KR100334803B1 - Cell copy device and method in an atm communication system having the utopia interface for cell transmission between nodes - Google Patents

Abstract

An ATM communication system is disclosed that includes one utopian interface master board for cell-to-node cell transmission and a plurality of utopian interface slave boards. In the present invention, when the destination is the same and may receive the same VPI / VCI, the input cell is copied to at least two slave boards and transmitted. The cell copy apparatus of the present invention includes a memory that stores a destination port value in correspondence with each of a series of addresses. The address extractor extracts VPI / VCI from the header included in the input cell and outputs the address as an address for accessing the memory. The cell transmitter copies and transmits the input cell to at least two slave boards designated by the stored destination port value corresponding to the accessed address. The memory, address extraction section and cell transfer section are mounted in a master board.

Description

CELL COPY DEVICE AND METHOD IN AN ATM COMMUNICATION SYSTEM HAVING THE UTOPIA INTERFACE FOR CELL TRANSMISSION BETWEEN NODES}

The present invention relates to an ATM system, and more particularly, to a cell copying apparatus and method of an AT communication system having a utopia interface for inter-node cell transmission.

In general, a mobile communication system such as an IMT-2000 system using a code division multiple access (CDMA) scheme includes a base station system (BSS) and a mobile switching center (MSC). do. The BSS may be classified into a base station controller (BSC) and a base transceiver subsystem (BTS). Such mobile communication systems are being implemented based on Asynchronous Transfer Mode (ATM) to improve the efficiency of the use of a plurality of physical links and the use of channel bandwidth.

The ATM Forum has already determined the inter-node cell transmission specification, ie, physical layer specifications, in an ATM-based mobile communication system (hereinafter referred to as an 'ATM communication system'). The cell transmission standard of the determined physical layer specification includes the 155 Mbps ATM Physical Medium Dependent Interface (Unshielded Twisted Pair (UDP) -5 copper wiring), DS1 (the 1.544 Mbps) physical layer interface, and UTOPIA (the Universal). Test and Operation PHY Interface for ATM) interface. The utopia interface is for an interface between a physical layer and a higher layer such as ATM modules. Initially, starting from UTOPIA L1 (Level 1), the UTOPIA L2 is already defined. The utopia interface L1 is a 1: 1 cell transmission standard, and the utopia interface L2 is a 1: n cell transmission standard.

In order to enable an ATM communication system that maps an ATM cell to a format that conforms to a specific transmission standard through a physical transmission medium and transmits it between nodes, a virtual connection (VC) may be used. It is necessary to set as many Virtual Path Identifiers / Virtual Channel Identifiers (VPI / VCI) as the number of subscribers. According to these needs, in ATM communication system using Utopia interface for inter-node transmission Even in the case of multicasting, ATM cells going to each node in the multicast group have different VC-VPI / VCI.

Meanwhile, in an ATM communication system using a utopia interface for inter-node transmission, a simple cell copy function is not considered at all when considering a method of transmitting and serving cells. Here, the simple cell copy function refers to a function of copying two or more untranslated ATM cells having the same VPI / VCI. In other words, the ATM Forum has decided on the utopia interface that can be used when transmitting ATM cells through a physical transmission medium, but has not decided on the fact that the cell copy function can be performed in the manner of transmitting a cell using the utopia interface. none. This decision is based on no prediction of the case where the same destination and the same VPI / VCI may be received within the system.

However, when implementing an ATM communication system that actually uses a utopia interface for inter-node transmission, there are cases where the same destination and the same VPI / VCI may be received. For example, in an ATM communication system, it is desirable to structure the processor block in a redundant manner in order to stabilize the system, and this duplication structure corresponds to a case where the destination is the same and may receive the same VPI / VCI. Therefore, if the cell copy function is performed when the destination is the same in the ATM communication system and may receive the same VPI / VCI, resources in the system including the VPI / VCI may be saved. In addition, if a cell copy function is to be performed, it may support the operation of a block requiring real-time duplication.

Accordingly, an object of the present invention is to provide an apparatus and method for cell copying when transmitting a cell between nodes in an ATM communication system having a utopia interface.

Another object of the present invention is to provide an apparatus and method for saving system resources in an ATM communication system having a utopia interface for inter-node cell transmission.

It is still another object of the present invention to provide an apparatus and method for supporting an operation of a block requiring real-time duplication in an ATM communication system having a utopia interface for inter-cell cell transmission.

In order to achieve these objects, the present invention provides a case in which an ATM communication system having one utopian interface master board for inter-node cell transmission and a plurality of utopian interface slave boards may receive the same VPI / VCI at the same destination. It is a cell copying apparatus that copies and transmits a cell to at least two slave boards.

