JP2016096437A - Communication device, communication method, communication program, and processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently use a plurality of radio links.SOLUTION: A communication device comprises: a first communication unit for performing first communication; a second communication unit for performing second communication; a division capacity determination unit for determining the amount of each piece of division data when content data is divided into multiple pieces of division data and the division data is acquired using first communication and second communication; and a calculation unit for calculating the processing capability of each communication on the basis of time required for obtaining the division data using each of first communication and second communication, and the amount of each piece of division data. The division capacity determination unit determines the amount of the division data acquired using each communication next time on the basis of the processing capability of each of first communication and second communication calculated by the calculation unit.SELECTED DRAWING: Figure 3

Description

  The present invention relates to a communication device, a communication method, a communication program, and a processor.

  When a file is downloaded using wireless communication, a link aggregation technique for dividing and downloading a file by a plurality of wireless links and improving the overall download speed is generally known (for example, Patent Document 1, 2, Non-Patent Documents 1, 2).

Japanese Patent Laid-Open No. 2005-223811 JP 2007-336335 A

“Wireless Japan 2012: Effective speed more than double -KDDI's“ Link Aggregation Wireless Technology ”” [online], May 30, 2012, ITmedia + D Mobile, [Search November 13, 2014], Internet (URL: http://plusd.itmedia.co.jp/mobile/articles/1205/30/news066.html) Takayuki WARABINO et al., Proposal of a device handoff methods for seamless communications, IPSJ SIG Technical Reports, Vol.2003 No. 114 IPSJ SIG Technical Reports, Japan, Japan Information Processing Society of Japan, Information Processing Society of Japan, November 14, 2003, Vol. 2003, pp. 105-112

  For example, when a file is divided and downloaded using an HTTP range request, how to determine how much download size should be assigned to each wireless link is an issue. For example, when the file to be downloaded is equally divided and assigned to each wireless link, when the difference in the throughput of each wireless link is more than double, when downloading with a single (early side) link It will be late. For example, even when a download size is assigned based on the ratio of the physical link speeds of the respective radio links, it is impossible to follow a change in actual throughput that dynamically changes from moment to moment. For this reason, when the throughput decreases in the middle of the process, there may be a case where the entire download speed is faster when the divided download is not performed. Thus, when communicating using a some radio | wireless link, there existed a case where each radio | wireless link could not be used efficiently.

  The present invention has been made in view of the above points, and provides a communication device, a communication method, a communication program, and a processor that can efficiently use a plurality of wireless links.

  SUMMARY An advantage of some aspects of the invention is that a first communication unit that performs first communication, a second communication unit that performs second communication, and the first communication. When the content data is obtained by dividing the content data into a plurality of pieces of divided data using the second communication and the second communication, a divided capacity determining unit that determines a data amount of each of the divided data, the first communication, and the second communication A calculation unit that calculates the processing capacity of each communication based on the time required to acquire the divided data using each of the communication and the data amount of each of the divided data; and The divided capacity determination unit determines a data amount of the divided data to be acquired next using each communication based on the processing capability of each communication of the first communication and the second communication calculated by the calculation unit. The communication device to be determined.

  Further, according to one aspect of the present invention, in the communication device, the divided capacity determination unit determines a data amount of the divided data to be acquired next using each communication of the first communication and the second communication. Based on the communication processing capability calculated by the calculation unit, the data amount is determined such that the time required for acquisition is the same predetermined time.

  According to another aspect of the present invention, in the communication device, the divided capacity determination unit increases the predetermined time each time the divided data is acquired using the first communication and the second communication. To do.

  Further, according to one aspect of the present invention, in the communication device, the divided capacity determination unit may determine the amount of the divided data to be acquired next by using each of the first communication and the second communication. It is determined based on the moving average of the processing capacity of the communication when the divided data is acquired using each communication.

  In addition, according to an aspect of the present invention, in the communication device, the division capacity determination unit may acquire the division using the second communication and then acquire the division data using the first communication. When determining the amount of data, the remaining content data that has not been acquired among the content data is divided into the divided data acquired using the first communication and the divided data acquired using the second communication. The data is divided and the data amount of each of the divided data is determined so that the scheduled acquisition completion times of the divided data are the same.

  In addition, according to an aspect of the present invention, in the communication apparatus, the divided capacity determination unit is the same as an expected completion time of completion of acquisition of the divided data being acquired using the first communication among the remaining content data. A data amount corresponding to completion of acquisition using the second communication at a time is determined as a data amount of the divided data to be acquired next using the second communication, and further, the determination is performed from the remaining content data. The divided data to be acquired next to the divided data being acquired using the first communication and the divided data to be acquired next using the second communication The data is divided into the divided data to be acquired next, and the time required to acquire the data amount of each of the divided data to be divided using the respective communication. Determined so that Flip to.

  In addition, according to an aspect of the present invention, in the communication device, the first communication and the second communication have different logical or physical communication interfaces, and the divided capacity determination unit includes the first communication and the second communication. A data amount of the divided data to be acquired is determined using each of the second communications.

  In addition, according to one aspect of the present invention, when the divided capacity determination unit acquires the content data by dividing the content data into a plurality of pieces of divided data using the first communication and the second communication, Based on a division process for determining the divided data, a time required for the calculation unit to acquire the divided data using each of the first communication and the second communication, and a data amount of each of the divided data Calculating a processing capacity of each communication, and in the dividing process, the divided capacity determination unit is based on the processing capacity of each of the first communication and the second communication. Then, the communication method determines the data amount of the divided data to be acquired next by using each communication.

  According to another aspect of the present invention, a computer determines a data amount of each of the divided data when content data is obtained by dividing the data into a plurality of divided data using the first communication and the second communication. The processing capacity of each communication based on the procedure, the time required to acquire the divided data using each of the first communication and the second communication, and the data amount of each of the divided data And a procedure for determining a data amount of the divided data to be acquired next using each communication based on a processing capacity of each communication of the first communication and the second communication. This is a communication program for execution.

