Communication device, communication method, and communication program

Abstract

A communication device (100) can perform, by using a single or a plurality of communication lines, communication with a partner device connected to a transmission destination device, in order to transmit, to the transmission destination device, packets including data received from a transmission source device. The communication device includes: a reception unit (101) that receives packets from the transmission source device; a required characteristic determination unit (103) that determines a required characteristic required for communication, on the basis of transmission source device information indicating the transmission source device identified from the packets and transmission destination device information indicating the transmission destination device identified from the packets; a plan determination unit (105) that determines, on the basis of the required characteristic, a plan that is for a single communication line or a combination of a plurality of communication lines to be used for communication; a transmission control unit (106) that distributes the packets to the respective communication lines on the basis of the plan; and a plurality of transmission units (107) that are connected to the respective communication lines and that transmit the packets.

Description

Communication device, communication method, and communication program CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application is based on Japanese Patent Application No. 2024-105268, filed on June 28, 2024, the contents of which are incorporated herein by reference.

[0002] The present application relates to a communication device or the like that transmits data using one or more communication lines, and relates to a communication device or the like that transmits application data to a server using one or more communication lines from a communication device mounted on a mobile object such as an automobile.

[0003] When transmitting data from a communication device, if a multi-link communication device that simultaneously uses multiple lines is used, the data transmission time can be shortened.

[0004] With the aim of improving this speed, for example, Patent Document 1 describes a multi-link communication device that allocates communications according to the effective transmission speed of each line, thereby realizing efficient multi-link communication with low latency overall without causing excessive delays or placing excessive loads on each line.

[0005] Japanese Patent Application Laid-Open No. 2000-216815

[0006] Here, the inventors have found the following problem as a result of detailed investigation. According to Patent Document 1, since the characteristics of the communication path other than the effective transmission speed of each line are not taken into consideration, it is not possible to deal with cases where other characteristics take priority over the priority of the data transmission time. For example, when transmitting data that is sensitive to packet loss, it is more desirable to use a line with a low packet loss rate than a line with a high communication speed.

[0007] The present disclosure aims to realize a method for allocating packets to communication lines suitable for transmission, taking into consideration required characteristics, which are communication characteristics required by the packets to be transmitted.

[0008] A communication device according to one aspect of the present disclosure is a communication device capable of communicating with a counterpart device connected to a destination device using one or more communication lines in order to transmit packets containing data received from the source device to the destination device, and comprises: a receiving unit that receives the packets from the source device; a required characteristics determination unit that determines the required characteristics required for the communication based on source device information indicating the source device identified from the packet and destination device information indicating the destination device identified from the packet; a strategy determination unit that determines a strategy, which is a combination of one or more of the communication lines to be used for the communication, based on the required characteristics; a transmission control unit that distributes the packets to each communication line based on the strategy; and a plurality of transmission units connected to each communication line and that transmit the packets.

[0009] It should be noted that the numbers in parentheses in the claims indicate the correspondence between the present invention and the embodiments described below, and are not intended to limit the present invention.

[0010] With the above-described configuration, the communication device etc. disclosed herein determines the required characteristics for communication based on source device information and destination device information, and allocates packets to each line based on these required characteristics, thereby enabling multi-link communication suitable for the type of packet, the type of data contained in the packet, etc.

[0011] The above and other objects, features, and advantages of the present disclosure will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which Fig. 1 is an explanatory diagram illustrating an overall configuration including a communication device 100 according to each embodiment, Fig. 2 is an explanatory diagram illustrating the layout of the communication device 100 according to each embodiment, Fig. 3 is a block diagram illustrating an example configuration of the communication device 100 according to a first embodiment, Fig. 4 is an explanatory diagram illustrating a method of determining required characteristic information according to the first embodiment and its contents, Fig. 5 is an explanatory diagram illustrating an example of required characteristic information according to the first embodiment, Fig. 6 is an explanatory diagram illustrating an example of policy characteristic information according to the first embodiment, Fig. 7 is an explanatory diagram illustrating vector calculations by the policy decision unit according to the first embodiment, and Fig. 8 is an explanatory diagram illustrating a method of determining required characteristic information according to the first embodiment. FIG. 11 is a flow diagram illustrating a method for determining a strategy for the communication device 100 of embodiment 1; FIG. 12 is an explanatory diagram illustrating an example of required characteristic information for variant 1 of embodiment 1; FIG. 13 is an explanatory diagram illustrating vector calculations of the strategy determination unit of variant 1 of embodiment 1; and FIG. 14 is an explanatory diagram illustrating vector calculations of the strategy determination unit of variant 2 of embodiment 1.

[0012] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0013] The present invention described below refers to the invention described in the claims and is not limited to the following embodiments. Furthermore, at least the words in double quotation marks refer to the words described in the claims and are not limited to the following embodiments.

[0014] The configurations and methods recited in the dependent claims are optional configurations and methods in the inventions recited in the independent claims. The configurations and methods of the embodiments corresponding to the configurations and methods recited in the dependent claims, as well as the configurations and methods recited only in the embodiments without being recited in the claims, are optional configurations and methods in the present invention. The configurations and methods recited in the embodiments when the recitation of the claims is broader than the recitation of the embodiments are also optional configurations and methods in the present invention, in the sense that they are examples of the configurations and methods of the present invention. In either case, by being recited in the independent claims, they become essential configurations and methods of the present invention.

[0015] The effects described in the embodiments are effects obtained when the configurations of the embodiments are provided as examples of the present invention, and are not necessarily effects that the present invention has.

[0016] When there are multiple embodiments (including examples and modifications, the same applies in this paragraph), the configurations disclosed in each embodiment are not limited to each embodiment, but can be combined across the embodiments. For example, a configuration disclosed in one embodiment may be combined with another embodiment. Also, configurations disclosed in multiple embodiments may be collected and combined.

