JPH07283818A - Cell data exchange method and exchange device - Google Patents

Abstract

(57) [Abstract] [Purpose] Even if the device uses the ATM switch unit 4, the broadcast cell data 3 used in scan transmission is used.
Can be efficiently transferred. [Structure] The cell type including the cell destination of the input cell data 3 is discriminated, and when the discriminated cell destination is addressed to a proper node, this cell data is output to the corresponding destination by the ATM switch unit 4, and the discriminated cell When the destination is at least the broadcast, the cell data is duplicately output by the broadcast data copy unit 5 to each destination indicated by the broadcast. When the cell data output from the ATM switch unit 4 and the cell data output from the broadcast data copying unit 5 compete with each other, the cell data output from the broadcast data copying unit 5 is preferentially output.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is an AT for exchanging data information between a computer, a control unit and a monitoring unit without interruption.
The present invention relates to a cell data exchange method and a cell data exchange apparatus for exchanging cell data in M (asynchronous transfer mode) cell format.

[0002]

2. Description of the Related Art Recently, in a process control system, in order to enhance control and improve a human interface of monitoring information between stations, in addition to normal physical control information, a multi-channel including voice and moving images is provided. There is a request for transmission of media data.

Generally, in a process control transmission system, devices connected to a transmission line require highly responsive data exchange with each other. Therefore, an information exchange method using a shared memory (virtual shared memory) that can be accessed at high speed without being aware of the transmission device is adopted. For example, Japanese Patent Application Laid-Open No. 64-8501 discloses the basic principle of this information exchange system.

FIG. 9 is a schematic diagram showing a LAN system applied to a process control system using this basic principle. In FIG. 9, a plurality of nodes S composed of control devices
The TN # 1 to STN # N are connected to each other by a common transmission line L. Note that, although the loop type network configuration is shown in FIG. 9, the form of the network is not particularly limited, such as a bus type network connecting the nodes in a bus shape, a star type network connecting the nodes in a star shape, or the like.

A shared memory CM is provided in each of the nodes STN # 1 to STN # N. And the node STN #
Information is exchanged between 1 to STN # N by scan transmission and message transmission.

In the scan transmission, the data transmitted between the nodes is assigned a unique memory address which is common to all the nodes incorporated in the LAN system on the shared memory CM. Each node STN # 1 to ST
In N # N, the output data DT of its own node is sequentially and cyclically
Broadcast i to other nodes or group broadcast.

When a node acquires a transmission right (right to use the common transmission line L), the node embeds output data in a predetermined transmission frame and starts transmission via the common transmission line L. Upon receiving this transmission frame, all the other nodes store it in the corresponding memory address in their shared memory CM.

In message transmission, the node that has acquired the transmission right transmits data to another node indicated by the destination address field. Only nodes whose destination address matches the address of their own node will receive this data.

Generally, data to be shared between control devices in a process control system is transmitted by scan transmission. Then, the content of the shared memory CM is updated at regular intervals. Various physical information such as control data is transmitted to each device by scan transmission. On the other hand, MAP (Ma
nufacturing Automation Protocol) MM
Information that is required for S (Manufacturing Message Specification) message exchange and is sent non-steadily between individual devices is sent by message transmission.

The ATM system is becoming the mainstream in the broadband information communication network system. In the ATM system, all packets, regardless of connection type or connectionless type, are decomposed into 53-byte fixed length cell data and transmitted. In an ATM switch based on an ATM switch, data is exchanged between a plurality of input / output ports.

In the information communication network system adopting the ATM system shown in FIG. 10, three ATM exchanges SS are mutually connected, and each ATM exchange is connected with a plurality of ATM terminals T. In the figure,
The two ATM terminals T can establish a communication path by establishing a virtual channel with each other through the ATM switch SS. In the process control transmission system, the scan transmission is executed. Efficient communication is a prerequisite. Therefore, when the above-mentioned ATM system is adopted for the process control transmission system, it is necessary that each node having the switching function can efficiently perform the broadcast communication.

