG.

Explanation of symbols

10, 20: Communication terminal 11, 21: Data processing device 12: Storage device 111: Communication application unit 113, 212: Network transmission / reception unit 114, 213: Integrated transmission control unit 115: Integrated band estimation unit 121: Band estimation method storage unit 122: Transmission method storage unit 211: Network application means

Claims (13)

A communication terminal capable of simultaneously executing a plurality of applications using a network including one or more communication applications, and performing communication with a communication partner by executing the communication application,
A network transmission / reception unit that is commonly used for a plurality of applications that use the network, and that transmits and receives data of the application;
During execution of a plurality of applications using the network, the network transmitting / receiving means acquires data communication information including a data amount and communication time information of data received from a communication partner, and based on the data communication information in a predetermined period. A communication terminal comprising integrated band estimation means for estimating an available band with the communication terminal of the communication partner.   The communication terminal according to claim 1, wherein the integrated band estimation unit estimates the available band by combining data communication information related to data received by each of the plurality of running applications in the predetermined period.   The integrated bandwidth estimation means uses a bandwidth estimation method for estimating the available bandwidth from a bandwidth estimation method storage unit that stores a bandwidth estimation method according to at least one of the type, number, and communication method of the application being executed. The communication terminal according to claim 1, wherein the available bandwidth is estimated according to the selected bandwidth estimation method.   The communication terminal according to any one of claims 1 to 3, further comprising integrated transmission control means for controlling data transmission of an application based on an available band estimated by the integrated band estimation means.   The integrated transmission control means is a control used when controlling the data transmission from a transmission method storage unit that stores a control method according to at least one of the type, number, and usage method of the application being executed. The communication terminal according to claim 4, wherein a method is selected, and data transmission of the application is controlled in accordance with the selected control method.   6. The communication terminal according to claim 1, wherein the network transmission / reception unit records data communication information related to the received data every time the application receives the data.   The communication terminal according to claim 1, wherein the plurality of applications that use the network that is being executed includes one or more communication applications and one or more non-communication applications that are not intended for communication.   The communication terminal according to any one of claims 1 to 7, wherein the plurality of applications that use the network that is being executed includes a plurality of communication applications. A communication system capable of simultaneously executing a plurality of applications using a network including one or more communication applications on a terminal, and performing communication with a communication partner by executing the communication application,
Data amount and communication time of data received from a communication partner by a network transmitting / receiving unit that is commonly used for a plurality of applications using the network and transmits / receives data of the application during execution of the plurality of applications using the network Integrated band estimation means for acquiring data communication information including information, estimating an available band with the communication terminal of the communication partner based on the data communication information in a predetermined period, and transmitting the estimation result; Having a receiving terminal;
A communication system comprising: a transmission terminal having an integrated transmission control unit that receives an estimation result of an available band transmitted by the integrated band estimation unit and controls data transmission of an application based on the estimation result of the available band. A method for estimating a usable bandwidth in a communication terminal capable of simultaneously executing a plurality of applications using a network including one or more communication applications, and performing communication with a communication partner by executing the communication application. ,
The communication terminal is commonly used for a plurality of applications using the network during execution of a plurality of applications using the network, and the network transmission / reception means for transmitting / receiving the data of the application receives data received from a communication partner. Obtaining data communication information including data volume and communication time information;
And a step of estimating an available bandwidth between the communication terminal and the communication terminal of the communication partner based on the data communication information in a predetermined period.   The communication terminal estimates the available bandwidth in the step of estimating the available bandwidth by combining data communication information related to data received by each of the plurality of running applications in the predetermined period. Item 11. The available bandwidth estimation method according to Item 10. A communication quality control method in a communication terminal capable of simultaneously executing a plurality of applications using a network including one or more communication applications, and performing communication with a communication partner by executing the communication application,
The communication terminal is commonly used for a plurality of applications using the network, and the network transmission / reception means communicates during execution of the plurality of applications using the network from a network transmission / reception means for transmitting / receiving the data of the application. Obtaining data communication information including data amount and communication time information of data received from the other party;
The communication terminal, based on the data communication information in a predetermined period, estimating an available bandwidth with the communication partner communication terminal,
A communication quality control method comprising: a step in which the communication terminal controls data transmission of an application based on an estimation result of the available bandwidth. A plurality of applications that use a network can be executed simultaneously, and by executing the communication application, a communication terminal that performs communication with a communication partner performs a process for estimating an available bandwidth, In the communication terminal,
Data commonly used by a plurality of applications using the network and received from a communication partner by the network transmitting / receiving unit during execution of the plurality of applications using the network from a network transmitting / receiving unit that transmits / receives data of the application Processing for acquiring data communication information including the data amount and communication time information of
A program for executing a process of estimating an available bandwidth with the communication terminal of the communication partner based on the data communication information in a predetermined period.

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