JPS63209347A - Buffer assignment system for data exchange network - Google Patents

Abstract

PURPOSE:To attain stable control providing an idle buffer management section managing number of idle buffers and corresponding to the boundary value of the transition to the state strengthening the restriction in each stage to a smaller idle buffer number from the boundary of the transition of restriction relax. CONSTITUTION:An idle buffer management section 11 obtains the information of return from a transmission section 8 to a high-order device and the idle buffer information of a common buffer pool 10 and the reception buffer loop 13 to apply management to an idle buffer of the buffer 10 timely in response to the buffer 13. Each stage of the restriction value of the reception buffer number is decided in response to the idle buffer number managed by the management section 11. Then the idle buffer number is decreased and the stage is transited to the strengthened restriction at the next point of time and the stage is transited to the stage of relaxed restriction with the increased idle number similarly. The condition of the transition to the strengthened restriction is not transited when the transition to the relaxed restriction reaches the idle buffer number decided smaller than the idle buffer number decided in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a buffer allocation method for a data link access protocol control device.

(Prior art) Regarding the buffer management method in packet switching, research and practical application were conducted by the Institute of Electro-Communications Engineers of Japan in the 1985 IEICE Telecommunications Division National Conference vol-178 entitled "Regional Congestion Control in Traffic Control Methods" and by Nippon Telegraph and Telephone Corporation. There are various methods described in "Traffic Control Algorithm for Packet Switched Networks" on pages 53 to 61 of Report Vol. 35 No. 5.

The former method is based on the correlation between each level value of the total busy time ratio of the incoming trunk line and each level value of the total busy time ratio of the hopper transaction memory (buffer), and the regulation is controlled and released in multiple stages. The same threshold value is used to perform congestion control.

Furthermore, the latter method performs multiple stages of congestion control on packet calls based on the correlation between the processor usage rate and the buffer usage rate.

(Problems to be Solved by the Invention) However, in the former method described above, since it is necessary to monitor the correspondence between each level value of both the incoming trunk line and the buffer, the control becomes complicated, and Since the same threshold value is used for regulation and its release, there is a risk that the control may become unstable. Also, since the buffer usage rate is not monitored, it is not suitable for controlling a storage/exchange machine.

On the other hand, in the latter method, it is necessary to monitor each correspondence between the processor usage rate and the buffer usage rate, as in the former method, so the control becomes complicated. and,
Since the control is only for packet calls, it cannot support multiple types of services.

(Means for Solving the Problems) In order to solve the above-mentioned problems, the present invention provides a data link access protocol control device that is connected to communication partner devices of a plurality of service groups, and transmits and receives information from the multiple communication partner devices. In a buffer management method that manages the number of allocated buffers for storing information, an empty buffer management unit that manages the number of empty buffers per unit time that can be used to store information for transmission and reception with a communication partner device, and a communication partner device The regulation value of the number of reception buffers used per unit time required for receiving signals from the service group is set to correspond to a predetermined number of empty buffers common to each service group, and the regulation value is set in multiple stages by corresponding to a plurality of predetermined numbers of empty buffers. A regulation setting circuit is provided for each service group, and the boundary value for transition to stricter regulation between each stage is made to correspond to a smaller number of empty buffers than the boundary value for transition to deregulation.

(Function) According to the present invention, each stage of the regulation value for the number of reception buffers is determined according to the number of empty buffers managed by the empty buffer management section. Then, as the number of empty buffers decreases, the number of empty buffers shifts to the phase of tightening regulations at that stage and the next point in time, and similarly, as the number of empty buffers increases, it shifts to the phase of relaxing regulations.However, the conditions for shifting to tightening regulations are The transition to relaxation does not occur unless the number of empty buffers becomes smaller than the specified number of empty buffers. Regulation values for each stage are set for each service group, and each service group is regulated by the regulation value.

(Embodiment) FIG. 1 shows one embodiment of the present invention, and is a system configuration diagram of a data link access protocol control device in an integrated services digital network (ISDN).

In the figure, 1 is a data link access protocol control device, 2 is a receiving unit from a lower layer, 3 is a circuit switching terminal for one service group as a communication partner device, and 4 is a packet switching terminal for another similar service group. 1 is a terminal, 5 is a processing queue, 6 is a processing device, 7 is a transmission processing queue, 8 is a transmission unit to an upper level, 9 is an upper layer device, 10 is a common buffer pool, and 11 is an empty buffer management unit.