[0017] The problems described in this disclosure are not publicly known problems, but have been independently discovered by the inventors, and together with the configuration and method of this disclosure, these facts affirm the inventive step of the invention.

[0018] 1. Configuration Prerequisite for the Embodiments (Overall Configuration and Arrangement of Communication Devices) The arrangement of the communication device 100 of each embodiment will be described using FIGS. 1 and 2. First, an example of the overall configuration including the communication device 100 of each embodiment will be described using FIG. 1. This example illustrates a case where data is transmitted from a first terminal device 10(N) (N: an integer assigned to each first terminal device) to a second terminal device 20(M) (M: an integer assigned to each second destination device). The first terminal device 10(N) (corresponding to the "source device") divides data generated or acquired by the first terminal device 10(N) into multiple packets and outputs them to a client device. The client device (corresponding to the "communication device") distributes the multiple packets received from the first terminal device 10(N) to one or more communication lines (1 to L) (L: the total number of communication lines) and transmits them to a server device (corresponding to the "counterparty device"). The server device rearranges multiple packets received from one or more communication lines to restore the original data, and transmits them to a second terminal device 20 (M) (corresponding to the "destination device"), which is the destination specified by the first terminal device 10 (N).

[0019] Packets transmitted from a client device are assigned a first sequence number, which is a number incremented in the order of packets transmitted for each communication line, and a second sequence number, which is a number incremented in the order of packets constituting the data for each data flow. The data flow is identified based on, for example, the IP address and port number of the first terminal device 10(N) as the source (together referred to as "source device information") and the IP address and port number of the second terminal device 20(M) as the destination (together referred to as "destination device information"). In addition, a line number identifying the line and a flow identification number identifying the flow may be included. This allows the server device to restore the data order of packets received from the client device based on the second sequence number, etc., and transmit them to the second terminal device 20(M).

[0020] The multiple communication lines may be communication lines using the same communication method or communication lines using different communication methods. For example, examples of wireless communication lines include IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), W-CDMA (Wideband Code Division Multiple Access), HSPA (High Speed ​​Packet Access), LTE (Long Term Evolution), LTE-A (Long Term Evolution Advanced), 4G, 5G, etc., or DSRC (Dedicated Short Range Communication). In each embodiment, it is assumed that all of the multiple communication lines are wireless communication lines, but some or all of them may be wired communication lines. Examples of wired communication lines include LANs (Local Area Networks) such as Ethernet (registered trademark), the Internet, optical fiber lines, and fixed telephone lines.

[0021] Specific examples of the first terminal device 10(N) and the second terminal device 20(M) will be described later in the embodiments using FIG. 4. The term "terminal" for the first terminal device 10(N) and the second terminal device 20(M) refers to the starting point and ending point for data generation and usage, and does not limit the form of the device. For example, even a large-scale server device can be called a terminal device for data generation or usage. The client device distributes and transmits multiple packets to one or more communication lines, and the method of distribution will be described in each embodiment.

[0022] The first terminal device 10(N) and the client device may be integrated. Also, in this example, the first terminal device 10(N) divides data into multiple packets and outputs them to the client device, but the client device may receive data from the first terminal device 10(N) and divide it into multiple packets. Also, the second terminal device 20(M) and the server device may be integrated.

[0023] In this example, when data is transmitted from a client device to a server device using an uplink, the client device corresponds to the communication device 100 in each embodiment, and the server device corresponds to the counterpart device 200. In this case, the first terminal device 10(N) corresponds to the source device in each embodiment, and the second terminal device 20(M) corresponds to the destination device in each embodiment. Conversely, when data is transmitted from a server device to a client device using a downlink, the server device corresponds to the communication device 100 in each embodiment, and the client device corresponds to the counterpart device 200. In this case, the second terminal device 20(M) corresponds to the source device in each embodiment, and the first terminal device 10(N) corresponds to the destination device in each embodiment. In either case, the communication device 100 and the counterpart device 200 together constitute the communication system 1 in each embodiment. In the following description, an example will be described in which an uplink is used. In the embodiments described below, the first terminal device 10(N) is referred to as the source device, and the second terminal device 20(M) is referred to as the destination device.

[0024] Next, a case where the communication device 100 is mounted on a vehicle will be described using FIG. 2 . The communication device 100 is included in an electronic control system S consisting of multiple electronic control units (ECUs) mounted on a vehicle, which is a "mobile body," and is responsible for communication inside and outside the vehicle. The communication device 100 stores data generated by an application running on the ECU or data acquired by a sensor in multiple packets and transmits the packets to a counterpart device 200 outside the vehicle. In this case, the ECU or sensor corresponds to the "transmitting device." Note that the communication device 100 itself may also be in the form of an ECU, such as a communication ECU or a TCU (Telematics Control Unit) with a communication module. Here, a "mobile body" refers to a movable object, and may move at any speed. This also naturally includes a stationary moving body. Examples include, but are not limited to, automobiles, motorcycles, bicycles, pedestrians, ships, aircraft, and objects mounted on these. "Mounted" includes not only cases where the device is directly fixed to the moving body, but also cases where the device is not fixed to the moving body but moves along with the moving body. For example, it may be carried by a person riding on a moving object, or may be carried on cargo placed on a moving object.

[0025] The counterpart device 200 transmits the received data to, for example, an application server (corresponding to a "destination device"), and the application server then executes various applications using the received data.

[0026] In each embodiment, the communication device 100 can perform communication in parallel using, for example, multiple 5G lines operated by different communication carriers, or can perform communication in parallel using communication lines of wireless communication methods including 5G, 4G, and Wi-Fi. Of course, the types and number of communication lines are arbitrary.

[0027] The data transmitted from the communication device 100 to the counterpart device 200 may include, but is not limited to, image information acquired by an in-vehicle camera or location information acquired by a GPS sensor. In addition to data, the object to be transmitted may also be software or a program itself.