Therefore, a case of performing broadcast communication by a general ATM exchange will be described. Figure 11 shows Turn
FIG. 3 is a schematic diagram showing a self-routing type ATM switch with a copy function proposed by Mr. er). (Reference; J.
S.Turner.Design of a Broadcast Packet Switching Ne
twork.IEEE Trans. Commun., 36 (6): pp. 734-743, Ju
ne 1988.) In the figure, CN, DN, and RN are a copy network, a distribution network, and a routing network, respectively. SN, R
Non-blocking self-routing SW, well known as N,
Form a Batcher-Banyan network.

As shown in FIG. 12, the CN superimposes copies a required number of times according to an identifier given to cell data or a packet when passing through each stage of the multi-stage switch to perform multicast.

FIG. 13 shows a multicast switch using a time division bus 1a known as an Olivetti switch. In this Olivetti switch, the cell data in each input queue 1b are alternately written in the output buffer 1c by the round robin method.

[0015]

However, as shown in FIG.
-Each ATM switch shown in FIG. 13 still has the following problems to be solved. That is, FIG.
1, in the turner switch shown in FIG. 12, when half of the input ports request broadcast communication (broadcast) at the same time, it is in a blocked state, and the broadcast communication does not necessarily have a one-to-one communication data designating a destination. It does not take precedence over (unicast data).

In the transmission system for process control, it is necessary that the same data is always stored in each shared memory CM of each device, and the update timing of data in the shared memory CM of a certain device is different. Delaying with respect to the shared memory CM causes malfunction and is not allowed. Therefore, the broadcast communication needs to be executed prior to the other one-to-one normal communication.

Therefore, the turner switch cannot be used in a process control transmission system. On the other hand, FIG.
In the Olivetti switch shown in FIG. 3, there is a problem that communication data is written to the unnecessary output port 3.

Although two typical types of ATM switches have been described above, the LA of the process control system is currently included in other types of ATM switches.
There was no ATM switch suitable for N scan transmission.

The present invention has been made in view of such circumstances, and even if an ATM switch is adopted by providing a broadcast data copy unit for copying broadcast data in addition to the ATM switch unit, An object of the present invention is to provide a cell data exchanging method and a cell data exchanging device capable of efficiently transmitting broadcast cell data used in scan transmission in a required direction.

[0020]

In the method for exchanging cell data according to claim 1 of the present invention, the cell type including the cell destination of the input cell data is discriminated and the discriminated cell destination is addressed to the specific node. , This cell data is output to the corresponding destination by the ATM switch unit, and if the cell destination is determined to be at least the broadcast, this cell data is output to the destinations indicated by the broadcast by the broadcast data copy unit. I am trying to do it.

In the cell data exchange method according to claim 2, in the above-mentioned exchange method, when the cell data output from the ATM switch section and the cell data output from the broadcast data copy section compete with each other, the broadcast data is transmitted. The cell data output from the copy unit is preferentially output.

Further, in the cell data exchange device according to the third aspect of the present invention, a plurality of input units to which the cell data are respectively input, a plurality of output units to which the cell data are respectively output, and an input through each input unit. A plurality of input cell discriminating units for discriminating the cell type including the destination of each of the cell data, and outputting each cell data whose cell destination is discriminated to be a unique node by each of the input cell discriminating units, corresponding to the corresponding destination. ATM switch unit for outputting to each unit, and broadcast data for overlappingly outputting each cell data whose cell destination is determined to be at least broadcast by the input cell determination unit to each output unit corresponding to each destination indicated by the broadcast When the cell data output from the ATM switch section and the cell data output from the broadcast data copy section conflict with each other, the cell data output from the broadcast data copy section is given priority. And an output cell combining unit to output Te.

According to another aspect of the cell data exchange device of the present invention, the broadcast data copying section in each of the above-mentioned means is assigned in advance for each type of cell data such as broadcast cells, group broadcast cells, specific cells and the like. When cell data is simultaneously stored in a plurality of input buffers each having a priority and a plurality of priority buffers that temporarily store the input cell data of the corresponding type, and when the cell data are simultaneously stored in the plurality of input buffers, according to the priority. An arbitration unit for adjusting output between cell data is added.

Further, in the cell data exchange device according to the fifth aspect of the present invention, with respect to the above-mentioned broadcast data copy unit, each output unit is provided for each type of cell data such as a broadcast cell, a group broadcast cell and a specific cell. On the other hand, a plurality of output selection circuits for selecting whether to output the cell data of the corresponding type are added.

