JP2002125002A - Data transmitter, data receiver, method for transmitting data, and method for receiving data - Google Patents

Abstract

PROBLEM TO BE SOLVED: To set the data transmission rate of a transmission side computer without causing overflow of the buffer in a receiving side computer. SOLUTION: The data transmission rate regulating section 11 of a transmission side computer 1 begins data transmission at a data transmitting section 12 starting from data having a lowest transmission rate and increases the data transmission rate stepwise until a message designating deceleration is delivered from the data transmission rate setting section 23 of a receiving side computer 2 while recording the data transmission rate at each stage. In the receiving side computer 2, the receiving buffer monitoring section 21 monitors data accumulation at a receiving buffer section 20 and when the accumulated data reaches a specified level, the data transmission rate setting section 23 transmits the message designating deceleration to the transmission side computer 1 where the data transmission rate regulating section 11 regulates the data transmission rate to a one step lower level based on the record of data transmission rate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a transmission flow control method when a plurality of data transmission devices transmit and receive data while maintaining synchronization.

[0002]

2. Description of the Related Art For example, the transmission flow control method disclosed in Japanese Patent Application Laid-Open No. 05-75666 is characterized in that a reception data processing speed of a receiving device is obtained and a transmission data transmission speed is adjusted based on the obtained reception data processing speed. Is described.

FIG. 24 shows a conventional transmission flow control method.
This will be described with reference to FIG. The transmission-side computer transmits data to the reception-side computer at a transmission speed such that “transmission speed> reception data processing speed”. The receiving computer calculates the data processing speed from the amount of data accumulated in a certain time,
The calculated value is transmitted to the transmitting computer. The sending computer is
The data processing speed transmitted by the receiving computer is received, the transmission speed is changed to the value, and the data transmission is continued.

[0004]

The transmission flow control system in the prior art is configured as described above, and has the following problems.

In the transmission flow control method in the prior art, at the start of transmission, transmission starts at the full transmission speed regardless of the free space in the buffer of the receiving device. Overflow of the reception buffer may occur.

Further, the transmission flow control method according to the prior art does not assume that a plurality of computers transmit data to a common reception buffer, and the plurality of computers together at the transmission speed are full in the method according to the prior art. If the transmission is started at the transmission speed, the reception buffer may overflow before the transmission speed is determined.

According to the present invention, data transmission is started at the minimum transmission rate, and the data transmission rate is increased until the processing speed of the reception buffer and the data transmission rate of the transmitting computer become the same. The purpose is to prevent a buffer overflow from occurring during.

Another object of the present invention is to further reduce the amount of memory required for the receiving buffer by always making the data transmission speed lower than the data processing speed of the receiving device.

Another object of the present invention is to receive a message without causing a buffer overflow even when a plurality of transmitting devices transmit data to a common receiving buffer.

[0010]

A data transmitting apparatus according to the present invention is a data transmitting apparatus for transmitting data by adjusting a data transmission speed by communicating with a data receiving apparatus. An instruction message receiving unit that receives an instruction message instructing the adjustment of the data transmission speed, and, until the instruction message is received by the instruction message receiving unit, the data transmission speed is increased, and the instruction message is received. A data transmission speed adjusting unit for adjusting the data transmission speed according to the instruction message.

The instruction message receiving unit receives, as the instruction message, a deceleration instruction message for instructing a reduction in the data transmission speed, and the data transmission speed adjusting unit transmits the deceleration instruction message by the instruction message receiving unit. Until it is received, the data transmission speed is increased stepwise, and the data transmission speed in each of the ascending stages is recorded, and when the instruction message receiving unit receives the deceleration instruction message, The data transmission speed is switched to a lower data transmission speed than the data transmission speed when the deceleration instruction message is received, based on the recording of the data transmission speed.

The instruction message receiving unit receives, as the instruction message, an increase inhibition instruction message for inhibiting the increase of the data transmission speed, and the data transmission speed adjusting unit controls the increase inhibition instruction by the instruction message receiving unit. It is characterized by maintaining a data transmission rate when a message is received.

[0013] The instruction message receiving unit receives, as the instruction message, an increase instruction message instructing an increase in the data transmission rate, and the data transmission rate adjusting unit transmits the increase instruction message by the instruction message receiving unit. After the reception, the data transmission speed is increased until the deceleration instruction message is received.

[0014] The data transmitting apparatus has a request transmitting section for transmitting a rise permission request for requesting permission to increase the data transmission rate, and the instruction message receiving section is configured to transmit the increase message transmitted by the request transmitting section. As the ascent permission for the permission request, the ascending instruction message is received.

[0015] A data receiving apparatus according to the present invention receives data from a data transmitting apparatus that transmits data while increasing a data transmission speed step by step, and within the allowable range of its own received data processing capacity, A data receiving device for setting the data transmission speed of the data receiving device, receiving data transmitted from the data transmitting device, storing the received data received, the received data stored in the receiving buffer unit A reception data processing unit that performs reception processing of the reception data; a reception buffer monitoring unit that monitors the amount of the reception data stored in the reception buffer unit; and a storage of the reception data based on a monitoring result by the reception buffer monitoring unit. Until the amount reaches a predetermined level, the data transmission device gradually increases the data transmission speed, and If it is determined that the storage amount has reached a predetermined level, it is determined that the data transmission speed has exceeded the allowable range of the reception data processing capacity of the reception data processing unit, and the data transmission device A data transmission speed setting unit for instructing reduction of the transmission speed.

[0016] The data transmission speed setting unit is configured to step the data transmission speed by the data transmission device until the accumulated amount of the received data reaches a first level based on the monitoring result by the reception buffer monitoring unit. When the storage amount of the reception data reaches the first level, the data transmission device is prohibited from increasing the data transmission speed, and the storage amount of the reception data becomes the second level. When the data transmission speed has reached, it is determined that the data transmission speed has exceeded the allowable range of the reception data processing capacity of the reception data processing unit, and instructing the data transmission device to reduce the data transmission speed. Features.

A data receiving apparatus according to the present invention receives data from a plurality of data transmitting apparatuses and sets a data transmission speed of the plurality of data transmitting apparatuses within an allowable range of its own received data processing capability. A data transmission device for identifying a transmission speed-set device that sets the data transmission speed and a transmission speed-unset device that does not set the data transmission speed among the plurality of data transmission devices. An identification unit for instructing the transmission speed-set device identified by the data transmission device identification unit to reduce the data transmission speed, and performing the reception data processing based on the data transmission speed reduction of the transmission speed-set device. Having a data transmission speed setting unit for distributing a capability to the transmission speed unset device and setting a data transmission speed of the transmission speed unset device. And it features.

The data transmission speed setting unit increases the data transmission speed of the transmission speed non-setting device step by step within the allowable range of the reception data processing capability, and sets the data transmission speed of the transmission speed non-setting device to a predetermined value. Is set.

The data transmission speed setting unit is configured to reduce the data transmission speed for the transmission speed set device based on a ratio between the number of the transmission speed set devices and the total number of the plurality of data transmission devices. It is characterized by indicating a level.

The data transmission device identification section identifies a priority set for each of the plurality of data transmission devices, and the data transmission speed setting section determines a priority set by the data transmission device identification section. In response to this, the transmission speed setting device is instructed on the deceleration level of the data transmission speed.

The data transmission speed setting section prohibits the transmission speed non-setting device from increasing the data transmission speed, and instructs the transmission speed setting device to reduce the data transmission speed. Prohibiting the increase in the data transmission speed for the transmission-rate-unset device is canceled and the data transmission speed of the transmission-rate-unset device is set.

The data transmission speed setting unit instructs the transmission speed setting device to decelerate to a predetermined data transmission speed, and sets the same data transmission speed as the predetermined data transmission speed to the transmission speed unset value. It is characterized in that it is set as a data transmission speed to the setting device.

The data transmission speed setting section is configured to divide a value obtained by dividing a total of the data transmission speeds set for the devices for which the transmission speed is already set by the total number of the plurality of data transmission devices with the predetermined data transmission speed. It is characterized by doing.

