Communication device, communication program, and communication method

Abstract

To provide a configuration that can simultaneously achieve a uniform processing rate and an increased processing rate while reducing the processing and communication load.SOLUTION: A first communication device performs a descending process, a determining process, and an ascending process. In the descending process, the transmission rate of data transmitted to each of opposite communication devices is adjusted downward so that a difference in the processing rate of each of the opposite communication devices falls within a threshold regarding data 1 transmitted by the first communication device. In the determining process, it is determined whether or not a first start condition that the descending process related to the data 1 transmitted by the first communication device has been completed and a second start condition that the descending process related to data transmitted by another communication device has been completed are satisfied. In the ascending process, when it is determined that the first start condition and the second start condition are satisfied, the transmission rate of data transmitted to each of the opposite communication devices is uniformly increased.SELECTED DRAWING: Figure 5

Description

[Technical field]

[0001] The present invention relates primarily to a communication device that forms a communication network with a number of other communication devices. [Background technology]

[0002] Patent Document 1 discloses a network including multiple relay base station devices and a network manager device. The relay base station device measures the packet rate of the flow passing through itself and reports it to the network manager device. The network manager device determines an upper limit of the packet rate based on the reported packet rate and transmits it to the relay base station device. The relay base station device limits the transmission of packets passing through itself based on the upper limit of the received packet rate. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2011-160123 A Summary of the Invention [Problem to be solved by the invention]

[0004] In an environment where multiple communication devices communicate with each other, it is preferable to standardize the quality (amount of data) of the data being handled. However, the method of Patent Document 1 measures the packet rate for each flow individually and sets an upper limit for each flow individually, which generates a lot of processing and communication related to the measurement and setting, and therefore increases the processing and communication load.

[0005] The present invention has been made in view of the above circumstances, and a main object of the present invention is to provide a configuration capable of simultaneously realizing a uniform processing rate and an increased processing rate while reducing the processing and communication load.

[0006] The problem to be solved by the present invention has been described above. Next, the means for solving this problem and the effects thereof will be described.

[0007] According to a first aspect of the present invention, there is provided a communication device having the following configuration. That is, the communication device forms a communication network together with a plurality of other communication devices. The communication device includes a control unit and a communication unit. The control unit generates data to be transmitted to the other communication devices. The communication unit performs a process of transmitting the data generated by the control unit to any one or more other communication devices among the other communication devices, and a process of receiving from each of the other communication devices a processing rate, which is a processing amount per unit time when the other communication devices process data. The control unit performs a descending process, a determining process, and an ascending process. In the descending process, the transmission rate of the data to be transmitted to the other communication device is adjusted downward so that the difference in the processing rate of each of the other communication devices for the data transmitted by the communication unit falls within a threshold value. In the determining process, it is determined whether or not a first start condition that the descending process for the data transmitted by the communication unit has been completed and a second start condition that the descending process for the data transmitted by the other communication devices has been completed are satisfied. In the increase process, when it is determined that the first start condition and the second start condition are satisfied, the transmission rates of the data transmitted to each of the partner communication devices are uniformly increased.

[0008] The transmission rate is lowered once by the descending process to make the processing rate uniform, and then the transmission rate is increased uniformly by the ascending process, so that the processing rate can be made uniform and increased in speed. In addition, since multiple transmission rates are changed at once, the amount of processing can be reduced compared to when the transmission rate is changed for each individual communication path.

[0009] The communication device is preferably configured as follows: That is, the processing rate received by the communication unit from the other communication device includes the processing rate at which the other communication device processes data generated by the control unit and transmitted by the communication unit, and the processing rate at which the other communication device processes data generated by the other communication device and transmitted to the other communication device.

[0010] The communication device can obtain all the necessary information at once.

[0011] In the communication device, it is preferable that the control unit determines that the second start condition is satisfied when the processing rate for the data transmitted by the other communication device and, when the transmitting party is the same communication device, the processing rate for the data transmitted from each of the other communication devices is higher than the immediately preceding processing rate.

[0012] This allows the ascending process to be started even if the other communications device has started the ascending process first.

[0013] The communication device is preferably configured as follows: That is, the increase process includes at least a first stage and a second stage. After performing the first stage of the increase process, the control unit performs the second stage of the increase process after determining that the first stage is completed.

[0014] As a result, the processing rate is further increased after it has been uniformized, so that the processing rate is less likely to become non-uniform.

[0015] The communication device is preferably configured as follows: the first stage of the increase process is a process of increasing the processing rate to a value obtained by multiplying the processing rate by a coefficient, and the second stage of the increase process is a process of increasing the processing rate to a value obtained by multiplying the processing rate by the square of the coefficient.