[0028] 2 illustrates a case in which the communication device 100 is mounted on a vehicle and the counterpart device 200 is installed outside the vehicle, but the locations where the communication device 100 and the counterpart device 200 are installed are not limited to this. That is, the communication device 100 may not be mounted on a vehicle, but may be installed, for example, inside a building or outdoors. The counterpart device 200 may also be mounted on a vehicle. Of course, the communication device 100 and the counterpart device 200 do not have to be mounted on both vehicles, and may be mounted on different vehicles, or both may be mounted on the same vehicle. When mounted on different vehicles, the communication device 100 and the counterpart device 200 may communicate with each other using, for example, vehicle-to-vehicle communication.

[0029] 3 is a block diagram showing the configuration of the communication device 100 according to this embodiment. The communication device 100 includes a first receiving unit 101, a required characteristic information storage unit 102, a required characteristic determination unit 103, a policy characteristic information storage unit 104, a policy determination unit 105, a transmission control unit 106, second transmitting units 107-1 to 107-L, second receiving units 108-1 to 108-L, a reception control unit 109, a first transmitting unit 110, a policy characteristic information update unit 111, and a policy characteristic information change unit 112.

[0030] Communication device 100 is a device capable of communicating with counterpart device 200 "connected" to a destination device using one or more communication lines in order to transmit packets containing data received from a source device to the destination device. With regard to packets that communication device 100 transmits to counterpart device 200, data received from the source device may be stored in multiple packets by communication device 100 or another device, or data may be stored in multiple packets by the source device. Here, "connected" includes not only direct connection but also indirect connection via several devices.

[0031] The communication device 100 can be configured with a general-purpose CPU (Central Processing Unit), volatile memory such as RAM, non-volatile memory such as ROM, flash memory, or hard disk, various interfaces, and an internal bus connecting these. The communication device 100 can be configured to perform the functions of each functional block shown in Figure 3 by executing software on this hardware.

[0032] The first receiving unit 101 (corresponding to the "receiving unit") receives a packet from the source device. When packets are generated within the communication device 100 rather than in the source device, data received from the source device is stored in a packet in a packet storage unit (not shown) provided in front of the first receiving unit 101, and the packet output from the packet storage unit is received by the first receiving unit 101. Even in this case, from the perspective of the first receiving unit 101, it can be said that a packet has been received from the first terminal device 10(N).

[0033] The required characteristic information storage unit 102 stores required characteristic information that links source device candidates and destination device candidates with required characteristic candidates. The required characteristic information storage unit 102 may be a volatile memory such as a RAM, or a non-volatile memory such as a flash memory or a hard disk.

[0034] The method for defining the required characteristic information and its contents will be explained using Figure 4. Generally, there may be multiple types of data used by a destination device. In such cases, the type of data can be identified by the combination of the source device and the destination device. For example, if a remote driving application that controls a vehicle in real time while viewing camera footage from a remote location is running on a server device, video data and location information are transmitted from the vehicle to the server device. In this case, the destination device for the video data and location information is the server device, while the source device for the video data is the camera or an ECU that manages the camera footage, and the source device for the location information is the GPS or an ECU that manages the location information.

[0035] For example, in a remote driving application, control is primarily performed using camera footage, and location information is used as supplementary information to complement the camera footage. In this case, since video data is large and requires real-time performance, wide bandwidth and low latency are desirable, but packet loss is acceptable as long as it does not distort the screen. Therefore, the candidate required characteristics are determined as follows: speed 15 Mbps, latency 120 ms, and success rate 90%. The success rate is the probability of successful transmission and reception, and is calculated by subtracting the packet loss rate from 100%. In contrast, since location information is small in size, a low communication speed is not a problem, but since it complements the camera footage, real-time performance similar to that of video data is required. Since small-sized data is generally more susceptible to data loss, packet loss should be kept as low as possible. Therefore, the candidate required characteristics are determined as follows: speed 2 Mbps, latency 120 ms, and success rate 95%.

[0036] Using yet another example, the method and content of the required characteristic information will be described. For example, in the case of a remote conference system, video data and audio data are transmitted from the terminal device of a participant participating in a conference to a server device, and the server device executing the remote conference system receives the data and forwards it to the terminal devices of other participants. In this case, the destination device for the video data and audio data is the server device or the terminal device of the other participant, such as a personal computer or smartphone, while the source device for the video data is a camera or the personal computer or smartphone of the participant who manages the video data, and the source device for the audio data is a microphone or the personal computer or smartphone of the participant who manages the audio data.

[0037] The remote conference system shares the same commonality as the remote driving application in the previous example in that it uses camera footage, but the video data in the remote conference system can be less real-time than that of the remote driving application, and some degree of screen disturbance is acceptable. Therefore, the candidate required characteristics are set to a speed of 10 Mbps, a delay of 200 ms, and a success rate of 85%. In contrast, audio data is smaller in size than video data, so a lower communication speed is not a problem. However, due to the nature of conferences, real-time performance is required to ensure smooth conversation, and audio interruptions are unacceptable. However, a lack of synchronization with the video does not pose a major problem. Therefore, the candidate required characteristics are set to a speed of 4 Mbps, a delay of 100 ms, and a success rate of 95%.

[0038] Another example is a big data analysis application that collects various sensor data and logs from a vehicle and performs statistical processing. In this case, the destination device for the logs is a server device, and the source device for the logs is a security sensor or an ECU that manages the logs. Since logs are data used for statistical processing, the requirements for speed and latency can be relaxed, but packet loss should be small because it affects the results of the statistical processing. Furthermore, since a huge amount of data needs to be transmitted, communication costs should be as low as possible. Therefore, the candidate required characteristics are set as follows: a speed of 7 Mbps, a latency of 300 ms, a success rate of 95%, and a communication cost of 2 yen / GB or less.

