JP2002290489A - Communication system and communication control device using plural circuits - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a communication system and a communication control device reducing communication cost and securing reliability by setting a plurality of low speed circuits in communications between remote place computers into normal circuits and standby circuits, and further assigning the normal circuits to data and error correcting codes and using number of stand-by circuits corresponding to the amount of the transfer data. SOLUTION: The communication circuits connecting the communication control device 20A and the communication control device 20B consists of normal circuits comprising one or more circuits which transfer data and one or more circuits which transfer the error correction codes, and standby circuits comprising one or more standby circuits which are used connected in response to the amount of data transfer. The communication control device 20A monitors storage amount of transmitted data stored in a transmission buffer 41 which holds the transmitted data for a while, and if the transmitted data storage amount exceeds a specified increase value, one or more standby circuits are connected, and if the transmitted storage amount decreases to below a specified decrease value, one or more standby circuits are cut off.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication system and a communication control device using a plurality of lines, and more particularly to using a plurality of low-speed and inexpensive lines and adjusting the number of connection lines within a certain range according to the data transfer amount. The present invention also relates to a communication technique in which a line for an error correction code is provided separately from data.

[0002]

2. Description of the Related Art In a conventional communication system, a computer group A
In the data communication between the remote computer group B and the computer group B in a remote place, a dedicated high-speed line is always contracted and laid in order to maintain high-quality and high-speed data transfer. Further, it is necessary to determine the number of lines so as to satisfy the communication capability at the time when the data transfer amount is maximized.

[0005] Further, there has been proposed a method of securing communication capability by using a plurality of low-speed lines such as public lines under contract. With this method, it is also possible to reduce the communication cost by increasing or decreasing the number of lines used according to the data transfer amount.

[0004]

However, the conventional communication system has the following problems. A first problem is that when a dedicated line is used, the cost required for communication increases. Moreover, since the capacity of the line must be determined according to the maximum transfer amount, the efficiency is low and the cost is higher than the transfer amount.

A second problem is that the method using a plurality of low-speed lines is less reliable than a dedicated line. Furthermore, because the number of used lines is frequently switched according to the transfer amount, when the transfer amount increases, the processing overhead for connecting the lines may delay the processing,
There was also a problem that the ability was reduced.

An object of the present invention is to solve these problems and set a plurality of low-speed lines as a service line and a protection line,
In addition, the service line is allocated to data and error correction code,
It is an object of the present invention to provide a communication system and a communication control device that reduce communication costs and ensure reliability by using the number of spare lines according to the transfer amount.

[0007]

A first communication system according to the present invention is a communication system for transferring data from a communication control device A to a communication control device B via a communication line, wherein the communication line is always in communication. A group of two or more regular lines to be connected and one or more spare lines connected according to the data transfer amount, wherein the regular line group includes one or more lines for transferring data and an error correction code. It comprises one or more lines for transfer.

A second communication method according to the present invention is a communication method for transferring data from a communication control device A to a communication control device B via a communication line, wherein the communication line includes at least one data transfer device. The communication control device A is composed of a regular line group that is always in a connected state and includes a line and one or more lines that transfer an error correction code, and one or more spare lines that are connected according to a data transfer amount. A transmission buffer for temporarily storing transmission data, monitoring a transmission data accumulation amount accumulated in the transmission buffer, and when the transmission data accumulation amount becomes equal to or more than a predetermined increase specified value, one or more lines are transmitted. A protection line is connected, and one or more protection lines are cut off when the transmission data storage amount becomes equal to or less than a predetermined decrease specified value.

A third communication system according to the present invention is a communication system for transferring data from a communication control device A to a communication control device B via a communication line, wherein the communication line includes at least one data transfer device. The communication control device A is composed of a regular line group that is always in a connected state and includes a line and one or more lines that transfer an error correction code, and one or more spare lines that are connected according to a data transfer amount. A transmission buffer for temporarily storing transmission data, a data division unit for dividing the data extracted from the transmission buffer into a number obtained by subtracting the number of lines for transmitting the error correction code from the number of communication lines in the connected state, A correction code generation unit that generates an error correction code based on the obtained data, monitors a transmission data storage amount stored in a transmission buffer, and sets the transmission data storage amount to a preset increase specified value. When the above makes a connection of one or more lines of the protection line, and performs cutting of the transmission data when the accumulated amount is equal to or less than a preset reduced prescribed value 1 or more lines of the protection line.