According to another aspect of the cell data exchange apparatus of the present invention, the broadcast data copy section further has priorities assigned in advance in accordance with the type of each cell data, and is output from the output selection circuit. It is composed of a plurality of memories for temporarily storing the output cell data of the relevant type, and is provided with a plurality of output buffers for preferentially outputting the cell data stored in the high-priority memory to the corresponding output unit.

[0026]

The most characteristic feature of the cell data exchanging method and cell data exchanging device of the present invention is that, in addition to the ATM switch section that specializes in exchanging regular one-to-one cell data whose destination is a unique node, A broadcast data copy unit that specializes in exchanging at least broadcast cell data that is not a one-to-one unique node is provided. This broadcast data copy unit duplicates the cell data of the broadcast to each output unit indicated by the broadcast.

In order to efficiently operate the ATM switch section and the broadcast data copy section, the cell type including the cell destination of each cell data input from each input section is discriminated.

In the inventions of claims 2 and 3, when the cell data output from the ATM switch section and the cell data output from the broadcast data copy section compete with each other, the broadcast data copy section outputs Since the output cell data is prioritized to be output, the cell data whose input destination is broadcast is exchanged with priority over the normal one-to-one cell data whose destination is the specific node. To be done.

In the cell data exchange device according to the fourth aspect of the present invention, each cell data input to the broadcast data copy section is allocated in advance for each type of cell data such as a broadcast cell, a group broadcast cell, and a specific cell. It is temporarily stored in each priority buffer having each priority. Then, the arbitration unit performs the output adjustment between the cell data according to the priority.

Therefore, the output process of the output unit in the broadcast data copy unit is executed in a shorter time for the cell data of higher priority type. In the cell data exchange device according to claim 5, each cell data input to the broadcast data copy unit is output by the output selection circuit for each type of cell data such as a broadcast cell, a group broadcast cell, and a specific cell. The output part to be selected is selected.

Therefore, group broadcast communication designating a plurality of destination nodes can be easily performed. In the cell data exchange device according to the sixth aspect, even when the plurality of types of cell data described above are simultaneously output to each of the output units selected by the output selection circuit, they are output according to the priority inspection.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1A is a block diagram showing a schematic configuration of a cell data exchange apparatus adopting the cell data exchange method of the embodiment.

As shown in the figure, the cell data exchange apparatus 2 of the embodiment is roughly divided into eight input lines i1 to i8 from No. 1 to No. 8 and cell data having the structure shown in FIG. 8 input units 9 to which 3 is input, and each input unit 9
Eight input cell discriminators 7, ATM switch units 4, broadcast data copy units 5, management units 6, and eight output cell synthesis units 8 for discriminating the type of cell data 3 input via , Cell data for eight output lines 1 to 8
It is composed of eight output units 10 for outputting 1 to o8.

The cell data 3 input to the cell data exchange device 2 via the input lines i1 to i8 is, as shown in FIG. 1 (b), a header of 5 bytes, a payload of 48 bytes,
SDH (Synchronous Digital Hi) with a fixed length of 53 bytes in total
(Erarchy) format ATM cell data.

FIG. 2 is a detailed block diagram showing the configuration of each input unit 9 and management unit 6. Although there are eight input lines and eight output lines, only the portion corresponding to one line is shown in the figure.

From the input line (input port) i to S of the input section 9
The data that has entered the DH / ATM processing unit 9a is decomposed into ATM cells. This cell data 3 enters the next FIFO (First In First Out Register) 9b, and then the input cell discrimination unit 7 inspects the VPI / VCI and PT (payload type) of the header.

Information for discriminating the type of the input cell data is stored in the input cell discrimination information section 11. M
When the PU (microprocessor) 12 receives the management message at the time of initial setting and during operation, it writes the discrimination information into the input cell discrimination information section 11 as necessary. MPU12
The software executed by is written in the program memory 13.

When the input cell discriminating unit 7 determines that the received cell data 3 is the management cell or the control cell, the cell data 3 is temporarily stored in the FIFO 14. FIF
The cell data stored in O14 is written in the memory 15 together with the cell data 3 input from the other input unit 9. MP
When detecting that the management cell or the control cell is written in the memory 15, the U12 reads the information of the payload of the cell data 3 and controls according to the content. Also, MP
U12 outputs a management cell from the management cell output part 15 as needed.

