KR100353714B1 - Dual switching method between rt/qrt cell data - Google Patents

Abstract

In the redundant switching method between the RT cell and the QRT cell in the switching board redundancy apparatus, a process of restricting the input of the RT cell data by generating an input limit signal to the RT interface when a switch over signal is generated, and limiting the RT cell data input After the signal is generated, checking whether the memory of the RT2QRT cell converter is in an empty state, and if the memory of the RT2QRT cell converter is in an empty state, generating an input restriction signal to a QRT interface to restrict input of QRT cell data. Checking whether the QRT unit and the QSE unit have an empty state after the QRT cell data input limit signal is generated; and if the QRT unit and the QSE unit have an empty state, the master right of the active switch board is turned on. It is characterized by the configuration including the process of switching to the board.

Description

DUAL SWITCHING METHOD BETWEEN RT / QRT CELL DATA}

The present invention relates to the implementation of an asynchronous transmission mode switching board, and more particularly, to a redundant switching method between an RT cell and a QRT cell.

Normally, the system doubles the common parts of the system to improve the stability. The board implementing the redundancy includes a switching board, a clock board providing clock synchronization, and a process board. Switching boards using QSE are basically implemented to interface with boards using QRT.

Accordingly, there is a problem that a separate cell converter is required to switch the cells coming from the board using the conventional RT.

Accordingly, an object of the present invention is to provide a redundant switching method between RT / QRT cell data that enables switching over without losing a cell currently being serviced in a switch board that simultaneously switches an existing RT cell and a QRT cell.

The present invention for achieving the above object in the redundant switching method between the RT cell and the QRT cell in the switching board redundancy device, the process of limiting the input of the RT cell data by generating an input limit signal to the RT interface when the switch over signal occurs; And checking whether the memory of the RT2QRT cell converter is empty after generating the RTcell data input limit signal, and generating an input limit signal through a QRT interface if the memory of the RT2QRT cell converter is empty. Limiting data input; checking whether the QRT and QSE memories are empty after generating the QRT cell data limit signal; and if the QRT and QSE memories are empty, an active switch It comprises a process of converting the master master of the board to the standby switch board.

1 is a block diagram of a switching board redundancy apparatus according to an embodiment of the present invention;

FIG. 2 is a detailed internal block diagram of the controller of FIG. 1;

3 is a process flow diagram for redundant switching between RT / QRT cell data according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. Many specific details are set forth in the following description and in the accompanying drawings, in order to provide a more thorough understanding of the present invention. It will be apparent to those skilled in the art that the present invention may be practiced without these specific details. And a detailed description of known functions and configurations that may unnecessarily obscure the subject matter of the present invention will be omitted.

1 is a block diagram of a switching board redundancy apparatus according to an exemplary embodiment of the present invention, and FIG. 2 is a block diagram illustrating a detailed block configuration of the controller 106 of FIG. Hereinafter, the operation of each part of the switching board redundancy apparatus according to the embodiment of the present invention will be described with reference to FIGS. 1 and 2. First, the error detector 108 detects a board disconnection, reset from the NMS, and an abnormal clock that may occur in the switching board, and informs the controller 106 of the operation of switching over. The RT input limit signal (BP) generating unit 204 prevents the RT2QRT cell conversion unit 104 from sending cell data to the RT by the control of the control logic unit 214 according to the reception of the switching over request signal. Generate the input limit signal BP. At this time, when the input limit signal (BP) is generated, the RT side transmits only the cell currently being transmitted, and stops transmission from the next cell. Since the QRT RX-FIFO state inspection unit 200 does not have a signal to inform the QRT itself whether or not there is data in the internal memory, the QRT RX-FIFO state inspection unit 200 checks the data line sent from the QRT unit 102 to the QSE unit 100, If the data line does not change during the time, it is determined that there is no data in the QRT, and informs the control logic unit 214.

Since the QSE input limit signal control unit 206 is provided with an input pin that allows the QSE unit 100 to generate an input limit signal from outside, the QSE unit 100 generates a signal of a specific pattern on the input pin. Generate an input limit signal. When there is no data in the memory, the QSE memory checker 208 checks a signal of a specific pattern generated from the QSE unit 100 to inform that there is no data in the QSE. Since the QRT TX-FIFO state inspection unit 210 does not have a signal to inform the QRT itself whether there is data in the internal memory, the data transmitted from the QRT unit 102 to the RT2QRT cell conversion unit 104 is QRT. In order to check whether the memory in the unit 102 is no longer present, the data enable signal of the external utopia signal is examined and if there is no change for a predetermined time, it is determined that there is no data in the QRT. Notified to control logic unit 214. The RT2QRT TX-FIFO state inspection unit 212 checks whether all the data in the RT2QRT cell conversion unit 104 has been transmitted to the RT interface board and notifies the control logic unit 214.

