JPH0662040A - Virtual path branch-connection device - Google Patents

Abstract

PURPOSE:To branch-connect virtual paths and to distribute and collect identical information between plural stations by providing a cell duplicating means and a cell merging means inside a branch-connection device. CONSTITUTION:The device 3 is connected to the input part 12 and the output part 11 of the switch part of a communication node. When the cell of the virtual path 14 arrives at the switch part 1, branch-connection processing is performed. A recognition part 17 in the cell duplicating means 31 reads the header area of the input cell, discriminates whether it is the cell for duplicating processing or not based on an information part 18 and sends the cell to a multiplex part 19 or a duplicating part 20. Also, the recognition part 21 in the cell merging means 32 discriminates whether the input cell is a merging processing object cell or not corresponding to the information part 22, a change part 23 changes the virtual path identification number of the cell corresponding to the information part 22 or the cell is sent to the switch input part 12 without the change.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a virtual path branching / connecting device, and more particularly, in an asynchronous transfer mode (ATM) transmission network, by duplicating and merging information at a communication node, information can be economically transmitted to a plurality of stations. The present invention relates to a virtual path branching / connecting device that enables distribution or aggregation of information from a plurality of stations.

[0002]

2. Description of the Related Art In the synchronous transfer mode (STM),
A branch connection method is proposed in Japanese Patent Application No. 58-179223. This branch connection method is a data signal to be transmitted / received between a time-division highway and a station using a time-division highway between the main station and the substation when the line is branched and connected between the main station and the substation in the digital communication network. The intra-station line terminating unit accommodating is determined whether the accommodated data signal is significant. If the result of determination is that the signal is significant, data of any speed is combined with any number of lines to form a branch line.

Further, the pulse signal is terminated only when the data signal at the intra-station line terminating portion is terminated or the line setting information indicating whether the data signal is the master station or the slave station is stored and the status signal issued by the line terminating portion is significant. Perform control to emit a channel, combine data of any speed with any number of lines,
Configure unidirectional and bidirectional branch circuits for main and slave stations.

[0004]

However, since the conventional branch connection method is only for the synchronized signal in the synchronous transfer mode, the signal (cell) in the asynchronous transfer mode cannot be processed.

The present invention has been made in view of the above points, and an object of the present invention is to provide a virtual path branching / connecting device for branching and connecting virtual paths by processing cells in an asynchronous mode.

[0006]

FIG. 1 shows a first principle configuration of the present invention. In the asynchronous transfer mode, the present invention is a communication node that relays a signal (cell) transmitted from a master station when there are a master station and a plurality of slave stations, and transmits the same information to each slave station to transmit a plurality of slave stations. In the virtual path branching / connecting device 3 provided in the communication node in order to realize the branching connection of the virtual path for merging the signal sent from the communication node at the communication node and transmitting it to the main station, the input cell specifies duplication. In the case of a duplicated cell, one or more cells having the same user information part of the cell are duplicated, a predetermined number is added to the virtual path identification number in the header of each duplicated cell, and the cell is input. Output the cell and the duplicated cell, while
When the duplication of the input cell is a cell that is not designated, the cell duplication unit 31 that outputs only the input cell
When the input cell is a cell for which merging is designated, the cell merging means 32 for changing the virtual path identification number in the header of the cell to a predetermined number and transmitting the cell is provided.

FIG. 2 shows a second principle configuration of the present invention. The present invention comprises a policing means 33 for monitoring whether the flow rate of the cells merged at the communication node is less than or equal to a predetermined capacity with respect to the virtual path defined in the cell in the link to be transmitted.

FIG. 3 shows a third principle configuration of the present invention. The present invention, in the asynchronous transfer mode, has a plurality of master stations and slave stations, duplicates a signal (cell) transmitted from the master station by a communication node, and transmits the same information to each slave station. In the device, when a cell is entered,
When the cell is a cell designated for duplication, one or more cells having the same user information part of the cell are duplicated,
Assign the specified number to the virtual path identification number in the header of each duplicated cell, output the input cell and the duplicated cell, and output the entered cell only if duplication is not specified The cell duplication means 31 is provided.

[0009]

FIG. 4 is a diagram for explaining the first operation of the present invention. In the figure, the virtual path branch connection device is provided in the communication nodes a and b, thereby realizing the virtual path branch connection in which the master station (A) and the slave station (B) exist. Black circles shown in the communication nodes a and b shown in the figure indicate branching of cells, and cross circles indicate joining.