When the input cell discrimination unit 7 determines that the received cell data 3 is a user plane cell for one-to-one communication with only one destination, the cell data 3 is A
It is sent to the TM switch unit 4, and the output unit 10 to which the output line o is connected is determined inside the ATM switch 4.

In the input cell discriminating unit 7, the received cell data 3 is the management cell. If it is not a control cell and is not a normal user plane cell, that is, the received cell data 3
Is determined to be a broadcast user plane cell including a scan transmission cell, the cell data 3 is sent to the broadcast data cell copy unit 5. It should be noted that, in addition to the normal broadcast cell for transmitting the corresponding cell data 3 to all the nodes, a group broadcast cell for transmitting the corresponding cell data 3 to a limited plurality of nodes and a specific broadcast cell for this user plane cell Contains cells.

In the case of a normal broadcast communication cell, the cell data sent to the broadcast data cell copy unit 5 is internally output to the entire output unit 1
The cell data 3 is copied for 0, but in the case of a group broadcast cell, there is an output unit 10 that is not copied appropriately.
For example, when outputting from the input line i1 only to the output lines o1 to o3, the cell data 3 is not copied to the output lines o4 to o8.

The cell data 3 output from the ATM switch 4, the broadcast data cell copy unit 5, and the management unit 6 is temporarily stored in the output cell synthesis unit 8 for each output line. FIG. 3 is a block diagram showing a schematic configuration of one output cell synthesizing unit 8 among the eight output cell synthesizing units 8.

The normal cell data output from the ATM switch unit 4 and the management cells and control cells output from the management unit 6 are stored in the FIFO queue 17a. It is input to 17b. The heads of the FIFO queues 17a and 17b are latched by the respective latch gates 18a and 18c, and when the head data is output, the FIFO queues 17a and 17b are output.
The next cell data in the above is sent to the latch gate portions 18a and 18c. The broadcast communication cells, the group broadcast communication cells and the specific cells output from the broadcast data cell copy unit 5 are latched by the latch gate unit 18b. Each latch gate section 18
a. When cell data is latched in 18b and 18c,
Output request signal ARE to gate output control unit 19
Send Q, BREQ, CREQ.

The gate output controller 19 is composed of a plurality of logic circuits and one priority storage 21 as shown in FIG. In FIG. 4, each output request AREQ input from the latch gate 18a of the output of the ATM switch unit 4, the latch gate 18c of the output of the management unit 6, and the latch gate 18b of the output of the broadcast data cell copy unit 5,
For each of CREQ and BREQ, each latch gate 18a.
18c. 18b to gate signals AGRT,
Send CGRT and BGRT.

Further, in FIG. 4, each delay unit 20a. Two
0b. Reference numeral 20c is a delay element for enabling the gate signal for the time corresponding to one cell data. Further, the order storage unit 21 stores the order for enabling the AGRT and the CGRT alternately, and when the positive logic is set, the AGRT and the CGRT are enabled.
Allow RT to enable CGRT in negative logic.

As a result, the gate output controller 19
The output request BREQ of the broadcast data cell copy unit 5 is arbitrated by giving the highest priority to the other output requests AREQ and CREQ. In this way, the gate output control unit 19 includes the latch gate units 18a, 18b. The output request signal is received from 18c, and the latch gate unit 18b of the broadcast data cell copy unit 5 is received.
When there is an output request from cell data, the latch gate section 18b corresponding to the broadcast data cell copy section 5 outputs cell data.

When there is no output request from the broadcast data cell copy section 5, the gate output control section 19 has a latch gate section 18a corresponding to the ATM switch section 4 and a latch gate section 18c corresponding to the management section 6. To allow cell data to be output alternately in a round robin format.

That is, in FIG. 2, the output cell synthesizing unit 8 functions so that the broadcast communication cells, the group broadcast communication cells and the specific cells output from the broadcast data cell copying unit 5 are output units 10 as the highest priority cells. Is output to. The normal communication cells output from the ATM switch 4 and the management cells and control cells output from the management unit 6 are output by the output unit 10 only when the cell data 3 is not output from the broadcast data copying unit 5.
Is output to.

