JPH0637775A - Token controller - Google Patents

Abstract

(57) [Summary] [Purpose] A talk ring in which multiple tokens orbit,
Limit the number of tokens acquired in one cycle of the transmission frame according to the priority of the station to improve the utilization efficiency of the transmission area,
Also, a token control device that shortens the total data transmission time is obtained. [Configuration] Control information area monitoring means for monitoring the setting information from the master station and setting the number of tokens of the designated own station,
At the time of data transmission, the counter / token acquisition control means is provided for referencing the set number of tokens of the own station and controlling the acquisition of empty tokens in the same transmission frame up to the number of tokens of the own station referred to above.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transmission control method for a loop type network, and more particularly to a system in which a plurality of tokens circulates throughout a token ring (hereinafter referred to as a multi-token system).

[0002]

2. Description of the Related Art FIG. 7 shows, for example, Japanese Patent Laid-Open No. 63-24014.
This is a configuration of a token ring according to the conventional multi-token system shown in Japanese Patent No. 8 publication. In FIG. 7, a plurality of stations 70a to 70n and the like 70 are connected in a loop via a transmission line 71, and one of them, for example, 70a, becomes a master station. Reference numeral 72 is a transmission frame that circulates on the transmission path in the direction indicated by the arrow. This transmission frame 72 is composed of a synchronization pattern 74 located at the beginning and n transmission areas 75, 76 and 77 following the synchronization pattern 74.
One token 73 is assigned to each of the transmission areas 75, 76, 77, and a plurality of tokens circulate on the ring at the same time.

FIG. 8 is a transmission control block diagram of only the transmission section of a conventional station. In the figure, 1 is a transmission path, 82 is a token acquisition control unit, 3 is a data packet transmission completion control unit, 84 is a data packet transmission control unit, 5
Is a read circuit, 86 is a transmission buffer, 87 is a transmission request unit, and 8 is a CP connected to the transmission unit via an internal bus 90.
U, 9 and 10 are selectors, 91 is a data packet transmission permission signal, 92 is a relative number, 93 is a token transmission request signal, and 94 is a transmission request signal.

Next, the data transmission operation in the station will be described. The station 70, which has prepared the data packet to be transmitted, first stores the data packet in the transmission buffer 86, and the transmission buffer 86 notifies the transmission request unit 87 that the transmission packet is ready for transmission. In response to this, the transmission request unit 87 sends a transmission request 94 to the token acquisition control unit 82. In response to the transmission request 94, the token acquisition control unit 82 sequentially monitors the respective transmission areas 75, 76, 77 in the transmission frame 72 passing through the station 70, and acquires the first detected token 73. If acquired, the position (relative number) occupied by the data packet transmission permission signal 91 and the transmission area including the token 73 on the transmission frame 72 to the data packet transmission control unit 84 and the data packet transmission completion control unit 3 Notify 92. After that, the data packet transmission control unit 84 operates the read circuit 5 and the selector 10 at a predetermined timing, and transmits the data packet in the transmission buffer 86 on the transmission path by using the notified transmission area.

During the time that a data packet is being transmitted,
The data packet transmission completion control unit 3 monitors the transmission area notified by the token acquisition control unit 82, and detects the ending delimiter of the data packet and the response information of the data packet that follows. When detected, the data packet transmission completion control unit 3 notifies the transmission request unit 87 of the transmission completion. Further, the token acquisition control unit 82 is notified of the token transmission request 93, and in response to this, the token acquisition control unit 82 operates the selector 9 to place the token 73 in the transmission area where data has been transmitted until now. The data is transmitted, and the data transmission operation ends.

In the conventional multi-token system as described above, when a station sends data, the transmission frame circulating on the transmission path is divided into a plurality of transmission areas and the tokens are allocated to the respective transmission areas. The station can usually obtain only one token, and can occupy only one transmission area among the plurality of transmission areas. Therefore, the amount of data that can be sent in one cycle of the transmission frame is limited. This becomes more remarkable as the number of transmission areas obtained by dividing the transmission frame (that is, the number of allocated tokens) increases. Therefore, when sending a large amount of data from one station, the transmission time becomes long.