[0039] FIG. 5 is a diagram showing a specific example of the content of required characteristic information. As shown in FIG. 4, FIG. 5 associates and stores required characteristic candidates with predetermined source device candidates and destination device candidates. In FIG. 5, the source device candidate is recorded with the address and port of the source device, the destination device candidate is recorded with the address and port of the destination device, and protocol candidates, which are protocols used for communication. Then, the source device candidate and the destination device candidate are associated with required characteristic candidates, which indicate required characteristics required for communication between the source device candidate and the destination device candidate. In FIG. 5, speed (Mbps), delay (ms), success rate (%), and other indices are recorded as indicators of the required characteristic candidates. Of course, this is merely an example, and other indices may be recorded as required characteristic candidates. Instead of the success rate (%), a packet loss rate (%) may be recorded.

[0040] 5 , in accordance with the example described at the beginning of FIG. 4 , the address (x.x.x.x) and port number (100) of the ECU that manages the camera video (the source device), the address (a.a.a.a) and port number (100) of the server device that is the destination device, and the required characteristics required by the protocol (TCP) are recorded, including speed (15 Mbps), delay (120 ms), and success rate (90%). Also, the address (y.y.y.y) and port number (100) of the ECU that manages the location information (the source device), the address (a.a.a.a) and port number (200) of the server device that is the destination device, and the required characteristics required by the protocol (TCP) are recorded, including speed (2 Mbps), delay (120 ms), and success rate (95%).

[0041] Note that Figure 5 shows an example in which both source device candidates and destination device candidates are recorded, but if the required characteristics can be determined using only the source device candidates or only the destination device candidates, it is also possible to record only either the source device candidates or the destination device candidates.

[0042] In Fig. 5, the source device candidates, destination device candidates, protocol candidates, and required characteristic candidates defined as in Fig. 4 are recorded, but in addition, rows recording only protocol candidates and required characteristic candidates, and rows recording only required characteristic candidates, such as the bottom three rows in Fig. 5, are also included. How to use this will be described later in the section on required characteristic determination unit 103.

[0043] 5 indicate ideal values. In this embodiment, a measure having a measure characteristic closest to the ideal value is adopted, as will be described later. In addition, in the second embodiment, an example will be described in which the required characteristic candidate indicates a limit value.

[0044] The required characteristics determination unit 103 determines required characteristics for communication to transmit a packet to the other device 200 based on the packet received by the first receiving unit 101. More specifically, the required characteristics for communication are determined based on source device information indicating a source device "identified" from the packet received by the first receiving unit 101 and destination device information indicating a destination device "identified" from the packet. Furthermore, the required characteristics may be determined based on a protocol "identified" from the packet. Methods for obtaining source device information and destination device information from a packet include, for example, using information indicating a source device or a destination device included in the received packet. Furthermore, the protocol may be obtained using information indicating a protocol included in the received packet. Alternatively, the source device information and destination device information may be estimated from the type of data included in the packet, the protocol used, the packet frame structure, and the packet transmission and reception time. Here, "identified" includes not only cases where the information included in the packet is directly or indirectly used to identify the device, but also cases where the information other than the information included in the packet, such as the packet structure or the packet transmission and reception time, is used to identify the device.

[0045] According to this embodiment, the required characteristics determination unit 103 determines required characteristics using required characteristics information stored in the required characteristics information storage unit 102 as shown in Fig. 5. For example, if the source device information included in the packet is an address (x.x.x.x) and a port number (100), the destination device information is an address (a.a.a.a) and a port number (100), and the protocol is TCP, these match the source device candidate, destination device candidate, and protocol candidate of ID (1) in Fig. 5, so the required characteristics determination unit 103 determines the corresponding required characteristics candidates to be a speed (15 Mbps), a delay (120 ms), and a success rate (90%).

[0046] If the required characteristic information does not contain a combination of source device candidate and destination device candidate that matches the combination of source device information and destination device information, one of the required characteristic candidates ID(101) to ID(103) is used. For example, if the protocol can be identified from the packet, the required characteristic candidate ID(101) or ID(102) is determined as the required characteristic. If the protocol cannot be identified either, the required characteristic candidate ID(103) is determined as the required characteristic.

[0047] The policy characteristic information storage unit 104 stores policy characteristic information that links multiple policy candidates with policy characteristic candidates that can be realized by each of the policy candidates. Like the required characteristic information storage unit 102, the policy characteristic information storage unit 104 may be either a volatile memory such as a RAM or a non-volatile memory such as a flash memory or a hard disk.

[0048] FIG. 6 is a diagram showing a specific example of the contents of the policy characteristic information. FIG. 6 shows a case where there are two multiple communication lines. In FIG. 6, the policy candidates are candidate communication methods using one or multiple communication lines. When using one or multiple communication lines, there are three possible control methods for combinations: simple transmission, bandwidth synthesis transmission, and redundant transmission. Simple transmission is a control method for transmitting packets using one of multiple communication lines. Bandwidth synthesis transmission is a control method for allocating packets to two or more of multiple communication lines for transmission. Redundant transmission is a control method for transmitting the same packet using two or more communication lines.

[0049] In the example of Figure 6, the candidate measures are defined by the dependency rate of each communication line. The dependency rate is an index that indicates what proportion of the amount of data to be transmitted is entrusted to that communication line. For example, if packets to be transmitted are generated at 5 Mbps and the dependency rate of a certain communication line is 50%, transmission will be performed over that communication line with a limit of 2.5 Mbps. The dependency rate can also be expressed as the reliability of each line.

[0050] In the case of Figure 6, there are two communication lines, so in the case of simple transmission, there are two candidate policies, #1 and #2. In the case of redundant transmission, there is only one candidate policy, #6. In the case of bandwidth synthesis transmission, the number of policies varies depending on the granularity of the dependency rate. For example, if the granularity is 50%, there are three candidate policies, #3 to #5. Then, candidate policy characteristics that can be realized by using the communication lines with each candidate policy are recorded. The candidate policy characteristics can be calculated if the speed, delay, success rate, and other indicators when each communication line is used alone are known. Note that while the candidate policy characteristics in Figure 6 indicate expected values ​​of the policy characteristics, actual values ​​may be shown instead. Furthermore, if the line usage rate is uniquely determined, the expected values ​​and actual values ​​at that usage rate may be shown.