The data transmission speed setting unit instructs the transmission speed setting device to increase the data transmission speed, and sets the data of the transmission speed setting device within the allowable range of the reception data processing capability. The transmission rate is increased stepwise, and a new data transmission rate is set for the transmission rate-set device.

[0025] The data receiving apparatus further includes a request receiving unit for receiving an increase permission request for requesting permission to increase the data transmission rate, which is transmitted from the transmission rate-set apparatus. The setting unit permits the transmission rate-set device, which has transmitted the increase request received by the request reception unit, to increase the data transmission speed, and performs the transmission within an allowable range of the reception data processing capability. The data transmission speed of the device whose speed has been set is gradually increased, and a new data transmission speed is set for the device whose transmission speed has been set.

A data transmission method according to the present invention is a data transmission method for transmitting data by adjusting a data transmission speed by communicating with a data reception method, wherein the data transmission speed is adjusted by the data reception method. An instruction message receiving step of receiving an instruction message instructing
A data transmission rate adjustment that increases the data transmission rate until the instruction message is received by the instruction message receiving step, and adjusts the data transmission rate according to the instruction message when the instruction message is received. And a step.

The instruction message receiving step receives, as the instruction message, a deceleration instruction message for instructing deceleration of the data transmission speed, and the data transmission speed adjusting step includes the step of receiving the instruction message, the step of receiving the instruction message. Until it is received, the data transmission speed is stepwise increased, and the data transmission speed in each of the ascending stages is recorded, and when the deceleration instruction message is received by the instruction message receiving step, The data transmission speed is switched to a lower data transmission speed than the data transmission speed when the deceleration instruction message is received, based on the recording of the data transmission speed.

[0028] In the data receiving method according to the present invention, data is received from a data transmitting method in which data is transmitted while the data transmitting speed is increased stepwise, and the data transmitting method is performed within an allowable range of its own received data processing capability. A data receiving method for setting a data transmission speed of the data receiving method, receiving data transmitted by the data transmitting method, and accumulating the received data received; and A reception data processing step of performing a reception data reception process, a reception data accumulation amount monitoring step of monitoring an accumulation amount of the reception data accumulated in the reception data accumulation step, and a monitoring result by the reception data accumulation amount monitoring step. The data transmission method until the storage amount of the received data reaches a predetermined level. The data transmission speed is increased stepwise, and when it is determined that the storage amount of the reception data has reached a predetermined level, the data transmission speed increases the allowable range of the reception data processing capability of the reception data processing step. A data transmission speed setting step of instructing the data transmission method to decelerate the data transmission speed upon determining that the data transmission speed has been exceeded.

A data receiving method according to the present invention receives data from a plurality of data transmission methods and sets a data transmission speed of the plurality of data transmission methods within an allowable range of its own received data processing capability. A data transmission method for identifying a transmission speed setting method that sets the data transmission speed and a transmission speed non-setting method that does not set the data transmission speed among the plurality of data transmission methods. An identification step, and instructing the data transmission rate-set method identified by the data transmission method identification step to reduce the data transmission rate, and performing the reception data processing based on the data transmission rate reduction of the transmission rate-set method. A data transmission speed setting step of distributing the capability to the transmission speed non-setting method and setting a data transmission speed of the transmission speed non-setting method. And having a flop.

[0030]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiment 1 FIG. 1 is a diagram showing a device configuration according to the first embodiment. In the present embodiment, a configuration in which a plurality of computers 1 are connected by a network 6 is adopted. Reference numeral 1 denotes a data transmission side computer (hereinafter, also referred to as a transmission side computer) as a data transmission device, and reference numeral 2 denotes a data reception side computer (hereinafter, also referred to as a reception side computer) which is a data reception device. In FIG. 1, the transmission side computer 1 and the reception side computer 2 are separately illustrated, but they are separated for the sake of simplicity of explanation,
In terms of implementation, one computer can have both functions of the transmitting computer 1 and the receiving computer 2.

Next, the components of the transmitting computer 1 will be described. Reference numeral 10 denotes an instruction message receiving unit that receives an instruction message related to the data transmission speed from the receiving computer 2; 11 denotes a data transmission speed adjustment unit that adjusts the data transmission speed; and 12 transmits data to the data receiving device. It is a data transmission unit. Data transmission speed adjustment unit 11
Records the data transmission speed at the time of data transmission (hereinafter also referred to as data transmission speed), and adjusts the data transmission speed based on the recording of the data transmission speed. In the present embodiment, the data transmission speed is adjusted by adjusting the data transmission time interval during data transmission and the size of data transmitted at one time.

Next, the components of the receiving computer 2 will be described. Reference numeral 20 denotes a reception buffer unit, which is a memory area on a computer for temporarily storing received data. Reference numeral 21 denotes a reception buffer monitoring unit, which has a role of monitoring the amount of data stored in the reception buffer unit 20. Reference numeral 22 denotes a reception data processing unit which has a role of processing data stored in the reception buffer unit 20 when receiving data. Reference numeral 23 denotes a data transmission speed setting unit, which compares the processing capability (processing speed) of the reception data processing unit with the data transmission speed based on the monitoring result of the reception buffer monitoring unit 21, , And an appropriate data transmission speed is set.

It is assumed that the reception buffer unit 20 and the reception buffer monitoring unit 21 each have one connection. For example, FIG. 2 is a diagram illustrating a case where the receiving computer is simultaneously communicating with two computers, the transmitting computer (1) and the transmitting computer (2). In this case, the receiving computer has two connections, that is, a connection with the transmitting computer (1) and a connection with the transmitting computer (2). ) And the receiving buffer unit 20c for the transmitting computer (2).
There are also two reception buffer monitoring units, a reception buffer monitoring unit 21b for the transmission-side computer (1) and a reception buffer monitoring unit 21c for the transmission-side computer (2).

FIGS. 3 and 4 show the operation procedure of the transmitting computer and the receiving computer in the first embodiment, respectively. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

First, the operation procedure of the transmitting computer 1 will be described with reference to FIG. The data transmission rate adjusting unit 11 of the transmission side computer 1 sets the lowest transmission rate (slowest transmission rate) V (step S1). The method of setting the minimum transmission speed V here may be realized by increasing the time interval for transmitting a message, or may be realized by reducing the size of a message transmitted at a time. Then, the data transmission speed adjustment unit 11 determines in step S
1 to the data transmission unit 12 for data transmission at a data transmission rate specified in step 1 (step S
2). The “specified time” described here can be given, for example, by the user, or may be determined by the system. Then, a notification (deceleration instruction message) notifying that “data transmission speed> reception data processing speed” is transmitted from the receiving computer,
It is checked whether or not the instruction message has been received (step S3), and if not, the process proceeds to step S4. In step S4, if the specified time has not elapsed since the start of data transmission at the transmission speed V, steps S2 and S3 are repeated until the specified time elapses. When the elapsed predetermined time, the data transmission speed adjusting section 11 (a V ₂₎ records the transmission speed V and (step S5), and one step raise the value of the transmission rate (step S
6) Return to step S2. The method of increasing the value of the transmission speed in step S6 may be realized by shortening the message transmission interval, or may be realized by increasing the size of a message transmitted at one time. Steps S2 to S6 are repeated until a notification that "data transmission speed> received data processing speed" is received from the receiving computer in step S3.

In step S3, "data transmission speed> received data processing speed" transmitted from the data receiving side computer
If it notification (deceleration instruction message) has been received by the instruction message receiving unit 10 in the data transmission speed adjusting section 11 changes the data transmission rate V, and transmission rate V ₂ which has been recorded (Step S7), data transmission is continued (Step S8). Thus, the transmission speed is determined in step S8. Hereinafter, the state in which the transmission speed is determined is called a steady state.