  In addition, according to one aspect of the present invention, when the content data is obtained by dividing the content data into a plurality of pieces of divided data using the first communication and the second communication, the divided capacity determination for determining the data amount of each of the divided data is performed. Processing capacity of each communication based on the time required to acquire the divided data using each of the first communication unit and each of the first communication and the second communication, and the data amount of each of the divided data And the division capacity determination unit obtains the next division using each communication based on the processing capacity of each communication of the first communication and the second communication. A processor that determines the amount of data.

  According to the present invention, a plurality of wireless links can be used efficiently.

It is the schematic which shows the structure of the communication system which concerns on 1st Embodiment of this invention. It is a schematic block diagram which shows the structure of the communication apparatus which concerns on 1st Embodiment. It is a schematic block diagram which shows the structure of the proxy part which concerns on 1st Embodiment. It is explanatory drawing explaining operation | movement of the process of the divided download which concerns on 1st Embodiment. It is explanatory drawing of the example of calculation of the first time throughput which concerns on 1st Embodiment. It is explanatory drawing of the example of calculation of the division size of the division data acquired for the 2nd time concerning 1st Embodiment. It is explanatory drawing of the divided download repeatedly performed by each radio link which concerns on 1st Embodiment. It is explanatory drawing explaining the last part of the division | segmentation download of the content data by 4th Embodiment. It is explanatory drawing explaining the improvement of the last part of the division | segmentation download of the content data by 4th Embodiment.

(First embodiment)
Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a schematic diagram showing the configuration of a communication system according to the first embodiment of the present invention. In this figure, the communication system includes a communication device 1, an access point AP1, a base station device BS1, and server devices Sv101 to Sv104.

  The communication device 1 is a device capable of performing a plurality of different communications such as Wi-Fi (registered trademark, the same applies hereinafter), 3G (3rd Generation: third generation mobile communication system), LTE (Long Term Evolution), and the like. It is. The communication device 1 can bundle a plurality of physical links and handle them as one logical link (link aggregation). The communication device 1 is, for example, a smartphone, a tablet terminal, a feature phone, a personal computer, a mobile router, or the like.

The access point AP1 is a device that accepts a connection request from the communication device 1 and mediates communication to the network. For example, the access point AP1 is a wireless LAN access point, and can perform communication with the communication apparatus 1 by Wi-Fi (referred to as “wireless link L1”. Also referred to as “Wi-Fi communication”).
Base station apparatus BS1 is an apparatus that directly transmits and receives radio waves to and from a mobile phone. The base station device BS1 can perform communication with the communication device 1 using 3G or LTE (referred to as “wireless link L2” or also referred to as “cellular communication”). The base station device BS1 is connected to the mobile phone network N1, and can communicate with devices connected to the network N2 via the mobile phone network N1. For example, the network N2 is the Internet and has a communication protocol different from that of the cellular phone network N1.

The server device Sv101 is, for example, a gateway server, and performs communication protocol conversion between the mobile phone network N1 and the network N2. The server device Sv102 is connected to the network N1, and can communicate with the communication device 1 via the base station device BS1.
The server devices Sv103 and Sv104 are connected to the network N2, and can communicate with the communication device 1 via the access point AP1 or the mobile phone network N1 and the base station device BS1. For example, the server devices Sv102 and Sv103 are domain name system (DNS) server devices (also referred to as DNS servers) and manage domain name information in which host names and domain names on the network are associated with IP addresses. . For example, the server device Sv104 is a content server and performs communication (referred to as HTTP communication) of a protocol such as HTTP (Hypertext Transfer Protocol). The server device Sv104 provides, for example, content data in HTML format to the communication device 1.

  The communication device 1 acquires content data by dividing it into a plurality of times using a plurality of wireless links that are bundled and handled as one wireless link. Here, the content data is a set of data, for example, data of one file downloaded from the server device Sv104. For example, the communication device 1 acquires content data by dividing it into a plurality of pieces using the wireless link L1 and the wireless link L2. In the following description, individual data obtained by dividing content data into a plurality of pieces is also referred to as “divided data”.

  Specifically, the communication device 1 makes an HTTP range request and requests divided data to be acquired using each of the wireless link L1 and the wireless link L2. The range request is a command for requesting only a part of data by specifying a data range in an HTTP header field. For example, in the wireless link L1, the communication device 1 can request and acquire (download) divided data for 125 KB from the top of the content data by specifying “0 KB to 125 KB” of the content data in the range request. . Further, the communication device 1 can request and acquire (download) the divided data for the next 125 KB of the content data by specifying “126 KB to 250 KB” of the content data in the range request in the wireless link L2. . The communication device 1 acquires content data by repeatedly requesting and acquiring divided data using the wireless link L1 and the wireless link L2 until obtaining the last divided data of the content data.

  Further, the communication device 1 determines the data amount (hereinafter also referred to as “data size”) of the divided data to be acquired next using each wireless link based on the throughputs of the wireless link L1 and the wireless link L2. . At this time, if the content data is divided into a large data size from the beginning (for example, if the content data is simply divided into two), the communication device 1 cannot follow the change in the throughput of each wireless link. Request by dividing by fine data size.

  Further, due to the nature of TCP communication, unless the data size to be downloaded is large to some extent, the throughput cannot be improved. Therefore, the communication device 1 does not request by dividing the data by a fixed length and a small data size, but gradually increases the data size to be divided, for example, enlargement of the window size in TCP communication. . The communication device 1 determines the data size of the divided data requested by dividing based on the dynamic throughput at that time.

  For example, the communication device 1 has not measured the throughput of the radio link L1 and the radio link L2 at the start of acquisition of content data. Therefore, the communication apparatus 1 requests divided data having a small data size of about 125 KB each, and based on the time required to acquire each divided data in each wireless link, the throughput (actual throughput) of each wireless link Is calculated. Next, based on the calculated throughput of each wireless link, the communication device 1 determines the data size that can be acquired in the same time α [s: seconds] in each wireless link. Here, the time α [s: seconds] is set so that the data size gradually increases every time content data is acquired (for example, α = 2, 4, 6, 8, 10, 10,...).・).