[0051] The number of communication lines may be three or more. In this case, some of the communication lines may be used for bandwidth synthesis transmission, and the remaining lines may be used for redundant transmission.

[0052] 6, the policy candidate is classified by dependency rate, but it may be classified by utilization rate. In this case, too, in the case of bandwidth synthesis transmission, the policy candidate may be set at the granularity of the number of communication lines to be used and the utilization rate of each communication line.

[0053] The policy determination unit 105 determines a policy, which is a "combination" of one or more communication lines to be used for communication, based on the required characteristics determined by the required characteristics determination unit 103. Alternatively, the policy determination unit 105 may determine a policy, which is a "combination" and "proportion" of one or more communication lines to be used for communication, based on the required characteristics determined by the required characteristics determination unit 103. The proportion may be either the proportion of packets allocated to each communication line or the proportion of resources used for each communication line. According to this embodiment, the policy determination unit 105 uses policy characteristic information stored in the policy characteristic information storage unit 104 as shown in FIG. 6 to determine, as a policy, a policy candidate linked to a policy characteristic candidate having the shortest "distance" from the required characteristics. Here, the "combination" includes a combination of two or more communication lines as well as the use of a single communication line. The "proportion" includes 0% and 100%. The "distance" indicates the degree of deviation between the required characteristic and the policy characteristic candidate, and can be defined, for example, by a norm that is the length of a geometric vector on a plane or in space.

[0054] FIG. 7 is a diagram illustrating the calculation performed by the measure determination unit 105 of this embodiment to determine the inter-vector distance. When the required characteristic and the measure characteristic candidate are treated as vectors, the measure determination unit 105 of this embodiment determines the measure characteristic candidate with the smallest inter-vector distance. For example, in FIG. 7, the measure characteristic candidate indicated by #3 has the smallest inter-vector distance from the required characteristic, so the measure candidate corresponding to #3 is determined as the measure. Note that, if the required characteristic is Cr and the measure characteristic of the measure characteristic candidate is C(#), the distance d(Cr, C(#)) between the required characteristic Cr and the measure characteristic C(#) can be calculated as follows: d(Cr, C(#)) = ||Cr - C(#)||. ||Cr - C(#)|| may be calculated as the square root of the sum of the squares of Cr and C(#), or other calculations may be used.

[0055] The policy decision unit 105 may notify the source device if the distance d between the required characteristic Cr and the policy characteristic C(#) linked to the policy is greater than a predetermined distance. In such a case, there is a possibility that packets cannot be transmitted in stable communication. Therefore, notifying the source device in advance can trigger the source device to take measures. Here, the "predetermined distance" may be a constant value or a variable value that varies depending on conditions. "Greater than" includes both cases where the comparison targets are equal (≦) and cases where they are not equal (<).

[0056] Transmission control unit 106 distributes packets to be transmitted to each communication line based on the policy decided by policy decision unit 105. Then, multiple second transmission units 107-1 to 107-L (L: number of communication lines) (corresponding to "transmission unit") are connected to communication lines 1 to 107-L, and transmit the packets distributed to each unit to counterparty device 200. Note that when the policy decided by policy decision unit 105 is simple transmission, packets are not distributed to communication lines that are not in use, and second transmission units 107 connected to communication lines that are not in use do not transmit packets.

[0057] The second receiving units 108-1 to 108-L receive actual measurement values ​​of communication characteristics measured and transmitted by the counterpart device 200. In this embodiment, the actual measurement values ​​include speed (Mbps), delay (bps), and success rate (%). In addition, the second receiving units 108-1 to 108-L also receive data transmitted from the destination device to the source device.

[0058] The reception control unit 109 outputs the actual measurement values ​​of the communication characteristics received by the second reception units 108-1 to 108-L to the policy characteristic information update unit 111. In addition, the reception control unit 109 rearranges the packets received by the second reception units 108-1 to 108-L and outputs them to the first transmission unit 110.

[0059] The first transmitting unit 110 transmits the packets rearranged by the reception control unit 109 to the source device.

[0060] The policy characteristic information update unit 111 updates the policy characteristic candidates of the policy characteristic information by using actual measurement values ​​of communication characteristics received from the counterpart device 200. For example, the policy characteristic information update unit 111 periodically receives communication speed (Mbps), delay (ms), and success rate (%) from the counterpart device 200 and updates the policy characteristic candidates of the policy characteristic information by calculating a moving average for each. Alternatively, the policy characteristic candidates of the policy characteristic information are updated by filtering each of them taking into account an observation error.

[0061] The policy characteristic information change unit 112 changes the policy characteristic candidates of the policy characteristic information based on at least one input of the vehicle speed, the vehicle position, and the current time. For example, a set of multiple policy characteristic candidates is prepared in advance for one policy candidate, and the set of policy characteristic candidates is changed by appropriately switching based on the input information.

[0062] For example, the faster the vehicle speed, the lower the success rate of the policy characteristic candidate is switched to. The vehicle speed can be obtained by inputting the vehicle speed detected by a wheel speed sensor or position information measured using GNSS. For example, when the vehicle moves to a specific location, the policy characteristic candidate with a slower communication speed is switched to. The vehicle position can be obtained by inputting position information measured using GNSS. For example, when it is a time period when there is a high traffic congestion of vehicles on the road, the policy characteristic candidate with a slower communication speed is switched to. The current time can be obtained by inputting the current time measured using a clock installed in the vehicle or GNSS. Additionally, when connected using a specific communication standard, the policy characteristic candidate with a slower communication speed may be switched to.

[0063] In this embodiment, the policy characteristic information update unit 111 and the policy characteristic information change unit 112 may have any configuration.