[0016] The increase process can be multi-staged with simple processing. Also, the number of stages to which the increase process has progressed can be easily detected.

[0017] In the communication device, it is preferable that, after performing the increase process, the control unit performs the decrease process again when it determines that the increase process has failed.

[0018] If the processing rate is increased too much, it can be decreased.

[0019] In the communication device, it is preferable that the control unit performs the descending process again when it determines, after performing the increasing process, that the rate of decrease in the processing rate is greater than or equal to a threshold value or that the difference in the processing rates is greater than or equal to a threshold value.

[0020] This makes it possible to accurately detect failure of the increase process and lower the processing rate.

[0021] In the communication device, it is preferable that the lowering process is a process of adjusting all of the processing rates related to the data transmitted by the communication unit to the lowest processing rate among all the processing rates.

[0022] The descending process can be performed using simple and reasonable values. In particular, when all the processing rates are uniformly high, the initial processing can be performed without significantly lowering the processing rates.

[0023] According to a second aspect of the present invention, there is provided a communication program as follows. That is, the communication program causes a communication device forming a communication network together with a plurality of other communication devices to execute the following steps. The communication program includes a generation step, a communication step, a decrease step, a determination step, and an increase step. The generation step generates data to be transmitted to the other communication devices. The communication step includes a process of transmitting the data generated in the generation step to any one or more other communication devices among the other communication devices, and a process of receiving from each of the other communication devices a processing rate, which is the amount of processing per unit time when the other communication devices process data. The decrease step performs a decrease process for adjusting the rate of the data transmitted in the communication step to be lowered to each of the other communication devices so that a difference in the processing rate in each of the other communication devices falls within a threshold value. In the determining step, it is determined whether a first start condition that the descending process for the data transmitted in the communicating step has been completed and a second start condition that the descending process for the data transmitted by the other communication device has been completed are satisfied. In the increasing step, when it is determined that the first start condition and the second start condition are satisfied, the transmission rate of the data transmitted to each of the other communication devices is uniformly increased.

[0024] According to a third aspect of the present invention, the following communication method is provided. That is, in the communication method, a communication device communicates with a plurality of other communication devices via a communication network. The communication method includes a generation step, a communication step, a decrease step, a determination step, and an increase step. In the generation step, data to be transmitted to the other communication devices is generated. In the communication step, a process of transmitting the data generated in the generation step to an arbitrary other communication device among the other communication devices, and a process of receiving from each of the other communication devices a processing rate, which is a processing amount per unit time when the other communication device processes data. In the decrease step, a decrease process is performed to adjust the rate of the data to be transmitted to each of the other communication devices lower so that a difference in the processing rate of each of the other communication devices falls within a threshold value with respect to the data transmitted in the communication step. In the determination step, a first start condition that the decrease process for the data transmitted in the communication step has been completed and a second start condition that the decrease process for the data transmitted by the other communication devices has been completed are determined to be satisfied. In the increasing step, when it is determined that the first start condition and the second start condition are satisfied, the transmission rates of the data transmitted to each of the partner communication devices are increased uniformly. [Brief description of the drawings]

[0025] [Figure 1] 1 is a block diagram of a communication system including a communication device according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a network diagram showing a network configuration of an embodiment of the present invention. [Diagram 3] FIG. 3 is a partial network diagram in which the network shown in FIG. 2 is divided according to the source. [Figure 4] 1 is a sequence diagram showing data transmission and receiving processing rate feedback. [Diagram 5] 11 is a flowchart showing a process for changing a processing rate. [Figure 6] State 1 to State 3 processing rate table. [Figure 7] Treatment rate table for states 4 to 6. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] Next, an embodiment of the present invention will be described with reference to the drawings. First, an overview of a communication system 1 will be described with reference to FIG.

[0027] The communication system 1 is installed in a facility such as a factory, a parking lot, or an office. The communication system 1 is composed of a plurality of communication devices, and the communication devices communicate with each other to construct a communication network. The communication system 1 of this embodiment includes a first communication device 10, a second communication device 20, a third communication device 30, a fourth communication device 40, and a distribution device 5. Note that the distribution device 5 is not an essential component and can be omitted.