Next, FIG. 4 shows the operation procedure of the receiving computer. The data receiving computer waits for data to arrive (step S11), and the reception buffer unit 2
When the data reaches 0, the received data processing unit 22 performs data processing (step S12). After the data processing, the reception buffer monitoring unit 21 refers to the reception buffer unit 20 (step S13). If the data sent from the transmission-side computer 1 has already arrived at the reception buffer unit 20,
Since “reception data processing speed <data transmission speed”, the data transmission speed setting unit 23 determines that the data transmission speed has exceeded the allowable range of the reception data processing capability of the reception data processing unit 22, and proceeds to step S15 to perform data transmission. The speed setting unit 23 notifies the data transmission side computer 1 that "reception side data processing speed <data transmission speed" (step S15). Specifically, the data transmission speed setting unit 23 sends a deceleration instruction message. This is done by sending Thereafter, as described above, the transmission-side computer 1 lowers the data transmission speed by one step and transmits the data. Thus, the data transmission speed setting unit 23 sets the data transmission speed of the transmitting computer. Then, in step S16, data arrival is waited, and the received data is processed by the received data processing unit 22. (Step S17). Steps S16 and S17
Repeat as long as data arrives. Steps S16 and S17 are processing when the data transmission side computer 1 is in a steady state.

At step S14, the reception buffer unit 20
On the other hand, if the data transmitted from the data transmitting computer 1 has not yet arrived, the received data processing speed is equal to or greater than the data transmission speed, so that no notification is made to the data transmitting computer 1 and the process proceeds to step S11. Return and wait for the next data to arrive.

Next, the operation according to the present embodiment will be described with reference to FIG. In the example shown in FIG. 5, and starts data transmission at transmission intervals V _1, is changed after the time T has elapsed, the transmission interval V _2. Since the data reception side computer 2 satisfies “data transmission speed ≦ received data processing speed” at the transmission interval V ₁ ,
No data is stored in the buffer. However, after the lapse of time from the start of the transmission T, to become the transmission interval is changed to V ₂ as "data rate> received data processing speed", received upon receiving the data at time T ₁ Data starts to be accumulated in the buffer unit 20. "Data transmission rate> the received data processing speed" on the data receiving side computer time T ₁
Is transmitted to the data transmission side computer (deceleration instruction message is transmitted). When the instruction reaches the time T ₂ to the data transmitting side computer 1, the data transmission side computer 1 performs data transmission at a transmission interval V _1. As a result, no time T ₃ after being data to the receiving buffer unit 20 is accumulated.

The flow control system according to this embodiment has the following effects. In the conventional method, the data transmission side computer starts data transmission at “data transmission speed> reception data processing speed”. Therefore, when the size of the reception buffer unit is small, a buffer overflow occurs before obtaining the data processing speed. There was a possibility. However, in the present embodiment, since the transmission-side computer starts data transmission at a transmission speed lower than the data processing speed, it is possible to eliminate the possibility of overflow, and furthermore, to reduce the reception buffer buffer size smaller than the conventional method. Can perform data communication.

Embodiment 2 Next, a second embodiment will be described. The components constituting the transmitting computer 1 and the receiving computer 2 in the second embodiment are the same as those in the first embodiment, and are shown in FIG. As in the first embodiment, it is assumed that one reception buffer unit 20 and one reception buffer monitoring unit 21 are provided for each connection. The function of each element in the second embodiment is the same as that in the first embodiment.

FIGS. 6 and 7 show the operation procedure of the data transmitting computer and the data receiving computer in the second embodiment, respectively. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

First, FIG. 6 shows an operation procedure of the data transmission side computer 1. The data transmission speed adjusting unit 11 of the data transmission side computer 1 sets the lowest transmission speed V (step S101). Then, the data transmission unit 12
Performs data transmission at a data transmission rate determined in step S101 for a prescribed time (step S10).
2). Then, a notification (increase prohibition instruction message) notifying that “data transmission speed> reception data processing speed” is transmitted from the receiving computer, and it is checked whether or not the instruction message receiving unit has received the notification. If so, the process proceeds to step S104 (step S103).
In step S104, if the specified time has not elapsed since the start of data transmission at the transmission speed V, steps S102 and S103 are repeated until the specified time elapses. When the elapsed predetermined time, the data transmission speed adjusting section 11 (a V ₂₎ records the transmission speed V (step S105), raising the value of the transmission rate (step S10
6) Return to step S102. The method of increasing the value of the transmission speed in step S106 may be realized by shortening the message transmission interval, or may be realized by increasing the size of a message transmitted at one time. Steps S102 to S106 are repeated until a notification that "data transmission speed> received data processing speed" is received from the receiving computer in step S103.

In step S103, when a notification (increase prohibition instruction message) notifying that "data transmission speed> reception data processing speed" has been received from the receiving computer, the transmission speed V is left as it is. Data transmission is continued (step S107) until a request (deceleration instruction message) for "decrease data transmission speed" is received from the receiving computer (step S108). In step S108, when a request (deceleration instruction message) for “decrease the data transmission speed” is received from the receiving computer, the data transmission speed adjustment unit 11 sets the data transmission speed to step S105.
Is changed to the value (V ₂ ) recorded by the data transmission speed adjusting unit 11 (Step S109), and Step S1
At 10, the data transmission is continued. In step S110, a steady state was set.

Next, FIG. 7 shows an operation procedure of the data receiving side computer. The data receiving computer waits for data to arrive from the data transmitting computer (step S121).
The reception data processing unit 22 performs data processing (step S
122). After the data processing, the reception buffer monitoring unit 21
Refers to the reception buffer unit 20 (step S123),
If the data sent from the transmission-side computer has already arrived at the reception buffer unit 20 (first level), the process proceeds to step S125 because “reception data processing speed <data transmission speed”. The unit 23 notifies the data transmission side computer that “reception data processing speed <data transmission speed” (increase prohibition instruction message) (step S125). If the data has not yet arrived at the reception buffer unit 20 in step S124, there is still room in the reception data processing capacity, so steps S121 to S123 are repeated. In step S126, the reception buffer monitoring unit 21 processes the data received by the reception data processing unit 22 while confirming whether the data has been accumulated in the reception buffer unit 20 by a “predetermined amount” (step S127). In step S126, when the data is accumulated in the reception buffer unit 20 by the “predetermined amount” (second level), the data transmission speed setting unit 23 determines that the data transmission speed is lower than the reception data processing capacity of the reception data processing unit 22. The process proceeds to step S128, determining that the data transmission speed has exceeded the allowable range, and the data transmission speed setting unit 23 requests the transmission-side computer to reduce the data transmission speed (specifically, transmits a deceleration instruction message). In the present embodiment, the “predetermined amount” corresponding to the second level may be determined by the system, for example, or determined by the user. Then, the process proceeds to step S122, where the reception data processing unit 22 processes the data. After step S128, the transmitting computer is in a steady state.

Next, the operation according to the present embodiment will be described with reference to FIG. In the example shown in FIG. 8, and starts data transmission at transmission intervals V _1, is changed after a predetermined time T has elapsed, the transmission interval V _2. At the receiving computer, no data is stored in the receiving buffer unit 20 because the data transmission speed ≦ the data processing speed at the transmission interval V ₁ . However, after the lapse of time from the start of the transmission T, to become the transmission interval is changed to V ₂ as "data rate> received data processing speed", received upon receiving the data at time T ₁ Data starts to be accumulated in the buffer unit 20 (first level). At this time, the receiving computer notifies that "data transmission interval> data processing speed". When the instruction reaches the sender computer, the sending computer performs transmission while in transmission interval V _2, the amount accumulated in the buffer is some predetermined amount (M)
When approaching the (second level) (time T ₂ ), the receiving computer instructs the transmitting computer to request to change the transmission speed. Sender computer after instruction receiving, transmitting data at the transmission interval V _1. As a result, there is no possibility that T ₃ and subsequent data to the receiving buffer unit 20 is accumulated.

The flow control system according to this embodiment has the following effects as compared with the first embodiment. By transmitting a large amount of data to the reception buffer unit and storing the data in the reception buffer unit when there is enough free space in the buffer, the transmission process of the transmission-side computer can be completed quickly.