[0010] A fourth communication method according to the present invention is a computer group A including one or more computers A and a communication control device A.
A communication system for transferring data via a communication line to a computer group B including one or more computers B and a communication control device B, wherein the communication line is connected to one or more lines for transferring data and error correction. The communication control device A includes one or more lines that are always connected and includes one or more lines for transferring codes, and one or more lines that are connected according to a data transfer amount. A transmission buffer for temporarily holding the transmission data received from the transmission buffer, and a data dividing unit for dividing the transmission data extracted from the transmission buffer into a number obtained by subtracting the number of lines for transmitting the error correction code from the number of communication lines in the connected state. A correction code generation unit that generates an error correction code based on the divided data; and an error correction unit configured to generate the error correction code based on the divided data received from the data division unit and the correction code generation unit. A line connection unit for transmitting a code to a communication line in a connected state, wherein the communication control device B performs data error based on the divided data and the error correction code received from the communication line in the connected state. The communication control device A monitors the transmission data accumulation amount accumulated in the transmission buffer, and sets the transmission data accumulation amount in advance. One or more protection lines are connected when the increase value is equal to or more than the specified increase value, and one or more protection lines are disconnected when the transmission data accumulation amount is equal to or less than a predetermined decrease value. .

A fifth communication system according to the present invention includes second, third,
Alternatively, in the fourth communication method, the transmission data accumulation amount is determined by a write pointer indicating a writing position when writing transmission data to the transmission buffer and a reading pointer indicating a reading position when reading transmission data from the transmission buffer. It is characterized by being calculated from the difference from the write pointer.

A sixth communication system according to the present invention includes second, third,
Alternatively, in the fourth communication method, the number of the service lines and the number of the protection lines are changed according to a schedule table in which the number of the respective lines is determined in advance corresponding to the date and time.

A first communication control device according to the present invention is characterized in that a communication line for performing data transfer includes one or more lines for transferring data and one or more lines for transferring an error correction code, and is always in a connected state. A transmission buffer that temporarily allocates transmission data and is allocated to a certain regular line group and one or more protection line groups connected according to the data transfer amount, and monitors the amount of transmission data stored in the transmission buffer. When the transmission data accumulation amount is equal to or more than a predetermined increase specified value, one or more protection lines are connected, and when the transmission data accumulation amount is equal to or less than a predetermined reduction specification value, one or more protection lines are connected. A transmission control unit for disconnecting the line.

According to a second communication control device of the present invention, a communication line for performing data transfer includes one or more lines for transferring data and one or more lines for transferring an error correction code, and is always connected. A transmission buffer which temporarily allocates transmission data and is allocated to a certain working line group and one or more protection line groups to be connected according to the data transfer amount, and a communication in which data taken out from the transmission buffer is connected. A data division unit for dividing the number of lines by subtracting the number of lines for transmitting the error correction code from the number of lines, a correction code generation unit for generating an error correction code based on the divided data, and transmission data stored in a transmission buffer The storage amount is monitored, and when the transmission data accumulation amount becomes equal to or greater than a preset increase regulation value, one or more protection lines are connected, and the transmission data accumulation amount is set to a preset decrease regulation value. And a transmission control unit that performs cutting of the a value less than 1 or more lines of the protection line.

According to a third communication control device of the present invention, a communication line for performing data transfer includes one or more lines for transferring data and one or more lines for transferring an error correction code, and is always in a connected state. A transmission buffer which temporarily allocates transmission data and is allocated to a certain working line group and one or more protection line groups to be connected according to the data transfer amount, and the transmission data extracted from the transmission buffer is in a connected state. A data division unit for dividing the number of lines for transferring the error correction code from the number of communication lines, a correction code generation unit for generating an error correction code based on the divided data, the data division unit and the correction A line connection unit for transmitting the divided data and the error correction code received from the code generation unit to a communication line in a connected state and receiving data from the communication line in a connected state; A data combining unit that corrects data errors based on the divided data and the error correction code received from and combines the divided data as originally, and monitors the amount of transmission data stored in the transmission buffer, When the transmission data accumulation amount is equal to or more than a predetermined increase specified value, one or more protection lines are connected, and when the transmission data accumulation amount is equal to or less than a predetermined reduction specification value, one or more protection lines are connected. And a transmission control unit for disconnecting.