[0028] The first communication device 10, the second communication device 20, the third communication device 30, and the fourth communication device 40 have substantially the same configuration. Therefore, the first communication device 10 will be described below as a representative. The first communication device 10, the second communication device 20, the third communication device 30, and the fourth communication device 40 may be collectively referred to simply as "communication devices", and the second communication device 20, the third communication device 30, and the fourth communication device 40 may be collectively referred to as "other communication devices". In addition, when focusing on a specific communication device (for example, the first communication device 10), a device to which the specific communication device transmits data may be referred to as a "partner communication device".

[0029] The first communication device 10 of this embodiment is a wireless repeater, and receives data (e.g., video data or image data) from a device (e.g., a camera or a PC) connected by wire or wirelessly. The first communication device 10 transmits the received data to the distribution device 5 or one or more other communication devices by wireless communication. Note that the first communication device 10 is not limited to a wireless repeater, and may be a repeater that communicates only by wired communication. For wireless communication, a communication standard such as IEEE802.11 that is generally used in wireless LAN communication can be used. For wired communication, a communication standard such as IEEE802.3 that is generally used in wired LAN communication can be used.

[0030] As shown in FIG. 1, the first communication device 10 includes a communication unit 11, a control unit 12, and a storage unit 13. The communication unit 11 is specifically a communication module, and can communicate with devices, communication devices, and a distribution device 5. The control unit 12 is a calculation device such as a CPU, and performs communication-related processing and data-related processing. The control unit 12 generates data to be transmitted to other communication devices based on data received from a device, for example. The storage unit 13 is a volatile storage device that can be accessed at high speed, such as a RAM (Random Access Memory), and stores data to be transmitted to other communication devices, data received from other communication devices, programs for performing processing described later, a processing rate table described later, and the like. Note that the storage unit 13 may be configured with a non-volatile storage device such as an HDD, SSD, or flash memory in a usage environment that does not require high-speed access performance such as low-latency communication.

[0031] The distribution device 5 functions as a base station of the communication network of the communication system 1, and has a routing function and a bandwidth adjustment function. Communication between communication devices is performed via the distribution device 5. In the following, in order to simplify the explanation, the phrase "via the distribution device 5" may be omitted when explaining communication between communication devices. The routing function is a function that selects an appropriate route according to the destination of a packet and transfers the packet according to that route. The bandwidth adjustment function is a process that reduces the amount of data exchanged between communication devices according to the load on the communication network.

[0032] Next, the purpose of the communication system 1 of this embodiment will be described. In the communication system 1, when a communication device performs relay communication, data may be adjusted. For example, when video data is communicated, a process of adjusting the resolution or frame rate may be performed to reduce the amount of data. In addition, in the case of image data, the resolution may be adjusted, and in the case of time series data, the sampling rate may be adjusted. This type of adjustment is performed according to the size of the bandwidth available in the communication network and the processing capacity of the communication device. This type of adjustment changes the amount of data processed or transmitted per unit time (hereinafter, the rate).

[0033] When multiple devices (for example, a PC connected to the second communication device 20 and a PC connected to the third communication device 30) receive and refer to the same or the same type of data, it is preferable that the rates of these data are similar. Furthermore, it is preferable that the data rate is high. In consideration of the above, the communication system 1 of this embodiment aims to make the rate of data exchanged over the communication network uniform and high.

[0034] However, as the number of communication devices increases, the network configuration becomes more complex, making it difficult to handle them collectively, and the process of equalizing the data rate becomes cumbersome. Therefore, in this embodiment, the network is divided by the following method, and the rate is equalized for each divided network (sub-network).

[0035] Specifically, in this embodiment, an example is considered in which a first communication device 10, a second communication device 20, a third communication device 30, and a fourth communication device 40 communicate through the network shown in Fig. 2. That is, the first communication device 10 transmits data to the second communication device 20 and the third communication device 30, the second communication device 20 transmits data to the third communication device 30, the third communication device 30 transmits data to the second communication device 20 and the fourth communication device 40, and the fourth communication device 40 transmits data to the first communication device 10 and the second communication device 20. The network shown in Fig. 2 is an example, and the technology of this embodiment is applicable to networks of any connection form.

[0036] The network shown in FIG. 2 can be divided into a plurality of partial networks as shown in FIG. 3. FIG. 3 is a diagram in which the network in FIG. 2 is divided into four partial networks according to the communication device of the data transmission source. In FIG. 3, from the top, a partial network of the first communication device 10 as the transmission source, a partial network of the second communication device 20 as the transmission source, a partial network of the third communication device 30 as the transmission source, and a partial network of the fourth communication device 40 as the transmission source are shown. The plurality of partial networks shown in FIG. 3 are equivalent to the network shown in FIG. 2. In addition, since the communication devices of the data transmission source are different in each partial network shown in FIG. 3, the networks do not interfere with each other. Therefore, in this embodiment, the rate of the entire network is equalized by equalizing the rate for each partial network.