12 is a data storage unit, 13 is a receiving buffer pool,
The data storage unit 12 stores the transmission/reception information received from the circuit switching terminal 3 or the packet switching terminal 4 in each buffer 14 provided from the reception buffer pool 13.
The data is sent to the processing device 6. Reference numeral 15 denotes a reception regulation control circuit, which regulates the storage and transmission by the data storage unit 12 based on regulation value settings, which will be described later, of the processing device 6. 16 is a lead for notification of the regulation value.

The processing device 6 complies with the data transfer function specification (SDL: 5 specific) regarding the data in the queue 5.
onand Description Language
The data is analyzed based on e), and the information content is converted to a higher level, and then sent to the transmission processing waiting queue 7. The upper transmitter 8 transmits the data in the buffer 17 of the queue 7 to the upper layer device 9, and returns used buffers to the common buffer pool 10. The empty buffer management unit 11 receives the return information from the upper-level transmission unit 8, the common buffer pool 10, and the receiving buffer pool 1.
3 empty buffer information and common buffer Boolean 1o
It manages the supply of empty buffers to the reception buffer 13 in a timely manner, and notifies the processing device 6 of the number B of empty buffers per unit time in the reception buffer pool 10 via the empty buffer notification lead 18. Reference numeral 19 is a transmitting unit to the other party's terminal.

The processing device 6 also includes a regulation setting circuit 6A, and the regulation setting circuit 6A sets regulation state variables (regulation flags) at each stage to regulate the number of reception buffers used by each terminal 3, 4.
The normal state (non-restricted state) is set to r-0, the first restricted state is set to r-1°, and the second restricted state is set to r-2. And each state r-0, r=1. Transfer between r=2 is managed by the number of buffers B notified from the empty buffer management unit 11.

FIG. 2 is a receiving buffer regulation condition diagram showing the regulation management conditions including the above-mentioned transition, and FIG. 3 is a condition diagram of transition between each regulation state.

In each figure, w, x, y, z are the number of free buffers B
Each threshold value indicates a predetermined number of buffers for checking with each other, and there is a relationship of z>y>x>W, and the threshold value W is
When the relationship with the number of empty buffers B is Bow, it forms the boundary value that sets the transition of enforcement of regulation from the first regulation state r-1 to the second regulation state r=2. And the threshold value X is Bo
When x, the second regulation state r=2 to the first regulation state r-1
This constitutes a threshold that sets the transition to deregulation. and,
The threshold value y is set from the normal state r−〇 to the first
This is the boundary value that sets the transition to stricter regulation to the regulation state r=1. When B>z, the threshold value 2 is a boundary value that sets the transition of deregulation from the first regulation state r=1 to the normal state r=o.

The regulation setting circuit 6A of the processing device 6 also sets each state r=o,
As a regulation value for rwl and r-2, the number of receiving buffers mci used per unit time required for receiving signals from each of the line switching terminal 3 and the packet switching terminal 4 is
and mpl (where i corresponds to the value of r, i-0,1
, 2), and each state r=Q, r-1, and r-
2, each regulation value mco, mpO, and mci, m
pl and mc2. mp2 to the reception restriction control circuit 15.

Furthermore, the regulation setting circuit 6A provides a transmitter to each terminal 3.4 to the other terminal when transitioning from the normal state r-0 to the first regulation state r=1 or the second regulation state r-2. Sends a notification RNR that reception is not possible (reception restriction) via 19, and when transitioning to normal state r = 0, reception is possible in the same way (restriction is lifted)
Send notification RR. Then, for the upper layer device 9, the normal state r-0 or the first restricted state r-1 to the second restricted state
When transitioning to restriction state r-2, a busy (transmission restriction) notification BUSY is sent via the transmitter 8 to the upper layer, and the state returns to normal state 1.
== Can be used in the same way when moving to Q (release of restrictions) Send gqB U S Y release.

Next, a description will be given of the operation of regulating the number of reception buffers mainly using the processing device 6 in the circuit shown in FIG.

FIG. 4 is a flowchart of the operation for regulating the number of reception buffers.

In FIG. 4, each step SL, S2. The route of END1 is a state in which the normal state r-0 in which the number of reception buffers used by the terminals 3 and 4 is not restricted is continued. That is, if the relationship between the number of empty buffers B determined by the empty buffer management unit 11 and the predetermined threshold value 2 is B>z (step S1
), when the restriction flag is r-0 (S2), the normal state continues, and each restriction value mco, mpo (non-restricted) is sent to the reception restriction control circuit 15.