According to a fourth communication control device of the present invention, in the first, second, or third communication control device, the transmission data storage amount indicates a writing position when writing transmission data to the transmission buffer. The calculation is performed from a difference between a write pointer and a read pointer indicating a read position when reading transmission data from the transmission buffer.

According to a fifth communication control device of the present invention, in the first, second, or third communication control device, the number of the working lines and the number of the protection lines are respectively set in advance in correspondence with the date and time. The number of lines is changed according to a predetermined schedule table.

[0018]

Next, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram showing the connection of the system of the present invention. Referring to FIG. 1, a computer group A including a computer 10A, a communication control device 20A, and a LAN 30A connecting the computer 10A and the communication control device 20A.
, A computer group B including a computer 10B, a communication control device 20B, and a LAN 30B connecting these devices
And a line connecting the computer group A and the computer group B.

The computer group A and the computer group B are systems that execute processing while communicating with each other in the respective groups, and also frequently communicate with each other to execute processing. For example, in a form in which two business establishments in remote locations operate development and production in close relation, each business establishment has a computer group A and a computer group B.
Is installed.

Computer 10A and Computer 10B
Although three are shown in FIG. 1, the numbers do not need to be equal, and the number is not particularly limited. Also,
The computers 10A or 10B do not need to be of the same model, but may be connected to the LAN 30A or 30B and have a function of communicating with a common standard.

As shown in FIGS. 2 and 3, the communication control device 2
0A / 20B includes a transmission unit 40 for transmitting data received from the computers 10A / 10B, and a communication control device 20B.
/ 20A receives data from computer 10B / 10
A receiving unit 50 for providing to A, the transmitting unit 40 or the receiving unit 50
And line connection units 21 to 25 which are placed between the line and the line to transmit and receive data according to the line standard.

The line is not an expensive dedicated line, but a plurality of inexpensive general lines, and the number of lines is prepared such that the transfer can be performed according to the transfer amount that can be processed by the dedicated line. Among the general lines to be connected, the M (M is an integer of 2 or more) line is always used in a connected state (referred to as a regular line), and the remaining N (N is an integer of 1 or more) lines are used in accordance with the transfer amount. (Called a protection line). One or more of the M lines are used to transfer an error correction code added to transmission data.

Communication control device 20A and communication control device 20B
Need not be the same model, but hereafter, the communication control device 20A and the communication control device 20B are assumed to be the same for easy understanding. Also, regarding the number of general lines, M = 3,
In the following, it is assumed that N = 2 and one line is allocated to the transfer of the error correction code.

FIG. 2 is a block diagram showing the transmission section 40 of the communication control device 20A (the communication control device 20B is the same) in detail. The transmission unit 40 includes a transmission buffer 41 for temporarily storing transmission data to the computer group B received by the communication control device 20A from the computer 10A, a data division unit 42, a transmission control unit 43, and a correction code generation unit 44. .

The data division section 42 is a circuit for dividing the data in the transmission buffer 41 into a number according to the instruction of the transmission control section 43 and transmitting the transmission data to the line connection sections 21 to 24. The correction code generation unit 44 is a circuit that generates an error correction code based on the output data of the data division unit 42. The error correction code is defined based on, for example, the maximum number of lines including the working line and the protection line, and data of the unused protection line is treated as a fixed value (for example, “0”). The type and content of the error correction code are not particularly limited.

The transmission control unit 43 controls the transmission buffer 41 and the buffer control unit 45. The transmission control unit 43 observes a temporal change in the amount of transmission data held in the transmission buffer 41, and calculates the number of used backup lines based on the observation. The transmission amount monitoring unit 46 and the line connection units 21 to 25 based on the instruction of the transmission amount monitoring unit 46
A line connection control unit 47 for instructing (mainly 23 and 24) connection or disconnection of a line and a schedule table 48 in which the number of regular lines is set according to date and time, and control of the transmission unit 40 is executed. I do.