Embodiment 3 Next, a third embodiment will be described. The components constituting the receiving computer 2 according to the third embodiment are as shown in FIG. 9, and in addition to the configuration of the receiving computer shown in FIGS.
have. Further, the reception buffer unit 2 in the present embodiment
0, unlike the first and second embodiments, the reception buffer monitoring unit 21 has only one for each computer regardless of the number of connections. In the third embodiment, the transmission buffer unit 2 of the transmission-side computer 1 and the reception-side computer 2
0, a reception buffer monitoring unit 21, a reception data processing unit 22,
The operations of the data transmission speed setting unit 23 and the network 6 are the same as those of the first embodiment.

Transmitter identification unit 2 in the third embodiment
4 is a computer in which the data transmission speed is already set (it is in a steady state), and a computer in which the data transmission speed is not set (it is not in a steady state). Means for identification. Transmission device identification unit 2
4 is N in the table if the computer N is transmitting in a steady state.
There is a transmission state table 31 in which the 1st entry is 1, if not transmitting, 0, and transmission is being performed, but if it is not in a steady state, -1 is entered. The transmission device identification unit 24 identifies the computer with the transmission speed set and the computer with the transmission speed not set while referring to the transmission state table.

In the present embodiment, the data transmission speed of n transmitting computers that perform transmission in a steady state is reduced,
A method of distributing the reception data processing capability of the reception data processing unit to the transmission-side computer that has newly started communication (not in a steady state) will be described. FIGS. 10 and 11 show operation procedures of the transmitting computer and the receiving computer in the third embodiment, respectively. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

First, FIG. 10 shows an operation procedure of the transmitting computer. The operation procedure until the transmitting computer enters a steady state is the same as that of the first embodiment, and is as shown in FIG. After the stationary state is set in step S201, in step S202, a request from the receiving computer requests that the transmission speed be reduced to n / (n + 1) (n is the number of computers currently transmitting in the steady state). Until a certain time (until a deceleration instruction message is received), data transmission at a preset constant speed is repeated. In step S202,
When the receiving computer requests that the transmission speed be reduced to n / (n + 1) times, the process proceeds to step S203, where the transmission speed is increased to n / (n + 1) times, and in step S204,
Data transmission is performed again in the steady state.

Next, FIG. 11 shows the operation procedure of the receiving computer. In step S221, the process waits for data to arrive from the transmission-side computer. When the data arrives, the transmission device identification unit 24 refers to the transmission state table 31 (step S222), and the transmission side transmits in the current steady state. It is checked whether or not the computer is (step S223). If the computer is in a steady state, step S2
At 24, the reception data processing unit 22 performs data reception processing, and waits for data arrival again (step S221). As a result of the investigation in step S223, if the computer that has transmitted the data is a computer that has newly started transmission (in an unsteady state) (hereinafter referred to as computer A), the process proceeds to step S223.
Proceed to 225. In step S225, the data transmission speed setting unit 23 transmits an instruction to all the computers (assumed to be n) other than the computer A to increase the transmission speed by n / (n + 1) times. After processing the received data (step S226), the process waits for data arrival in step S227. Data arrival (step S227)
Thereafter, the reception data processing unit 22 processes the data (step S228), and proceeds to step S229. Step S2
29, the reception buffer monitoring unit 21
If the data sent from the transmitting computer has already arrived at the receiving buffer unit 20 as a result of referring to, the total amount of transmitted data from all the computers per unit time exceeds the processing capacity of the receiving computer. Therefore, the computer A is notified that "data transmission speed> data processing speed", and waits for data arrival in step S221. After step S230, the message is received in a steady state.

Next, the operation according to the present embodiment will be described with reference to FIG. In Figure 12, the sending computer in FIG. 9 (1) is the transmission interval and V _1, when performing the transmission in the steady state, the transmitting side computer (2) the sender computer when to start sending (1 ), (2), the behavior of the receiving computer. When the transmission side computer (1) is in the middle of performing a data transmission in the transmission interval V _x, the sending computer at time T ₀ (2) starts transmitting, the transmitting side computer (2)
At the time T ₁ when the data transmitted by arrives at the receiving computer,
Data starts to accumulate in the buffer. Therefore, the receiving computer gives the transmitting computer (1) a transmission speed of （(n
/ (N + 1)) to decrease so instructs the sender computer (1) is from above instructions are received, performs transmission at the transmission interval V _y. Since the transmitting side computer (1) is lowered transmission rate, the time T ₂ later, the data in the receiving buffer unit 20 is not accumulated, the sending computer (2) narrows the transmission interval and the transmission interval V _2, V ₃ You can go. However, when the transmission is performed with the transmission interval set to V ₃ , the data starts to be accumulated again at time T _3, so that the receiving computer has “the data transmission speed> the data processing speed” this time to the transmitting computer (2). To the effect. Sender computer (2) after the instruction receiving, returning the transmission interval V _2. Then, in the following time T ₄ the transmission interval is changed, the data is not stored in the receiving buffer unit 20.

In the flow control method according to the present embodiment,
The following effects are obtained as compared with the first embodiment. When the receiving buffer unit is common, data transmission / reception can be performed without causing a buffer overflow even when one computer newly starts communication while a plurality of computers are communicating in a steady state. .

Embodiment 4 Next, a fourth embodiment will be described. The components constituting the computer 1 according to the fourth embodiment are as shown in FIG. 13, and in addition to the reception-side computer 2 shown in the third embodiment, a transmission device identification unit 24
Has a communication priority table 41 therein. In addition, the reception buffer unit 20 and the reception buffer monitoring unit 2 in the present embodiment
As in the third embodiment, each computer 1 has only one, regardless of the number of connections. Further, the transmission-side computer 1 and the reception buffer unit 2 according to the fourth embodiment.
0, a reception buffer monitoring unit 21, a reception data processing unit 22,
The functions of the data transmission speed setting unit 23, the network 6, and the transmission state table 31 are the same as those of the third embodiment. The communication priority table 41 in the fourth embodiment has a role of holding the communication priority value of the computer N. As the communication priority in the present embodiment, for example, of the amount by which the received data processing unit 22 of the receiving computer processes data,
The ratio of the amount of data transmitted by each transmitting computer can be considered.

FIGS. 14 and 15 show operation procedures of the transmitting computer and the receiving computer in the fourth embodiment, respectively. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

FIG. 14 shows the operation procedure of the transmitting computer. The difference between the operating procedure of the transmitting computer in the third embodiment and the operating procedure of the transmitting computer in the fourth embodiment is that, in the third embodiment, in step S202, the transmission speed is changed from the receiving computer to the current speed. In the fourth embodiment, an instruction is issued to set (the number of computers communicating in the steady state) ÷ (the number of computers communicating in the steady state + 1) times. This is the point to be set accordingly. In the present embodiment, step S3
At 02, the receiving computer sets the transmission speed to (the value of the communication priority of the own computer) / (the sum of the communication priorities of all the communicating computers) times the current speed.

FIG. 15 shows the operation procedure of the receiving computer. The difference between the operating procedure of the receiving computer in the third embodiment and the operating procedure of the receiving computer in the fourth embodiment is that, in the third embodiment, all the computers except the computer that newly started transmission in step S225 are used. , Deceleration of the current transmission speed (the number of computers communicating in the steady state) ÷ (the number of computers communicating in the steady state + 1) times, and required an even deceleration level. The fourth embodiment is characterized in that a request is made to change the value to a value corresponding to the priority of the own computer and transmit the changed value. In the present embodiment, in step S325, the current transmission speed (the value of the communication priority of each computer) ÷ (the communication of all the communicating computers) is given to all the computers except the computer that has newly started transmission. (Sum of priorities).

In the flow control method according to the present embodiment,
The following effects are obtained as compared with the third embodiment. Rather than all calculators slowing down at a uniform deceleration level,
Transmission can be performed at a communication speed different from that of the other computers according to the priority, and even in this case, a buffer overflow does not occur.

Embodiment 5 FIG. Next, a fifth embodiment will be described. The components constituting the transmitting computer 1 and the receiving computer 2 in the fifth embodiment are the same as those in the third embodiment, and are shown in FIG. It is assumed that each computer has only one reception buffer unit 20 and one reception buffer monitoring unit 21 in the present embodiment, regardless of the number of connections, as in the third embodiment. The role of each component in the fifth embodiment is the same as in the third embodiment.