[0037] In this embodiment, the processing rate is equalized. The processing rate is the amount of data received by a communication device and processed by the communication device per unit time. The unit of the processing rate is, for example, Mbps. The processing rate is correlated with the rate of data received by the communication device, and also depends on the processing performance of the communication device. The processing rate is also correlated with the rate of data transferred by the communication device to another communication device or device. Therefore, by equalizing the processing rate for each partial network, the above-mentioned object can be expected to be achieved.

[0038] In this embodiment, each communication device stores the processing rate when processing data, and feeds back the processing rate to the source communication device. A specific description will be given below with reference to the sequence diagram in FIG. 4. The processing order in the sequence diagram in FIG. 4 is an example. Moreover, data transmitted by the nth communication device is referred to as data n (n=1, 2, 3, 4). Moreover, the processing rate when the nth communication device transmits and the mth communication device processes is referred to as Wnm (m=1, 2, 3, 4).

[0039] As shown in Fig. 4, the first communication device 10 generates data 1 and transmits the data 1 to the second communication device 20. The second communication device 20 processes the data 1 and stores the processing rate (W12) in a storage unit. Similarly, the first communication device 10 transmits the data 1 to the third communication device 30, and the third communication device 30 stores the processing rate (W13) in a storage unit. Similar processing is performed according to the flow of communication shown in Fig. 2 or Fig. 3. As a result, each communication device stores the processing rate of the data it has processed.

[0040] Next, the second communication device 20 transmits the processing rate to the first communication device 10 as feedback for data 1. At this time, the second communication device 20 transmits not only the processing rate (W12) of data 1 but also the processing rates (W32, W42) of each piece of data transmitted from the other communication devices to the first communication device 10. The first communication device 10 stores the received processing rates (W12, W32, 42) in a processing rate table in the storage unit 13. This allows the first communication device 10 to grasp not only the processing rate of data 1 transmitted by itself, but also the processing rates in the second communication device 20 of data transmitted by the other communication devices.

[0041] In other words, the processing rate that the first communication device (communication device) 10 receives from the second communication device (first partner communication device) 20 includes the processing rate at which the second communication device 20 processes data 1 transmitted by the first communication device 10, and the processing rate at which the second communication device 20 processes data 3 and 4 transmitted by the third communication device 30 and the fourth communication device 40 (second partner communication device).

[0042] Similar processing is performed for the transmitted data 1 to 4. Note that the transmission of the processing rate is a feedback of the data 1 to 4, and is not transmitted to communication devices to which the data 1 to 4 have not been transmitted. For example, the first communication device 10 does not transmit data 1 to the fourth communication device 40 (in other words, there is no communication path between the first communication device 10 and the fourth communication device 40). Therefore, the first communication device 10 does not receive the processing rate directly from the fourth communication device 40. This makes it possible to prevent the bandwidth and processing capacity from being excessively allocated to collecting the processing rate. Note that the processing in this embodiment is an example, and the processing rate may also be transmitted to communication devices to which the data 1 to 4 have not been transmitted.

[0043] By carrying out the above processing, each communication device acquires and stores the processing rate. As a result, the processing rate table shown in state 1 of FIG. 6 is obtained. The processing rate table shown in FIG. 6 is generated based on feedback of the processing rate received by the first communication device 10, and not only the processing rate of the communication device that received the data 1 transmitted by the device itself, but also the processing rate for the data transmitted by other communication devices is received and described as described above. The rows of the processing rate table indicate the transmitting communication device (in other words, the communication device that generated and transmitted the data), and the columns of the processing rate table indicate the receiving communication device (in other words, the communication device that processed the data). Since the processing rate table is generated based on the received feedback, the processing rate (W41) created by the device itself in processing the data received from the fourth communication device 40 and the communication device for which no communication path exists are not included in the processing rate table, and the processing rate is stored as "0". However, the processing rate (W41) created by the device itself may be included in the processing rate table.

[0044] In addition, the processing rate may vary over time. Therefore, each communication device acquires and stores the processing rate at regular intervals or at a predetermined timing. The processing rate table is created in each communication device based on the processing rate shared by each of the other communication devices, and is stored in each storage unit 13.

