KR100441879B1 - ATM switch system having partially duplicable transmission line board and method therefor - Google Patents

Abstract

The present invention relates to an Asynchronous Transfer Mode (ATM) switch system capable of variable redundancy of a transmission line board and a method for switching ATM cells. More specifically, the ATM switch system of the present invention receives an ATM cell and performs switching. Switching means; An input switch interface for receiving the ATM cell through a plurality of paths and transmitting the received ATM cell to the switching means; An output switch interface for receiving the switched ATM cells from the switching means and outputting them externally; And a first mode in which only ATM cells input through any one of the ATM cells received at the one input switch interface are transmitted to the switching means, or the ATM cells received at the one input switch interface are switched. And a switch interface controller for controlling to be transmitted in any one of the second modes transmitted through independent paths within the means.

According to the above configuration, the present invention can reduce the transmission cost of the system due to the same redundancy function of the existing switch board and the variable redundancy function of the transmission line board, and at the time of replacing the switching means. Only the module can be replaced without changing the circuit, thereby reducing the cost of expansion of the switch board.

Description

ATM switch system having partially duplicable transmission line board and method therefor}

The present invention relates to an ATM switch system in an Asynchronous Transfer Mode (ATM) access node. More particularly, the present invention relates to an ATM switch system and method capable of variably redundant transmission line boards.

The communication system must process the input data on the basis of high stability and output it to the desired position without interruption. Accordingly, various methods have been proposed to minimize the interruption of data transmission due to the system itself.

The most common fault-tolerance technique used in communication systems requiring high reliability is the redundant design of hardware. Redundancy of all the hardware in the system may be the best way, but it can be economically disadvantageous. For this reason, in the Asynchronous Transfer Mode (ATM) switch system, a spare board for the main processor board and the power supply board, which are necessary for the system, is reserved in case of a failure, but in the switch board and the transmission line board for transmitting data, only the switch board is used. Redundancy is implemented by securing extra boards, and each board does not have an extra board.

1 is a redundant control apparatus for an ATM switch according to the prior art, and shows a configuration diagram of a conventional ATM switch duplication control apparatus (Patent registration No. 237398) that performs a redundancy transfer when a failure is detected.

The redundancy control device of the ATM switch board shown in the prior art is configured to duplex each ATM switch and the input and output links of the switch in a full duplex method, and to the existing buffer control circuit so that the redundancy switching of the ATM switch is performed in the state of buffer synchronization. Circuits 105a and 105b for redundancy control were added.

The additional redundancy control circuit is composed of registers for reading and writing address buffer write pointer values from the master ATM switch board according to data information exchanged between control periods, and comparators for comparing these values with the current read pointer values. do. The two ATM switch boards configured in this way are redundant in both the link and the switch, so the minimum unit redundancy can be switched.When operating in the operating state, buffer synchronization is performed so that one of the two ATM switch boards can be operated in the down state due to a fault. It can be operated as a master ATM switch immediately after switching to the state.

However, in the above case, if a failure occurs in the transmission line board, the data transmission service provided by the board is stopped, but there is no countermeasure, and all transmission line boards are prevented in order to prevent a failure in the transmission line board. In case of redundancy, the problem of excessive economic burden arises.

The ATM switch system at the access node is oriented to whether the transmission line board should be reliable and stable, or to accommodate more users. Existing dual ATM architectures have doubled the price per transmission line board when duplexing transmission line boards, and the number of physically mountable boards can be reduced by half. Because they avoided, only ATM switch boards implemented redundancy.

An object of the present invention is to provide an ATM switch system capable of variably redundant transmission line board to solve the above problems.

In addition, an object of the present invention is to provide a method for switching ATM cells by variably redundant transmission line board to solve the above problem.

It is also an object of the present invention to provide a computer readable recording medium for realizing the above method.

1 is a block diagram of a conventional ATM switch redundancy apparatus,

2 illustrates a preferred embodiment of the ATM switch system of the present invention in which a switch board is duplexed and a transmission line board is variably duplexed.

FIG. 3 illustrates an embodiment of the present invention, which simplifies FIG. 2.

4 illustrates the structure and operation mode of a switch interface element (2 × 2 exchange switch),

5A illustrates one embodiment of the present invention operating in an independent operating mode,

5b and 5c illustrate one embodiment of the present invention operating in a redundant operation mode,

5d illustrates an embodiment of the invention in which only a portion operates in an independent operating mode,

6 is a flow chart illustrating a method of the present invention.