On the other hand, as another token system, the allocation of tokens is completely abolished, and an arbitrary number of free tokens are acquired from any station, so that an arbitrary number of transmission areas are occupied. There is a method that allows you to send data. With this method, if the station that sends a large amount of data is a connection that can obtain the token first, the data can be sent continuously and there is no need to wait. A station with a small amount of transmission has a small number of token acquisition operations, and thus the utilization efficiency of all tokens per frame is improved. However, if a station that sends a large amount of data is logically connected downstream and another station that sends a large amount of data is connected upstream of it,
Downstream stations have less chances to obtain tokens, and large amounts of transmission data are kept waiting at the stations and overflow.

[0008]

Since the conventional multi-token system is configured as described above, in the multi-token system with fixed allocation, the data transmission time from the station transmitting a large amount of data becomes long, In addition, there is a problem that the transmission efficiency at the frame average is reduced. In addition, the token system that does not allocate token channels has a problem that although the overall transmission efficiency is improved, the upstream station is logically prioritized and the downstream station is kept waiting to perform necessary transmission. .

The present invention has been made to solve the above problems, and in the multi-token system, the number of assigned tokens in the frame of each station is variable in consideration of the total traffic volume and priority. It is an object of the present invention to obtain a token control device in which each station variably sets the number of token acquisitions according to allocation information from the master station to improve the utilization efficiency of the transmission area and at the same time shorten the transmission time of each station.

[0010]

A token control device according to the present invention comprises a control information area monitoring means for monitoring setting information from a master station and setting the number of tokens of its own station, and the above setting when transmitting data. A counter / token acquisition control means is provided for referring to the number of tokens of the own station, and controlling acquisition of the empty tokens in the same transmission frame up to the number of tokens of the own station referred to above.

[0011]

The token control device according to the present invention sets the number of tokens of its own station based on the transmitted setting information, and at the time of data transmission, it acquires and transmits the number of empty tokens up to the number of tokens of its own station.

[0012]

EXAMPLES Example 1. FIG. 1 is a transmission control block diagram of a transmitter on the station side, showing an embodiment of the present invention. In the figure, 2 is a token acquisition control unit, 4 is a data packet transmission control unit, 6 is a transmission buffer, 7 is a transmission request unit, 94 is a transmission request signal, and the value of the counter F of the counter F control unit is the initial value t. Set to. Reference numeral 95 is a token continuous acquisition request signal. Furthermore, 96 is a data amount notification line, which notifies the data amount. Reference numeral 97 is a continuous acquisition request line for notifying when a plurality of tokens are required. Reference numeral 98 is a transmission area limit line, which is a line for notifying the available transmission area limit from the number of used tokens. Reference numeral 99 denotes a token acquisition maximum number notification line, which notifies the set maximum token number. Reference numeral 100 denotes a token acquisition notification line, which informs an empty token currently reserved for information transmission and counts down the value of the counter F. Reference numeral 11 denotes a control information area monitoring unit, which detects the number of token settings assigned to the own terminal station sent from multiple stations and notifies the counter F control unit of this to determine the maximum number of tokens that can be acquired. A counter F control unit 12 counts down each time a free token is secured until the set number of tokens is reached, and controls the number of used tokens by comparing t1 and t2 described later. Reference numeral 13 is a relative number control unit, which performs control to send data in ascending order of relative numbers. A continuous acquisition determination unit 14 determines whether or not a plurality of tokens are necessary based on the amount of data to be transmitted.

