JPH0490230A - Access control system for communication network - Google Patents

Abstract

PURPOSE:To reduce the scale of a master station, and to attain efficient communication by changing the allocation of a slave station in response to a data quantity of the slave station by the control of the slave station. CONSTITUTION:A master station 10 receives a signal from a slave station 20 and when an access request detection section 1 of the master station 10 detects a transmission request from the slave station 20, the slave station number is stored. Then a transmission enable is sent to the slave station 20 whose 'presence of transmission request' is stored with priority. The slave station 20 receives the transmission enable from the master station 10 and a consecutive access request storage section 5 stores a consecutive transmission request when a data consecutive transmission request is in existence, and the transmission from other station is suppressed in the transmission line by the transmission request signal from the slave station 20 and the consecutive access request is stored in the consecutive access request storage section 5, the transmission request signal from an access request transmission section 4 is suppressed to control the transmission line so as to be occupied by the slave station 20 by the control from the slave station 20 then the efficient data transfer is implemented.

Description

[Detailed Description of the Invention] [Summary] Between a master station and a plurality of slave stations connected to the master station, the master station gives transmission rights to the slave stations, and the slave stations use the transmission rights to transfer data to the master station. An access control method for communication networks that enables efficient data communication between the master station and slave stations by distributing control to slave stations and controlling small-scale master stations and slave stations. The main station includes an access request detection unit that detects a transmission request from a slave station, a selection control unit that grants transmission rights to a slave station that has made a transmission request from the output of the access request detection unit, and a transmission A transmission right granting unit is provided that controls the transmission right to be granted cyclically when there is no request, and the slave station has an access request sending unit that sends a transmission request to the master station, and stores whether or not there is a request to continue data transmission. A continuous access request storage unit is provided, and the slave station receives a transmission permission signal from the master station, and sends a transmission request signal when requesting continuous transmission of data, and the transmission path is connected to other stations by the transmission request signal from the own station. When the transmission from the access request sending section is suppressed and the continuous access request is stored in the continuous access request storage section, the transmission request signal from the access request sending section is suppressed.

[Industrial application field]

The present invention provides an access control method for a communication network between a master station and a plurality of slave stations connected to the master station, in which the master station grants transmission rights to the slave stations, and the slave stations use the transmission rights to transmit data to the master station. Regarding.

In recent years, with the development of information processing equipment, the demand for communication between information processing equipment has increased.

For this reason, there is a need for a method for efficiently communicating between a plurality of information processing devices by using one set of communication paths.

Therefore, if one of the information processing devices is the master station and the other information processing devices are the slave stations, and the master station centrally controls the entire communication path, many information processing devices can be connected to one set of communication paths. too,
Communication can be performed without loss of information due to congestion.

In particular, in 15DN etc., network terminal equipment (NT; N
A plurality of communication terminal devices (TE; Terminal Equip)
ment) and one-to-many communication with different transmission speeds, such as voice and image, requires an efficient access method.

[Conventional technology]

FIG. 9 is a diagram illustrating the hardware configuration of a conventional main station.

The operation of the conventional example will be explained using the operation of the main station 10a in FIG.

In the figure, IIA is a multiplexer (indicated as MUX in the figure)
, 12A is a selector (indicated by SEL in the figure), 13A is a requested slave station number register (indicated by TENOr REG in the figure), and 13B is a non-required slave station number register (indicated by TENOp in the figure).
13C is a request table (indicated as REQ TABLE in the figure), 16A is a distribution device (
DMUX in the figure), 17a is a control circuit (C0N in the figure
18a is a counter (denoted as CNT in the figure).

In the configuration described above, uplink data is distributed to the distribution device 1.
6A, slave station number TENO1 request bit R and slave station 20
Transmission data DATA from a (not shown) to the main station 10a
The data DATA is transferred to a data processing unit (not shown) in the main station 10a, and sent to the slave station number TENO.
is applied as an address signal to the request table 13C, and the request bit R becomes data written to the request table 13C.

In other words, the request table 13c includes a plurality of slave stations 2
It consists of a register having the number of bits corresponding to 0a, and each bit indicates whether or not the corresponding plurality of slave stations 20a have a continuous transmission request (whether or not they have transmitted a continuous transmission request).

The request slave station number register 13A contains the controller 17a.
, the contents of the request table 13C become "1".
” (indicating that there is a continuous transmission request),
One slave station number is held in a circular order, and the contents of this request slave station number register 13A are the slave station 20 indicated by the contents.
Every time a connection is made to a, the content of the request table 13C is updated to the next number in a cyclical order among the slave station numbers that are "1".