The buffer controller 45 includes a transmission buffer 41
Of the buffer, and controls writing and reading of the buffer. The transmission amount monitoring unit 46 monitors whether the difference between the write pointer 61 and the read pointer 62 is equal to or larger than a predetermined increase specified value or equal to or smaller than a specified decrease value. It requests the unit 47 to increase the number of lines, and requests the number of lines to decrease when the number of lines decreases below the prescribed value.

The transmission amount monitoring unit 46 may compare the difference between the write pointer 61 and the read pointer 49 at any time with a specified value. However, if the capacity of the transmission buffer 41 is not sufficiently large, the transmission buffer Since the ratio of the amount of data stored in the storage area 41 greatly fluctuates, in the present embodiment, the write pointer
8 and the average value of the difference between the read pointer 62 and
This average value is compared with a specified value.

When the line connection control unit 47 receives a request to increase the number of lines, it checks the state of the protection line, and if there is a connectable protection line, instructs to connect one protection line.
When a request to reduce the number of lines is received, it is checked whether or not a protection line is currently connected, and if there is a protection line currently connected, an instruction is given to disconnect one line. When the number of connections of the protection line changes, this result is reflected in the number of data divisions, and the data division unit 42
Is notified.

Although not shown, the line connection control unit 47 holds predetermined connection destination information (for example, address information such as a telephone number) for each of the line connection units 21 to 25, and outputs a connection instruction. At the time of connection destination information
Notify 25. Unless there is a special operation such as a failure process, the line connection units 21, 22, and 25 remain connected to connect to the regular line.

The line connection units 21 to 25 are connected to the communication control unit 2
It has an interface with a general line in 0A, and has a function of transmitting and receiving data based on the rule of the general line, and a function of connecting or disconnecting an actual line based on a line connection / disconnection instruction. When instructing line connection,
The connection destination information is provided from the line connection control unit 47.

FIG. 3 is a block diagram showing the receiving section 50 of the communication control device 20B (the same applies to the communication control device 20A). As shown in FIG. 3, the receiving unit 50 temporarily stores the received data received by the line connecting units 21 to 25 (same as that shown in FIG. 2), and the data buffer 51 which receives the divided data. And a reception buffer 58 for temporarily storing the received data after the data combination.

The data combining unit 56 includes a data buffer 51
５４54 and the error correction code of the data buffer 55 are synchronously fetched, an error is detected based on the fetched data and the error correction code, and an error detection and correction circuit 57 is operable to correct the error when there is an error. Are combined as before and output to the receiving buffer 58.

In FIG. 2 and FIG. 3, a line connection unit 21 and a line connection unit 22 are regular lines for transmitting and receiving data, and a line connection unit 23 and a line connection unit 24 are backup lines for transmitting and receiving data. The unit 25 is a regular line for transmitting and receiving the error correction code. The line connection units 21 to 25 are the transmission unit 4
0 and the receiving unit 50.

Next, the operation of the embodiment of the present invention will be described with reference to FIGS. Here, the operation of transmission from the computer group A to the computer group B will be described. Since the transmission in the reverse direction is the same, the description is omitted. In the initial state, it is assumed that the protection line is not connected, the transmission buffer 41 is empty, and both the write pointer 61 and the read pointer 62 are “0”.

For the sake of simplicity, it is assumed that the amount of transmission data per transmission is fixed,
It is assumed that the data transfer of 0A also matches the transmission data amount. However, it does not limit the amount of data to fixed,
Obviously, the present invention can be applied even if it is variable.

When the transmission data C is received from one of the computers 10A in this state, the communication control device 20A confirms that the transmission buffer 41 has a free space, and
Is written to the transmission buffer 41. When the transmission data C is written into the transmission buffer 41, the write pointer 61 of the buffer control unit 45 is incremented by 1 to “1”, and a difference from the read pointer 62 is generated.
No. 3 detects that the transmission data has been written.

Next, the transmission data C is divided into two and sent to the line connection unit 21, the line connection unit 22, and the correction code generation unit 44. The correction code generation unit 44 determines whether the transmission data C
, And sends the error correction code to the line connection unit 25.
The line connection units 21, 22, 25 divide and transmit the transmission data C to the communication control device 20B of the connection destination through the general line.