The route from steps S1 to S5 and END2 is from the first regulation state r-1 or the second regulation state r-2 to the normal state r=
This shows the state of transition to o. The number of empty buffers B is at the level of stricter regulation to the normal state r-0 (SL)
, since the flag r is 1 or 2 (S2), the respective regulation values mco and mpo are set, and the normal state r=o
(S3). Then, a restriction release notification BUSY release is sent to the upper layer 9 (S4), and a restriction release notification RR is sent to each terminal 3, 4 (S5).

The routes of steps SL, SO, S7, and END3 are as follows:
Normal state r similar to the route leading to step ENDI
-0 continues.

The route from steps Sl, 86 to Sll, END4 shows a transition state from the normal state r-0 to the second restricted state r-2. That is, the regulation flag r is 0 (SB),
If the number of empty buffers B is B<w (SB), each regulation value mc7! , mp2 are set, and the second regulation state r-
It becomes 2 (SO). Then, it sends a transmission restriction notification BUSY to the upper layer 9 (510), and sends a reception restriction notification RNR to each terminal 3, 4 (S11).

Steps Sl, S6-S8, S12. Sll, E
The route of ND4 is from the normal state r-0 to the first regulation state r
-1, each regulation value met.

mpl is set (S12). Then, a reception restriction notification RNR is sent to each terminal 3.4 (S11).

Steps SL, SO, S13. S14. END5 is
The first regulation state r-1 is continuing, and each regulation value mci
, mpl is being sent.

Steps Sl, SO, S17-S19. END[
i indicates a transition state from the second restriction state r=2 to the first restriction state r-1. That is, the number of empty buffers B is B>x
(S13), and the regulation flag r is 2 (S1
4), each regulation value mal, mpl is set (S
15).

Steps SL, SB, 813. SlB, END7 indicates that the first regulation state r=1 or the second regulation state r=2 is continuing and each regulation value m c 1. .

m p 1 or mc2, mp2 is being sent.

Steps Sl, SB, S13. SIB
, S17. At END8, the second regulation state r=2 is continuing, and the regulation values mc2 and mp2 are being sent.

Steps SL, SB, 813. S1B
, S17 to S19° END9 is the first regulation state r=1
This shows a state in which the state shifts from the state to the second regulation state r=2.

Each regulation value mc2. mp2 is set, the restriction flag r becomes 2 (S18), and a transmission restriction notification BUSY is sent to the upper layer 9.

(Effects of the Invention) As explained above, according to the present invention, the number of empty buffers common to each service group is monitored, and each regulation is Since the service groups are positioned in stages and regulation values are determined for each service group, control is simplified and control can be performed with priority given to each service group. Since the boundary value for transition to stricter regulation at each stage is made to correspond to a smaller number of empty buffers than the boundary value for transition to relaxed regulation, stable control can be obtained. Furthermore, since the number of empty buffers per unit time is monitored, it is possible to obtain responsive control corresponding to minute time periods.

[Brief explanation of the drawing]

Fig. 1 is a system configuration diagram of a control device showing an embodiment of the present invention, Fig. 2 is a reception buffer regulation condition diagram, Fig. 3 is a condition diagram of transition between each regulation state, and Fig. 4 is a diagram of the first 3 is a flowchart of an operation for regulating the number of reception buffers of the circuit shown in the figure. 6A... Regulation setting circuit 11... Empty buffer management section

Claims (1)

[Claims] In a buffer management method in which communication partner devices of a plurality of service groups are connected to a data link access protocol control device and the number of allocated buffers for storing transmission/reception information from each of the communication partner devices is managed. , an empty buffer management unit that manages the number of empty buffers per unit time that can be used to accumulate information for transmission and reception with the communication partner device, and a reception buffer that is used per unit time necessary for receiving signals from the communication partner device. a regulation setting circuit in which a regulation value of the number is set for each service group in a plurality of stages in correspondence with a plurality of predetermined numbers of empty buffers in correspondence with a predetermined number of empty buffers common to each service group; A buffer allocation method for a data exchange network, characterized in that a boundary value for transition to stricter regulations at each stage is made to correspond to a smaller number of empty buffers than a boundary value for transition to relaxed regulations.