The controller 17 is stored in the non-request slave station number register 13B.
Under the control of a, the contents of the request table 13C are changed to “
0'' (indicating that there is no continuous transmission request), one slave station number is held in a circular order, and the contents of this non-request slave station number register 13B indicate whether the slave station 20a is connected to the slave station 20a indicating the content or not. Every time it is done, the request table 13
Among the slave station numbers for which the content of C is "0", the number is updated to the number of the next slave station 20a in a cyclical order.

The counter 18a continuously counts the requested slave station number register 13.
The number of times a connection is made to the slave station indicated by A is counted.

The control circuit 17a holds at least one rN in the request table 13C, and the counter 18
When the count value of a is less than a predetermined number, the selector 12A is controlled to connect to the slave station 20a indicated by the request slave station number register 13A, and when no "l" is held in the request table 13C, Alternatively, when the count value of the counter 18a becomes equal to a predetermined number, the selector 12A is controlled to connect to the slave station 20a indicated by the non-request slave station number register 13B.

[Problem to be solved by the invention]

In the case of the conventional example shown in FIG. 9 described above, the transmission request of the slave station 20a is stored in the request table 13C of the master station 10a, and in order to control so that a particular slave station 20a does not occupy the transmission path. The counter 18a counts the number of connections, and when the specified number of connections is reached, the control circuit 17a controls the slave station 20a to disconnect. Put it away.

The present invention aims to provide an access control method for a communication network that can efficiently transfer data between a master station and a slave station by distributing control to slave stations and controlling a small-scale master station. purpose.

[Means to solve the problem]

FIG. 1 shows a detailed diagram of the invention.

In the block diagram of the principle of the present invention shown in FIG. 1, 10 is a main station, 1 is an access request detection section that detects a transmission request from the slave station 20, and 2 is an output of the access request detection section 1. A selection control section 3 gives a transmission right to a slave station 20 that has made a transmission request, and 3 is a transmission right granting section that controls to cyclically give a transmission right when there is no transmission request.

Further, 20 is a slave station, 4 is an access request sending unit that sends a transmission request to the main station 10, 5 is a continuous access request storage unit that stores the presence or absence of a continuous transmission request, and the slave station 20 is the main station. When receiving a transmission permission signal from the station 10 and requesting continued transmission of data, transmitting a transmission request signal;
This problem is solved by suppressing the transmission request signal from the access request sending unit 4 when the transmission path is suppressed from transmission from other stations by the transmission request signal from the own station and a continuous access request is stored. It will be used as a means to achieve this goal.

[For production]

The master station 10 receives a signal from the slave station 20, and when the access request detection unit 1 detects a transmission request from the slave station 10, it stores the slave station number.

Thereafter, a transmission permission is sent preferentially to the slave station 10 that has stored that "there is a transmission request".

In addition, at other times, transmission permission is cyclically given to slave stations 20 that are not stored as having a "transmission request".

The slave station 20 receives a transmission permission from the master station IO, and if there is a request for continuous data transmission, stores the continuous transmission request in the continuous access request storage section 5, and transmits the request via the transmission path or by a transmission request signal from one slave station 20. When transmission from other stations is suppressed and the continuous access request is stored in the continuous access request storage unit 5, by suppressing the transmission request signal from the access request sending unit 4, the transmission is controlled by the slave station 20. road 1
It is possible to perform control so that the slave station 20 is not occupied by one slave station 20, and to perform efficient data transfer.

〔Example〕

The gist of the present invention will be specifically explained below with reference to embodiments shown in FIGS. 2 to 8.

FIG. 2 is a diagram explaining the configuration of the main station in the embodiment of the present invention, FIG. 3 is a diagram explaining the configuration of the slave station in the embodiment of the present invention, and FIG.
The figure is a diagram explaining the hardware configuration of the master station in the embodiment of the present invention, FIG. 5 is a diagram explaining the hardware configuration of the slave station in the embodiment of the present invention, and FIG. 6 is the embodiment of the present invention. 7 is a diagram illustrating a flowchart of the operation of the master station in the embodiment of the present invention, FIG. 8 is a diagram illustrating the communication format of the embodiment of the present invention. Note that the same reference numerals indicate the same objects throughout the figures.

In the configuration of the main station 10 according to the embodiment of the present invention shown in FIG. 2, 11 is a transmitter, 12 is a selector, 13 is a control circuit, 1
4 is a polling table, 15 is a FIFO memory, 16
is the receiving section.