* Explanation of symbols for the main parts of the drawings

220a, 220b, 230a, 230b, 520a, 520b, 530a, 530b transport block

220-1a, 220-2a, ...., 220-na, 220-1b, 220-2b, ...., 220-nb, 320a, 320b, 520-1a, 520-2a, ... , 520-na, 520-1b, 520-2b, ...., 520-nb Transmission Line Board Ingress Block

230-1a, 230-2a, ...., 230-na, 230-1b, 230-2b, ...., 230-nb, 330a, 330b, 530-1a, 530-2a, ... , 530-na, 530-1b, 530-2b, ...., 530-nb transmission line board egress block

203-1a, 203-2a, ...., 203-na, 203-1b, 203-2b, ...., 203-nb, 303a, 303b, 503-1, 503-2, ... 503-n input switch interface

204-1a, 204-2a, ...., 204-na, 204-1b, 204-2b, ...., 204-nb, 304a, 304b, 504-1, 504-2, ... 504-n output switch interface

201a, 201b, 301a, 301b, 501 switching means

202a, 202b, 302a, 302b, 402, 502 switch interface controls

321a, 321b ingress interface

331a, 331b egress interface

322a, 322b Ingress ATM Cell Processor

332a, 332b Egress ATM Cell Processor

The present invention to achieve the above object is a switching means for performing switching by receiving an ATM (Asynchronous Transfer Mode) cell (cell); An input switch interface for receiving the ATM cell through a plurality of paths and transmitting the received ATM cell to the switching means; An output switch interface for receiving the switched ATM cells from the switching means and outputting them externally; And a first mode in which only ATM cells input through any one of the ATM cells received at the one input switch interface are transmitted to the switching means, or the ATM cells received at the one input switch interface are switched. It provides an ATM switch system comprising a switchboard including; switch interface control unit for controlling to be transmitted in any one of the second mode state transmitted through the independent path in the means.

The present invention also provides a method for switching ATM cells in an ATM switch system, the method comprising: (a) inputting an ATM cell to a switchboard through different paths; (b) confirming a transmission line operating mode; (c) switching only the ATM cells input through any one of the ATM cells input through the different paths when the transmission line operation mode identified in step (b) is the first mode; And (d) switching the ATM cells input through the different paths through independent paths when the transmission line operation mode identified in step (b) is the second mode. Provide a method of switching.

The present invention also provides a method of switching an ATM cell in an ATM switch system, the method comprising: (a) receiving input data through a plurality of transmission line boards; (b) converting the input data into an ATM cell; (c) copying the converted ATM cells and inputting the copied ATM cells into a plurality of different switch boards; (d) checking whether an error has occurred in an ATM cell input from a first transmission line board among ATM cells inputted from the plurality of transmission line boards to the plurality of switch boards; (e) if it is determined that no error occurs in the ATM cell checked in step (d), switching the inspected ATM cell; (f) If it is determined that an error occurs in the ATM cell checked in step (d), it is determined whether there is an error in the ATM cell inputted from the transmission line boards except the first transmission line board, and there is no error. Switching an ATM cell; (g) checking whether an error has occurred in an ATM cell switched in a first switch board among the ATM cells switched in each different switch board; (h) if it is determined that no error occurs in the ATM cell checked in step (g), outputting the checked ATM cell to the outside; And (i) if it is determined that an error has occurred in the ATM cell checked in the step (g), outputting the switched ATM cell from the switch board except the first switch board to the outside. It provides a method of switching.

The present invention also provides a computer readable recording medium having recorded thereon a program for realizing the above method.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 2 illustrates a preferred embodiment of an ATM switch system of the present invention, and is a diagram showing the overall structure of a system in which a switch board is duplexed and a transmission line board is variably duplexed.

The transmission blocks 220a, 220b, 230a, 230b of the ATM switch system of the present invention are the transmission line board ingress blocks 220-1a, 220-2a, ... 220-na, 220-1b, 220-. 2b, ..., 220-nb) and transmission line board egress blocks 230-1a, 230-2a, ..., 230-na, 230-1b, 230-2b, ..., 230 -Nb) has a slot for mounting 2N transmission line boards, and each transmission line slot is connected to both switch board A 200a and switch board B 200b for redundancy of the switch board. One transmission line board is composed of one transmission line board ingress block and one transmission line board egress block. Ingress refers to the direction from the transmission line board to the switch board 200, and egress refers to the direction from the switch board 200 to the transmission line board.