FIG. 2 is a diagram showing a newly added portion of the master station. In the master station or the system-wide information amount management station, the additional portion of FIG. 2 is provided before the SEL 9 of FIG. In FIG. 1, 21 is a traffic monitoring unit, 22 is an M determination unit, 23 is an M setting / notification unit, and 20 is a selector. The system network in this embodiment is the same as that in FIG. 7 of the conventional example. FIG. 3 is a flow chart showing the operation of checking the traffic (information amount of the entire system) of the master station shown in FIG. 2 and notifying each station (terminal station) of the set token number M of that station. FIG. 4 is a configuration diagram of a transmission frame for explaining a usage example of the control information area 41 in the transmission frame for notifying the setting M from the master station to each station.

First, the traffic control method of the master station will be described. In FIG. 2, the traffic monitoring unit 21 of the master station waits for a transmission frame to arrive, as shown in the flowchart of FIG.
When the transmission frame arrives, the control information area 41 is monitored, and the currently set maximum number M of token settings and the number D of used transmission areas of each station are grasped. The traffic monitoring unit 21 notifies the M determination unit 22 of the number of used transmission areas D and the M setting / notification unit 23 of the maximum number of token settings M. The M determination unit 22 that has been notified of the number of used transmission areas D determines whether to change the number of used transmission areas D to M, and when changing, notifies the M setting / notification unit 23 of how to change.
When the number of transmission areas is equal to or larger than a certain value, M is reduced, and when the number of transmission areas is equal to or less than the certain value, M is increased. The M determination / notification unit 23 that has received the notification from the M determination unit 22 sets M, and the selector 20
Control information area 41 in the transmission frame of FIG.
The maximum number M of tokens determined in step S1 is written and notified to each slave station. When it is determined that it is not necessary to change the maximum token setting number M, the content of the control information area 41 is left as it is and the slave stations are notified. This completes the traffic monitoring and M notification operation of the master station shown in FIG.

Next, the operation of each station (terminal station) will be described. Before that, in the configuration of each slave station (terminal station), a portion different from the configuration of the conventional station will be summarized and described. The feature of the station side of this embodiment is that the control information area monitoring unit 11 that monitors the control information 41 from the master station and indicates the maximum number of tokens is provided, and that the token acquisition control unit 2 and the counter F control unit 12 are provided. This is to control the number of free tokens to be acquired in comparison with the variable setting token t. Accompanying this,
The data packet transmission control unit 4 is provided with a function of storing a plurality of relative numbers, controlling the number of transmission areas, and controlling transmission in ascending order of relative numbers. Send buffer 6
Has a function of monitoring the data amount and notifying the data amount when a large amount of data is transmitted at one time and a plurality of transmission areas need to be used. Further, the transmission requesting unit 7 is provided with a function of determining whether tokens are continuously acquired and a function of generating a request signal when continuous acquisition is required.

Each slave station notified of the maximum token setting number M sets the maximum token acquisition number t as a value relative to the maximum token setting number M in accordance with the priority. For example, it is set as M, M-1, M-2, etc. The token acquisition control unit 2 of each station
The contents (maximum number of token settings M) of the control information area 41 in the transmission frames that sequentially pass are read. The token acquisition control unit 2 sets the maximum token acquisition number t as in the above example according to the read maximum token setting number M.
However, when t <1, t = 1. When transmitting data, the token acquisition control unit 2 can acquire tokens up to the newly set maximum token acquisition number t.

The case where the station notified of the maximum token setting number M is transmitting data will be described.
The maximum number of tokens acquired before the change is t1, and the maximum number of acquired tokens after the change is t2. Token acquisition control unit 2
Compares t1 and t2, and when t1> t2, t1-t
Release the two tokens and t1 the transmission area currently in use
-T2 is abandoned, and the data packet transmission control unit 4 sets t2
Data is transmitted using the transmission areas. t1 <t2
In this case, the token acquisition control unit 2 can acquire t2-t1 tokens and can newly use t2-t1 transmission areas, and the data packet transmission control unit 4 uses t2 transmission areas. Send data.