[0045] Next, the processing performed by the first communication device 10, the second communication device 20, the third communication device 30, and the fourth communication device 40 will be described using the processing rate. Each communication device executes the flowchart shown in FIG. 5. A communication program for executing this flowchart is stored in the storage unit 13, and the flowchart is executed by executing the communication program, thereby realizing the communication method of this embodiment. Below, the processing performed by the first communication device 10 (specifically, the control unit 12) will be described as a representative. Therefore, the first communication device 10 corresponds to the "communication device" of the present invention, and the second communication device 20 and the third communication device 30, which are the destinations of data, correspond to the "other communication device".

[0046] After acquiring the processing rates, the first communication device 10 judges whether or not the multiple processing rates for data 1 transmitted by its own device (multiple processing rates when its own device is the sender) match each other (S101). Note that although "match" is used here simply, in reality it means that the difference between the multiple processing rates is equal to or less than a threshold. In the processing rate table for state 1 in FIG. 6, the processing rates enclosed by the dashed line correspond to the "multiple processing rates for data 1 transmitted by its own device". Note that a "0" entered in the processing rate table indicates that there is no processing rate, and therefore does not need to be used in this judgment.

[0047] Normally, since each device performs processing independently without constraints, there is a high possibility that the "multiple processing rates for data 1 transmitted by the first communication device 10" do not match. If these processing rates do not match, the first communication device 10 performs a lowering process (S102). The lowering process is a process of adjusting the transmission rate of data 1 transmitted by the first communication device 10 to be lower so that the difference between these processing rates falls within a threshold value described later (with the goal of falling within the threshold value). For example, if the processing rate (W13) of the third communication device 30 is higher than the processing rate (W12) of the second communication device 20, the first communication device 10 lowers the transmission rate of data 1 transmitted to the third communication device 30 so that the processing rate (W13) becomes lower. In other words, the first communication device 10 lowers and adjusts the transmission rate of data 1 transmitted by the first communication device 10 so that the other processing rates (W13) match the lowest processing rate (W12). It should be noted that this decrease process is merely an example, and the first communication device 10 may decrease all of the processing rates so as to match a predetermined processing rate.

[0048] As a result of the above-mentioned decrease process, the processing rate of the receiving communication device decreases, and the first communication device 10 obtains this decreased processing rate as feedback from the receiving communication device. In the following, the processing rate after the decrease process for data n transmitted by the nth communication device is indicated as w1. State 2 in FIG. 6 illustrates a state in which the processing rates of all data transmitted by the first communication device 10 match the processing rate (w1). It should be noted that there is no need to adjust the processing rate (w1) of data 1 transmitted by the first communication device 10 to match the processing rates (w2, w3) of data transmitted by other communication devices.

[0049] In addition, in the judgment of step S101, if the difference in the processing rate of the data transmitted by the own device among the communication devices on the receiving side is equal to or less than a threshold value, or if there is only one applicable processing rate, the lowering process is skipped. Note that if there is only one applicable processing rate, there is a possibility that the processing will continue at a high processing rate, so in order to avoid this, a process of lowering the processing rate to a predetermined value may be performed.

[0050] Next, the first communication device 10 judges whether the first start condition and the second start condition are satisfied (S103). The first start condition is that the descending process of the own device (the first communication device 10) is completed. In other words, completion is when multiple processing rates related to data 1 transmitted by the own device match, or the difference between the processing rates is equal to or less than a threshold. Becoming equal to or less than the threshold indicates that a state below the threshold is maintained for a predetermined time (the same applies to other thresholds). The first start condition can be judged by comparing the processing rates received as feedback.

[0051] The second start condition is that the process of lowering the processing rate of data originating from a communication device other than the own device (specifically, the second communication device 20, the third communication device 30, and the fourth communication device 40) is completed. In other words, the processing rates for the data 2 transmitted by the second communication device 20 match, or the difference between the processing rates is equal to or less than a threshold, and the same condition is satisfied for the third communication device 30 and the fourth communication device 40. Specifically, the numerical values ​​of the processing rates surrounded by the dashed lines shown in the processing rate table of state 2 in FIG. 6 match, etc. Also, the processing rate table of state 3 in FIG. 6 shows a state in which the process of lowering the other communication devices is completed. Note that, when there is only one applicable processing rate, there is a possibility that the processing will continue at a high processing rate, so in order to avoid this, a process of lowering the processing rate to a predetermined value may be performed.

[0052] In addition, after the lowering process is performed in the other communication device, the later-described increasing process may be performed prior to the first communication device 10. When the increasing process is started, the processing rate increases. Therefore, the first communication device 10 may determine that the second start condition is satisfied when all the processing rates in the other communication device become higher compared to the immediately preceding processing rate.