[0064] 8 is a block diagram showing the configuration of the counterparty device 200 in this embodiment. The counterparty device 200 has receiving units 201-1 to 201-L, a communication characteristics measurement unit 202, transmitting units 203-1 to 203-L, and an alignment unit 204.

[0065] The receiving units 201-1 to 201-L receive packets transmitted from the second transmitting units 107-1 to 107-L of the communication device 100 via the respective communication lines.

[0066] Communication characteristic measurement unit 202 measures the communication characteristics of each communication line based on packets received by receiving units 201-1 to 201-L. For example, communication characteristic measurement unit 202 measures the communication speed (Mbps) based on the amount of data of packets received in a predetermined period, the packet delay (ms) based on transmission time information included in the packets and the reception time at which the packets were received, and the success rate (%) based on the number of packets transmitted from communication device 100 and the number of packets received by receiving units 201-1 to 201-L. The number of packets transmitted from communication device 100 can be found using the first sequence number and second sequence number included in the packets.

[0067] Transmitting units 203-1 to 203-L transmit the actual measured values ​​of the communication characteristics measured by communication characteristics measuring unit 202 to communication device 100. For example, the actual measured values ​​of the communication characteristics are stored in packets and transmitted. In addition, transmitting units 203-1 to 203-L also transmit data received from a destination device by a receiving unit (not shown) and transmitted from the destination device to the source device.

[0068] Alignment unit 204 rearranges the packets received by receiving units 201-1 to 201-L based on the second sequence number etc. included in each packet, and then transmits the packets from a transmitting unit (not shown) to a destination device.

[0069] (3) Operation of Communication Device 100 Next, the operation of communication device 100 will be described with reference to Figures 9 to 11. Figures 9 to 11 not only show the communication method executed by communication device 100, but also show the processing procedure of a communication program that can be executed by communication device 100. These processes are not limited to the order shown in Figures 9 to 11. In other words, the order may be changed as long as there are no constraints, such as a relationship in which a certain step uses the result of the previous step.

[0070] FIG. 9 is a flow diagram illustrating the overall operation of the communication device 100. The first receiving unit 101 receives a packet from a source device (S101). The required characteristics determining unit 103 determines required characteristics for communication based on source device information indicating the source device identified from the packet received in S101 and destination device information indicating the destination device identified from the packet received in S101 (S102). The strategy determining unit 105 determines a strategy, which is a combination of one or more communication lines to be used for communication, based on the required characteristics determined in S102 (S103). The transmission control unit 106 distributes packets to each communication line based on the strategy determined in S103 (S104). The second transmitting units 107-1 to 107-L transmit the packets distributed in S104 using each communication line (S105).

[0071] FIG. 10 is a flow diagram illustrating the details of the operation of the required characteristics determination unit 103, S102. Note that the numbers in parentheses next to the required characteristics candidates indicate the IDs in FIG. 5. The required characteristics determination unit 103 identifies the source device, destination device, and protocol from the packet received in S101 (S111). The required characteristics determination unit 103 reads required characteristics information from the required characteristics information storage unit 102 (S112). The required characteristics determination unit 103 determines whether the source device, destination device, and protocol identified in S111 are all included in the required characteristics information read in S112 (S113). If included, the required characteristics determination unit 103 uses the required characteristics information to determine the required characteristics candidate (1-) corresponding to the source device, destination device, and protocol as the required characteristics Cr (S114). If not included, the process proceeds to S115. The required characteristics determination unit 103 determines whether the protocol identified in S111 is included in the required characteristics information read in S112 (S115). If included, the required characteristics determination unit 103 uses the required characteristics information to determine the required characteristics candidate (101, 102) corresponding to the protocol as the required characteristics Cr (S116). If not included, the required characteristics determination unit 103 determines the required characteristics candidate (103) as the required characteristics Cr (S117).

[0072] 11 is a flow diagram illustrating the details of the operation of S103, which is the operation of the policy determination unit 105. The policy determination unit 105 assigns an initial value of a policy candidate as a policy p (S121) and calculates a distance d between the policy characteristic candidate C(p) of the policy p and the required characteristic Cr (S122). The policy determination unit 105 calculates a distance d(i) between the first (i=1) policy characteristic candidate C(i) and the required characteristic Cr (S123, S124). If the distance d(i) is equal to or greater than the distance d (S125: No), the program increments i (S129) and returns to the processing of S124. If the distance d(i) is smaller than the distance d (S125: Yes), the policy candidate p(i) is set as the policy p (S126) and the distance d(i) is set as the distance d (S127). If i has not reached the number N of all the candidate measures (S128: No), i is incremented (S129) and the process returns to S124. If i has reached the number N of all the candidate measures (S128: Yes), the process determines the distance d between the measure p and the candidate measure characteristic C(p) of the measure p and the required characteristic Cr, and ends the process.

[0073] (4) Summary As described above, the communication device 100 of this embodiment determines required characteristics for communication based on source device information and destination device information, and distributes packets to each line based on these required characteristics, thereby enabling multi-link communication suitable for the type of packet, the type of data contained in the packet, etc. The communication device 100 of this embodiment further determines required characteristics for communication based on a protocol identified from the packet, thereby enabling more accurate required characteristics to be determined. The communication device 100 of this embodiment determines, as a policy, a policy candidate linked to a policy characteristic candidate that is closest to the required characteristics, so it is possible to identify a combination and ratio of communication lines that achieves characteristics closest to the required characteristics, and to transmit packets with communication characteristics closest to the required characteristics.

[0074] (5) Modification 1 of Embodiment 1 In the first embodiment, the required characteristic candidates are ideal values, as shown in FIG. 5 . Therefore, the measure determination unit 105 determines, as a measure, a policy characteristic candidate linked to a policy characteristic candidate having the smallest distance from the required characteristic. However, if the required characteristic candidate is not an ideal value but a limit value, the determination method of the measure determination unit 105 in the first embodiment may determine, as a measure, a policy candidate linked to a policy characteristic candidate below the limit value. Therefore, in this modification, a case where the required characteristic candidate is a limit value will be described.