  As described above, when the communication device 1 obtains content data by using each wireless link, even if a wireless link with a severe fluctuation or a decrease in throughput is included, the communication device 1 finely divides the content data to obtain each wireless data. Since the data size can be appropriately assigned to each wireless link according to the link throughput, the acquisition speed of the entire content data can be increased. Therefore, the communication device 1 can efficiently use a plurality of wireless links.

  In the following description, acquiring content data by dividing it into a plurality of divided data is also simply referred to as “divided download”. In the following description, the data size of the content data is also referred to as “content size”, and the data size of the divided data is also referred to as “divided size”.

<About the communication device 1>
FIG. 2 is a schematic block diagram illustrating a configuration of the communication device 1 according to the present embodiment. The communication device 1 includes an input unit 11, an output unit 12, a control unit 13, a storage unit 14, and a communication unit 15. The control unit 13 includes an application unit 131 and a proxy unit P1. The communication unit 15 includes N interfaces 151-1 to 151-N and a signal strength detection unit 152.

The input unit 11 receives an input from the user of the communication device 1 and outputs information indicating the received input to the control unit 13. The input unit 11 is, for example, a touch panel, buttons, a keyboard, or a camera.
The output unit 12 performs output based on the control of the control unit 13. The output unit 12 is, for example, a display, a speaker, a vibrator, or a light emitting element.

  The control unit 13 controls each unit of the communication device 1 based on information input from the input unit 11 or the communication unit 15 or information stored in the storage unit 14. Of the control unit 13, the application unit 131 reads various programs from the storage unit 14 and executes various programs by executing the read program.

  The proxy unit P1 transmits and receives data via the communication unit 15 based on a request from the application unit 131. For example, the proxy unit P1 receives content data from the server device Sv104 via a plurality of interfaces 151-N (n = 1, 2,..., N) of the communication unit 15 based on a request from the application unit 131. Download separately. Specifically, the proxy unit P1 transmits an HTTP GET request to the server device Sv104 via each of a plurality of interfaces selected from the interfaces 151-1 to 151-N. In addition, the proxy unit P1 includes information (Accept-Ranges: bytes) that permits divided download in the response to the transmitted GET request, and the content size of the content data is equal to or larger than a predetermined threshold (for example, 20 MB or larger). If so, perform a split download. Details of the proxy unit P1 will be described later.

  The communication unit 15 can perform communication of a plurality of communication methods. For example, the interface 151-1 can perform Wi-Fi communication. The interface 151-2 can perform LTE communication (also referred to as “LTE communication”). Further, the interface 151-3 can perform 3G communication (also referred to as “3G communication”). Note that the interface 151-N is not limited to wireless communication, and may perform wired communication. The interface 151-N is not limited to a physical interface, and may be a logical interface.

  The signal strength detection unit 152 detects signal strength information indicating the strength of the signal received by the communication signal (reception signal strength) for each interface 151-N. For example, the signal strength detection unit 152 detects an RSSI (Received Signal Strength Indicator (or Indication)) in communication via the interface 151-1 (Wi-Fi communication) and communication via the interfaces 151-2 and 15-3 ( In LTE communication and 3G communication, a CQI (Channel Quality Indicator) may be detected, and the signal strength detection unit 152 outputs the detected signal strength information to the control unit 13 (for example, the proxy unit P1).

<About proxy part P1>
FIG. 3 is a schematic block diagram illustrating a configuration of the proxy unit P1 according to the present embodiment. The proxy unit P1 includes a session management unit P111, a throughput acquisition unit P112, a split capacity determination unit P113, a signal strength acquisition unit P121, a time measurement unit P122, and an IF selection unit P14.

  The session management unit P111 manages a session. A session is a series of communications, for example, a unit from establishing a connection to disconnecting. For example, a session is generated for each request from an application, and each session ends after a response to each request. For example, a session is generated based on a content data download request from an application, and the content data is downloaded in this session. Specifically, when the session management unit P111 receives a download request for content data from the application unit 131, the session management unit P111 sends an HTTP GET request to the server device Sv104 via the preselected preferentially connected interface 151-N. Send to. In addition, the session management unit P111 includes information (Accept-Ranges: bytes) that permits split download in the response to the transmitted GET request, and the content size of the content data is equal to or greater than a predetermined threshold (for example, 20 MB or more). If there is, start a separate download. For example, when the divided download is started, the session management unit P111 determines the divided size of the divided data to be acquired next for each link based on the throughput (actual throughput) of each link. Then, the session management unit P111 transmits a GET request including a range request for acquiring divided data of the determined division size to the server device Sv104 via each of the interfaces 151-N corresponding to each link.

  The session management unit P111 also includes session identification information (also referred to as “session identification information”), session start time, session end time, request identification information, request application identification information, success / failure of session establishment, Session abnormality reason information indicating the reason for session abnormality, information indicating a wireless link used for the session, and the like are stored in the storage unit 14, and the session is managed by referring to and updating.

  The throughput acquisition unit P112 includes a calculation unit that calculates communication throughput based on the amount of information transmitted and received by the communication unit 15. Throughput is an index representing the processing capacity of communication, and is the data size transmitted within a certain time. Specifically, the throughput acquisition unit P112 performs communication of each wireless link based on the time required to acquire the divided data using each wireless link and the division size of each divided data. Calculate the throughput. The throughput of the present embodiment is the throughput of downlink communication, that is, communication from the access point AP1 or the base station apparatus BS1 to the communication apparatus 1, but the present invention is not limited to this. The throughput acquisition unit P112 outputs the throughput information indicating the calculated throughput in association with the session identification information to the divided capacity determination unit P113.

The divided capacity determining unit P113 determines the divided size of each divided data when content data is divided into a plurality of divided data. For example, the division capacity determination unit P113 first determines the division size of the division data to be acquired using each link because the communication throughput of each link is not measured at the start of the acquisition of the content data. The size is determined (for example, 125 KB). Next, the divided capacity determination unit P113 acquires the throughput of communication when the divided data having the determined division size (for example, 125 KB) is acquired using each of the plurality of links from the throughput acquisition unit P112. Then, the divided capacity determination unit P113 determines the division size of the divided data to be acquired next using each link, based on each acquired throughput.
Further, the divided capacity determining unit P113 outputs the determined divided size in association with the session identification information to the session management unit P111.
The signal strength acquisition unit P121 acquires signal strength information for each interface 151-N from the signal strength detection unit 152, and outputs the acquired signal strength information to the IF selection unit P14.