[0053] When the first communication device 10 determines that the first start condition and the second start condition are satisfied, the first communication device 10 performs an increase process (first stage of the increase process) to improve communication efficiency (S104). The increase process is a process in which the transmission rate of the data 1 transmitted by the first communication device 10 is uniformly increased, and the processing rate at which the other communication devices process the data 1 is uniformly increased. Specifically, the first communication device 10 multiplies the transmission rate of the data 1 by a coefficient α (1<α). As a result, as shown in the processing rate table of state 4 in FIG. 7, the processing rate is expected to be increased by α times. Note that if the processing rate is suddenly increased, the upper limit of the band may be reached, so it is preferable to increase the processing rate gradually. Therefore, it is preferable that the coefficient α is a value that is greater than 1 and close to 1, for example, a value that satisfies the condition of 1.5 or less, 1.3 or less, or 1.1 or less. The coefficient α is set to an appropriate value in advance and stored in each communication device.

[0054] The increase process by multiplying the coefficient α is just one example. Instead of this increase process, a process of gradually increasing the transmission rate may be performed so as to reach a predetermined processing rate. However, such a process that changes every moment (dynamic process) requires the communication devices to transmit and receive metadata, for example, between each communication device, which would hinder the purpose of reducing the processing and communication load, so a constant that does not change by time is preferable.

[0055] Next, the first communication device 10 judges whether or not the third start condition and the fourth start condition are satisfied (S105). The third start condition is that the increase process of the own device (the first communication device 10) is completed. In other words, the multiple processing rates related to the data 1 transmitted by the own device are increased by a factor of α, and the respective processing rates are the same or the difference between the processing rates is equal to or less than a threshold. The judgment of the third start condition can be performed by comparing the processing rates received as feedback.

[0056] The fourth start condition is that the process of increasing the processing rate of data sent from a communication device other than the own device (specifically, the second communication device 20, the third communication device 30, and the fourth communication device 40) has been completed. In other words, the processing rate for the data 2 sent by the second communication device 20 has increased by a factor of α, and the respective processing rates are the same or the difference between the processing rates is equal to or less than a threshold, and the same condition is also satisfied for the third communication device 30 and the fourth communication device 40.

[0057] When the first communication device 10 determines that the third start condition and the fourth start condition are satisfied (Yes in step S105), the process returns to step S104 and performs the increase process (second stage of the increase process). Specifically, the first communication device 10 further multiplies the transmission rate of data 1 by the coefficient α. That is, as shown in the processing rate table of state 6, the processing rate immediately after the decrease process is multiplied by the square of α.

[0058] In this way, by performing the increase process in multiple stages, it is possible to prevent the processing rate from increasing too rapidly. By repeating steps S104 and S105, it is possible to increase the processing rate while maintaining the processing rate in a uniform state.

[0059] During the increase process, the first communication device 10 judges whether the increase process has failed (S106). For example, when some processing rates are significantly decreased (the decrease rate of the processing rate is equal to or greater than the threshold), or when the difference between the processing rates is equal to or greater than the threshold again (that is, when the processing rates are not consistent for a predetermined time, or when the processing rates are not consistent even after the increase process is repeated a certain number of times), the first communication device 10 judges that the increase process has failed. Causes of the increase process failure include poor communication, a transmission rate being set too high, the processing rate reaching a predetermined upper limit, and the distribution device 5 adjusting the bandwidth. When the first communication device 10 judges that the increase process has failed, it performs the decrease process again (S102). In this case, the same judgment is performed for the other communication devices, so that all communication devices start over from the decrease process. On the other hand, when the first communication device 10 judges that the increase process has not failed, it again judges whether the third start condition and the fourth start condition are satisfied (S105). In the flow shown in Fig. 5, each communication device transmits data while alternating between increasing and decreasing the processing rate to maintain equilibrium. However, although not shown in Fig. 5, it is also possible for each communication device to eventually exit this loop in some situation and operate at a fixed transmission rate.

[0060] In this manner, in this embodiment, the network is divided for each communication device that is a source, and the processing rate is equalized for each divided partial network. This makes it possible to realize a uniform processing rate with a realistically executable processing amount.