The fifth embodiment is an extension of the method of the third embodiment. When the receiving computer is communicating with n steady-state transmitting computers, a plurality of new communications are started. A method for setting the data transmission speed for the transmitting computer will be described. FIG. 16 and FIG.
FIG. 19 shows operation procedures of a transmitting computer and a receiving computer in the fifth embodiment. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

First, the operation procedure of the transmitting computer will be described. The transmitting computer sets the lowest transmission speed V (step S401). First, data transfer is performed at the data transmission speed determined in step S401 (step S402).
Then, it is checked whether or not a notification (increase prohibition instruction message) for notifying “transmission rate change (increase) inhibition” has been received from the receiving computer.
Proceeding to 4, the appropriate transmission rate is determined by the same method as in the first embodiment (steps S404 to S408), and data transmission is performed in a steady state. In step S403,
When a “transmission speed change (increase) prohibition” notification (increase prohibition instruction message) is received from the receiving computer, step S40 is performed.
9, data transmission is performed at the minimum transmission speed V (step S40) until a "transmission rate change (increase) possible" notification (increase instruction message) is received (step S410).
9). In step S410, when a “transmission rate changeable” notification (increase instruction message) is received, step S404 is performed.
To determine the transmission rate in the same manner as in Embodiment 1,
After the transmission speed is determined, data transmission is performed in a steady state. The behavior of the sending computer after the steady state is described in the third embodiment.
The description is omitted because it is the same as (FIG. 10).

Next, the operation procedure of the receiving computer will be described (FIG. 17). All the transmitting computers are in the steady state, and the behavior of the receiving computer when receiving data from the computer communicating in the steady state is the same as that of the third embodiment, and therefore the description is omitted (step S421). Step S
At 422, if all of the transmitting computers are in the steady state and new data has arrived from a new transmitting computer that is not in the steady state, the process proceeds to step S423. Step S4
At 23, the data transmission speed setting unit 23 prohibits a computer that has newly started communication from changing (rising) the transmission speed. Specifically, this is performed by transmitting an ascending prohibition instruction message from the data transmission speed setting unit 23. afterwards,
In step S424, the data transmission speed setting unit 23
Requests the computers (n) communicating in the steady state to increase the transmission speed by n ÷ (n + 1) times. Step S42
In 5, the received data processing unit 22 processes the received data, and then starts a new communication (not in a steady state).
Notify the computer of "transmission rate change (increase) permission". Specifically, the data transmission speed setting unit 23 performs the transmission by transmitting an ascending instruction message. As a result, the transmission-side computer that has newly started communication increases the speed in a stepwise manner, similarly to the procedure described in the first embodiment.
The data transmission speed is set. After that, the process waits for the arrival of data again (step S427). When the data arrives, the data transmission speed setting unit 23 refers to the transmission state table 31 (step S428) to check whether the data is from the computer currently communicating (step S428). Step S42
9) If the data is from a new transmission-side computer that is not currently communicating, a request for “prohibition of change in transmission speed” is transmitted to the computer (in this way, transmission newly started this time). The side computer transmits at the lowest speed until the "transmission speed change permission" notification is transmitted from the receiving computer.) If the result of determination in step 429 is that the data is transmitted from the transmitting computer currently communicating, in step S431, the received data processing unit 22 processes the data received, and the reception buffer monitoring unit 21 Reference is made to the reception buffer unit 20. As a result of monitoring by the reception buffer monitoring unit 21, if data has already arrived at the reception buffer unit 20, the data transmission capability of the transmission-side computer group exceeds the processing capability of the reception-side computer. A request to lower the transmission speed is transmitted to the computer that has newly started transmission in step S422 (step S433). As a result, the data transmission speed of the transmission-side computer that has newly started transmission is set, and a steady state is set. Also, in step 434,
The data transmission speed setting unit 23 confirms whether or not data has arrived from the computer that has newly started transmission in step S429 during the processing of steps S423 to S433 (step S434). If data has arrived from the sending computer of step S435,
Then, one of the computers that has newly started transmission is selected, and the processing of steps S424 to S433 is performed. Note that the instruction of “prohibit change of transmission speed (increase)”, which is the process of step S423, has already been performed in step S430, so the process starts from step S424. Steps S424 to S433 are continued until all the communicating computers are in the steady state.

The flow control system according to this embodiment has the following effects as compared with the third embodiment. In the third embodiment, when all the communicating computers are in the steady state, this is effective when one computer newly starts transmission. However, in the third embodiment, a plurality of computers communicate simultaneously. Can be dealt with even when the process is started.

Embodiment 6 FIG. Next, a sixth embodiment will be described. The components constituting the transmitting computer 1 and the receiving computer 2 in the sixth embodiment are the same as those in the third embodiment, and are shown in FIG. It is assumed that each computer has only one reception buffer unit 20 and one reception buffer monitoring unit 21 in the present embodiment, regardless of the number of connections, as in the third embodiment. The role of each component in the sixth embodiment is the same as in the third embodiment.

FIGS. 18 and 19 show Embodiment 6 respectively.
3 shows the operation procedure of the transmitting computer and the receiving computer in FIG. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

First, FIG. 18 shows the operation procedure of the transmitting computer (FIG. 18). The data transmission speed adjusting unit 11 of the transmission side computer 1 sets the minimum transmission speed V (step S501). Then, data transfer is performed at the data transmission rate determined in step S501 (step S5).
02). Then, it is confirmed whether or not the "proper transmission speed value" is transmitted from the receiving computer (step S503).
If not, the process proceeds to step S505, where the transmission speed is determined by the same method as in the first embodiment, and data transmission is performed in a steady state. In step S503, when a notification of the “appropriate transmission speed value” is received from the receiving computer, step S503
Proceeding to 504, the transmission speed is changed to the value received from the receiving computer, and data transmission is performed.

FIG. 19 shows the operation procedure of the receiving computer. In step S521, the process waits for the arrival of data. When the data arrives, the transmitting device identifying unit 24 refers to the transmission status table 31 to determine whether the data is from the computer currently communicating or the computer that has newly started transmission. It is checked whether it is a body (step S522). If it is a new transmission, it is checked whether or not all of the transmitting computers are currently in a steady state. If all are in a steady state, the process proceeds to step S524, and the data transmission speed setting unit 23
The transmission speed of the entire transmission-side computer is determined from the amount of data per unit time being transmitted by the currently transmitting (n) computers, and a value obtained by dividing the transmission speed by (n + m) (where m is a new transmission start) (The number of computers) to request transmission to all the computers, and returns to step S521.

In the flow control method according to the present embodiment,
The following effects are obtained as compared with the fifth embodiment. In the fifth embodiment, the transmission speed is determined by gradually increasing the transmission speed from the lowest transmission speed even when all the communicating computers are in the steady state. An appropriate transmission speed can be quickly obtained by calculating the transmission speed at which no overflow occurs in the computer and notifying the transmission side computer of the transmission speed.

Embodiment 7 FIG. Next, a seventh embodiment will be described. The components constituting the computer 1 in the seventh embodiment are the same as those in the third embodiment, and
Shown in The function of each element constituting the computer according to the seventh embodiment is the same as that of the third embodiment.