When the transmission of the transmission data C is completed, the buffer controller 45 increments the read pointer 62 by "1".
And put the next transmission data in a state of being taken out. On this occasion,
If the communication control device 20A has already received the transmission data D and E following the transmission data C, the write pointer 61
Is +3 compared to the beginning to be “3”, and is in a state of +2 with respect to the read pointer 62, so that the transmission data D and E are continuously transmitted to the communication control device 20B by 2 in the same procedure as described above. Divide and send.

The communication control unit 20B transmits transmission data C, D, and E divided by two to the line connection units 21, 22, 2,
5, the data is temporarily stored in the data buffers 51, 52 and 55. Next, the data combining unit 56 transmits the transmission data C divided into two from the connected data buffers 51, 52, and 55.
Is detected, and it is detected whether or not there is an error between the data portion and the error correction code. If an error is detected, the error is corrected,
Combine the divided data as before.

Next, the combined transmission data C is written into the reception buffer 58, and is temporarily stored in the reception buffer 58. Similarly, the transmission data D and E are combined with the original data and written into the reception buffer 58. Receive buffer 5
8 is transferred to the destination computer 10B via the LAN 30B.

Next, a case will be described in which a large amount of transmission data is concentrated from the computer 10A, and the transmission buffer 41 accumulates data of a specified value or more. The specified value of the increase is not particularly limited, but here, 3/4 (75%)
Is the specified increase value. For example, if the maximum value of the write pointer 61 and the read pointer 62 is “16”, the difference between the pointers = “12” becomes the specified increase value. The increase specified value is
The number of computers 10A connected to the LAN 30A,
The optimum value may be set in consideration of the environment such as the transfer performance of the LAN 30A and the communication control device 20A, the performance of the general line, the number of lines, and the operation content, and based on the results.

When the amount of data held in the transmission buffer 41 exceeds the specified increase value, the transmission amount monitoring unit 46 detects this and requests the line connection control unit 47 to increase the line. Upon receiving the increase request, the line connection control unit 47 checks whether there is an unconnected spare line, detects that the line connection unit 23 is not connected, refers to the connection destination information, and makes the line connection unit 23 Instruct the connection control unit 20B to connect to the line connection unit 23.

The line connection unit 23 of the communication control device 20A
The connection procedure determined by the general line is executed to the line connection unit 23 of the communication control device 20B to connect the line. When the line is connected, the transmission control unit 43 increases the number of divisions of the transmission data by one to “3” and sets this to “3”.
Notify 2.

After the transmission buffer 4 has been divided into three parts,
The transmission data read from 1 is divided by the data division section 42 into 3
The data is divided and sent to the line connection units 21, 22 and 23, and an error correction code is generated by the correction code generation unit 44 for the data divided into three in parallel, and sent to the line connection unit 25.
Communication control device 2 from line connection units 21, 22, 23, 25
The data divided into three into 0B and the error correction code are transmitted.

Thereafter, the communication control device 20A is connected to the computer 1
The transmission data received from 0A is transmitted after being divided into three parts. Further, the transmission amount monitoring unit 46 monitors the amount of data stored in the transmission buffer 41 after a certain period of time, and if the amount is less than the specified increase value and larger than the specified decrease value, the transmission is continued in a three-part state.

At the time of monitoring after a certain time, the transmission buffer 41
When the accumulated data amount again becomes equal to or more than the specified increase value, the transmission amount monitoring unit 46 detects this and instructs the line connection unit 24 to connect the line in order to connect the unconnected protection line. I do. The line connection unit 24 connects the line with the communication control device 20B as described above, and when the connection state is established, the transmission control unit 43 increases the number of divisions of the transmission data by one to “4”.
This is notified to the data division unit 42.

After the transmission buffer 4 has been divided into four parts,
The transmission data read from 1 is divided into 4
The data is divided and sent to the line connection units 21, 22, 23 and 24, and an error correction code is generated by the correction code generation unit 44 for the data divided in four in parallel, and sent to the line connection unit 25. The data divided into four and the error correction code are transmitted from the line connection units 21, 22, 23, 24, 25 to the communication control device 20B.