  The time measurement unit P122 measures time. For example, the time measuring unit P122 measures the time required to acquire the divided data using each link. The timing unit P122 outputs the measured acquisition time to the throughput acquisition unit P112.

  The IF selection unit P14 selects a plurality of interfaces that perform communication from the interfaces 151-1 to 151-N based on information input from each unit of the communication device 1. For example, the IF selection unit P14 uses two wireless links, a wireless link L1 (Wi-Fi communication) and a wireless link L2 (cellular communication), as an example of downloading content data using a plurality of wireless links. In this case, the interface 151-1 and the interface 151-2 are selected. The IF selection unit P14 may select the interface 151-3 as a case where the wireless link L2 (cellular communication) is used.

<About split download processing>
Next, with reference to FIG. 4 to FIG. 7, the divided download process according to the present embodiment will be described. FIG. 4 is an explanatory diagram for explaining the operation of the divided download process according to the present embodiment. FIG. 4 is an example in which two wireless links, a wireless link L1 (Wi-Fi communication) and a wireless link L2 (cellular communication), are selected as wireless links to be divided and downloaded. The divided download process is shown in time series. 5 to 7 are explanatory diagrams supplementing the explanation of the divided download processing according to the present embodiment. It is assumed that the content data DT downloaded by the communication device 1 has a content size of 20 MB.

When the proxy unit P1 receives a download request for the content data DT from the application unit 131, the proxy unit P1 starts communication via the wireless link L1.
The session management unit P111 transmits an HTTP request (GET request) to the server device Sv104 using the wireless link L1, and includes information (Accept-Ranges: bytes) that permits split download within the HTTP response to the transmitted GET request. In addition, when the content size of the content data DT is 20 MB or more, it is determined that the data is the target data of the divided download, and the divided download is executed. Here, since it is assumed that information (Accept-Ranges: bytes) permitting divided download is included and the content size of the content data DT is 20 MB or more, the session management unit P111 starts the divided download. In addition, the session management unit P111 outputs only the header acquired by the HTTP request to the application unit 131.

  First, since the throughput of the radio link L1 and the radio link L2 has not been measured at the start of downloading of the content data DT, the division capacity determination unit P113 acquires each division obtained using the radio link L1 and the radio link L2. All of the data division sizes are determined to be 125 KB and output to the session management unit P111.

The session management unit P111 specifies the 125 KB divided data D (1) from the top of the content data DT in the range request for the wireless link L2, and sends an HTTP request to the server device using the wireless link L2. It transmits to Sv104 (step S110).
Similarly, the session management unit P111 specifies the divided data D (2) for 125 KB next to the divided data D (1) in the content data DT from the content data DT by using a range request, and divides the wireless link L1. An HTTP request for requesting data acquisition is transmitted to the server device Sv104 using the wireless link L1 (step S120).

  In step S110 and step S120, an HTTP request is transmitted to each of the radio link L2 and the radio link L1, so that the radio link L2 and the radio link L1 are respectively parallel to the divided data D (1). Each download with data D (2) is started (step S111, step S121).

  Here, the download of the divided data by the wireless link L1 is completed before the wireless link L2. That is, it can be seen that the wireless link L1 has a higher throughput than the wireless link L2. When the download of the divided data D (2) is completed on the wireless link L1 (step S122), the session management unit P111 stores the downloaded divided data D (2) in the buffer 1 in the buffer 140 (step S123). On the other hand, when the download of the divided data D (1) is completed on the wireless link L2 (step S112), the session management unit P111 stores the downloaded divided data D (1) in the buffer 2 in the buffer 140 (step S113). . Here, the buffer 140 is a buffer area in the storage unit 14. The session management unit P111 sequentially outputs the data stored in the buffer 140 to the application unit 131.

  Further, the throughput acquisition unit P112 calculates the throughput at the time of downloading the first divided data of the wireless link L1 based on the time and the divided size required for downloading the divided data D (2) on the wireless link L1. Similarly, the throughput acquisition unit P112 calculates the throughput at the time of downloading the first divided data of the wireless link L2 based on the time and the divided size required for downloading the divided data D (1) on the wireless link L2.

FIG. 5 is an explanatory diagram of an example of calculating the initial throughput. Assuming that the time required for downloading the 125 KB divided data D (2) on the wireless link L1 is TW (1) [s: seconds], the initial throughput TPW (1) [bps] of the wireless link L1 is expressed by the following equation: It is represented by
TPW (1) = 125KB × 8 ÷ TW (1)

Further, assuming that the time required for downloading the 125 KB divided data D (1) in the wireless link L2 is TC (1) [s: seconds], the initial throughput TPC (1) [bps] of the wireless link L2 is as follows: It is expressed by the following formula.
TPC (1) = 125KB × 8 ÷ TC (1)

  Next, the division capacity determination unit P113, based on the initial throughputs of the radio link L1 and the radio link L2, respectively, the division size of the division data acquired next (second time) of the radio link L1 and the radio link L2. To decide. For example, the division capacity determination unit P113 calculates the division size that can be acquired at the same time α [s: seconds] in each of the radio link L1 and the radio link L2, and the division size of the division data that is acquired next (second time). Determine as. Here, the time α is, for example, α = 2, 4, 6, 8, 10 according to the number of times of acquisition of the divided data (Kth, K = 2, 3, 4, 5, 6, 7,...). , 10,... (In this case, the upper limit is set to 10 seconds). Note that the value of the time α and the upper limit value for each number of acquisitions can be arbitrarily set.

FIG. 6 is an explanatory diagram of a calculation example of the division size of the divided data acquired for the second time.
As the divided size of the divided data D (3) acquired second time by the wireless link L1, the divided size SIZEW (which can be acquired at the time α [s: second] by the initial throughput TPW (1) [bps] of the wireless link L1 ( 2) [byte] is expressed by the following equation.
SIZEW (2) = TPW (1) × α ÷ 8
Here, α = 2 because it is the division size of the divided data acquired for the second time.
Note that TW (2) [s: seconds] is the time required for downloading the divided data D (3), and if it can be actually downloaded with the calculated throughput TPW (1) [bps], the time α [s: seconds]. It becomes.