The cell copying apparatus according to the first aspect of the present invention includes a memory that stores destination port values in correspondence with a series of addresses. The address extractor extracts VPI / VCI from the header included in the input cell and outputs the address as an address for accessing the memory. The cell transmitter copies and transmits the input cell to at least two slave boards designated by the stored destination port value corresponding to the accessed address. The memory, address extraction section and cell transfer section are mounted in a master board.

The cell copying apparatus according to the second aspect of the present invention includes a memory that stores corresponding destination port values for designating slave boards having a redundant structure in each of a series of addresses. The address extractor extracts VPI / VCI from the header included in the input cell and outputs the address as an address for accessing the memory. The cell transmitter transmits an enable signal to two slave boards designated by the stored destination port value corresponding to the accessed address, and copies the input cell to the slave boards having a redundancy structure by transmitting the input cell. To transmit. And the memory, address extraction unit and cell transfer unit are mounted in a master board.

1 is a block diagram of a UTOPIA interface device to which the present invention is applied.

2A and 2B illustrate signals transmitted and received at the utopia interface device shown in FIG. 1.

3 is a block diagram of a cell copying apparatus according to the present invention;

4 illustrates a cell copy operation according to an embodiment of the present invention.

5 is a diagram illustrating a cell copy operation according to another embodiment of the present invention.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. In the following description of the reference numerals to the components of the drawings, it should be noted that the same reference numerals as much as possible even if displayed on different drawings. In addition, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are defined in consideration of functions in the present invention, which may vary according to the intention or custom of the user or chip designer, and the definitions should be made based on the contents throughout the present specification.

First, it should be noted that the present invention is applied to a UTOPIA interface device as shown in FIG. The utopia interface device is provided for cell-to-node cell transmission in an ATM communication system, and may be applied to an ATM terminal, an ATM switch subscriber matching unit, an ATM switch core, and the like. The Utopia interface device includes one Utopia Interface (I / F) Master Board 100 and a plurality of Utopia Interface Slave Boards 200 to n (# 0 to # n-1). 290 is provided. In the following description, the utopia interface master board is referred to as a master board, and the utopia slave board is referred to as a slave board. The case where the number n of the slave boards is 10 will be described.

2A and 2B illustrate signals transmitted and received between the master board 100 and the slave boards 200 to 290 illustrated in FIG. 1. In this case, the transmitting operation refers to an operation of transmitting a signal from the master board 100 to the slave boards 200 to 290, and the receiving operation is an operation of transmitting a signal from the slave boards 200 to 290 to the master board 100 so that the master board 100 receives the signal. it means.

2A and 2B, RxData (8: 0) is data transmitted from the slave boards 200 to 290 to the master board 100 and received at the master board 100. TxData (8: 0) is data transmitted from the master board 100 to the slave boards 200 to 290. RxClav # 0 to # (n-1) is a signal indicating that a cell to be transmitted to the slave board 200 to 290 and available to the master board 100 is available, and is transmitted from the slave boards 200 to 290 to the master board 100. TxClav # 0 to # (n-1) are signals indicating that a cell transmitted from the master board 100 to the slave boards 200 to 290 is valid, and is transmitted from the slave boards 200 to 290 to the master board 100. RxEnb # 0 to # (n-1) are reception enable signals provided by the master board 100 to the slave boards 200 to 290 to enable the reception operation. TxEnb # 0 to # (n-1) are the transmit enable signals provided by the master board 100 to the slave boards 200 to 290 to enable the transmission operation. RClk # 0 to # (n-1) is a reception clock provided by the master board 100 to the slave boards 200 to 290 for a reception operation.

In the above description, RxClav # 0 to # (n-1) and TxClav # 0 to # (n-1) are signals representing the states of the slave boards 200 to 290. RxEnb # 0 to # (n-1) and TxEnb # 0 to # (n-1) are signals for controlling the slave boards 200 to 290. As such, the state signal and the control signal are provided for each of the slave boards so that cell copying can be simultaneously performed on at least two slave boards. For reference, as already mentioned, the utopia interface L1 is a 1: 1 cell transmission standard, that is, a standard for transmitting cells between one master board and a slave board, and the utopia interface L2 is a 1: n cell transmission standard, that is, This is the standard when a cell is transferred between one master board and n slave boards. The Utopia interface L2 follows a direct status polling method for up to four slave boards and an address polling method for more slave boards. In contrast, the Utopia interface device according to the present invention has a difference in that the cell copy function is simultaneously performed while directly polling status regardless of the number of slave boards.

3 is a view showing the configuration of a cell copying apparatus according to the present invention.