[0061] As described above, the first communication device 10 of this embodiment forms a communication network together with a plurality of other communication devices (the second communication device 20, the third communication device 30, the fourth communication device 40, the same below). The first communication device 10 includes a control unit 12 and a communication unit 11. The control unit 12 generates data 1 to be transmitted to an arbitrary other communication device (the second communication device 20, the third communication device 30, the same below) among the other communication devices (generation step, generation process). The communication unit 11 performs a process of transmitting the data 1 generated by the control unit 12 to the other communication device, and a process of receiving from each of the other communication devices a processing rate, which is the amount of processing per unit time when the other communication device processes the data 1 (communication step, communication process). The control unit 12 performs a descending process, a determining process, and an ascending process. In the descending process, the transmission rate of data 1 transmitted to each of the other communication devices is adjusted downward so that the difference in the processing rate of each of the other communication devices for data 1 transmitted by communication unit 11 falls within a threshold (descending step, descending process). In the determining process, it is determined whether or not a first start condition that the descending process for data 1 transmitted by communication unit 11 has been completed and a second start condition that the descending process for data 2, 3, and 4 transmitted by the other communication devices has been completed are satisfied (determining step, determining process). In the increasing process, when it is determined that the first start condition and the second start condition are satisfied, the transmission rate of data 1 transmitted to each of the other communication devices is uniformly increased (increasing step, increasing process).

[0062] The transmission rate is lowered once by the descending process to make the processing rate uniform, and then the transmission rate is increased uniformly by the ascending process, so that the processing rate can be made uniform and increased in speed. In addition, since multiple transmission rates are changed at once, the amount of processing can be reduced compared to when the transmission rate is changed for each individual communication path.

[0063] In the first communication device 10 of this embodiment, the processing rate received by the communication unit 11 from the second communication device 20 includes not only the processing rate (W12) and the processing rate (W13) at which the second communication device 20 processes data 1 generated by the control unit 12 of the first communication device 10 and transmitted by the communication unit 11, but also the processing rate (W32) at which the second communication device 20 processes data 3 generated and transmitted by the third communication device 30.

[0064] This allows the first communication device 10 to acquire all the necessary information at once.

[0065] In the first communication device 10 of this embodiment, the control unit 12 determines that the second start condition is satisfied when the processing rate for data transmitted from each of the other communication devices, when the transmitting partner communication device is the same, becomes higher than the immediately preceding processing rate.

[0066] This allows the ascending process to be started even if another communication device has already started the ascending process.

[0067] In the first communication device 10 of this embodiment, the increase process includes at least a first stage and a second stage. After performing the first stage of the increase process and determining that the first stage is completed, the control unit 12 performs the second stage of the increase process.

[0068] As a result, the processing rate is further increased after it has been uniformized, so that the processing rate is less likely to become non-uniform.

[0069] In the first communication device 10 of this embodiment, the first stage of the increase process is a process of increasing the processing rate to a value obtained by multiplying the processing rate after the decrease process (for data n transmitted by the nth communication device) by the coefficient α. The second stage of the increase process is a process of increasing the processing rate to a value obtained by multiplying the processing rate by the square of the coefficient α. If the increase process is successful after this, the process of multiplying by α may be continued.

[0070] The increase process can be multi-staged with simple processing. Also, the number of stages to which the increase process has progressed can be easily detected.

[0071] In the first communication device 10 of this embodiment, if the control unit 12 determines that the ascent process has failed after performing the ascent process, it performs the descent process again.

[0072] This allows the processing rate to be lowered if it is increased too much.

[0073] In the first communication device 10 of this embodiment, if the control unit 12 determines that, after performing the upward process, the rate of decrease in the processing rate is greater than or equal to a threshold value, or the difference in the processing rates is greater than or equal to a threshold value, then the control unit 12 performs the downward process again.

[0074] This makes it possible to accurately detect failure of the increase process and lower the processing rate.

[0075] In the first communication device 10 of this embodiment, the descending process is a process of adjusting all processing rates related to the data 1 transmitted by the communication unit 11 to the lowest processing rate among all the processing rates.

[0076] This allows the descending process to be performed using simple and reasonable values. In particular, when all the processing rates are uniformly high, the initial process can be performed without significantly lowering the processing rate.

[0077] Although the preferred embodiment of the present invention has been described above, the above configuration can be modified, for example, as follows.

[0078] In the above embodiment, the start timing of the first increase process is determined based on the processing rate included in the feedback. Alternatively, the second start condition may be determined based on whether or not the completion of the decrease process has been notified from another communication device, and the start timing of the first increase process may be determined. Also, the fourth start condition may be determined based on whether or not the completion of the previous increase process has been notified from another communication device, and the start timing of the next increase process may be determined.