FIGS. 20 and 21 show operation procedures of the transmitting computer and the receiving computer in the seventh embodiment, respectively. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

First, the operation procedure of the transmitting computer will be described with reference to FIG. The behavior up to the steady state is the same as that of the third embodiment, and a description thereof will be omitted. While transmitting data in a steady state in step S601, the system waits for a notification (increase instruction message) notifying that "data transmission speed <reception data processing speed" from the receiving computer (step S602). In step S602,
When comes notification that "data transmission rate <received data processing speed", the process proceeds to step S603, and records the transmission speed data transmission speed adjusting section 11 is currently transmitting as V _2. Then, the transmission speed is increased by one level (step S6).
04), and perform data transmission (step S605). Data transmission is performed for a certain period of time at the transmission speed set in step S604, and a notification (deceleration instruction message) notifying “data transmission speed> reception data processing speed” is received from the receiving computer within that time (step S604). S60
6), it means that the transmission speed is too fast, the data transmission speed adjusting section 11 returns the transmission rate to the transmission speed V ₂ which is recorded in step S603 (step S608), the flow returns to step S601. If a notification notifying that “data transmission speed> reception data processing speed” is not received within the specified time, it means that the reception data processing capability of the receiving computer is higher, and therefore the transmission speed is not changed and step S601 is performed. Return to

Next, the operation procedure of the receiving computer will be described (FIG. 21). First, it waits for the arrival of data (step S621).
2 processes the data (step S622), and in step S623, the reception buffer monitoring unit 21 refers to the amount of the buffer stored in the reception buffer unit 20, and the data amount stored in the reception buffer unit 20. Is decreased, the data transmission speed setting unit 23 selects one computer from the transmitting computers currently transmitting at step S624 (i) and issues an instruction to the transmitting computer i to increase the transmission speed. (Step S625). Then, it waits for the arrival of data again (step S626), and after the arrival of data, the received data processing unit 22 processes the data (step S626).
Then, the reception buffer monitoring unit 21 refers to the amount of data stored in the reception buffer unit 20. At this time, if the amount of data stored in the reception buffer unit 20 is larger than that at the time confirmed in step S623, the total amount of data transmitted in a unit time exceeds the data processing capability of the receiving computer. Therefore, the data transmission speed setting unit 23
The transmission-side computer i is informed that “data transmission speed> reception data processing speed” (step S629), and the process returns to step S621. If the amount of data stored in the reception buffer unit is smaller than that at the time of confirmation in step S623, it means that the processing capability of the reception data processing unit is higher than the data transmission speed.
Then, the same operation is repeated until “data transmission speed> reception data processing speed”. As a reference for selecting the transmission-side computer i, for example, selection of a computer with a low (or high) transmission speed, selection of a computer with a high priority, and the like can be considered.

In the flow control method according to the present embodiment,
The following effects are obtained as compared with the third embodiment. When the communication of the computer in the steady state ends, the amount of data stored in the reception buffer decreases. According to the method described in the present embodiment, when the amount of data stored in the reception buffer unit is reduced, the data transmission speed can be improved to a level not exceeding the reception data processing capability.
Data transmission can be performed efficiently.

Embodiment 8 FIG. Next, an eighth embodiment will be described. The components constituting the transmitting computer 1 and the receiving computer 2 in the eighth embodiment are the same as those in the third embodiment, and are shown in FIG. Note that the data transmission method and the data reception method according to the present invention are realized by the same procedure.

FIGS. 22 and 23 show operation procedures of the transmitting computer and the receiving computer in the eighth embodiment, respectively.

First, the operation procedure of the transmitting computer will be described with reference to FIG. The behavior up to the steady state is the same as in the third embodiment, and will not be described. If you want to increase the transmission rate to the midst of data transmission in the steady state, a request to increase speed (V) than V _x transmitted at Step S701 (elevated permission request) data transmission unit 12
Send it out to the receiving computer. Then, while waiting for reception of the permission to increase the transmission rate from the receiving computer (up indication message) (step S702) and transmits the data at a transmission rate V _x (Step S703). Step S702
Then, when a permission to increase the transmission rate (an increase instruction message) is obtained from the receiving computer, the data transmission rate adjusting unit 11
Retaining the current data transmission rate a value of (V) with the data transmission speed adjusting section 11 (a V ₂₎ (step S704),
The data transmission speed is increased by one level (step S705), and data is transmitted at the speed set in step S705 (step S706). Data is transmitted for a predetermined time at the speed set in step S705 (step S706).
In the meantime, if a notification (deceleration instruction message) indicating that “data transmission speed> data processing speed” is received from the receiving computer, the data transmission speed adjustment unit 11 sets the currently transmitted transmission speed to the data transmission speed adjustment unit. 11 (step S708), and again at step S702.
Then, data transmission is performed at the transmission rate set in step S708 until a permission to increase the speed (upward instruction message) is received from the receiving computer. Step S707
In, the receiving side computer, if not come "data transmission rate> data processing speed" notification, compared whether the value of the current transmission rate is smaller than V _x (Step S71
0), if smaller, the process returns to step S704, and
Steps 704 to S709 are repeated. In step S710, if the value of the current transmission speed V _x or more,
A transmission speed increase end notification is transmitted to the receiving computer (S71).
1) and the transmission is continued at that speed (step S71).
2).

Next, the operation procedure of the receiving computer will be described with reference to FIG. The receiving computer waits for data arrival (S721), and processes the arrived data (S721).
722), "Request to increase transmission speed" from the transmitting computer
(Upgrade permission request) arrives. When a “request to increase the transmission speed” arrives from the transmitting computer (A), the data transmission speed setting unit 23 sends a request to computers other than the computer A to
A request is made to lower the transmission speed (step S724), and data arrival is waited for (step S725), and the received data processing unit 22 processes the received data (step S726).
While waiting for the amount of data stored in the reception buffer unit to decrease. If the amount of data stored in the reception buffer unit decreases in step S727, it means that the processing capability of the reception data processing unit has a margin, and the data transmission speed setting unit 23 sends the transmission speed to the computer A. A message is sent to the effect that may be raised. And
Waiting for data arrival, the received data processing unit 22 processes the received data.

After the data processing, the amount of data stored in the reception buffer unit is checked (step S731), and S727
If the data amount is larger than the data accumulation amount in the above, it means that the data transmission speed exceeds the processing capability of the received data, and the data transmission speed setting unit 23 sends the data to the computer A in step S732. A notification that "data transmission speed> reception data processing speed" is given (deceleration instruction message), and the process returns to step S724 to request a computer other than computer A to reduce the transmission speed. Step S
At 731, if the data amount has not increased, step S
729 to S731 are repeated. If the data amount does not increase and a "transmission speed increase end notification" is received from the transmitting computer, the process returns to step S721 to perform the conventional data reception in a steady state.

In the flow control method according to the present embodiment,
The following effects are obtained as compared with the third embodiment. In the third embodiment, once the computer enters a steady state, the transmission speed cannot be improved. However, the data transmission speed of the computer can be increased by the method described in the present embodiment. In addition, since the data transmission speed of the transmitting computer is reduced and the data transmission speed of the target computer is improved by utilizing the surplus received data processing capability, the reception buffer does not overflow.

The features of the present invention described so far are summarized as follows. A flow control method in which a plurality of computers are connected by a network, and a data transmission side computer transmits and receives data while synchronizing with a data reception side computer. The flow control type data transmitting side computer having the effect of preventing the overflow of the reception buffer unit by transmitting the data and further reducing the reception buffer size has a transmission control unit for recording the transmission speed. The data receiving computer has a reception buffer monitoring unit that monitors the amount of data stored in the reception buffer. The data transmission side computer starts data transmission at the lowest speed, gradually increases the data transmission speed, and records the speed before the increase in the transmission control unit every time the speed is increased. The data receiving computer checks whether data has been accumulated in the reception buffer by the reception buffer monitoring unit while processing the received data. When data is accumulated in the reception buffer, the data receiving computer instructs the data transmitting computer not to increase the transmission speed. Upon receiving the instruction from the data receiving computer, the data transmitting computer immediately stops increasing the transmission speed, changes the transmission speed to a value recorded in the transmission control unit, and continues data transmission.

The following features are added to the above-described configuration, and the flow control method which has an effect of shortening the data transmission time by transmitting a large amount of data while the reception buffer has free space has a data receiving side. When receiving an instruction from the side computer not to increase the transmission speed, data transmission is continued at the speed at which the instruction was received. The data reception side computer processes the received data while the reception buffer monitoring unit monitors the amount of data accumulated in the reception buffer. When a predetermined amount of data is accumulated in the reception buffer, the data receiving computer instructs the data transmitting computer to reduce the transmission speed. Upon receiving the instruction from the data receiving computer, the data transmitting computer immediately changes the transmission speed to the value recorded in the transmission control unit and continues data transmission.