The transmission blocks 220a, 220b, 230a, 230b are 2N transmission line board ingress blocks 220-1a, 220-2a, ... 220-na, 230-1a, 230- on the a side 220a, 230a. 2A, ... 230-na) and 2N transmission line board egress blocks 220-1b, 220-2b, ... 220-nb, 230-1b, 230-2b, on the b side (220b, 230b) ... 230-nb) are connected. The a side board and the b side board can be operated independently, and when the transmission line is redundant, the a side board and the b side board are grouped one by one to operate normally and one as a spare board.

The switch board 200 receives an ATM cell from each transmission line board ingress block 220-1a, 220-2a, ... 220-na, 220-1b, 220-2b, ... 220-nb. An input switch interface 203 for transmitting to a switching means, a switching means 201 of 2N x 2N or N x N type for switching the input ATM cell, and an ATM cell switched by the switching means 201 for each transmission line Output switch interface 204 and input switch interface 203 to the board egress blocks 230-1a, 230-2a, ... 230-na, 230-1b, 230-2b, ... 230-nb ) And a switch interface control unit 202 for controlling a transmission line operation mode of the output switch interface 204. Since both switch boards 200a and 200b perform the same function, almost the same time without a change in the transmitted cell. Is output to the destination transmission line board.

One of the two switch boards 200a operates in an operation mode that preferentially switches an ATM cell, and the other 200b switches an ATM cell that is switched in the switch board 200a operating in an operation mode. When it occurs, it operates in standby mode, which waits to switch the ATM cell and output it to the outside. In this embodiment, for convenience, the switch board 200a will be described as a switch board operating in an operation mode and the switch board 200b as a switch board operating in a standby mode.

Since the operation of the switch board 200a in the operation mode and the switch board 200b in the standby mode is the same as the input switch interface and the output switch interface, only the operation mode switch board 200a will be described here.

The input switch interface 203a and the output switch interface 204a determine the transmission path of the input ATM cell under the control of the transmission line operation mode determined by the switch interface controller 202a. That is, when the transmission line operation mode is a duplex operation mode in which the transmission line is duplicated, the input switch interface 203a and the output switch interface 204a may be any of the ATM cells inputted from both transmission line board ingress blocks 220a and 220b. The path is set to switch only one ATM cell. That is, in the transmission line boards connected to one input switch interface 203 and the output switch interface 204, information related to connection establishment such as routing information and traffic control parameters for transmission is simultaneously set at the time of connection establishment, but is actually transmitted. The path for is activated on only one of the two boards.

When the transmission line operating mode is an independent operation mode in which the transmission line is not redundant, the input switch interface 203a and the output switch interface 204a are each independent of ATM cells inputted from both transmission line board ingress blocks 220a and 220b. Set the path to switch through the path. That is, when the transmission line operating mode is an independent operation mode, each transmission line board independently performs a transmission service.

2 illustrates an example of duplication of a switch board, the switch interfaces 203 and 204 connected to one transmission line board 220 and 230 should be operated in the same transmission line operation mode. For example, if the transmission line operating mode of the input switch interface 1 203-1a connected to the transmission line board ingress block 1 220-1a is an independent operation mode, the same transmission line board ingress block 1 220-1a is used. ), The transmission line operation mode of input switch interface 1 (203-1b) connected to the s) should also be an independent operation mode.

Similarly, if the transmission line operating mode of the output switch interface 1 204-1a connected to the transmission line board egress block 1 230-1a is an independent operation mode, it is connected to the same transmission line board egress block 1 230-1a. The transmission line operating mode of input switch interface 1 204-1b should also be an independent operating mode.

Whether the switch interfaces 203 and 204 operate in the independent operation mode or the redundant operation mode is controlled by the switch interface control unit 202.

FIG. 3 is a simplified diagram of FIG. 2 and illustrates a side transmission line board including an ingress block 320a of transmission line board A and an egress block 330a of transmission line board A; B-side transmission line board composed of ingress block 320b of transmission line board B and egress block 330b of transmission line board B, input switch interface 303, output switch interface 304, and switch interface controller 302. ), An ATM cell switch system composed of two switch boards 300a and 300b with a switching means 301.