Referring to FIG. 3, the address extractor 110 receives an input cell stream, extracts a VPI / VCI from a header included in an input cell, and stores the extracted VPI / VCI in memory. 120 is output as an address for accessing. The memory 120 has a series of addresses, each of which is stored with a corresponding destination port value. In this case, the destination port value represents a port provided at the output terminal of the master board 100 for connection with the slave boards 200 to 290, and as a result, a slave board is designated. At this time, at least two destination port values are stored in one address. The cell transmitter 130 receives the stored destination port value corresponding to the address accessed and output from the memory 120, and copies and transmits the input cell to the slave board designated by the received destination port value. The input cell may be transmitted to at least two slave boards by a cell copy operation by the cell transmitter 130. While searching for a destination port (slave board) for an input cell in the memory 120, the input cell is internally delayed for a predetermined time, and if the destination port is found, the delayed input cell is transmitted to the corresponding slave board.

The cell copy operation according to the present invention is performed by the cell transmitter 130 controlling the transmit enable signals TxEnb # 0 to # (n-1). That is, the cell transmitter 130 receives the destination port value from the memory 120 and checks the designated slave board. The cell transmitter 130 transmits the enable signal to the confirmed slave board and transmits the input cell and at least two slave boards. Allow the cell copy operation to be performed. For example, the input cell may be copied and transmitted to two slave boards by the cell copy operation according to the present invention. This example may be useful when the slave board has a redundant structure. As another example, the input cell may be copied and transmitted to all slave boards by the cell copy operation according to the present invention. This example can be useful when testing all slave boards.

Table 1 below shows the structure of the memory 120 according to an example of transmitting a simple cell, that is, transferring a cell to the slave boards 200 to 290 without copying an input cell. <Table 2> shows the structure of the memory 120 according to an example of copying and transmitting an input cell to two redundant redundant slave boards. <Table 3> shows the structure of the memory 120 according to an example of copying and transmitting an input cell to eight slave boards.

division Destination Port ID (4: 0) Simple cell transfer MID PID (3) PID (2) PID (1) PID (0) Address 0 0 0 0 0 0 Port ID 0 (Slave 0) Address 1 0 0 0 0 One Port ID 1 (Slave 1) Address 2 0 0 0 One 0 Port ID 2 (Slave 2) Address 3 0 0 0 One One Port ID 3 (Slave 3) Address 4 0 0 One 0 0 Port ID 4 (Slave 4) Address 5 0 0 One 0 One Port ID 5 (Slave 5) Address 6 0 0 One One 0 Port ID 6 (Slave 6) Address 7 0 0 One One One Port ID 7 (Slave 7) Address 8 0 One 0 0 0 Port ID 8 (Slave 8) Address 9 0 One 0 0 One Port ID 9 (Slave 9)

division Destination Port ID (4: 0) Concurrent Cell Copy Transfer MID PID (3) PID (2) PID (1) PID (0) Address 0 One 0 0 0 0 Port ID 0 & 1 (Slave 0 & 1) Address 1 One 0 0 One 0 Port ID 2 & 3 (Slave 2 & 3) Address 2 One 0 One 0 0 Port ID 4 & 5 (Slave 4 & 5) Address 3 One 0 One One 0 Port ID 6 & 7 (Slave 6 & 7) Address 4 One One 0 0 0 Port ID 8 & 9 (Slave 8 & 9)

division Destination Port ID (4: 0) Concurrent Cell Copy Transfer MID PID (3) PID (2) PID (1) PID (0) Address One One One One One Port ID 0 ~ 7 (Slave 0 ~ 7)

In Tables 1, 2, and 3, the MID is an ID representing a cell copy transmission, that is, a multicast ID, and the PID is a port ID. For example, when the destination port ID is '00000', the cell transmitter 130 transmits the input cell to the slave board # 0 200 having the port ID 0 without a copy operation, and when the destination port ID is '00100', the port ID 4 The input cell is transmitted to the slave board # 4 240 without a copy operation, and when the destination port ID is '01001', the input cell is transmitted to the slave board # 9 290 having the port ID 9 without the copy operation. As another example, when the destination port ID is '10000', the cell transmitter 130 simultaneously copies the input cells to the slave boards # 0 and # 1 200,210 having the port ID0,1, and simultaneously transmits them. The destination port ID is '10110'. Copy the input cell to Slave board # 6, # 7 260,270 with port ID 6,7 and transmit it simultaneously. As another example, when the destination port ID is '11111', the cell transmitter 130 copies the input cells to the slave boards # 0 to # 7 200 to 270 having the destination port IDs 0 to 7 and simultaneously transmits them.

4 is a diagram illustrating a cell copy operation according to an embodiment of the present invention, and corresponds to a case in which the memory 120 is structured as shown in Table 2 above.