FIG. 5 shows the slave station after the counter controller 12 has been initialized as described above.
It is a flowchart figure explaining the change operation of the counter F. The station 70, which has prepared the data packet to be transmitted, stores the data packet in the transmission buffer 6, and the transmission buffer 6 notifies the transmission request unit 7 that the data packet is ready to be transmitted. In response to this, the transmission request unit 7 sends a transmission request 94 to the token acquisition control unit 2. When the token acquisition control unit 2 receives the transmission request 94 (step 5
0), the value of the counter F is set to the initial value t (step 51). Further, the transmission requesting unit 7 looks at the amount of data in the transmission buffer 6, and if it determines that a plurality of tokens (t in this example) need to be acquired, it sends a token continuous acquisition request 95 to the token acquisition control unit 2. . In response to the transmission request 94, the token acquisition control unit 2 sequentially searches for the token 73 from the respective transmission areas 75, 76, 77 in the transmission frame 72 passing through the station 70 (step 52), and finds the first token 73. The token acquisition control unit 2 notifies the data packet transmission control unit 4 of the data packet transmission permission signal 91 and the position (relative number) 92 occupied by the transmission area including the acquired token 73 on the transmission frame 72. When the token is acquired, the value of the counter F is decremented by 1 (step 53). Then, the data packet transmission control unit 4 operates the read circuit 5 and the selector 10 at a predetermined timing to send the data packet in the transmission buffer 6 to a predetermined area (for example, the transmission area 75) in the transmission frame 72. To do.

Next, the token acquisition control unit 2 responds to the token continuous acquisition request signal 95 (step 54), and each transmission area 76, 77 in the transmission frame 72 having the same cycle as the transmission frame containing the token acquired first. Are subsequently monitored (step 55). When the token 73 is found in the transmission areas 76 and 77, the token acquisition control unit 2 acquires it and notifies the data packet transmission control unit 4 of the data packet transmission permission signal 91 and the relative number 92.
When the token is acquired, the value of the counter F is decremented by 1 (step 56). Data packet transmission controller 4
Is the notified transmission area (for example, transmission area 76)
Then, the data packet is transmitted. Each transmission area 7 in the transmission frame continues until the value of the counter F becomes 0.
The token is searched from 7 and obtained (step 57).
Then, the above operation is repeated to transmit the data packet. If only a smaller number of tokens than t tokens (for example, s (<t) tokens) can be acquired in the transmission frame having the same cycle as the transmission frame 72 including the first token (NO in step 55), Data is continuously transmitted in the next cycle using the s transmission areas.

As described above, in each station, the counter initial value of the counter F controller is set according to M designated by the master station, and thereafter, the transmission area can be occupied within the range of the set token value. Therefore, the transmission area can be assigned according to the transmission data amount and priority of each station. In addition, this can change over time of system operation. Therefore, unlike the conventional fixed allocation method, the usage efficiency of the transmission line is improved, and unlike the conventional method in which tokens are completely used freely, stations with high priority and high transmission volume are preferentially treated. The efficiency of system operation can also be improved.

Example 2. In the first embodiment, when the number of tokens that can be acquired is less than the maximum token acquisition number t (for example, s) in the transmission frame having the same cycle as the transmission frame including the first acquired token, the next cycle also has s pieces. However, in the present embodiment, when the number of tokens that can be acquired is less than the maximum number of token acquisition in the transmission frame as described above, the data is not transmitted. Unless it is completed, it will continue to search for tokens in the next cycle.

FIG. 6 is a flow chart showing the operation of the counter F which realizes the second embodiment. Station
Is the same as that of FIG. The operation of the token acquisition control unit is retained for the next cycle. Next, a transmission operation according to the second embodiment will be described with reference to FIGS. Since steps 50 to 54 operate in the same manner as the parts denoted by the same reference numerals in FIG. 2 of the first embodiment, description thereof will be omitted.