The ingress block 320a of the transmission line board A includes an ingress interface 321a, an ingress ATM cell processor 322a, a terminal 0 323a, and a terminal 1 324a. The ingress block 320b of the transmission line board B also includes the same components.

The ingress ATM cell processor 322a receives externally input data and converts it to an ATM cell. The ingress interface 321a is a portion mounted for redundancy of the switch board 300 and copies the ATM cells converted by the ingress ATM cell processor 322a to the same number as the number of the switch boards 300. In FIG. 3, since there are two switch boards, they are copied to two ATM cells. The copied ATM cell is simultaneously delivered to each input switch interface 303a, 303b of both switch boards 300a, 300b via terminal 0 323a and terminal 1 324a.

The switch board 300 includes an input switch interface 303, a switching means 301, an output switch interface 304, and a switch interface controller 302, wherein both switch boards 300a and 300b have the same function. Therefore, the output is output to the destination transmission line board at about the same time without changing the transmitted cell.

As illustrated in FIG. 2, one of the two switch boards 300a operates in an operation mode, and the other 300b operates in a standby mode. In the present embodiment, for convenience, the switch board 300a will be described as a switch board operating in an operation mode and the switch board 300b as a switch board operating in a standby mode.

Since the operation of the switch board 300a in the operation mode and the switch board 300b in the standby mode are the same, only the switch board 300a in the operation mode will be described here.

The input switch interface 303a and the output switch interface 304a are elements that determine the transmission path of the input ATM cell under the control of the switch interface controller 302a, and are preferably 2x2 switch elements.

4 illustrates an example of a switch interface 403, wherein the switch interface is a 2 × 2 switch element and a path through which an ATM cell is transmitted inside the switch element 403 under the control of the switch interface controller 402. Is determined. The switch interface 403 can be used for both an input switch interface or an output switch interface.

When the ATM switch system of the present invention operates in an independent operation mode in which the transmission line is independently operated without redundancy of the transmission line, if the switch interface 403 shown in FIG. 4 is used as the input switch interface 303, the input 1 is a path ( Via 441, input 2 is controlled to output to output 1 and output 2 via path 444, respectively. In addition, in the same independent operating mode, input 1 may be controlled to be output to output 2 and output 1 via path 443 and input 2 through path 442, respectively.

In addition, when the switch interface 403 is used as the output switch interface 304, in the independent operation mode, the switch interface 403 receives an input of input 1 and input 2, and the input 1 is input through a path 441. 2 is controlled to output to output 1 and output 2 via path 444, or input 1 is controlled to output to output 2 and output 1 via path 443 and input 2 to path 442, respectively. . In this case, the input switch interface controller and the output switch interface controller connected to the same transmission line board are preferably operated in the same mode.

When the ATM switch system of the present invention operates in a redundant operation mode in which a transmission line is duplicated, if the switch interface 403 shown in FIG. 4 is used as the input switch interface 303, the input 1 is routed through the path 441. Input 2 is controlled to be transmitted over path 442, and only ATM cells transmitted over either path 441 or path 442 are output to output 1. In addition, with the output terminal as the output 2, the input 1 is controlled to be transmitted through the path 443, the input 2 is transmitted through the path 444, and is transmitted through the path of either the path 443 or the path 444. Only ATM cells are output to output 2. The switch interface controller 302 controls which output terminal of the input switch interface 303 to output and which path the ATM cell transmitted through is output.

In addition, when the switch interface 403 is used as the output switch interface 304, in the redundant operation mode, the switch interface 403 receives an input through any one of an input 1 and an input 2 and transmits the input via the path 441. Outputs 1 and 2 via path 443 or through paths 442 and 444. The switch interface controller 302 controls which input terminal of the output switch interface 304 from the switching means to receive the ATM cell.

The switching means 301 receives an ATM cell from the input switch interface 303 and performs a switching operation. When the transmission line operation mode is the duplex operation mode, the switching means checks whether there is an error in the ATM cell received from the input switch interface 303, and transmits it to the switch interface controller 302 when it is determined that there is an error. Controls the cell to receive an ATM cell from a transmission line board ingress block 320b other than the transmission line board ingress block 320a to which the cell is transmitted, or if a problem occurs in the path of the input switch interface 303, an input switch. By changing the output terminal of the interface 303, the ATM cell is controlled to be input through a transmission path in which no error occurs.