When the cell transmitted from the master station A as the cell of the virtual path VP1 arrives at the communication node a, the device of the present invention in the communication node a transfers the cell to the virtual branching / connecting device 3 in the switch unit 1 by using the routing table 2 To route. When the cell arriving at the communication node a is input to the cell duplicating means 31, the cell header area is read to recognize the cell as the duplication target cell, the cell is duplicated, and the virtual cell designated as the duplicated cell is designated. Describe the path identification number. After that, the cell duplication means 31
Sends the cell and the duplicated cell to the cell merging means 32.

The cell merging means 32 to which both cells are input is
The virtual path identification number is changed only when necessary, and then both cells are switched to the switch unit 1 of the communication node.
Output to the input side of.

Both cells input to the switch unit 1 are sent to the link to the station B and the other to the link to the communication node b according to the information in the predetermined routing table 2. Conversely, when cells of the virtual paths VP2 and VP3 are input to the communication node a, the switch unit 1 routes the cells to the virtual path branching / connecting device 3 based on the information in the routing table 2.

The cell is input to the cell duplication means 31,
If the cell has not been designated for duplication, it is directly input to the cell merging means 32.

The cell input unit of the virtual path branching / connecting device 3 reads the header area of the cell and changes the virtual path identification number so that the cell becomes a cell of the virtual path. After that, the cell is output to the input side of the switch unit 1 of the communication node a, and the cell is transmitted to the link to the main station A.

The communication node b performs the same processing as the communication node a.

As described above, the virtual path branch connection apparatus of the present invention enables virtual path branch connection in which the master station and the plurality of slave stations exist even in the asynchronous transfer mode.

FIG. 5 is a diagram for explaining the second operation of the present invention.

The figure shows a case where a private path branch connection is performed without limiting the main station. Similar to FIG. 4, the black circles shown in the communication nodes a and b shown in FIG. 5 indicate cell branches, and the cross circles indicate merging. This figure shows a station (1
Station) indicates a virtual path branch connection state in which a signal transmitted by a station is distributed to all other stations.

When the cell transmitted as the cell of the virtual path VP4 from the station A is input to the switch unit 1 of the communication node a, the switch unit 1 routes the cell to the virtual path branching / connecting device 3. Cell is cell duplication means 3
When input to 1, the cell duplication unit 31 recognizes that the cell is a duplication target cell by reading the header area of the cell, duplicates the cell, and describes the virtual path identification number designated in the duplicated cell. . After that, the cell duplication means 3
1 sends both cells to the cell synthesizing means 32.

The cell merging means 32 changes the virtual path identification number so that one cell is the cell of the virtual path VP5 to the communication node b, and similarly, the other cell s5 is set to the virtual path to the B station. The virtual path identification number is changed to make the cell of the path VP6. After that, both cells are sent to the input unit of the switch unit 1.

Virtual path branch connection is realized by applying the same processing to all the input cells shown in FIG.

The policing means 33 shown in FIG. 2 inputs the output cells of the cell merging means 32, and with respect to the virtual path in which merging is performed in the communication node, the cell flow rate after merging is changed to the virtual path in the link to which the cells are transmitted. It is possible to monitor whether the defined capacity is exceeded.

FIG. 6 is a diagram for explaining the third operation of the present invention. By configuring the virtual path branching / connecting device 3 only with the cell duplicating means 31, the communication node a distributes information in one direction from the master station A to the slave station B. The same applies to the communication node b.

[0024]

FIG. 7 is a block diagram showing the detailed construction of the first embodiment of the present invention. In the figure, a virtual path branching / connecting device 3 is provided in a communication node and connected to an output unit 11 and an input unit 12 of a switch unit 1 of the communication node.

The virtual path 14 is accommodated in the links 13 _{1 to} 13 _i connecting to the communication nodes. When the cell of the virtual path 14 reaches the switch unit 1, branch connection processing is performed. The routing table 2 is preset so that the cells reaching the switch unit 1 are sent to the output unit 11 to which the virtual path branching / connecting device 3 is connected.

The cell duplication means 31 is a duplication cell recognition unit 1
7, a duplicate cell information unit 18, a duplicate cell multiplexing unit 19, and a cell duplicating unit 20.