The format of data transmitted from slave station 20 is shown in FIG.

The down line signal is the slave station number TENO and data (DAT in the figure).
A), and the uplink signal is the slave station number TENO.
, request bit R, and data.

The master station 10 receives the uplink signal shown in FIG. 8 from the slave station 20, and transmits the received signal to the slave station number T
It is separated into ENO and request bit R and sent to the FIFO memory 15.

If the request bit R exists, the FIFO memory 15 reads the slave station number TENO and notifies the control circuit 13 that a transmission request has been received.

The control circuit 13 stores the slave station number TENO in the FIFO memory 15.
If there is, the FIFO takes priority over the polling table 14.
The slave station number TENO in the memory 15 is selected by the selector I2 and sent to the transmitter II, and at other times the slave station number TENO is selected by the selector 12 according to the polling table 14.
, and sends it to the transmitter 11.

The transmitter 11 uses this slave station number TENO to transmit the slave station 20.
access.

In the configuration of the slave station 20 according to the embodiment of the present invention shown in FIG. 3, 2I is a reception section, 22 is a transmission section, 23 is a slave station number holding section, 24 is a control circuit, 25 is a request generation section, and 26 is a FIFO memory. It is.

The slave station 20 which has obtained the transmission right from the master station 10 separates the slave station number TENO from the received signal in the receiving section 21.

If the slave station number TEN from the receiving unit 21 matches the own slave station number TENO, and if the number of consecutive transmission requests is less than a certain value and the amount of data from the FIFO memory 26 cannot be transmitted at once, the control circuit 24 will not transmit data yet. A request generating section 25 generates a transmission request to notify the main station 10 that the desired data remains, and a signal is generated at the transmitting section 22 and sent to the main station 10.

In other cases, the request generation unit 25 does not generate a transmission request, and the transmission unit 22 generates a signal indicating that there is no request and sends it to the main station 10.

4 and 5 show specific examples of the hardware configurations of the master station 10 of FIG. 2 and the slave station 20 of FIG. 3, respectively.

In the configuration shown in FIG. 4, IIA is a multiplexer, 12A is a selector, 13A is a requesting slave station number register, 13B is a non-requesting slave station number register, 13C is a request table, 1
6A is a distribution device.

A signal sent from the slave station 20 through the up line is separated into a slave station number TENO and a request bit R by the distribution device 16A.

The request table 13C has an address corresponding to the slave station 20. If the request bit R is "0", write rOJ to the address corresponding to the slave station number TENO, and if the request bit R or "IJ", write rOJ to the address corresponding to the slave station number TENO.
Write "1" to the address corresponding to .

Request slave station number register 13A is request table 13
C indicates the address of "1", and each time it is selected, the next "1"
” is stored.

Further, the non-request slave station number register 13B indicates the address of "0" in the request table 13C, and each time it is selected, it indicates the address storing the next "0".

When transmitting data to the slave station 20, the selector 12A selects the slave station number TENO indicated by the request slave number register 13A if there is a slave station number TENO indicating that a transmission request has been generated in the request slave station number register 13A, and selects the slave station number TENO indicated by the request slave station number register 13A. If there is no slave station number TENO indicated by the register 13A, the slave station number TENO indicated by the non-request slave station number register 13B is selected.

In the multiplexer 11A, a signal is synthesized from the slave station number TENO and the data, and is transmitted to the slave station 20 via the downlink.

In the configuration shown in FIG. 5, 21A is a distribution device, 22A is a multiplexing device, 23 is a slave station number holding unit, 24A is a counter,
26A is a data buffer (indicated as D-BUFF in the figure);
27A is a comparison circuit (indicated as CMP in the figure).

The signal passing through the down line from the main station 10 is transmitted to the distribution device 2.
1A separates the slave station number TENO and data.

Slave station number TENO and slave station IO separated by comparison circuit 27A
The slave station number TEN that it owns in the slave station number holding unit 23
0 and identifies whether the signal is for this slave station or not.

If the slave station numbers TENO match, this slave station is being accessed, so the data buffer 26A storing data is opened and as much data as is transmitted each time is taken out.

At this time, after extracting the data, data buffer 2
If there is any data remaining in 6, the request bit R is set to "1", and if no data remains, the request bit R is set to "0" and the data is sent to the counter 24A.

The counter 24A counts up when the request bit R or rlJ is present, and clears the count when the request bit R is "0".