Further, as the division size of the divided data D (4) acquired second time by the wireless link L2, the divided size that can be acquired at the time α [s: second] by the initial throughput TPC (1) [bps] of the wireless link L2. SIZEC (2) [bytes] is expressed by the following equation.
SIZEC (2) = TPC (1) × α ÷ 8
Here, α = 2 because it is the division size of the divided data acquired for the second time.
Note that TC (2) [s: seconds] is the time required to download the divided data D (4), and if it can be actually downloaded with the calculated throughput TPC (1) [bps], the time α [s: seconds]. It becomes.

  Returning to FIG. 4, the second divided data download process will be described. The divided capacity determination unit P113 calculates the division size of the divided data acquired the second time from the wireless link on which the first download of the divided data has been completed first, and outputs it to the session management unit P111. Then, the session management unit P111 starts the second download of the divided data from the wireless link on which the download of the first divided data is completed first.

  Specifically, first, the division capacity determination unit P113 obtains the division size SIZE (2) that can be acquired in 2 seconds by the initial throughput TPW (1) [bps] for the wireless link L1 for which the first download has been completed first. [byte] is calculated and output to the session management unit P111 as the divided size of the divided data D (3) acquired for the second time. The session management unit P111 designates divided data D (3) for SIZEW (2) [byte] next to the divided data D (2) in the content data DT in the range request for the wireless link L1. Then, an HTTP request for requesting acquisition of the divided data D (3) is transmitted to the server device Sv104 using the wireless link L1 (step S130). In response to this request, download of the divided data D (3) is started on the wireless link L1 (step S131). When the download of the divided data D (3) is completed on the wireless link L1 (step S132), the session management unit P111 stores the downloaded divided data D (3) in the buffer 3 in the buffer 140 (step S133). .

  On the other hand, for the wireless link L2, when the initial download is completed, the division capacity determination unit P113 sets the division size SIZEC (2) [bytes] that can be acquired in 2 seconds by the initial throughput TPC (1)) [bps]. Calculate and output to the session management unit P111 as the divided size of the divided data D (4) acquired second time. The session management unit P111 designates the divided data D (4) for SIZEC (2) [bytes] next to the divided data D (3) in the content data DT with respect to the wireless link L2 by the range request. Then, an HTTP request for requesting acquisition of the divided data D (4) is transmitted to the server device Sv104 using the wireless link L2 (step S140). In response to this request, download of the divided data D (4) is started on the wireless link L2 (step S141). When the download of the divided data D (4) is completed on the wireless link L2 (step S142), the session management unit P111 stores the downloaded divided data D (4) in the buffer 4 in the buffer 140 (step S143). .

  Here, since the wireless link L1 has a higher throughput at the time of the first download than the wireless link L2, the divided size SIZE (2) of the divided data D (3) is SIZEC (2) of the divided data D (4). ) Is a larger data size.

  Then, until the download of the content data DT is completed, the division size of the next division data is determined based on the throughput at the time of the previous division data download in each of the radio link L1 and the radio link L2. The download is repeated. For example, the third division size can be obtained in 4 seconds with the second throughput, the fourth division size can be obtained in 6 seconds with the third throughput, and the fifth division size is the fourth. The division size is gradually increased, such as a division size that can be acquired in 8 seconds depending on the throughput of the first, and the division size that can be acquired in 10 seconds based on the previous throughput is set for the sixth and subsequent times.

FIG. 7 is an explanatory diagram of divided download repeatedly performed on each wireless link. In the wireless link L1, the divided data D (2) having the divided size 125KB is downloaded for the first time, and the divided data D (3) having the divided size SIZE (2) [byte] is downloaded for the second time. Then, in the Xth time (X is a natural number), the divided data D (M) having a division size SIZE (X) [byte] is downloaded (M is a natural number). Here, the division size SIZE (X) [bytes] is a data size that can be acquired in α seconds by the “X−1” -th throughput TPW (X−1) [bps], and can be expressed by the following equation. it can.
SIZEW (X) = TPW (X−1) × α ÷ 8

The X-th throughput TPW (X) [bps] can be expressed by the following equation, where TW (X) [s: seconds] is the time required for downloading the divided data D (M).
TPW (X) = SIZE (X) × 8 ÷ TW (X)

On the other hand, in the radio link L2, the divided data D (1) having the divided size 125KB is downloaded for the first time, and the divided data D (4) having the divided size SIZEC (2) [byte] is downloaded for the second time. Then, at the Y-th time (Y is a natural number), the divided data D (M−1) having the divided size SIZEC (Y) [byte] is downloaded. Here, the division size SIZEC (Y) [bytes] is a data size that can be acquired in α seconds by the “Y−1” -th throughput TPC (Y−1) [bps], and can be expressed by the following equation. it can.
SIZEC (Y) = TPC (Y−1) × α ÷ 8

The Y-th throughput TPC (Y) [bps] can be expressed by the following equation, where TC (Y) [s: second] is the time required to download the divided data D (M−1). .
TPC (Y) = SIZEC (Y) × 8 ÷ TC (Y)

  As described above, when the content data download request is received from the application unit 131, the proxy unit P1 downloads the content data in a divided manner. The pieces of divided data that are divided and downloaded by the proxy unit P1 are combined and output to the application unit 131.

As described above, according to the present embodiment, in the communication apparatus 1, the interface 151-1 (an example of the first communication unit) performs Wi-Fi communication (an example of the first communication). The interface 151-2 (an example of the second communication unit) performs cellular communication (an example of the second communication). The proxy unit P1 determines a division size (data amount) of each divided data when content data is divided into a plurality of data and acquired using the first communication and the second communication. In addition, the proxy unit P1 determines the throughput of each communication (based on the time required to acquire the divided data using each of the first communication and the second communication and the division size of each divided data). Processing capacity). And the proxy part P1 determines the division size of the division data acquired next using each communication based on the throughput of each communication of 1st communication and 2nd communication.
Thereby, the communication apparatus 1 can utilize a some radio | wireless link efficiently. For example, the communication device 1 divides content data finely and assigns a data size appropriately to each wireless link according to the throughput of each wireless link, even if the wireless link includes a fluctuation or drastic decrease in throughput. Since it can be acquired, the download speed of the entire content data can be increased.