The duplicate cell recognizing unit 17 reads the header area of the input cell and determines whether or not the cell is a cell to be duplicated, based on the information of the duplicate cell information unit 18. When it is determined that the cell is a cell that does not undergo the duplication process, the cell is sent to the duplicate cell multiplexing unit 19. On the other hand, when it is determined that the cell is a cell to be duplicated, the cell is sent to the cell duplication unit 20.

When a cell to be duplicated is input, the cell duplicator 20 designates a duplicate cell having the same cell and user information section (payload) as the information of the information section 18 based on the information of the information section 18. The number of created virtual paths is created, and the virtual path identification number designated by the information of the information section 18 is further added to the duplicate cells. After that, the duplicate cell is sent to the duplicate cell multiplexer 19.

The multiple cell multiplexing unit 19 includes a duplicate cell recognition unit 1
The signal of the duplicate cell input from the cell duplication unit 20 is multiplexed with the signal input from the cell duplication unit 7.

The multi-cell information section 18 holds information necessary for cell duplication processing, such as an identification number of a cell to be duplicated, the number of cells to be duplicated, and a virtual path identification number given to the duplicated cell.

The cell merging means 32 is a merging cell recognition unit 2
1, a merged cell information unit 22, and a header changing unit 23.

The merging cell recognizing section 21 is a cell duplicating means 31.
Cell is input, and it is determined based on the information of the merged cell information unit 22 whether the input cell is a merge processing target cell. After that, the cell is sent to the header changing unit 23.

The header changing section 23 is a merge cell recognizing section 21.
In the cell that is determined to be a cell to be merged in, the virtual path identification number of the cell is changed based on the information in the merged cell information section 22, and the switch input section 12 to which the virtual path branching / connecting device 3 connects. Output to.

On the other hand, with respect to cells for which merge processing is not performed, the virtual path branching / connecting device 3 is used without changing the header.
Output to the switch input unit 12 connected to. The merged cell information unit 22 holds information necessary for cell duplication processing, such as the cell identification number for performing the merge processing and the virtual path identification number to be changed.

FIG. 8 is a block diagram showing the detailed structure of the second embodiment of the present invention. In the second embodiment shown in the figure, instead of the cell merging process shown in the first embodiment,
This is realized by the switch unit 1 provided in the communication node. Regarding the function of the cell duplication means 31,
It is similar to the embodiment of.

The present embodiment is a method for realizing the function of the cell merging means 32 used in the first embodiment by using the switch section 1 and the routing table 2 provided in the communication node.

The switch unit 1 provided in the ATM communication node (cross-connect node) reads the virtual path identification number from the header area of the input cell and sends the cell to the output link described in the routing table 2 as a virtual path. It has a function of changing the identification number and transmitting it. Therefore, since the switch unit 1 has the same function as the cell merging means 32 of the first embodiment, it is possible to realize the virtual path branching / connecting device 3 also in this embodiment.

When the rewriting information of the virtual number of the cell to be merged is set in advance in the routing table 2 and the cell is inserted from the cell duplication means 31 into the switch input section 12 to which the virtual path branching / connecting device 3 is connected, the cell is inserted. , The cells are routed by the switch unit 1, but at the same time, the virtual path identification number is changed to the number set in the routing table 2, and the merging process can be realized.

FIG. 9 is a block diagram showing the detailed structure of the third embodiment of the present invention. Cell duplication means 3 of this embodiment
The configurations and functions of 1 and the cell merging means 32 are the same as those of the first embodiment. The policing unit 33 includes a cell monitoring unit 24 and a policing information unit 25. The cell monitoring unit 24 monitors the flow rate of the cell input from the cell merging means 32 in the policing information unit 25 with respect to the cell having the specified virtual path identification number, and the flow rate of the cell in the link for transmitting the cell is the cell flow rate. Monitors whether or not the capacity allocated to the virtual path defined in is exceeded.

After the input cells are counted, the switch input unit 12 to which the virtual path branch / connector 3 is connected.
Sent to.

The policing information section 25 holds the virtual path identification number of the cell for monitoring the cell flow rate and the capacity value of the virtual path defined in the cell in the link to be transmitted, which is the upper limit value of the flow rate.

As described above, according to the present embodiment, the cell flow rate can be monitored when the cell flow rate after the branch connection processing is transmitted and there is a possibility that the secured capacity will be exceeded.