When data transmission requests continue for a certain value or more, that is, when the counter 24A continues to count up and the count value reaches a certain certain value or more, even if the request bit R is "1", the request bit R is set to "1". 0'' and there is no transmission request, and the transmission right is delegated to another slave station.

After this, in the multiplexer 22A, the slave station number TENO,
This is a flowchart showing the operation of generating a signal based on data and request bit R.

With the configuration described above, by controlling the transmission of continuous transmission requests by the slave station 20, the functions of the master station 10 can be distributed to the slave stations 20, and the scale of the master station 10 can be reduced.

〔Effect of the invention〕

According to the present invention as described above, the assignment of the slave stations can be changed according to the amount of data of the slave stations by controlling the slave stations, the scale of the master station can be reduced, and communication can be performed efficiently.

[Brief explanation of the drawing]

FIG. 1 is a block diagram explaining the present invention in detail, FIG. 2 is a diagram explaining the configuration of a master station according to an embodiment of the present invention, and FIG. 3 is a diagram explaining the configuration of a slave station according to an embodiment of the present invention. , FIG. 4 is a diagram explaining the hardware configuration of the master station in the embodiment of the present invention, FIG. 5 is a diagram explaining the hardware configuration of the slave station in the embodiment of the present invention, and FIG. 6 is a diagram explaining the hardware configuration of the slave station in the embodiment of the present invention. FIG. 7 is a diagram explaining the operation flowchart of the slave station according to the embodiment of the present invention. FIG. 8 is a diagram explaining the communication format of the embodiment of the present invention. The figures are a diagram explaining the hardware configuration of a conventional main station. In the figure, 1 is an access request detection unit, 2 is a selection control unit, 3 is a transmission right granting unit, 4 is an access request sending unit, 5 is a continuous access request storage unit, 10.10a is a master station, 20 is a slave station, and IL22 11A, 22A are multiplexers, 12.12A are selectors, 13.17a, 24 are control circuits, 13A is requested slave station number register, 13B is non-required slave station number register, 13C is request table, 14 is polling table, 15.26 is FIFO memory, 16.21 is receiving section, 16A, 21A are distribution devices, 18a, 24A are counters, 23 is slave station number holding section, 25 is request generation section, 26A is data buffer, 27A is comparison The circuits and are shown respectively. Figure 1 is a block diagram explaining the detailed explanation of the present invention. Figure 2 is a block diagram explaining the configuration of the slave station of the present invention. Figure 5 is explaining the hardware configuration of the slave station of the embodiment of the present invention. 1ii(?lJ) Figure 5 illustrating the operational flow of one station according to the embodiment of the present invention. 4.Explain -I-4
Logz n (n; maximum number of slave stations)
R: 1 bit DATA, data FIG. 8 is a diagram explaining the communication format of the embodiment of the present invention.

Claims (3)

[Claims] (1) Between a master station (10) and a plurality of slave stations (20) connected to the master station (10), the master station (10) grants transmission rights to the slave stations (20), and the slave stations (20) is an access control method for a communication network that transmits data to the master station (10) using the transmission right, and includes access request detection for detecting a transmission request from the slave station (20) to the master station (10). a selection control unit (2) that, based on the output of the access request detection unit (1), grants a transmission right to the slave station (20) that has received a transmission request; A transmission right granting unit (3) for controlling the granting of transmission rights is provided, and the slave station (20)
is provided with an access request sending unit (4) that sends a transmission request to the master station (10), and a continuous access request storage unit (5) that stores whether or not there is a request for continuation of data transmission, and the slave station (20) ) sends a transmission request signal when requesting continuous transmission of data when receiving the transmission permission signal from the main station (10), and the transmission path is connected to the transmission request signal from the other station by the transmission request signal from the own station. Access to a communication network, characterized in that when transmission is suppressed and a continuous access request is stored in the continuous access request storage unit (5), a transmission request signal from the access request sending unit (4) is suppressed. control method. (2) When the slave station (20) receives a transmission permission signal from the master station (10) and requests continuous transmission of data, if the number of continuous data transmission requests is less than a predetermined value,
Claim (1) characterized in that a transmission request signal is transmitted.
Access control method for the communication network described. (3) When the slave station (20) receives a transmission permission signal from the master station (10) and requests continuous transmission of data, if the number of continuous data transmission requests is equal to or greater than a predetermined value,
Claim (1) characterized in that the transmission request signal is not transmitted.
) Communication network access control method described in ).