[0075] The communication device 100 of this modification has the same configuration as the communication device 100 of the first embodiment, so Fig. 3 and the description of the first embodiment will be cited. Below, the configuration and processing that differ from the first embodiment will be described.

[0076] Fig. 12 is a diagram showing a specific example of the content of the required characteristic information of this modified example. The difference from Fig. 5 is that the required characteristic candidate index in Fig. 12 indicates a limit value, so that information on whether it is above or below a predetermined value is added.

[0077] Then, the measure determination unit 105 uses the measure characteristic information stored in the measure characteristic information storage unit 104 as shown in Figure 6 to determine as the measure the measure candidate linked to the measure characteristic candidate that has the smallest ``distance'' from the required characteristic among the measure candidates linked to the measure characteristic candidate that satisfies the required characteristic as the limit value.

[0078] 13 is a diagram illustrating the calculation performed by the measure determination unit 105 of this modified example to determine the inter-vector distance. As in the first embodiment, the measure determination unit 105 of this modified example determines the measure characteristic candidate with the smallest inter-vector distance. However, since the required characteristic Cr is a limit value, even if the measure characteristic candidate corresponding to #3 has the smallest inter-vector distance from the required characteristic Cr, the vector of the measure characteristic candidate corresponding to #3 is in the NG region and does not satisfy the required characteristic as the limit value. In this modified example, the measure candidate that satisfies the required characteristic Cr as the limit value and is linked to the measure characteristic candidate corresponding to #1 with the smallest inter-vector distance from the required characteristic Cr is determined as the measure.

[0079] As in the first embodiment, the required characteristics may be set as ideal values, and a threshold value may be set as a limit value. In this case, the threshold value may also be considered as part of the required characteristics.

[0080] As described above, according to the communication device of this modified example, the policy candidate linked to the policy characteristic candidate that is closest to the required characteristic among the policy characteristic candidates that satisfy the required characteristic as the limit value is determined as the policy, so that packets can be transmitted with the communication characteristics required for transmitting the packets, and communication failures due to packet loss or congestion can be avoided.

[0081] (6) Variation 2 of Embodiment 1 In Embodiment 1, the required characteristics are assumed to be ideal values, and the policy candidate linked to the policy characteristic candidate that is the smallest distance from the required characteristics is determined as the policy. However, in addition to this condition, it is also possible to limit the policy by similarity.

[0082] That is, the policy decision unit 105 determines, as a policy, the policy candidate linked to the policy characteristic candidate with the smallest "distance" from the required characteristic among the policy candidates linked to the policy characteristic candidates whose similarity to the required characteristic is within a predetermined range, using the policy characteristic information stored in the policy characteristic information storage unit 104 as shown in Fig. 6. If the required characteristic is Cr and the policy characteristic of the policy characteristic candidate is C(#), the similarity cos θ can be calculated as follows: cos θ = Cr·C(#) / ||Cr||·||C(#)||

[0083] 14 is a diagram illustrating the calculation performed by the measure determiner 105 of this modified example to determine the inter-vector distance. As in the first embodiment, the measure determiner 105 of this modified example determines the measure characteristic candidate with the smallest inter-vector distance. However, even if the measure characteristic candidate corresponding to #2 has the smallest inter-vector distance from the required characteristic Cr, the vector of the measure characteristic candidate corresponding to #2 is in the NG region, so the similarity is outside the predetermined range and does not satisfy the required characteristic. In this modified example, the measure candidate linked to the measure characteristic candidate corresponding to #1, whose similarity to the required characteristic Cr is within the predetermined range and whose inter-vector distance from the required characteristic Cr is smallest, is determined as the measure.

[0084] As described above, according to the communication device of this modified example, among the policy candidate linked to the policy characteristic candidate whose similarity to the required characteristic is within a predetermined range, the policy candidate linked to the policy characteristic candidate that is closest to the required characteristic is determined as the policy.Therefore, packets can be transmitted with the communication characteristics required for transmitting the packets, and communication failures due to packet loss or congestion can be avoided.

[0085] 3. Summary The features of the communication devices and the like in each embodiment of the present disclosure have been described above.

[0086] The terms used in each embodiment are merely examples and may be replaced with synonymous terms or terms having the same functions.

[0087] The block diagrams used to explain the embodiments classify and organize the device configuration by function. The blocks representing each function can be realized by any combination of hardware or software. Furthermore, because they represent functions, the block diagrams can also be understood as disclosures of method inventions and program inventions that realize the methods.

[0088] The order of the functional blocks that can be understood as the processes, flows, and methods described in each embodiment may be changed as long as there are no constraints, such as one step utilizing the results of another step that precedes it.

[0089] The terms first, second, through Nth (N is an integer) used in each embodiment and in the claims are used to distinguish between two or more configurations or methods of the same type, and do not limit the order or superiority or inferiority.

[0090] Examples of the form of the communication device and the counterpart device of the present disclosure include the following: Examples of the form of components include semiconductor elements, electronic circuits, modules, and microcomputers; Examples of the form of semi-finished products include electronic control devices (ECUs (Electric Control Units)) and system boards; Examples of the form of finished products include mobile phones, smartphones, tablets, personal computers (PCs), workstations, and servers; and Other devices with communication functions, such as video cameras, still cameras, and car navigation systems.

[0091] Furthermore, necessary functions such as an antenna and a communication interface may be added to the communication device.

[0092] The communication device of the present disclosure is expected to be used, particularly on the server side, to provide various services, and the communication device of the present disclosure, the method of the present disclosure, and / or the program of the present disclosure will be used in providing these services.