Even if the amount of data stored in the transmission buffer 41 again becomes equal to or more than the specified increase value in the four-partitioned state, the protection lines cannot be increased because the protection lines are all connected. The unit 46 maintains the connection state as it is. When the transmission buffer 41 becomes full and becomes unacceptable, the transmission control unit 43 refuses to accept transmission data from the computer 10A until the transmission buffer 41 becomes available.

Next, a case where the amount of data transmitted from the computer 10A decreases and the amount of data stored in the transmission buffer 41 becomes equal to or less than the prescribed decrease value will be described. Although there is no particular limitation on the value of the prescribed decrease value, here, 1/4 (25
%) Is defined as the decrease specified value. For example, write pointer 61
If the maximum value of the read pointer 62 is set to "16", the difference between the pointers = "4" becomes the specified decrease value. Similarly to the increase prescribed value, the decrease prescribed value may be set to an optimal value based on the system configuration, the operating environment, and the results.

When the amount of data stored in the transmission buffer 41 becomes equal to or less than the prescribed decrease value in the state of division into three, the transmission amount monitoring unit 46 detects this and disconnects the protection line to be connected. It instructs the line connection unit 23 to disconnect the line. The line connection unit 23 of the communication control device 20A executes a disconnection procedure defined for a general line with respect to the line connection unit 23 of the communication control device 20B, and disconnects the line. When the line is not connected, the transmission control unit 43 reduces the number of divisions of the transmission data by one to “2” and sets this to “2”.
Notify to Thereafter, as in the beginning, the transmission data is divided into two and transmitted.

When the amount of data stored in the transmission buffer 41 becomes equal to or less than the prescribed decrease value in the state of division into four, similarly to the case of division into three, one of the connected protection lines is disconnected and the state of division into three is established. change. If the amount of data stored in the transmission buffer 41 becomes equal to or smaller than the prescribed decrease value in the two-partition state, there is no spare line being connected, and the state is maintained as it is.

As described above, since the number of connection lines is increased or decreased according to the amount of data transferred, unnecessary line usage fees caused by keeping the connection in an unused state can be reduced. . In addition, since a line that is always connected and a line that connects / disconnects according to the transfer amount are provided, if the transfer rate is within the transfer rate of the regular line, there will be a waiting time for connecting a new line. Can be avoided, and the overhead associated with connecting / disconnecting the line can be reduced.

Further, since the error correction code is transferred to the divided data on another line independent of the data transfer line, the data and the error correction code are transferred on the same line. In addition, it is possible to prevent the data and the error correction code from being invalid at the same time due to the failure of the line, thereby making it impossible to correct the error. Therefore, a data error can be corrected with a higher probability, and the reliability of the system is improved.

In the above description, the case where M = 3 and N = 2 has been described, but it is clear that the present invention can be easily implemented in other cases. Although there is no particular restriction on the method of generating the error correction code, the error correction code has a large ratio to the data of the error correction code when the amount of data to be processed is small, that is, the ratio of the data delayed per line. Although the efficiency becomes lower as the size becomes smaller, the ratio becomes smaller and the efficiency becomes better as the data amount to be processed becomes larger.

Therefore, when the number of lines is small, when the K-divided data is arranged side by side, each is divided into L in the vertical direction with an appropriate size, and an error correction code is added for each division in the vertical direction. , L error correction codes are transmitted together with the transfer data.

On the other hand, when the number of lines is large, for example, M =
In the case of 32 + 8 and N = 32, if 8 lines are allocated as error correction codes, a 1-bit error correction code can be added to each 1-bit transfer of each line. Can be corrected, and the reliability is improved more efficiently. This becomes more remarkable as the number of lines increases. At this time, although not shown, a circuit for dividing the 8 bits generated by the correction code generation unit 44 into eight lines may be added.

The number of service lines and the number of protection lines may be determined according to the operation status of the system.
If about 0% of the line is used, 70% + α may be used as the regular line.

In an operation state in which the use status of the line has a remarkable tendency with respect to the date and time, the number of regular lines can be switched using the schedule table 48 for operation.
For example, if the usage is low on holidays and holidays, and the business is concentrated on the weekend and the usage is high, create a schedule that reduces the number of regular lines on holidays and holidays and increases it only on weekends. I just need.