Further, according to the present embodiment, the proxy unit P1 uses the respective communications of the first communication and the second communication to determine the division size of the divided data to be acquired next based on the calculated throughput of each communication. The division size is determined such that the time required for acquisition is the same predetermined time (for example, α seconds) using each communication.
As a result, when the communication device 1 obtains content data by dividing each wireless link, the wireless link with a high throughput can compensate for the wireless link with a low throughput. For this reason, the communication device 1 can suppress an increase in download time due to a high-throughput wireless link being pulled by a low-throughput wireless link. Further, the communication device 1 can contribute to improving the speed of the download time for a wireless link having a low throughput regardless of the amount that can be acquired in a predetermined time (for example, α seconds). That is, the communication device 1 can download the content data so as to be supplemented by a plurality of wireless links, and can increase the download speed of the entire content data.

  Further, according to the specification of the window size of TCP communication, if the bandwidth is sufficient, downloading data with a large data size widens the window size, leading to an improvement in throughput. Therefore, according to the present embodiment, the proxy unit P1 lengthens the predetermined time each time the divided data is acquired using the first communication and the second communication (for example, α = 2, 4, 6). , 8, 10, 10,... As a result, the communication device 1 can increase the download speed of the entire content data.

  Further, according to the present embodiment, the first communication and the second communication are different in logical or physical communication interface. The proxy unit P1 determines the division size of the divided data acquired using each of the first communication and the second communication.

(Second Embodiment)
When the proxy unit P1 determines the division size of the divided data to be acquired next using each radio link, the proxy unit P1 is not based only on the throughput immediately before each radio link, but is the moving average of the previous throughput of each radio link. You may decide based on. Thereby, the communication apparatus 1 can prevent the division size from being determined more than necessary when there is an instantaneous change in throughput.

Specifically, the division capacity determination unit P113 uses the radio link L1 and the radio link L2 to obtain the division size of the division data to be acquired next, and previously obtains the division data using each communication. It is determined based on the moving average of the communication throughput.
For example, in the divided download repeatedly performed on each wireless link shown in FIG. 7, the X-th divided size SIZEW (X) [byte] of the wireless link L1 can be expressed by the following equation.
SIZEW (X) = TPWave × α ÷ 8
Here, TPWave [bps] is a moving average of the throughput of the radio link L1 from the first time to the (X-1) th time.

The Y-th division size SIZEC (Y) [byte] of the radio link L2 can be expressed by the following equation.
SIZEC (Y) = TPCave × α ÷ 8
Here, TPCave [bps] is a moving average of the throughput of the radio link L2 from the first time to the (Y-1) th time.

  Note that the moving average of throughput may be a simple moving average without weighting each throughput, or may be a weighted moving average with weighting added. Further, the moving average of throughput may be a moving average of throughput of the latest several times (for example, three times).

(Third embodiment)
In the first embodiment, the time α is gradually increased according to the number of times of division data acquisition so that the division size of the division data to be acquired next gradually increases (for example, α = 2, 4, 6). , 8, 10, 10,...)) An example has been described, but the present invention is not limited to this. For example, the communication device 1 may set the time α as a fixed value when determining the division size of the second and subsequent divided data.

(Fourth embodiment)
The throughput of each wireless link is not always constant and changes from moment to moment. For this reason, for example, when split download is performed with two wireless links, if the throughput of one wireless link is reduced in the middle, it may take more time to download than expected. For example, split downloads that should have been completed simultaneously on two wireless links may not be completed at the same time, and the completion of the entire download may be pulled until the download of the wireless link whose throughput has been reduced is completed .

FIG. 8 is an explanatory diagram for explaining the last part of the divided download of content data.
With reference to this figure, an example will be described in which there is a difference between the scheduled acquisition times of the divided data allocated to the radio link L1 and the radio link L2. The horizontal axis indicates time T, and the last part of the divided data of the radio link L1 and the radio link L2 is shown in time series. The divided data D (M) is the last divided data in the content data DT, and is the last divided data downloaded by the wireless link L2. Further, the divided data D (M−1) is the second divided data from the end of the content data DT and is the last divided data to be downloaded through the radio link L1. The divided data D (M-2) is the third divided data from the end of the content data DT, and is the second divided data from the last downloaded by the radio link L2.

  At time T10, the download of the divided data D (M-2) is completed on the radio link L2. Then, the throughput is calculated from the time TC (Y-1) [s: seconds] required to acquire the divided data D (M-2), and the time α (for example, the moving average of the calculated throughput or the previous throughput is calculated. , Α = 10) The data size that can be acquired in [s: seconds] is determined as the division size SIZEC (Y) [bytes] of the division data D (M) to be downloaded next. Here, since the divided data D (M) is the last data of the content data DT, the divided size SIZEC (Y) [bytes] of the divided data D (M) is a time α (for example, α = 10) [ The data size is less than or equal to the data size that can be acquired in [s: seconds].

  On the other hand, in the wireless link L1, at time T10, the divided data D (M−1) that is the second divided data from the end of the content data DT is being downloaded. The scheduled completion time for downloading the divided data D (M-1) is a time T20 determined by the time TW (X) [s: seconds] required for downloading the divided data D (M-1). Therefore, if the divided download is continued as it is, the download of the divided data D (M−1) using the radio link L1 is completed at time T20, and thereafter, the radio link L2 is performed between time T20 and time T30. Only the download of the divided data D (M) using is continued until time T30 when the download is completed. That is, a period from time T20 to time T30 in which the download is performed with only one of the radio links occurs, leading to a decrease in download speed.