Further, when the cell data 3 is output from the broadcast data cell copy unit 5, the broadcast data cell copy unit 5 is busy with respect to the ATM switch unit 4 and the corresponding output unit 10 of the management unit 6. A signal is sent to stop the output from the ATM switch unit 4, the management unit 6, or the corresponding output unit 10 of both.

From the above results, when performing the scan transmission and the specific data cell transmission on the basis of the ATM cell, these cell data are exchanged by giving priority to other normal cell data for one-to-one communication. Since it can pass through the device 2, the reliability and efficiency of scan transmission can be improved.

Next, the structure and operation of the synchronous data copy section 5 will be described. FIG. 5 is a block diagram showing a schematic configuration of the synchronous data copy unit 5. As shown in the figure, the synchronous data copy unit 5 includes eight serial-parallel (S / P) conversion units 22 corresponding to eight input lines and eight input buffers 2.
3, broadcast copy bus BB, and eight output selection circuits 25
, Eight output buffers 26, eight parallel-serial (P / S) converters 27 corresponding to eight output lines, and
And two arbitration units 24.

In FIG. 5, each cell data 3 input through each input unit 9 and each input cell determination unit 17 is converted into parallel 16 bits by the serial-parallel conversion unit 22. The cell data converted into the 16-bit width is packed in the input buffer 23 in the FIFO format.

As shown in FIG. 6, each input buffer 23 is composed of a plurality of prioritized buffers 33a, 33b, 33c controlled by the arbitration unit 24. Priority levels are assigned to the priority level buffers 33a, 33b, 33c, respectively.

Generally, the input cell data contains a priority identifier. In the apparatus of the embodiment, the types of cell data 3 which are discriminated by the input cell discriminating unit 17 and input to the broadcast data self-reply unit 5 are a broadcast cell, a group broadcast cell and a specific cell. Then, these types are assigned to the respective prioritized buffers 33a, 33b, 33c.
Assigned to. Each priority is 33a, 33b, 3
The order is 3c.

Then, the respective prioritized buffers 33a, 33a
At the time when the cell data is written in 3b and 33c, the respective prioritized buffers 33a, 33b and 33c request the arbitration unit 24 to output the bus to the broadcast copy bus BB.

The arbitration unit 24 stores the priority buffers 33b of intermediate priority in the case where there is no bus output request from the priority priority buffers 33a of all the output units 10 including the other input buffers 23. The bus output request is permitted and the corresponding cell data 3 is output to the broadcast copy bus BB.

Further, the arbitration unit 24 assigns the lowest priority to each output buffer 23 when there is no bus output request from each of the highest priority buffers 33a and 33b of the intermediate priority. The bus output request of the buffer 33c is permitted and the corresponding cell data 3 is output to the broadcast copy bus BB.

As described above, each input buffer 23 and the arbitration unit 24 are prioritized in accordance with the cell type such as the broadcast communication cell, the group broadcast communication cell and the specific cell input to the broadcast data cell copy unit 5. It is sent with a degree to the broadcast copy bus BB.

Therefore, even if the cell data belong to the same broadcast classification, the broadcast cells addressed to all nodes can be passed through the broadcast data cell copy section 5 with the highest priority. .

Therefore, the scan transmission efficiency when the cell data exchange device 2 is incorporated in the process control data transmission system can be further improved. In FIG. 5, each cell data 3 output from each input buffer 23 to the broadcast copy bus BB is input to each output selection circuit 25 corresponding to each output unit 10.

As shown in FIG. 7, each output selection circuit 25 includes a FIFO key 28, a cell identification information register 29, an associative memory 30, an output controller 32. It is composed of a gate connected to the output buffer 26.

In the associative memory 30, the output selection circuit 25 is connected for each type of cell data such as a broadcast communication cell, a group broadcast communication cell, a specific cell, etc. Information on whether or not to output data is stored. This information is written in the associative memory 30 at the time of initial setting via the management bus 31 or when the management control information is received.

The cell data 3 fetched from the broadcast copy bus BB is fetched in the FIFO queue 28. The portion corresponding to the cell header portion of the cell data 3 fetched in the FIFO queue 28 and the payload portion specific data are the destination register. Cell identification information register 29 including an identifier register
Latched on.