[0093] In addition, the present disclosure can be realized not only by dedicated hardware having the configuration and functions described in each embodiment, but also by a combination of a program for realizing the present disclosure recorded on a recording medium such as a memory or a hard disk, and general-purpose hardware having a dedicated or general-purpose CPU and memory that can execute the program.

[0094] A program stored in a non-transient physical recording medium (for example, an external storage device (hard disk, USB memory, CD / BD, etc.) or an internal storage device (RAM, ROM, etc.)) of dedicated or general-purpose hardware can be provided to the dedicated or general-purpose hardware via the recording medium, or via a communication line from a server without using a recording medium. This makes it possible to always provide the latest functions through program upgrades.

[0095] The communication device of the present disclosure may be used in a mobile phone or smartphone that supports multi-SIM.

Claims

1. A communication device (100) capable of communicating with a counterpart device connected to a destination device using one or more communication lines in order to transmit a packet including data received from a source device to the destination device, the communication device (100) comprising: a receiving unit (101) that receives the packet from the source device; a required characteristics determining unit (103) that determines required characteristics for the communication based on source device information indicating the source device identified from the packet and destination device information indicating the destination device identified from the packet; a strategy determining unit (105) that determines a strategy, which is a combination of one or more of the communication lines to be used for the communication, based on the required characteristics; a transmission control unit (106) that distributes the packet to each communication line based on the strategy; and a plurality of transmission units (107) connected to each of the communication lines and that transmit the packet.

2. The communication device according to claim 1, wherein the required characteristics determination unit determines the required characteristics based on a protocol identified from the packet.

3. The communication device of claim 1 further comprises a required characteristic information storage unit (102) that stores required characteristic information linking source device candidates and destination device candidates with required characteristic candidates, and the required characteristic determination unit uses the required characteristic information to determine the required characteristic candidate corresponding to the source device information and the destination device information as the required characteristic.

4. The communication device of claim 1, further comprising a policy characteristic information storage unit (104) that stores policy characteristic information linking multiple policy candidates with policy characteristic candidates that can be realized by each of the policy candidates, and the policy determination unit uses the policy characteristic information to determine as the policy the policy candidate linked to the policy characteristic candidate that has the smallest distance from the required characteristic.

5. The communication device of claim 4, wherein the policy determination unit uses the policy characteristic information to determine, as the policy, the policy candidate linked to the policy characteristic candidate that has the smallest distance from the required characteristic among the policy candidates linked to the policy characteristic candidate that satisfies the required characteristic as a limit value.

6. The communication device of claim 4, wherein the policy determination unit uses the policy characteristic information to determine, as the policy, the policy candidate linked to the policy characteristic candidate that has the smallest distance from the required characteristic among the policy candidates linked to the policy characteristic candidate whose similarity to the required characteristic is within a predetermined range.

7. The communication device according to any one of claims 4 to 6, wherein the policy decision unit notifies the transmission source device when the distance between the required characteristic and the policy candidate linked to the policy is greater than a predetermined distance.

8. A communication device according to any one of claims 4 to 6, wherein the strategy determination unit determines the strategy from among simple transmission, which transmits the packet using a single communication line, bandwidth synthesis transmission, which distributes the packet over multiple communication lines and transmits it, and redundant transmission, which transmits the same packet over multiple communication lines.

9. The communication device according to claim 1, wherein the policy determination unit determines the policy, which is a combination and ratio of one or more communication lines to be used for the communication, based on the required characteristics.

10. A communication device according to any one of claims 4 to 6, further comprising a policy characteristic information update unit (111) that updates the policy characteristic candidates of the policy characteristic information using actual measurement values ​​of communication characteristics received from the counterpart device.

11. A communication device according to any one of claims 4 to 6, wherein the communication device is mounted on a moving body, and further comprises a policy characteristic information change unit (112) that changes the policy characteristic candidates of the policy characteristic information based on at least one of the speed of the moving body, the position of the moving body, and the current time.

12. A communication method executed by a communication device (100) capable of communicating with a counterpart device connected to a destination device using one or more communication lines in order to transmit a packet containing data received from a source device to the destination device, the method comprising: receiving the packet from the source device (S101); determining required characteristics for the communication based on source device information indicating the source device identified from the packet and destination device information indicating the destination device identified from the packet (S102); determining a strategy, which is a combination of one or more communication lines to be used for the communication, based on the required characteristics (S103); allocating the packet to each communication line based on the strategy (S104); and transmitting the packet using each communication line (S105).

13. A communications program executable by a communications device (100) capable of communicating with a counterpart device connected to a destination device using one or more communications lines in order to transmit a packet containing data received from a source device to the destination device, the communications program causing the communications device to: receive the packet from the source device (S101); determine required characteristics for the communication based on source device information indicating the source device identified from the packet and destination device information indicating the destination device identified from the packet (S102); determine a strategy, which is a combination of one or more communications lines to be used for the communication, based on the required characteristics (S103); allocate the packet to each communications line based on the strategy (S104); and transmit the packet using each communications line (S105).

14. A communication system (1) comprising a communication device (100) and a counterpart device (200) that communicates with the communication device, wherein the communication device is capable of communicating with the counterpart device connected to a destination device using one or more communication lines in order to transmit a packet including data received from a source device to the destination device, and comprises: a receiving unit (101) that receives the packet from the source device; a required characteristics determining unit (103) that determines required characteristics for the communication based on source device information indicating the source device identified from the packet and destination device information indicating the destination device identified from the packet; a policy determining unit (105) that determines a policy, which is a combination of one or more communication lines to be used for the communication, based on the required characteristics; a transmission control unit (106) that distributes the packet to each communication line based on the policy; and a plurality of transmission units (107) connected to each communication line and that transmit the packet, wherein the counterpart device comprises: a receiving unit (201) that receives the packet; A communication system (1) comprising: a communication characteristic measurement unit (202) that measures communication characteristics of each of the communication lines based on the received packets; and a transmission unit (203) that transmits the communication characteristics to the communication device.

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