Therefore, in the present embodiment, when there is a difference in the scheduled download completion time of the divided data assigned to each wireless link, the download of one wireless link is completed first, and the download of the other wireless link is completed. Improve that you don't play for a long time. Specifically, it is improved at the part where the last divided data of the content data is downloaded.
For example, when the communication device 1 divides and acquires content data using the wireless link L1 and the wireless link L2, the divided data acquired next on one of the wireless links is the end of the content data (the end of the file). Is reached, the availability of the other radio link is confirmed, and the division size of each piece of divided data acquired using each wireless link is adjusted so that both wireless links finish obtaining divided data at the same time.

  FIG. 9 is an explanatory diagram for explaining the improvement of the last part of the divided download of content data. This figure shows an example of the improvement of the last part of the divided download shown in FIG. 8, and the horizontal axis shows the time T as in FIG.

  At time T10, the divided capacity determination unit P113 uses the wireless link L2 to calculate the throughput calculated by the time TC (Y-1) [s: seconds] required to acquire the divided data D (M-2) or until then. The divided size SIZEC (Y) [bytes] of the divided data D (M) that can be acquired at the time α (for example, α = 10) [s: seconds] is calculated by the moving average of the throughputs. Here, description will be made assuming that a moving average of throughput is used. When the divided data D (M) includes the last data of the content data (when the data is data up to the file end), the divided data D (M) is finally downloaded by the radio link L1 and the radio link L2. It is further divided and assigned to each radio link so that the scheduled completion times are the same. As described above, the division size SIZEC (Y) [byte] of the division data D (M) is equal to or smaller than the data size that can be acquired at time α (for example, α = 10) [s: seconds].

Specifically, the divided capacity determination unit P113 divides the divided data D (M) into divided data D (M1), divided data D (M2), and divided data D (M3).
The divided data D (M1) is divided into the parts that are downloaded using the wireless link L2 at the same time as the download completion scheduled time T20 of the divided data D (M-1) being acquired using the wireless link L1. It is data.
The division size SIZEC (Y1) [bytes] of the division data D (M1) is a time from time T10 to time T20 is time TL10 [s: seconds], and a moving average of the throughput of the radio link L2 is TPCave [bps]. Then, it can be expressed by the following formula.
SIZEC (Y1) = TPCave × TL10 ÷ 8

The divided data D (M2) and the divided data D (M3) are data obtained by further dividing the remaining data obtained by removing the divided data D (M1) from the divided data D (M) into two. The divided data D (M2) and the divided data D (M3) are divided so that the time required for downloading by the wireless link L1 and the wireless link L2 is the same. In the example shown in this figure, at time TL20 [s: seconds] from time T20 to time T25, the divided data D (M2) is downloaded using the wireless link L2, and the divided data D (M3) is transmitted through the wireless link L1. It is divided so that it can be downloaded.
Here, assuming that the moving average of the throughput of the radio link L1 is TPWave [bps] and the moving average of the throughput of the radio link L2 is TPCave [bps], the time TL20 [s: second] can be expressed by the following equation. .
Time TL20 = (SIZEC (Y) −SIZEC (Y1)) × 8 ÷ (TPCave + TPWave)

In this case, the division size SIZEC (Y2) [bytes] of the division data D (M2) can be expressed by the following equation, where the moving average of the throughput of the radio link L2 is TPCave [bps].
SIZEC (Y2) = TPCave × TL20 ÷ 8

Further, since the division size SIZEC (Y3) [byte] of the division data D (M3) is downloaded using the radio link L1, if the moving average of the throughput of the radio link L1 is TPWave [bps], It can be expressed by a formula.
SIZEC (Y3) = TPWave × TL20 ÷ 8

  Then, at time T10, the session management unit P111 designates the divided data D (M1) with a range request and transmits an HTTP request to the server device Sv104 using the wireless link L2. Further, when the download of the divided data D (M1) is completed on the wireless link L2 (for example, time T20), the session management unit P111 designates the divided data D (M2) with a range request, and sends an HTTP request to the wireless link. It transmits to server apparatus Sv104 using L2. Further, when the download of the divided data D (M−1) is completed on the wireless link L1 (for example, time T20), the session management unit P111 designates the divided data D (M3) with a range request, and sends an HTTP request. It transmits to server apparatus Sv104 using the wireless link L1. Thereby, the scheduled completion time of the entire download can be advanced from time T30 to time T25, and the download speed of the entire content data can be increased.

  As described above, in the present embodiment, the proxy unit P1 acquires next using cellular communication (an example of second communication) while acquiring divided data using Wi-Fi communication (an example of first communication). When determining the division size of the divided data to be acquired, the last divided data (that is, the remaining unacquired content data) of the content data is acquired using the divided data acquired using the first communication and the second communication. The data is divided into divided data. In addition, the proxy unit P1 determines the division size of each piece of divided data so that the scheduled completion time (scheduled completion time of download) of each piece of divided data is the same.

  That is, the communication device 1 assigns the divided data to each wireless link so that the final completion time of downloading of each wireless link becomes the same at the last part of the divided download of the content data. As a result, the communication device 1 suppresses the occurrence of a period during which one wireless link completes downloading first and the other wireless link completes downloading (does not contribute to downloading). Can do. Therefore, the communication device 1 can maximize the utilization efficiency of the radio link, and can maximize the acquisition speed of the entire content data.

  For example, in the present embodiment, the proxy unit P1 includes the divided data (for example, the divided data D (M) that is being acquired using the first communication among the last divided data (for example, the divided data D (M)) described above. -1)), the divided size for which the acquisition is completed using the second communication at the same time as the scheduled download completion time is divided data (for example, divided data D (M1) to be acquired next using the second communication). )) Is determined as the division size. Further, the proxy unit P1 obtains the content data obtained by removing the determined divided size divided data (for example, divided data D (M1)) from the last divided data (for example, divided data D (M)). The divided data acquired after the divided data being acquired using one communication (for example, divided data D (M2)) and the divided data acquired next to the divided data acquired next using the second communication ( For example, the data is divided into divided data D (M3)). Here, the proxy unit P1 takes the same time to acquire the divided sizes of the respective divided data to be divided (for example, the divided data D (M2) and the divided data D (M3)) using the respective communications. To be determined.