The ATM cells output from the output switch interface 304 to the output 1 and the output 2 are connected to the terminal 0 333 or the terminal of the egress block 330a of the transmission line board A and the egress block 330b of the transmission line board B, respectively. Entered through 1 (334).

The egress block 320a of the transmission line board A is composed of an egress interface 331a, an egress ATM cell processor 332a, a terminal 0 333a, and a terminal 1 334a. Block 330b also includes the same components.

The egress interface 331a of the egress block 330a of the transmission line board A receives a cell inputted from the operation mode among the cells output from the two switch boards 300a and 300b and causes an error in the cell. Checks if there is no valid cell. If an error or a failure is detected, the transmission path is changed from the switch board 300a in the operation mode to the switch board 300b in the standby mode when the threshold is exceeded compared to a predetermined threshold. Such a switch board switching method has an advantage that instantaneous cell loss occurs only in the transmission path in which the exchange is performed, and does not affect the remaining normal operating transmission path.

The egress ATM cell processor 332 outputs an ATM cell input to the transmission line board egress block 330 to the outside.

5A to 5D illustrate an example in which the operation state of the ATM switch system of the present invention is described with only one switch board operating in an operation mode for simplicity of description. In other words, in FIG. 5, as shown in FIGS. 2 and 3, two switch boards are mounted, and redundancy of the switch board is basically provided, but for the sake of simplicity, only one sheet of the switch board operating in the operation mode can be used. Although the operation state of the switch system has been described, in FIG. 5, only the switch board 300a connected to the terminal 0 of the transmission line board will be described. However, the switch board 300b connected to the terminal 1 of the transmission line board also has the same function. I am doing it.

The ATM switch system of FIG. 5 includes transmission blocks 520a, 520b, 530a, and 530b having N transmission line boards on a side 520a and 530a and N transmission line boards on b side 520b and 530b. Each transmission line board is composed of one transmission line board ingress block and one transmission line board egress block. Input for receiving ATM cell from each transmission line board ingress block 520-1a, 520-2a, ... 520-na, 520-1b, 520-2b, ... 520-nb A switch interface 503, 2N x 2N or N x N switching means 501 for switching the input ATM cell, ATM cells switched in the switching means 501 each transmission line board egress block 530-1a Output switch interface 504 and input switch interface 503 and output switch interface 504 for routing to 530-2a, ... 530-na, 530-1b, 530-2b, ... 530-nb) It includes a switch board 500 having a switch interface control unit 502 for controlling the transmission line operation mode of the.

FIG. 5A illustrates a transmission path when the input switch interface and the output switch interface of the switch board 500 are set for the switch interface controller for the independent operation mode of all the transmission line boards.

Referring to one transmission path, the input switch interface 503-1 receives an ATM cell from the transmission line board ingress block 520-1a and the transmission line board ingress block 520-1b. After confirming that the current transmission line operation mode is the independent operation mode from the switch interface controller 502, the input ATM cell is output through the independent path to output the input terminal 1 and the input terminal N of the switching means 501. Send it to +1).

The switching means 501 should be of 2N x 2N form with two input terminals for each input switch interface 503 and two output terminals for each output switch interface 504. If no redundancy is required for all transmission lines as shown in FIG. 5A, each switch interface is operated in an independent operation mode and has 2N independent transmission line boards. That is, N a boards and N b boards may be connected to each switch port to perform independent transmission services.

The ATM cell input to the switching means 501 is switched in the switching means 501 and transmitted to the output switch interface of any one of the output switch interfaces 504 through a predetermined output terminal. The ATM cell transmitted to the output switch interface 504 is outputted to the outside through two transmission line board egress blocks 530 through separate paths. For example, two ATM cells are output switch interface 504-1 through two input terminals of the output terminal 1 of the switching means 501, the output terminal N + 1, and the output switch interface 504-1. When input to the ATM cell input through the output terminal (1) of the switching means 501 is output to the outside through the transmission line board egress block 530-1a, the output terminal of the switching means 501 ( The ATM cell input through N + 1) is output to the outside through the transmission line board egress block 530-1b.

FIG. 5B illustrates a transmission path when all transmission line operating modes of all transmission line boards connected to the switch board 500 are set in a redundant operation mode. That is, the a side transmission line boards are operated as a normal operation board, and the b side transmission line boards are operated in a standby mode as an extra board for the a side board. In this case, it is preferable that a pair of ingress blocks connected to the same input switch interface are connected to the same transmission line.