If the cell type that matches the cell identification information of the received cell data is stored in the associative memory 30 as being incapable of output, the output control section 32 outputs the FIFO queue 28.
The cell data 3 taken in is invalidated and discarded.

In the broadcast data cell copy section 5 incorporating the output selection circuit 25 for performing such an operation, by appropriately setting the setting contents in the associative memory 30,
The cell data 3 input to the broadcast data copy unit 5 is output by the output selection circuit 25 by the output unit 10 which is to be output for each type of cell data such as broadcast communication cells, group broadcast communication cells, and specific cells. To be selected.

Therefore, not only general broadcast communication transmitted to all nodes but also group broadcast communication designating a plurality of specific nodes can be carried out at the same time. Therefore, the applicable range of the cell data exchange device 2 can be greatly expanded. as a result,
The switching device can be more suitable for scan transmission.

It should be noted that the present invention is not limited to the above embodiment, it is also possible to output cell data when there is a matching cell identifier in the associative memory 30, and group broadcast information, valid / invalid in the associative memory 30. It is also possible to form the selection circuit by including information.

In FIG. 5, the cell data 3 output from each output selection circuit 25 is input to the corresponding output buffer 26. As shown in FIG. 8, each output buffer 26 has a priority assigned in advance in accordance with the type of each cell data, and temporarily stores the cell data of the relevant type output from the output selection circuit 25. FIFO queues 34a, 34b, 34c of
Latch gates 18a and 18 for controlling the output of the cell data output from 34b and 34c to the corresponding output section 10.
b, 18c, priority distribution unit 35, and priority control unit 3
6 and 6.

Then, the cell data 3 output from the output selection circuit 25 has the priority F corresponding to its own cell type such as the above-mentioned broadcast communication cell, group broadcast communication cell and specific cell.
The IFO queues 34a, 34b, 34c are once latched. Further, in this embodiment, the ATM switch unit 4
The normal cell data output from the priority distribution unit 35
Through each of the FIFO queues 34a, 34 according to the priority
b, 34c.

Three types of FIFO queues 34a. 24b. Each cell data 3 output from 34c is controlled by the priority control unit 36 such that the high priority FIFO queue 34a is output with priority.

In the broadcast data cell copy section 5 in which the output buffer 26 having the above-mentioned structure is incorporated, even for each output section 10 selected by the output selection circuit 25, the plurality of types of cell data 3 described above are stored. Are output at the same time,
It is output according to the priority order. Therefore, more complete priority control is possible.

[0072]

As described above, in the cell data exchanging method and cell data exchanging device of the present invention, an ATM for exchanging ordinary cell data for one-to-one communication.
In addition to the switch unit, a broadcast data copy unit for copying the cell data of the broadcast cell is provided. Therefore, even if A
Even if the TM switch is adopted, the broadcast cell data used in the scan transmission can be efficiently transferred in the required direction.

When the output of the ATM switch section and the output of the broadcast data copy section compete with each other, the cell data output from the broadcast data copy section is preferentially output, which is essential for scan transmission. Broadcast communication can be executed with the highest priority, and the reliability of the entire control system incorporating this cell data exchange device can be further improved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a schematic configuration of a cell data exchange device according to an embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of a management unit in the apparatus of the embodiment.

FIG. 3 is a block diagram showing a schematic configuration of an output cell synthesizing unit in the device of the embodiment.

FIG. 4 is a logic circuit diagram showing a detailed configuration of a gate output control unit in the output cell synthesis unit.

FIG. 5 is a block diagram showing a schematic configuration of a synchronous data cell copy unit in the apparatus of the embodiment.

FIG. 6 is a block diagram showing a detailed configuration of an input buffer in the synchronous data cell copy unit.

FIG. 7 is a block diagram showing a detailed configuration of an output selection circuit in the synchronous data cell copy unit.

FIG. 8 is a block diagram showing a detailed configuration of an output buffer in the synchronous data cell copy unit.

FIG. 9 is a diagram for explaining scan transmission using a general LAN system.

FIG. 10 is a schematic diagram showing a communication network system using three ATM exchanges.