3 illustrates an operation control flow for implementing redundant switching between an RT cell and a QRT cell in a switching board duplication apparatus according to an exemplary embodiment of the present invention. Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1, 2, and 3.

First, an error is detected from the error detection unit 108 that periodically checks the state of the switching board, and a switching over signal for generating a master right of the active switching board to a board currently operating in standby mode is generated. In this case, the control logic unit 214 proceeds to step 302 in response to step 300 and applies a control signal for generating an input limit signal (BP) to the RT interface. Accordingly, the RT2QRT input limit signal (BP) generator 204 generates an input limit signal so that no more cell data is received from the RT side. The control logic unit 214 proceeds to step 304 to check whether the RX-FIFO in the RT2QRT cell conversion unit 104 is empty through the RT2QRT RX-FIFO state inspection unit 202.

At this time, if the RX-FIFO in the RT2QRT cell conversion unit 104 is in an empty state, the control logic unit 214 proceeds to step 306 and again whether the RX-FIFO in the QRT unit 102 is in an empty state. Check it. At this time, the cell received by the RT2QRT cell converter 104 is once stored in the memory in the QRT unit 102. In the QSE memory checker 208, the 4-bit nibble is connected from the QRT unit 102 to the QSE unit 100. When the upper 4 bits and 3 bits of the data are continuously examined and the data of the header content of the cell is found to be valid, the data is determined to be no longer transmitted to the QSE unit 100 in the QRT. 214). Then, the control logic unit 214 recognizes that the RX-FIFO in the QRT unit 102 is empty according to the response from the QSE memory checker 208, and generates a control signal for generating a QRT input limit signal to the QRT interface. Apply. At this time, as in the step (302), the input limit signal should be generated so that no more cell data is received to the QRT side, but the QSE input signal controller 206 is required to generate an input limit signal from the QSE unit 100. Create and apply. Accordingly, the QSE unit 100 generates a QRT input restriction signal so that no more QRT cell data is received in step 308.

The control logic unit 214 proceeds to step 310 to check whether the QSE RX / TX-FIFO is empty by the QSE memory checker 208. In the state where all cell data received by the QSE unit 100 is blocked, the QSE unit 100 notifies whether the cell data remains in the outside as serial data of a specific pattern, and the QSE memory inspection unit 208. ) Receives the data and the memory in the QSE unit 100 recognizes the current empty state and notifies the control logic unit 214. If the QSE RX / TX-FIFO is empty in step 310, the control logic unit 214 proceeds to step 312 in response to checking the memory state in the QRT at the utopian interface between the QRT and the RT2QRT. That is, if the data is maintained in the deassert state for a predetermined time by using the data enable signal among the utopia interface signals, it is determined that there is no data in the internal memory of the QRT unit.

At this time, if it is recognized that the QRT TX-FIFO is in an empty state, the control logic unit 214 proceeds to step 314 and the data received from the QRT unit 102 through the RT2QRT TX-FIFO state checking unit 212 is again returned. The RT2QRT cell converter 104 transmits all the data to RT to determine whether the RT2QRT TX-FIFO is empty. Subsequently, when the control logic unit 214 determines that the RT2QRT TX-FIFO is empty, the control logic unit 214 transfers the master right of the current active switch board to the standby redundancy board in step 316 to perform the switch board switching over.

As described above, the present invention increases the compatibility between the ATM switching board and the subscriber board by applying a duplication algorithm in the board that simultaneously switches the conventional RT cell and the QRT cell without loss of the ATM cell in service. This has the advantage of enabling an efficient and stable system.

Claims (3)

In a redundant switching method between an RT cell and a QRT cell in a switching board duplexer, Limiting the input of RT cell data by generating an input limit signal through the RT interface when a switch over signal is generated; Checking whether the memory of the RT2QRT cell converter is empty after generating the RT cell data limit signal; Limiting input of QRT cell data by generating an input limit signal through a QRT interface when the memory of the RT2QRT cell converter is empty; Checking whether an empty state of the memory in the QRT unit and the QSE unit is generated after the QRT cell data input limit signal is generated; And switching the master rights of the active switch board to the standby switch board when the memories in the QRT unit and the QSE unit are empty. The method of claim 1, wherein the memory state checking of the RT2QRT cell conversion unit comprises: Checking whether the received RT cell data exists in the RX-FIFO of the RT2QRT cell converter after generating the RT cell data limit signal; If the received RT cell data does not exist in the RX-FIFO in the RT2QRT cell converter, it checks the memory in the QRT unit and checks whether all the cell data received from the RT2QRT cell converter is transmitted to the QSE unit. Redundant Switching Method The process of claim 1, wherein the memory state checking process of the QSE unit comprises: Checking whether the received QRT cell data exists in the QSE memory after generating the QRT cell data limit signal; And if the received QRT cell data does not exist in the QSE unit memory, checking whether the QRT cell data transmitted from the QSE unit exists in the QRT unit memory.