If the token acquisition control unit 2 is notified of the token continuous acquisition request 95 from the transmission request unit 7 (step 54), the data transmission is completed and the token transmission request 93 is transmitted to the data packet transmission completion control unit 3. Has not notified the token acquisition control unit 2 (step 5
If NO in step 5), the token is searched for in the transmission frame having the same cycle as the transmission frame including the token acquired first (step 56). When the token is acquired, the value of the counter F is decremented by 1 (step 57).
The token in the transmission frame is searched until the value of the counter F reaches 0 (step 58), and steps 55 to 58 are repeated. If the token acquisition maximum number t cannot be acquired in the above-mentioned transmission frame (in the case of NO in step 56), the next cycle is started (step 5).
9) Search for tokens. However, if the data transmission is completed during the token search and the data packet transmission completion control unit 3 notifies the token acquisition control unit 2 of the token transmission request 93, the token search is completed (step 55).
If YES). In addition, the data packet transmission control unit 4
Then, the data packets in the transmission buffer 6 are transferred to the respective transmission areas in the ascending order of the relative numbers 92 notified from the token acquisition control unit 2 by the selector 10 and the reading circuit 5.
And send it.

As a result of the above-described transmission operation, each station can transmit data to a plurality of transmission areas in the same transmission frame.

Example 3. In the above embodiment, the maximum number of tokens acquired is the numerical value M in the control information from the master station.
(Maximum number of settings) is specified, and each station detects this and sets it for each station. In this embodiment, the initial setting value of the counter F is not variably changed during operation, and the F value is set based on the information from the master station during a predetermined operation period, for example, every morning. Further, the F value instruction may be made by telephone or the like, in which case,
The F value may be set manually. The transmission operation in the station once the F value is set is shown in FIG. 5 described in the first and second embodiments.
The operation described in the flowchart of FIG. 6 is performed.

[0026]

As described above, according to the present invention, the control information area monitoring means for monitoring the setting information from the master station and setting the number of tokens, and the above-mentioned number of setting tokens at the time of data transmission are referred to as a free space. Since a counter / token acquisition control means for controlling acquisition of tokens up to a set number of tokens is provided, a plurality of tokens are acquired from a plurality of transmission areas of a transmission frame to increase the station data transmission amount and transmission time. There is an effect that can shorten. In addition, when the traffic volume is low, a station with a high priority can obtain a sufficient number of transmission areas to be used, which has the effect of improving the transmission area usage rate.When the traffic volume is high, a station with a high priority can be used. Since the number of transmission areas is suppressed, the number of unused transmission areas is increased, and the token waiting time of a station with low priority can be shortened.

[Brief description of drawings]

FIG. 1 is a configuration diagram of a transmission unit of a station that is an embodiment of the present invention.

FIG. 2 is a configuration diagram of a transmission addition unit of a master station according to an embodiment of the present invention.

FIG. 3 is an operation flowchart of the master station of FIG.

FIG. 4 is a configuration diagram of a transmission frame.

FIG. 5 is a flowchart showing the operation of the counter F indicating the remaining number of tokens that can be acquired according to the first embodiment of the present invention.

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

FIG. 7 is a network configuration diagram of a token ring according to a conventional multi-token system.

FIG. 8 is a transmission control block diagram of a transmitter of a conventional station.

[Explanation of symbols]

 2 token acquisition control unit 4 data packet transmission control unit 6 transmission buffer 7 transmission request unit 11 control information area monitoring unit 12 counter F control unit 13 relative number control unit 14 continuous acquisition determination unit 21 traffic monitoring unit 22 M determination unit 23 M setting Notification section 41 Control information area

Claims (1)

[Claims] 1. A control information area monitoring means for monitoring setting information from a master station and setting the number of tokens of its own station, and the same transmission by referring to the set number of tokens of its own station when transmitting data. A token control device comprising counter / token acquisition control means for acquiring and controlling empty tokens in a frame up to the number of tokens of its own station referred to above.