Here, the schedule table may record the date and time and the number of regular lines as a pair. The date and time may be specified as a day of the week, specified as a day in a month, or specified as a month end. May be. For example, every Friday 1
From 3:00 to 17:00, M = 30, N = 10, M = 10, N = 30 for holidays and public holidays, and M =
20, a schedule table is created so that N = 20.

As described above, by changing the number of regular lines according to the state of use, communication becomes smoother.
Costs can be saved at times of low usage. Also, the unit of the number of lines newly connected or disconnected is not limited to one line, and control may be performed in units of two or more lines. In particular, when the number of lines is large, it is effective to perform control in a unit to reduce overhead caused by connection / disconnection of lines.

[0062]

The first effect is that the quality of a line with low reliability can be improved. The reason is that a line for transferring an error correction code added to data and a line for transferring data are provided independently, and the data is divided into a plurality of lines.

The second effect is that the line use cost can be reduced. The reason is that the number of lines used can be switched during operation according to the line usage rate.

The third effect is that if the transfer amount is up to a preset transfer amount, it is possible to avoid waiting for a time for additionally connecting a line.
This is to reduce overhead generated by frequently connecting and disconnecting lines. The reason is that, since a regular line that is always connected and a spare line that is connected / disconnected according to the transfer amount are provided, data transfer can be performed only with the normal line up to a preset transfer amount.

The fourth effect is that when the operation load is periodically or regularly biased, the cost can be further reduced by changing the number of service lines according to a predetermined schedule.

[Brief description of the drawings]

FIG. 1 is a block diagram showing connection of a system according to an embodiment of the present invention.

FIG. 2 is a communication control device 20A / 2 according to the embodiment of the present invention.
0B transmitter

FIG. 3 is a communication control device 20A / 2 according to the embodiment of the present invention.
0B receiver

[Explanation of symbols]

 10A computer 10B computer 20A communication control device 20B communication control device 21 line connection unit 22 line connection unit 23 line connection unit 24 line connection unit 25 line connection unit 30A LAN 30B LAN 40 transmission unit 41 transmission buffer 42 data division unit 43 transmission control unit 44 Correction code generation unit 45 Buffer control unit 46 Transmission amount monitoring unit 47 Line connection control unit 48 Schedule table 50 Receiving unit 56 Data combining unit 57 Error detection and correction circuit 58 Receiving buffer 61 Write pointer 62 Read pointer

Claims (11)