The following features are added to the above-described configuration, and when one or more computers are transmitting data to the receiving computer at an appropriate transmission speed, a buffer overflow does not occur even if another computer starts new data transmission. The flow control system computer having an effect has a transmission state table indicating three communication states of transmitting at an appropriate transmission speed, transmission speed undetermined, and untransmitted. When the data arrives, the receiving computer refers to the transmission state table to check whether the data has come from a computer that has been transmitting at an appropriate transmission speed so far, and uses the data from the computer that has newly started transmission. If there is, an instruction is issued to all the computers other than the computer to reduce the data transmission speed. All the computers that have been communicating at the appropriate transmission speed until now receive the instruction from the receiving computer, lower the data transmission speed, and continue data transmission at the reduced speed. The computer that has newly started data transmission increases the transmission speed until the receiving computer instructs not to increase the transmission speed.

The above configuration has the following characteristics in the transmitting computer, and has a flow control method capable of changing the transmission speed according to the transmission priority of each transmitting computer. Each computer stores the communication priority. Communication priority table. When all the computers communicating at an appropriate transmission speed are instructed to reduce the transfer speed by the receiving computer, the transfer speed is reduced according to the priority of the own computer.

The following features are added to the above configuration, and the flow control system receiving side computer having the effect of preventing overflow even when two or more computers start communication at the same time, when the data arrives, sets the transmission state table. For reference, if there is a computer that has newly started data transmission and another computer that is not transmitting data at an appropriate transmission speed, the computer that has newly started data transmission will receive data at the minimum speed. Is transmitted. The receiving computer requests a computer that is transmitting data at an appropriate transmission speed to reduce the transmission speed. And
Select one computer that is not performing data transmission at an appropriate transmission speed, and instruct the computer to increase the transfer speed. This operation is repeated until there is no computer whose transmission rate is not determined.

With respect to the above configuration, an appropriate data transmission rate is obtained in advance by a receiving computer for a computer that has newly started data transmission, and the value is transmitted to the computer that has newly started data transmission, The computer is a flow control method that has the effect of shortening the time from the start of data transmission to obtaining an appropriate transmission speed by performing data transmission with the value transmitted from the receiving computer.

The following features are added to the above configuration, and the reception buffer monitor of the flow control system receiving side computer having the effect of using the reception buffer efficiently monitors the amount of data accumulated in the reception buffer, and When the number starts to decrease, one computer is selected and an instruction to improve the communication speed is issued.

The following features are added to the above configuration, and even if a certain computer increases the communication speed during communication, communication is performed without causing overflow. Request to increase the communication speed. Upon receiving the request, the receiving computer issues an instruction to all the computers currently communicating to reduce the communication speed, and notifies the computer that issued the request that the communication speed has been increased. The transmitting computer that has issued the request increases the communication speed after receiving the permission of the request from the receiving computer.

[0089]

According to the present invention, the transmitting computer starts data transmission at a transmission speed lower than the reception data processing speed, so that the possibility of overflow can be eliminated, and the transmission computer is smaller than the conventional system. Data communication can be performed using the reception buffer buffer size.

Further, according to the present invention, when there is enough free space in the buffer, by transmitting a large amount of data to the reception buffer unit and storing the data, the transmission processing of the transmission-side computer can be completed quickly. it can.

Further, according to the present invention, when the receiving buffer unit is common, even when one computer newly starts communication while a plurality of computers are performing communication in a steady state, the buffer overflow occurs. Data transmission / reception can be performed without causing a problem.

Not all the computers decelerate at a uniform deceleration level, but can transmit at a different communication speed from other computers according to the priority. In this case, no buffer overflow occurs. .

Further, according to the present invention, the data transmission speed can be determined without causing a buffer overflow even when a plurality of computers start communication simultaneously when all the communicating computers are in a steady state.

Further, according to the present invention, an appropriate transmission speed can be quickly obtained by obtaining the transmission speed at which overflow does not occur at the receiving computer and notifying the transmitting computer of the transmission speed.

Further, according to the present invention, when the amount of data stored in the reception buffer unit is reduced, the data transmission speed can be improved so as not to exceed the reception data processing capability. It can be performed efficiently.

Further, according to the present invention, the data transmission speed can be improved even after the computer enters a steady state. In addition, by lowering the data transmission speed of other transmitting computers and utilizing the surplus received data processing capacity,
Since the data transmission speed of the target computer has been improved,
The overflow of the reception buffer does not occur.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a transmitting computer and a receiving computer according to Embodiment 1 of the present invention.

FIG. 2 is another diagram showing a configuration of a transmitting computer and a receiving computer according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of the transmitting computer according to the first embodiment of the present invention.

FIG. 4 is a flowchart showing the operation of the receiving computer according to the first embodiment of the present invention.

FIG. 5 is a diagram showing a relationship between a transmission speed and a reception buffer according to Embodiment 1 of the present invention.

FIG. 6 is a flowchart showing the operation of the transmitting computer according to the second embodiment of the present invention.

FIG. 7 is a flowchart showing the operation of the receiving computer according to the second embodiment of the present invention.

FIG. 8 is a diagram showing a relationship between a transmission speed and a reception buffer according to Embodiment 2 of the present invention.

FIG. 9 is a diagram showing a configuration of a transmitting computer and a receiving computer according to Embodiment 3 of the present invention.

FIG. 10 is a flowchart showing the operation of the transmitting computer according to Embodiment 3 of the present invention.

FIG. 11 is a flowchart showing the operation of the receiving computer according to Embodiment 3 of the present invention.

FIG. 12 is a diagram illustrating a relationship between a transmission speed and a reception buffer according to Embodiment 3 of the present invention.

FIG. 13 is a diagram showing a configuration of a transmitting computer and a receiving computer according to Embodiment 4 of the present invention.

FIG. 14 is a flowchart showing the operation of the transmitting computer according to Embodiment 4 of the present invention.

FIG. 15 is a flowchart showing an operation of the receiving computer according to the fourth embodiment of the present invention.

FIG. 16 is a flowchart showing the operation of the transmitting computer according to the fifth embodiment of the present invention.

FIG. 17 is a flowchart showing the operation of the receiving computer according to Embodiment 5 of the present invention.

FIG. 18 is a flowchart showing the operation of the transmitting computer according to Embodiment 6 of the present invention.

FIG. 19 is a flowchart showing an operation of the receiving computer according to the sixth embodiment of the present invention.

FIG. 20 is a flowchart showing the operation of the transmitting computer according to the seventh embodiment of the present invention.

FIG. 21 is a flowchart showing an operation of the receiving computer according to the seventh embodiment of the present invention.

FIG. 22 is a flowchart showing the operation of the transmitting computer according to the eighth embodiment of the present invention.

FIG. 23 is a flowchart showing an operation of the receiving computer according to the eighth embodiment of the present invention.

FIG. 24 is a diagram showing a relationship between a transmission speed and a reception buffer according to a conventional technique.

[Explanation of symbols]

1 transmitting computer, 2 receiving computer, 6 network, 10 instruction message receiving unit, 11 data transmission speed adjusting unit, 12 data transmitting unit, 20 receiving buffer unit, 21 receiving buffer monitoring unit, 22 received data processing unit, 23 data Transmission speed setting unit, 24 transmission device identification unit, 31 transmission status table, 41 communication priority table.