Referring to one transmission path, the input switch interface 503-1 receives an ATM cell from the transmission line board ingress block 520-1a and the transmission line board ingress block 520-1b. After confirming that the current transmission line operation mode is the redundant operation mode by the switch interface controller 502, the output terminal of any one of the ATM cells received from both transmission line board ingress blocks 520-1a and 520-1b. The path is set to be outputted to the terminal, and only one of the input ATM cells is transmitted to the input terminal 1 or the input terminal N + 1.

On a pair of a-side transmission line board and b-side transmission line board connected to one input switch interface and output switch interface, information related to connection setting such as routing information and traffic control parameter for transmission line redundancy is included in connection establishment. The same information is set at the same time, and the path for the actual transmission is only active on one of the two boards. The input switch interface 503-1 is set to output only one of two input points. The output switch interface 504-1 is set to output the output from the switch to one transmission line egress block.

The switching means 501 checks whether there is an error in the input ATM cell, and if there is no error, performs a switching operation and transmits to the output switch interface of any one of the output switch interfaces 504 through a predetermined output terminal. When it is determined that there is an error, the switch interface control unit 502 switches the input terminal of the input switch interface to allow the cell to be input from the transmission line operating in the standby mode. The ATM cell inputted from the transferred transmission line board is transmitted to one of the output switch interfaces 504 of the output switch interfaces 504 through a predetermined output terminal through a switching operation. For convenience, it is assumed to be input to the output switch interface 504-1.

The switched ATM cell is input to either input terminal of the output switch interface 504-1, and is activated among the transmission line board egress block 530-1a and transmission line board egress block 530-1b. It is sent to the board egress block and output to the outside. In FIG. 5B, the transmission line board is output to the outside through the transmission line board egress block 530-1a.

In FIG. 5A and FIG. 5B, the switching means 501 has a 2N x 2N form with two input terminals for each input switch interface 503 and two output terminals for each output switch interface 504, but FIG. 5B In the case of duplexing all transmission line boards as in the above, it is not necessary to have a 2N x 2N form as described above, and N x N form is sufficient. FIG. 5C shows such an embodiment. The components different from FIG. 5B are the same, and only the switching means 501 is in the form of N × N.

5A, 5B and 5C show only the case where all transmission line operating modes are set to the same mode, it is also possible to switch using different transmission line operating modes in one switch board. FIG. 5D illustrates that only the input switch interface 503-2 of the input switch interface 503 is set to the independent operation mode, the remaining input switch interfaces 503 are set to the redundant mode, and the output switch interface of the output switch interface 504. Only an example of setting 504-2 to the independent operation mode and the remaining output switch interfaces 504 to the redundant operation mode is shown.

In this way, when a system requires duplication of arbitrary transmission line boards, only the switch interface connected to the corresponding transmission line board may be operated in a redundant operation mode, and all other switch interfaces may be operated in an independent operation mode. For example, if only one transmission line is duplexed, in this case, two (N-1) transmission line boards that perform independent services, one transmission line board having an active path, and one transmission line board having a standby path Branches have one transmission line that can provide 1 + 1 redundancy. In other words, two boards are used for a transmission line supporting redundancy. Applying such variable transmission line redundancy has a transmission line board having a maximum of 1 + 1 redundancy of N. In this case, it is configured as shown in FIG. 5B, and as shown in FIG. 5C, the switching means 501 is N ×. It can be replaced by N type. If the switching means 501 is modularized and detachable to the switch board 500, an appropriate switching means 501 can be used as necessary.

In the case of variable redundancy, N transmission line boards with 1 + 1 redundancy can be mounted when using N x N switching blocks, and variable redundancy can be applied to transmission line boards when using 2N x 2N switch blocks. In this case, it is possible to apply from N transmission line board operation having 1 + 1 redundancy of all boards to independent 2N transmission line board operation without redundancy to all boards.

6 is a flowchart illustrating a method of switching an ATM cell in an ATM switch system. Referring to FIG. 3, FIG. 6 is as follows.

When data is input, the input data is converted into an ATM cell by the ingress ATM cell processor 322 of the transmission line board ingress block 320 (610). The converted ATM cell is copied from the ingress interface 321 and transmitted to the input switch interfaces 303a and 303b (620).