Referring to FIG. 4, the slave board 200 and the slave board 210 have a redundant structure, the slave board 220 and the slave board 230 have a redundant structure, and the slave board 240 and the slave board 250 have a redundant structure. The slave board 270 has a redundant structure, and the slave board 280 and the slave board 290 have a redundant structure. When a cell is input to one slave board, a transmit enable signal is applied to the corresponding slave board in order to simultaneously copy and transmit the cell to another board having a redundant structure. When the cell A is input, the transmit enable signals TxEnb # 0 and TxEnb # 1 are provided to the slave boards 200 and 210, respectively. When the cell B is input, the transmit enable signals TxEnb # 2 and TxEnb # 3 are provided to the slave boards 220 and 230, respectively. When the cell C is input, the transmit enable signals TxEnb # 4 and TxEnb # 5 are provided to the slave boards 240 and 250, respectively. When the cell D is input, the transmit enable signals TxEnb # 6 and TxEnb # 7 are provided to the slave boards 260 and 270, respectively. When the cell E is input, the transmit enable signals TxEnb # 8 and TxEnb # 9 are provided to the slave boards 280 and 290, respectively. The transmit enable signals TxEnb # 0 to TxEnb # 9 are provided by the cell transmitter 130 of FIG. 3.

5 is a diagram illustrating a cell copy operation according to another exemplary embodiment of the present invention, and corresponds to a case in which the memory 120 is structured as shown in Table 3 above.

Referring to FIG. 5, the input cell is copied by the cell transmitter 130 and simultaneously transmitted to the slave boards 0 to 7 200 to 270. For the cell copy and transmit operation, the cell transmitter 130 provides the transmit enable signals TxEnb # 0 to TxEnb # 7 to the slave boards 200 to 270. That is, the cell transmitter 130 provides each of the transmit enable signals TxEnb # 0 to TxEnb # 7 to the slave boards 200 to 270 to transmit the same cell to the slave boards 200 to 270.

As described above, the present invention has the advantage of saving resources in the system including the VPI / VCI by performing the cell copy function when the destination is the same and may receive the same VPI / VCI in the ATM communication system. In addition, if the cell copy function is to be performed, there is an advantage that can support the operation of the slave board having a redundancy structure, which is a block requiring real-time redundancy.

Meanwhile, in the detailed description of the present invention, specific embodiments have been described, but various modifications are possible without departing from the scope of the present invention. Therefore, the scope of the present invention should not be limited to the described embodiments, but should be determined not only by the scope of the following claims, but also by the equivalents of the claims.

Claims (9)

In the cell copy apparatus of the ATM communication system having a utopia interface master board for cell transmission between nodes and a plurality of utopia interface slave board, A memory that stores destination port values in correspondence with a series of addresses, An address extraction unit for extracting a VPI / VCI from a header included in an input cell and outputting the VPI / VCI as an address for accessing the memory; And a cell transmitter for copying and transmitting the input cells to at least two slave boards designated by a stored destination port value corresponding to the accessed address, wherein the cell copy apparatus is mounted on the master board. The apparatus of claim 1, wherein the cell transmitter transmits an enable signal to a slave board designated by a destination port value stored corresponding to the accessed address, and transmits the input cell to the at least two slave boards. A cell copying apparatus, characterized in that for copying and transmitting a cell. The method of claim 1, wherein the plurality of slave boards have a redundancy structure, boards having a redundancy structure are designated to one destination port value, and the input cells are simultaneously copied to the slave boards having the redundancy structure. Cell copy device. 2. The cell copy apparatus of claim 1, wherein all of the plurality of slave boards are designated to one destination port value, and the input cells are simultaneously copied to all slave boards. In the cell copy apparatus of the ATM communication system having a utopia interface master board for cell transmission between nodes and a plurality of utopia interface slave boards having a redundant structure, A memory that maps and stores a destination port value that designates slave boards having a redundant structure in each of a series of addresses; An address extraction unit for extracting a VPI / VCI from a header included in an input cell and outputting the VPI / VCI as an address for accessing the memory; The enable signal is transmitted to two slave boards designated by the stored destination port value corresponding to the accessed address, and the input cell is copied to the slave boards having a redundant structure by transmitting the input cell. And a cell transfer unit, wherein they are mounted on the master board. In the cell copy method of the ATM communication system having a utopia interface master board for transmitting the cells between nodes and a plurality of utopia interface slave board, Storing the destination port values in memory in correspondence with each of the series of addresses; Extracting a VPI / VCI from a header included in an input cell and outputting the VPI / VCI as an address for accessing the memory; And copying and transmitting the input cells to at least two slave boards designated by the stored destination port value corresponding to the accessed address. The method of claim 6, wherein the input cell transmission process comprises: enabling an at least two slave boards by transmitting an enable signal to a slave board designated by a stored destination port value corresponding to the accessed address, and transmitting the input cell. And copying and transmitting the input cell. 7. The method of claim 6, wherein slave boards having a redundant structure are designated to one destination port value, and the input cell is simultaneously copied to slave boards having a redundant structure. 7. The method of claim 6, wherein all of the plurality of slave boards are assigned to one destination port value, and the input cells are simultaneously copied to all slave boards.