Claims (20)

[Claims] 1. A data transmission device for adjusting data transmission speed and transmitting data by communicating with a data reception device, comprising: receiving an instruction message from the data reception device instructing adjustment of the data transmission speed. An instruction message receiving unit to perform the data transmission speed until the instruction message is received by the instruction message receiving unit, and when the instruction message is received, the data transmission speed according to the instruction message. A data transmission speed adjusting unit for adjusting the data transmission speed. 2. The instruction message receiving unit receives, as the instruction message, a deceleration instruction message for instructing deceleration of the data transmission speed, and the data transmission speed adjustment unit performs the deceleration instruction by the instruction message receiving unit. Until a message is received, the data transmission speed is increased step by step, and the data transmission speed in each of the ascending stages is recorded.When the instruction message receiving unit receives the deceleration instruction message, 2. The data transmission apparatus according to claim 1, wherein the data transmission speed is switched to a data transmission speed lower than the data transmission speed when the deceleration instruction message was received, based on the recording of the data transmission speed in the step. 3. The instruction message receiving unit receives, as the instruction message, an ascending prohibition instruction message that inhibits an increase in the data transmission rate, and the data transmission rate adjusting unit performs the ascending by the instruction message receiving unit. The data transmission device according to claim 1, wherein a data transmission speed when a prohibition instruction message is received is maintained. 4. The instruction message receiving unit receives, as the instruction message, an increase instruction message instructing an increase in the data transmission rate, and the data transmission rate adjustment unit controls the increase instruction by the instruction message receiving unit. 3. The data transmission device according to claim 1, wherein after the message is received, the data transmission speed is increased until the deceleration instruction message is received. 5. The data transmitting device includes a request transmitting unit that transmits an increase permission request for requesting an increase in the data transmission speed, wherein the instruction message receiving unit is transmitted by the request transmitting unit. The data transmission device according to claim 4, wherein the ascending instruction message is received as ascending permission with respect to the ascending permission request. 6. A data transmission apparatus that receives data from a data transmission apparatus that transmits data while increasing the data transmission rate stepwise, and sets the data transmission rate of the data transmission apparatus within an allowable range of its own received data processing capability. A data reception device, comprising: a reception buffer unit that receives data transmitted from the data transmission device and stores the received data; and reception data that performs a reception process of the reception data stored in the reception buffer unit. A processing unit; a reception buffer monitoring unit that monitors a storage amount of the reception data stored in the reception buffer unit; and a storage amount of the reception data reaching a predetermined level based on a monitoring result by the reception buffer monitoring unit. Until the above, the data transmission speed is increased step by step by the data transmission device, and the accumulated amount of the received data reaches a predetermined level. When it is determined that the data transmission speed exceeds the allowable range of the reception data processing capacity of the reception data processing unit, the data transmission device instructs the data transmission device to reduce the data transmission speed. A data receiving device comprising a speed setting unit. 7. The data transmission speed setting unit, based on a result of monitoring by the reception buffer monitoring unit, until the storage amount of the reception data reaches a first level, the data transmission device sets the data transmission speed. Step by step, and when the amount of storage of the received data reaches the first level, prohibits the data transmission device from increasing the data transmission speed, and the amount of storage of the received data becomes Is reached, it is determined that the data transmission speed has exceeded the allowable range of the reception data processing capacity of the reception data processing unit, and the data transmission device is instructed to reduce the data transmission speed. 7. The data receiving device according to claim 6, wherein: 8. A data receiving device that receives data from a plurality of data transmitting devices and sets a data transmission speed of the plurality of data transmitting devices within an allowable range of its own received data processing capability. Among the data transmission devices, a data transmission device identification unit that identifies a transmission speed set device that has set the data transmission speed, and a transmission speed unset device that has not set the data transmission speed. Instructs the transmission speed-set device identified by the device identification unit to reduce the data transmission speed, and sets the reception data processing capacity to the transmission speed not set based on the data transmission speed reduction of the transmission speed-set device. A data transmission speed setting unit for setting the data transmission speed of the device for which the transmission speed has not been set, which is distributed to the devices. 9. The data transmission speed setting unit increases the data transmission speed of the transmission speed non-setting device in a stepwise manner within an allowable range of the reception data processing capability, and transmits the data of the transmission speed non-setting device. 9. The data receiving device according to claim 8, wherein a transmission speed is set. 10. The data transmission speed setting unit, based on a ratio between the number of the transmission speed-set devices and the total number of the plurality of data transmission devices, to the data transmission speed-setting device. 9. The data receiving apparatus according to claim 8, wherein the data deceleration level is instructed. 11. The data transmission device identification unit identifies a priority set for each of the plurality of data transmission devices, and the data transmission speed setting unit identifies a priority identified by the data transmission device identification unit. 9. The data receiving apparatus according to claim 8, wherein a data transmission speed reduction level is instructed to the transmission speed set apparatus according to the degree. 12. The data transmission speed setting unit prohibits the transmission speed unset device from increasing the data transmission speed, and instructs the transmission speed setting device to reduce the data transmission speed. 10. The data receiving apparatus according to claim 9, wherein the prohibition of the increase in the data transmission speed for the transmission speed non-set device is canceled and the data transmission speed of the transmission speed non-set device is set. 13. The data transmission speed setting unit instructs the transmission speed setting device to decelerate to a predetermined data transmission speed and transmits the same data transmission speed as the predetermined data transmission speed. 9. The data receiving device according to claim 8, wherein the data receiving speed is set as a data transmission speed for a device whose speed is not set. 14. The data transmission rate setting unit, wherein the predetermined data transmission rate is a value obtained by dividing a total of data transmission rates set for the transmission rate-set apparatuses by the total number of the plurality of data transmission apparatuses. 14. The data receiving apparatus according to claim 13, wherein the data receiving speed is set. 15. The data transmission speed setting unit instructs the transmission speed setting device to increase the data transmission speed, and within an allowable range of the reception data processing capability,
9. The data receiving device according to claim 8, wherein the data transmission speed of the transmission speed-set device is increased stepwise, and a new data transmission speed is set for the transmission speed-set device. 16. The data receiving apparatus further includes a request receiving unit that receives an increase permission request that is transmitted from the transmission rate set apparatus and that requests an increase in the data transmission rate. The transmission speed setting unit, for the transmission speed set device that has transmitted the increase request received by the request receiving unit, permits the increase of the data transmission speed, within an allowable range of the received data processing capability, 16. The data receiving apparatus according to claim 15, wherein a data transmission rate of the apparatus for which the transmission rate has been set is increased stepwise, and a new data transmission rate is set for the apparatus for which the transmission rate has been set. 17. A data transmission method for transmitting data by adjusting a data transmission speed by communicating with a data reception method, comprising: receiving an instruction message instructing the data transmission speed adjustment from the data reception method. An instruction message receiving step of: increasing the data transmission rate until the instruction message is received by the instruction message receiving step; and, when the instruction message is received, the data transmission rate according to the instruction message. Adjusting the data transmission rate. 18. The instruction message receiving step,
As the instruction message, a deceleration instruction message for instructing deceleration of the data transmission speed is received, and the data transmission speed adjusting step comprises: receiving the deceleration instruction message until the deceleration instruction message is received by the instruction message receiving step. While increasing in steps, recording the data transmission speed in each of the ascending stages, when the deceleration instruction message is received in the instruction message receiving step, based on the recording of the data transmission speed in each of the stages, the deceleration The data transmission method according to claim 17, wherein the data transmission rate is switched to a data transmission rate lower than the data transmission rate when the instruction message was received. 19. A method for receiving data by a data transmission method of transmitting data by increasing the data transmission speed stepwise,
A data reception method for setting a data transmission rate of the data transmission method within an allowable range of its own reception data processing capability, the method comprising: receiving data transmitted by the data transmission method; and storing received data. A data storage step, a reception data processing step of performing reception processing of the reception data stored in the reception data storage step, and a reception data storage amount for monitoring a storage amount of the reception data stored in the reception data storage step A monitoring step, based on a monitoring result of the received data storage amount monitoring step, increasing the data transmission speed stepwise by the data transmission method until the storage amount of the received data reaches a predetermined level; When it is determined that the data storage amount has reached a predetermined level, the data transmission speed Determining that the received data processing capacity of the received data processing step has exceeded an allowable range, and instructing the data transmission method to reduce the data transmission speed. Data receiving method to be used. 20. A data receiving method for receiving data from a plurality of data transmission methods and setting data transmission speeds of the plurality of data transmission methods within an allowable range of own received data processing capability, A data transmission method identification step of identifying a transmission speed setting method that sets the data transmission speed and a transmission speed non-setting method that does not set the data transmission speed among the data transmission methods; Instructing the method for setting the transmission speed identified by the method identification step to reduce the data transmission speed, and setting the reception data processing capability to the transmission speed not set based on the reduction in the data transmission speed of the method for which the transmission speed has been set. And a data transmission rate setting step of setting a data transmission rate in the transmission rate non-setting method. Data receiving method.