Referring to the switch board 300a in the operation mode, the input switch interface 303a checks the transmission line operation mode from the switch interface controller 302a (630), and in the redundant operation mode (mode 1), the transmission line. Only one ATM cell input from the board ingress block A 320a and the transmission line board ingress block B 320b is transmitted to the switching means 301a to perform a switching operation (631). When it is determined 633 that there is an error in the ATM cell inputted to the switching means 301a, the switch interface controller 302a determines from the transmission line board ingress block other than the transmission line board ingress block to which the ATM cell is transmitted. The transmission path is changed to receive an ATM cell (634) so that the ATM cell is input through the transmission path in which no error occurs.

When the identified transmission line operating mode is the independent operation mode (mode 2), the ATM cells inputted from the transmission line board ingress block A 320a and the transmission line board ingress block B 320b are switched through independent paths, respectively. Perform (632)

The switched ATM cell is transmitted 640 to the transmission line board egress blocks 330a and 330b via an output switch interface 304a. Assuming transmission line board A is activated, egress interface 331a of transmission line board egress block A 330a is connected to the ATM cell inputted through terminal 0 333a from switch board 300a in the operation mode. If there is no error (650), and if there is no error, the ATM cell is output to the outside (661). If it is determined that an error has occurred, it is input through the terminal 1 (333b) from the switch board 300b in the standby mode. The ATM cell is output to the outside (662).

The method of the present invention can also be embodied as computer readable code on a computer readable recording medium. The computer-readable recording medium includes all kinds of recording devices in which data that can be read by a computer system is stored. Examples of computer-readable recording media include ROM, RAM, CD-ROM, magnetic tape, floppy disk, optical data storage, and the like, and may also be implemented in the form of a carrier wave (for example, transmission over the Internet). Include. The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion.

According to the ATM switch system and method according to the present invention as described above

First, the present invention has the effect of adding the variable redundancy function of the transmission line board while having the same redundancy function of the existing switch board by using the switch interface element.

Second, the present invention provides the variability in the transmission line board redundancy to use only when redundancy is necessary, and when redundant is not necessary, an extra board for redundancy can be operated independently to reduce the transmission cost of the system. Have

Third, the present invention has the effect of reducing the cost of expansion of the switch board by modularizing the switching means so that only the modules corresponding to the switching means can be replaced without changing the circuit when the switching means are replaced.

Although shown and described with respect to specific preferred embodiments of the invention above, it is understood that the present invention may be variously modified and changed within the scope of the technical idea of the present invention provided by the claims below. Those skilled in the art will readily know.

Claims (17)