[Claims] 1. A communication system for transferring data from a communication control device A to a communication control device B via a communication line, wherein the communication line includes a group of two or more regular lines which are always connected, and a data transfer amount. The communication system comprises one or more lines for transferring data and the one or more lines for transmitting error correction codes. . 2. A communication system for transferring data from a communication control device A to a communication control device B via a communication line, wherein the communication line includes one or more lines for transferring data and one or more lines for transferring an error correction code. 1 is connected in accordance with the amount of data transferred to a group of regular lines which are always in a connected state.
Communication control unit A
Has a transmission buffer for temporarily storing transmission data, monitors a transmission data accumulation amount accumulated in the transmission buffer, and, when the transmission data accumulation amount becomes equal to or more than a predetermined increase specified value, one line or more. Connect the backup line of
A communication system characterized in that one or more protection lines are disconnected when the transmission data storage amount becomes equal to or less than a predetermined reduction value. 3. A communication system for transferring data from a communication control device A to a communication control device B via a communication line, wherein the communication line includes one or more lines for transferring data and one or more lines for transferring an error correction code. 1 is connected in accordance with the amount of data transferred to a group of regular lines which are always in a connected state.
Communication control unit A
A transmission buffer that temporarily holds transmission data, and a data division unit that divides the data extracted from the transmission buffer into a number obtained by subtracting the number of lines for transferring the error correction code from the number of communication lines in the connected state, A correction code generation unit that generates an error correction code based on the divided data, monitors a transmission data accumulation amount accumulated in a transmission buffer, and the transmission data accumulation amount is equal to or greater than a predetermined increase specified value. A communication line for connecting one or more protection lines, and disconnecting one or more protection lines when the transmission data storage amount becomes equal to or less than a predetermined decrease specified value. 4. Communication for transferring data from a computer group A including one or more computers A and a communication control device A to a computer group B including one or more computers B and a communication control device B via a communication line. In the system, the communication line includes one or more lines for transferring data and one or more lines for transferring an error correction code, and a group of regular lines that are always connected, and one line that is connected according to a data transfer amount. The communication control device A, comprising
Is a transmission buffer for temporarily storing transmission data received from the computer A, and a number obtained by subtracting the number of transmission lines for transmitting the error correction code from the number of communication lines in a connected state for the transmission data extracted from the transmission buffer. A data division unit for dividing, a correction code generation unit for generating an error correction code based on the divided data, and a connection state between the divided data and the error correction code received from the data division unit and the correction code generation unit. The communication control device B corrects the data error based on the divided data and the error correction code received from the communication line in the connected state, and divides the data. The communication control unit A monitors the amount of transmission data stored in the transmission buffer, and stores the transmission data in the transmission buffer. When the product amount is equal to or greater than a predetermined increase specified value, one or more protection lines are connected, and when the transmission data accumulation amount is equal to or less than a predetermined reduction value, one or more protection lines are disconnected. A communication method characterized by that: 5. The transmission data storage amount includes a write pointer indicating a write position when writing transmission data to the transmission buffer and a read pointer indicating a read position when reading transmission data from the transmission buffer. 5. The communication method according to claim 2, wherein the difference is calculated from a difference between the two. 6. The system according to claim 2, wherein the number of the service lines and the number of the backup lines are changed in accordance with a schedule table in which the number of each line is determined in advance in accordance with the date and time. Communication method. 7. A communication line group for constantly transferring data comprising one or more lines for transferring data and one or more lines for transferring an error correction code, and a data transfer amount. And a transmission buffer for temporarily storing transmission data, and monitoring a transmission data accumulation amount accumulated in the transmission buffer, and setting the transmission data accumulation amount in advance. A transmission control unit for connecting one or more spare lines when the set increase value is equal to or more than a predetermined increase value and disconnecting one or more protection lines when the transmission data storage amount is equal to or less than a preset decrease value; A communication control device having: A communication line for performing data transfer is composed of one or more lines for transferring data and one or more lines for transferring an error correction code, and a group of regular lines in a constantly connected state, and a data transfer amount. Is assigned to one or more spare lines connected according to the transmission buffer, and an error correction code is transferred from the transmission buffer for temporarily holding the transmission data and the number of communication lines in which the data extracted from the transmission buffer is connected. A data division unit that divides the number of lines into a number, a correction code generation unit that generates an error correction code based on the divided data, and monitors the amount of transmission data stored in a transmission buffer, and When the storage amount becomes equal to or more than a predetermined increase specified value, one or more protection lines are connected, and when the transmission data storage amount becomes equal to or less than a predetermined decrease specified value, one or more protection lines are connected. A communication control device having a transmission control unit for disconnecting a service line. 9. A communication line for performing data transfer, comprising: one or more lines for transferring data and one or more lines for transferring an error correction code; And a transmission buffer for temporarily storing transmission data, and transmitting an error correction code from the number of communication lines connected to the transmission data extracted from the transmission buffer. A data division unit that divides the number of lines to be divided into a number of lines, a correction code generation unit that generates an error correction code based on the divided data, and the divided data received from the data division unit and the correction code generation unit. A line connection unit for transmitting data and an error correction code to the connected communication line and receiving data from the connected communication line; and a divided data received from the line connection unit. A data combining unit that corrects the data error based on the data and the error correction code and combines the divided data as before, and monitors the amount of transmission data accumulated in the transmission buffer, and A transmission control unit that connects one or more protection lines when the transmission data amount becomes equal to or more than a predetermined increase specified value, and disconnects one or more protection lines when the transmission data storage amount becomes equal to or less than a predetermined reduction specification value. A communication control device having: 10. The transmission data storage amount includes a write pointer indicating a write position when writing transmission data to the transmission buffer and a read pointer indicating a read position when reading transmission data from the transmission buffer. The communication control device according to claim 7, 8 or 9, wherein the communication control device calculates the difference based on a difference between the two. 11. The system according to claim 7, wherein the number of the regular lines and the number of the backup lines are changed according to a schedule table in which the number of the respective lines is determined in advance according to the date and time. Communication control device.