[0079] The flowcharts shown in the above embodiments are merely examples, and some processes may be omitted, some processes may be changed, or new processes may be added. For example, the transmission rate may be increased continuously (gradually) without dividing the increase process into multiple stages. [Explanation of symbols]

[0080] 1. Communication Systems 10 First communication device (communication device) 11 Communications Department 12 Control section 13 Storage section 20 Second communication device (partner communication device) 30 Third communication device (partner communication device) 40 Fourth communication device

Claims

1. A communication device forming a communication network together with a plurality of other communication devices, A control unit that generates data to be transmitted to the other communication device; a communication unit that performs a process of transmitting the data generated by the control unit to any one or more other communication devices among the other communication devices, and a process of receiving a processing rate, which is a processing amount per unit time when the other communication device processes the data, from each of the other communication devices; Equipped with The control unit is a decrease process of decreasing a transmission rate of the data transmitted by the communication unit to each of the other communication devices so that a difference in the processing rate of each of the other communication devices falls within a threshold value; a determination process for determining whether a first start condition that the descent process for the data transmitted by the communication unit has been completed and a second start condition that the descent process for the data transmitted by the other communication device have been completed are satisfied; an increase process of uniformly increasing a transmission rate of the data transmitted to each of the partner communication devices when it is determined that the first start condition and the second start condition are satisfied; A communication device comprising:

2. 2. The communication device according to claim 1, The processing rate that the communication unit receives from the other communication device includes: the processing rate at which the other communication device processes the data generated by the control unit and transmitted by the communication unit; and the processing rate at which the other communication device processes data generated by the other communication device and transmitted to the other communication device; and A communication device comprising:

3. 2. The communication device according to claim 1, A communication device characterized in that the control unit determines that the second start condition is satisfied when the processing rate for the data transmitted by the other communication device and, when the transmitting party is the same communication device, the processing rate for the data transmitted from each of the other communication devices is higher than the immediately preceding processing rate.

4. 2. The communication device according to claim 1, The raising process includes at least a first stage and a second stage, A communication device characterized in that the control unit performs the second stage of the increase processing after performing the first stage of the increase processing and determining that the first stage has been completed.

5. 5. The communication device according to claim 4, the first stage of the increase process is a process of increasing the processing rate to a value obtained by multiplying the processing rate by a coefficient, A communication device, characterized in that the second stage of the increase process is a process of increasing the processing rate to a value obtained by multiplying the processing rate by a square of a coefficient.

6. 2. The communication device according to claim 1, The communication device according to claim 1, wherein the control unit, after performing the increase process, when it determines that the increase process has failed, performs the decrease process again.

7. 2. The communication device according to claim 1, A communication device characterized in that the control unit performs the decrease process again when it determines that after performing the increase process, the rate of decrease of the processing rate is greater than or equal to a threshold value, or the difference in the processing rates is greater than or equal to a threshold value.

8. 2. The communication device according to claim 1, The communication device, wherein the lowering process is a process of adjusting all of the processing rates related to the data transmitted by the communication unit to the lowest processing rate among all of the processing rates.

9. A communication device that forms a communication network with a plurality of other communication devices, A generating step of generating data to be transmitted to the other communication device; a communication step including a process of transmitting the data generated in the generation step to any one or more other communication devices among the other communication devices, and a process of receiving a processing rate, which is a processing amount per unit time when the other communication device processes the data, from each of the other communication devices; a descending step of performing a descending process of adjusting the rate of the data transmitted in the communication step to a lower rate so that a difference in the processing rate of each of the other communication devices falls within a threshold value; a determination step of determining whether a first start condition that the descent process for the data transmitted in the communication step has been completed and a second start condition that the descent process for the data transmitted by the other communication device has been completed are satisfied; an increasing step of uniformly increasing a transmission rate of the data transmitted to each of the partner communication devices when it is determined that the first start condition and the second start condition are satisfied; A communication program characterized by causing the program to execute the above steps.

10. 1. A method of communication in which a communication device communicates with a plurality of other communication devices over a communication network, comprising: a generating step of generating data to be transmitted to the other communication device; a communication process including a process of transmitting the data generated in the generation process to an arbitrary other communication device among the other communication devices, and a process of receiving a processing rate, which is a processing amount per unit time when processing the data, from each of the other communication devices; a descending process for performing a descending process for adjusting the rate of the data transmitted in the communication process to be transmitted to each of the other communication devices so that a difference in the processing rate of each of the other communication devices falls within a threshold value; a determination step of determining whether a first start condition that the descent process for the data transmitted in the communication step has been completed and a second start condition that the descent process for the data transmitted by the other communication device has been completed are satisfied; an increasing step of uniformly increasing a transmission rate of the data transmitted to each of the partner communication devices when it is determined that the first start condition and the second start condition are satisfied; A communication method comprising:

Images