  In the present embodiment, the proxy unit P1 divides the last part of the content data divided download (for example, divided data D (M)) into three pieces of divided data, and completes the final download of each radio link. Although an example in which the scheduled time (acquired completion time of acquisition) is assigned to each radio link so as to be the same has been described, it is not limited thereto. For example, the proxy unit P1 may divide the last part of the content data divided download (for example, divided data D (M)) into two pieces of divided data. In this case, the proxy unit P1 corresponds to the divided data (divided data D (M1) + divided data D (M2) that can be acquired in the time from time T10 to time T25 (time TL10 + time TL20) using the radio link L2. ) And divided data (corresponding to divided data D (M3)) that can be acquired in the time from time T20 to time T25 (time TL20) using the wireless link L1.

Note that a part of the communication device 1 in the above-described embodiment may be realized by a computer. In that case, the program for realizing the control function may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read by the computer system and executed. Here, the “computer system” is a computer system built in the communication apparatus 1 and includes an OS and hardware such as peripheral devices. The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” is a medium that dynamically holds a program for a short time, such as a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, In this case, a volatile memory inside a computer system that serves as a server or a client may be included that holds a program for a certain period of time. The program may be a program for realizing a part of the functions described above, and may be a program capable of realizing the functions described above in combination with a program already recorded in a computer system.
Moreover, you may implement | achieve part or all of the communication apparatus 1 in embodiment mentioned above as integrated circuits, such as LSI (Large Scale Integration). Each functional block of the communication device 1 may be individually made into a processor, or a part or all of them may be integrated into a processor. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. In addition, when an integrated circuit technology that replaces LSI appears due to the advancement of semiconductor technology, an integrated circuit based on the technology may be used.

  As described above, the embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to the above, and various design changes and the like can be made without departing from the scope of the present invention. It is possible to

  DESCRIPTION OF SYMBOLS 1 ... Communication apparatus, AP1 ... Access point, BS1 ... Base station apparatus, Sv101, Sv102, Sv103, Sv104 ... Server apparatus, 11 ... Input part, 12 ... Output part, 13 ... Control part, 14 ... Storage part, 15 ... Communication part, 131 ... Application part, P1 ... Proxy part, 151-1 to 151-N ... Interface, 152 ... Signal strength detection unit, P111 ... session management unit, P112 ... throughput acquisition unit, P113 ... split capacity determination unit, P121 ... signal strength acquisition unit, P122 ... timing unit, P14 ... IF selector

Claims (10)

A first communication unit for performing first communication;
A second communication unit for performing second communication;
A divided capacity determining unit that determines a data amount of each of the divided data when content data is divided into a plurality of divided data and acquired using the first communication and the second communication;
The processing capacity of each communication is calculated based on the time required to acquire the divided data using each of the first communication and the second communication and the data amount of each of the divided data. A calculation unit;
With
The divided capacity determination unit
Based on the processing capacity of each of the first communication and the second communication calculated by the calculation unit, determine the data amount of the divided data to be acquired next using each communication;
Communication device. The divided capacity determination unit
The time required to acquire the data amount of the divided data to be acquired next using the communication of the first communication and the second communication based on the processing capacity of the communication calculated by the calculation unit, respectively. Is determined so that the data amount is the same predetermined time,
The communication apparatus according to claim 1. The divided capacity determination unit
Each time the divided data is acquired using the first communication and the second communication, the predetermined time is lengthened.
The communication apparatus according to claim 2. The divided capacity determination unit
The data amount of the divided data acquired next using each of the first communication and the second communication is the moving average of the processing capacity of the communication when the divided data was previously acquired using the respective communication. To make a decision based on the
The communication apparatus as described in any one of Claim 1 to 3. The divided capacity determination unit
When determining the data amount of the divided data to be acquired next using the second communication while acquiring the divided data using the first communication, the remaining content data not acquired among the content data is determined. , Dividing the divided data acquired using the first communication and the divided data acquired using the second communication, so that the scheduled acquisition completion times of the divided data are the same. Determining a data amount of the divided data;
The communication apparatus as described in any one of Claim 1 to 4. The divided capacity determination unit
Of the remaining content data, the amount of data for the completion of acquisition using the second communication at the same time as the scheduled acquisition completion time of the divided data being acquired using the first communication is set to the second content data. Determine the data amount of the divided data to be acquired next using communication,
Further, the divided data to be acquired next to the divided data being acquired using the first communication, the divided data obtained by removing the divided data of the determined data amount from the remaining content data, and the second The time required to acquire the data amount of each of the divided data to be divided into the divided data to be acquired next to the divided data to be acquired next using communication and the data amount of the divided data to be divided. Decide to be the same,
The communication device according to claim 5. The first communication and the second communication have different logical or physical communication interfaces,
The divided capacity determination unit
Determining the data amount of the divided data to be acquired using each of the first communication and the second communication;
The communication apparatus according to any one of claims 1 to 6. A division process for determining a data amount of each of the divided data when the divided capacity determining unit divides and acquires the content data into a plurality of divided data using the first communication and the second communication;
Based on the time required for the calculation unit to acquire the divided data using each of the first communication and the second communication and the data amount of each of the divided data, each communication process A calculation process to calculate the ability;
Have
In the division process, the divided capacity determination unit determines a data amount of the divided data to be acquired next using each communication based on a processing capacity of each communication of the first communication and the second communication. decide,
Communication method. On the computer,
A procedure for determining a data amount of each of the divided data when content data is divided into a plurality of divided data and acquired using the first communication and the second communication;
The processing capacity of each communication is calculated based on the time required to acquire the divided data using each of the first communication and the second communication and the data amount of each of the divided data. Procedure and
A procedure for determining a data amount of the divided data to be acquired next using each communication based on a processing capacity of each communication of the first communication and the second communication;
Communication program for executing A divided capacity determining unit that determines the data amount of each of the divided data when content data is divided into a plurality of divided data and acquired using the first communication and the second communication;
The processing capacity of each communication is calculated based on the time required to acquire the divided data using each of the first communication and the second communication and the data amount of each of the divided data. A calculation unit;
With
The divided capacity determination unit
Based on the processing capacity of each communication of the first communication and the second communication, determine the data amount of the divided data to be acquired next using each communication,
Processor.

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