Switching means for performing switching by receiving an Asynchronous Transfer Mode (ATM) cell; An input switch interface for receiving the ATM cell through a plurality of paths and transmitting the received ATM cell to the switching means; An output switch interface for receiving the switched ATM cells from the switching means and outputting them externally; And The first mode in which only ATM cells input via any one of the ATM cells received at the one input switch interface are transmitted to the switching means, or the ATM cells received at the one input switch interface are the switching means. Switch interface control unit for controlling to be transmitted in any one of the second mode state transmitted through each independent path in the ATM switch system comprising a variable redundancy of the transmission path. The system of claim 1, wherein the ATM switch system comprises at least two switch modules including the switching means, the input switch interface, the output switch interface, and the switch interface controller. ATM switch system available. The method of claim 1, wherein the ATM switch system And a plurality of ingress transmission line modules for converting data input from the outside into the ATM switch system to the ATM cell and transmitting the data to the input switch interface. The system of claim 2, wherein the ATM switch system An ATM capable of variable duplication of transmission paths, further comprising an egress transmission line module for transmitting an ATM cell input from one switch module of the ATM cells input from the plurality of switch modules to the outside. Switch system. The transmission path according to any one of claims 1 to 4, wherein the switch interface controller controls some of the ATM cells to be transmitted in the first mode and others to the second mode. ATM switch system with variable redundancy. 6. The ATM switch system of claim 5, wherein the ratio of the ATM cells transmitted in the first mode and the ATM cells transmitted in the second mode is variable. The switch module of claim 2, wherein one switch module of the plurality of switch modules operates in an operation mode for substantially switching transmission of the ATM cell, and the other switch module generates an error in the switch module operating in the operation mode. An ATM switch system capable of variable redundancy of a transmission path, characterized by operating in a standby mode waiting for a case. The ingress interface unit of claim 3, wherein the ingress transmission line module copies the ATM cells from the outside into the same plurality of ATM cells and transmits the copied identical ATM cells to each of the plurality of switch modules. ATM switch system capable of variable redundancy of the transmission path comprising a. 9. The transmission of claim 3 or 8, wherein the ingress transmission line module further comprises an ingress ATM cell processor for converting data input from the outside into the ATM switch system into an ATM cell. ATM switch system with variable redundancy of paths. The method of claim 4, wherein the Egress transmission line module Among the ATM cells input from the plurality of switch modules, an ATM cell inputted from a switch module operating in an operation mode is checked for errors, and if there is no error, an ATM cell input from the switch module operating in the operation mode is checked. And an ATM cell inputted from the switch module operating in the standby mode to the outside, and transmitting to the outside if an error exists. 5. The variable transmission path according to any one of claims 1 to 4, wherein the switching means comprises at least two input terminals for each of the input switch interfaces and at least two output terminals for each of the output switch interfaces. Redundant ATM switch system. A method for switching an ATM cell in an ATM switch system, (a) receiving data input through a plurality of transmission line modules in an ingress module; (b) converting the input data into an ATM cell in the ingress module; (c) copying the converted ATM cell from the ingress module and inputting the copied ATM cell into a plurality of different switch modules; (d) checking whether an error has occurred in an ATM cell input from a first transmission line module among ATM cells inputted from the plurality of transmission line modules to the plurality of switch modules in the switch module; (e) if the switch module determines that no error has occurred in the ATM cell checked in step (d), switching the inspected ATM cell; (f) If the switch module determines that an error has occurred in the ATM cell checked in step (d), it is checked whether an error exists in the ATM cell inputted from the transmission line module except the first transmission line module. Switching ATM cells that are determined to be absent; (g) checking whether an error has occurred in an ATM cell switched in a first switch module among the ATM cells switched in the different switch module in an egress module; (h) outputting the checked ATM cell to the outside when the egress module determines that an error has not occurred in the ATM cell checked in the step (g); And (i) if it is determined that an error occurs in the ATM cell checked in the step (g) in the egress module, outputting the switched ATM cell to the outside from the switch module except the first switch module; Method for switching an ATM cell capable of variable redundancy of the transmission path, characterized in that. A method for switching an ATM cell in an ATM switch system, (a) receiving a plurality of ATM cells through different paths in a switch module; (b) confirming a transmission line operation mode in the switch module; (c) in the switch module, when the transmission line operation mode identified in step (b) is the first mode, switching only the ATM cells input through any one of the ATM cells input through the different paths; step; And (d) in the switch module, when the transmission line operation mode identified in step (b) is the second mode, switching ATM cells input through the different paths through independent paths to each other; Method for switching an ATM cell capable of variable redundancy of the transmission path, characterized in that. The method of claim 13, wherein the switching of the ATM cell is performed before the step (a). (a-1) converting the input data into an ATM cell; And (a-2) copying the converted ATM cells and inputting the copied identical ATM cells to different switch modules, respectively; switching the ATM cells capable of variable duplication of transmission paths, further comprising: Way. 15. The method of claim 14 wherein the method of switching the ATM cell is (e) checking whether an error has occurred in an ATM cell switched in a first switch module among the ATM cells switched in the different switch modules; (f) if it is determined that no error occurs in the ATM cell checked in step (e), outputting the checked ATM cell to the outside; And (g) if it is determined that an error occurs in the ATM cell checked in step (e), outputting the switched ATM cell from the switch module except the first switch module to the outside; A method for switching ATM cells capable of variable redundancy of transmission paths. The method of claim 13, wherein step (c) (h) checking whether an error has occurred in an ATM cell input through a first path among the different paths input to the switch module; (i) if it is determined that no error occurs in the ATM cell checked in step (h), switching the inspected ATM cell; (j) If it is determined that an error has occurred in the ATM cell checked in step (h), it is determined whether there is an error in the ATM cell inputted from the path except the path designated as the first path, and the ATM is determined to have no error. Switching a cell; and a method for switching an ATM cell capable of variable redundancy of a transmission path. A computer-readable recording medium having recorded thereon a program for realizing the method according to any one of claims 12 to 16.