FIG. 10 shows the detailed construction of the fourth embodiment of the present invention. In this embodiment, the cell merging means 32 is realized by the switch unit 1 and the routing table 16 as in the first to third embodiments shown in FIG. Therefore, by using the switch unit 1 of the communication node and the routing table 2 as the cell configuration unit 5, the configurations and functions of the cell duplication unit 31 and the policing unit 33 are similar to those of the third embodiment.

FIG. 11 shows the detailed construction of the fifth embodiment of the present invention. The cell duplication unit 31 includes a duplicate cell recognition unit 17,
The multi-cell information unit 18, the multi-cell multiplexing unit 19, and the cell duplication unit 20 are included. The function thereof is the same as that of the same portion in the first to fourth embodiments. Therefore, in this embodiment, the input cell is duplicated, and only the input cell or both of the duplicated cells are sent to the input side of the switch unit 1 of the communication node.

As described above, as the virtual path branching / connecting device 3, even if only the cell duplicating means 31 is used, it is possible to send a cell from the master station to the slave station.

[0046]

As described above, according to the present invention, in the asynchronous transfer mode network, the virtual path branch connection device is connected to the switch section in the communication node, and only the virtual path cells for branch connection are input. By inputting the processed cell into the switch section again, the branch connection of the virtual path can be realized. This makes it possible to economically distribute the same information and collect the information among a plurality of stations.

[Brief description of drawings]

FIG. 1 is a first principle configuration diagram of the present invention.

FIG. 2 is a second principle configuration diagram of the present invention.

FIG. 3 is a third principle configuration diagram of the present invention.

FIG. 4 is a diagram for explaining the first operation of the present invention.

FIG. 5 is a diagram for explaining the second operation of the present invention.

FIG. 6 is a diagram for explaining the third action of the present invention.

FIG. 7 is a block diagram showing a detailed configuration of a first exemplary embodiment of the present invention.

FIG. 8 is a block diagram showing a detailed configuration of a second exemplary embodiment of the present invention.

FIG. 9 is a block diagram showing a detailed configuration of a third exemplary embodiment of the present invention.

FIG. 10 is a block diagram showing a detailed configuration of a fourth exemplary embodiment of the present invention.

FIG. 11 is a block diagram showing a detailed configuration of a fifth exemplary embodiment of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 switch part 2 routing table 3 virtual path branching / connecting device 12 switch input part 13 link 14 virtual path 17 duplicated cell recognition part 18 duplicated cell information part 19 duplicated cell multiplexing part 20 cell duplication part 21 merged cell recognition part 22 merged cell information part 23 header changing unit 24 cell monitoring unit 25 policing information unit 31 cell duplication unit 32 cell merging unit 33 policing unit a communication node b communication node A, B, C, D customer device VP1, VP2, VP3, VP4, VP5, VP6 virtual path

Claims (3)

[Claims] 1. In an asynchronous transfer mode, when a master station and a plurality of slave stations exist, a communication node that relays a signal (cell) sent from the master station transmits the same information to each slave station, A signal transmitted from a slave station is merged at the communication node,
In the virtual path branching / connecting device provided in the communication node for realizing the branching connection of the virtual path to be transmitted to the main station, if the input cell is a cell for which duplication is specified,
One or more cells having the same user information part of the cell are duplicated, a predetermined number is added to the virtual path identification number of the header of each duplicated cell, and the input cell and the duplicated cell are output. On the other hand, if the input cell is a cell that is not specified as a duplicate, the cell duplication means that outputs only the input cell and if the input cell is a cell that is designated as a merge,
A virtual path branching / connecting device comprising a cell merging means for changing a virtual path identification number of a header of the cell to a predetermined number and transmitting the cell. 2. A policing means for monitoring whether or not the flow rate of the cells merged at the communication node is less than or equal to a predetermined capacity with respect to the virtual path defined in the cell in the link to be transmitted. The virtual path branching / connecting device according to claim 1. 3. A virtual path branch in which, in the asynchronous transfer mode, a plurality of master stations and slave stations exist and a signal (cell) sent from the master station is duplicated by a communication node and the same information is transmitted to each slave station. In the connection device, when the cell is input, if the cell is a cell designated for duplication, one or more cells having the same user information part of the cell are duplicated, and each duplicated cell is duplicated. Assign the specified number to the virtual path identification number of the cell header,
A virtual path branching / connecting device, comprising: a cell duplication unit that outputs an input cell and a duplicated cell, and outputs only the inputted cell when duplication is not designated.