FIG. 11 is a schematic diagram showing a turner type ATM switch.

FIG. 12 is a diagram showing a copy network incorporated in the same ATM switch.

FIG. 13 is a schematic diagram showing an Olivetti-type multicast switch.

[Explanation of symbols]

1a ... Time division bus, 1b ... Input queue, 1c ... Output queue, 2 ... Cell data exchange device, 3 ... Cell data, 4 ... A
TM switch section, 5 ... Broadcast data cell copy section, 6 ... Management section, 7 ... Input cell discriminating section, 8 ... Output cell combining section, 9 ...
Input unit, 9a ... DH / ATM processing unit, 9b ... FIFO,
10 ... Output unit, 11 ... Input cell discrimination information unit, 12 ... Microprocessor (MPU), 13 ... Program memory,
14 ... FIFO, 15 ... Memory, 16 ... Management cell output section, 17a, 17b, 17c ... FIFO queue, 18
a, 18b, 18c ... Latch gate, 19 ... Gate output control section, 20a, 20b, 20c ... Delay section, 21 ... Sequence storage section, 22 ... Serial-parallel (S / P) conversion section,
23 ... Input buffer, 24 ... Arbitration unit, 25 ... Output selection circuit, 26 ... Output buffer, 27 ... Parallel-serial (P / S) conversion unit, 28 ... FIFO queue, 29 ... Cell identification information register, 30 ... Associative memory , 31 ... Management bus, 32 ... Output control unit, 33 ... Priority buffer, 34
... Output FIFO queue, 35 ... Priority distribution section, 36 ...
Priority control unit, STN # i ... Node, LAN ... Common transmission line, CM ... Comment memory, SS ... ATM switch, T ... A
TM terminal, i1 to i8, I1 to I8, i ... Input line, o1 to
o8, O1 to O8 ... Output line, G ... Gate

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location 9466-5K H04L 11/20 D

Claims (6)

[Claims] 1. A cell type including a cell destination of input cell data is discriminated, and when the discriminated cell destination is addressed to a specific node, the cell data is output to the corresponding destination by an ATM switch unit, and the discriminated cell is determined. A cell data exchange method in which, when the destination is at least a broadcast, the cell data is duplicately output to each destination indicated by the broadcast by the broadcast data copy unit. 2. When the cell data output from the ATM switch section and the cell data output from the broadcast data copy section conflict with each other, the cell data output from the broadcast data copy section is given priority. The cell data exchange method according to claim 1, wherein the cell data exchange is performed. 3. A cell type including a plurality of input sections each receiving cell data, a plurality of output sections each outputting cell data, and a destination of each cell data input via each of the input sections. A plurality of input cell discriminating units, an ATM switch unit that outputs each cell data whose cell destination is discriminated to be a unique node by each input cell discriminating unit to an output unit corresponding to the destination; From the ATM switch unit, a broadcast data copy unit that duplicately outputs each cell data whose cell destination is determined to be at least a broadcast by the cell determination unit to each output unit corresponding to each destination indicated by the broadcast. When the output cell data and the cell data output from the broadcast data copy section conflict with each other, the output cell synthesizing section that preferentially outputs the cell data output from the broadcast data copy section And a cell data exchange device having. 4. The broadcast data copy unit is a broadcast cell,
A plurality of input buffers each having a priority assigned in advance for each type of cell data such as a group broadcast cell and a specific cell, and a plurality of priority buffers for temporarily storing the input cell data of the corresponding type 4. The cell data exchange device according to claim 3, further comprising: an arbitration unit that performs output adjustment between the cell data according to the priority when the cell data are simultaneously stored in a plurality of input buffers. . 5. The broadcast data copy unit is a broadcast cell,
4. A plurality of output selection circuits for selecting whether or not to output the cell data of the corresponding type to each output unit for each type of cell data such as a group broadcast cell and a specific cell. Alternatively, the cell data exchange device according to item 4. 6. The broadcast data copy unit has a plurality of priorities assigned in advance according to the type of each cell data, and temporarily stores the cell data of the relevant type output from the output selection circuit. 6. The cell data exchange device according to claim 5, further comprising a plurality of output buffers, each of which includes the above memory, and outputs the cell data stored in the high priority memory to the corresponding output unit with priority.