KR0132939B1 - Method and apparatus for checking oam cell of virtual - Google Patents

Abstract

The present invention is OAM (Operation) used for the purpose of operation maintenance of virtual paths and virtual channels in the ATM (Asynchronous Transfer Mode) VP / VC (Virtual Path / Virtual Channel) exchange system that can process the virtual channel and the virtual path at the same time The present invention relates to an apparatus and a method for distinguishing OAM cells in an ATM VP / VC switching system for cell separation.F4, which depends on the role of the VP / VC exchange as well as the distinction between the virtual channel and the virtual path, which are exchange units, For the processing of the F5 OAM cell, there is an effect of distinguishing the role (VP link connection point or VPC endpoint) on the virtual path of the VP / VC switch and the role on the virtual channel (VC link connection point or VCC endpoint).

Description

Apparatus and method for distinguishing OAM cells in ATM virtual path / virtual channel exchange system

1 is a diagram illustrating an OAM cell flow in a virtual channel and a virtual path, FIG. 2 is a diagram illustrating a configuration of a conventional VP and VC switch, and FIG. 3 is a diagram of a header processor for classifying OAM cells according to the present invention. 4 is a configuration example of the PTI search means, FIG. 5 is a configuration example of the VCI search means, FIG. 6 is a configuration example of the existing VPI / VCI search means, and FIG. 7 is a configuration example of the VPI / VCI search means of the present invention. FIG. 8 is a diagram illustrating the configuration of the existing VPI search means, FIG. 9 is a diagram illustrating the configuration of the VPI search means according to the present invention, and FIG. 10 is a diagram illustrating the configuration of the end-to-end F5 OAM tester according to the present invention. Fig. 12 is a view illustrating the configuration of the segment F5 OAM tester according to the present invention, and Fig. 12 is a view illustrating the configuration of the end-to-end F4 OAM tester according to the present invention. OAM cell discrimination processing flow chart.

The present invention is OAM (Operation) used for the purpose of operation maintenance of virtual paths and virtual channels in the ATM (Asynchronous Transfer Mode) VP / VC (Virtual Path / Virtual Channel) exchange system that can process the virtual channel and the virtual path at the same time The present invention relates to an OAM cell discrimination apparatus and method in an ATM VP / VC switching system for cell separation.

In general, the ATM exchange uses the OAM cell in the virtual path stage and the virtual channel stage to maintain and operate the virtual channel of the virtual path.In the case of the exchange of virtual path units, the ATM switch is a segment of the virtual path stage. In case of operating and maintaining virtual path using OAM cell and end-to-end F4 OAM cell and exchanging virtual channel unit, ATM switch is segment F5 OAM cell which is virtual channel level and end-to-end. The virtual path is maintained and operated using the terminal F5 OAM cell.

The F4 OAM cell is classified using the VCI value present in the header of the cell. If the VCI value is 3, the segment F4 OAM cell. If the VCI value is 4, the F4 OAM cell is an end-to-end F4 OAM cell. The F5 OAM cell is classified using the PTI (Payload Type Identifier) value present in the header of the cell. If the PTI value is 4, the segment F5 OAM cell. If the PTI value is 5D, it is an end-to-end F5 OAM cell.

The processing of the OAM cell is performed in a Telecommunication Management Network (TMN), and the ATM exchanger must separate the OAM cell terminated according to the role of the virtual path and the virtual channel and send it to the TMN.

However, the header conversion apparatus and method (application number: 93-27114) capable of processing the virtual path and the virtual channel at the same time in the previously-exchanged ATM exchange (application number: 93-27114) separate the VPI / VCI value of the cell inputted from the subscriber and the VPI For VPI / VCI search means and VPI search means, VCI uses VPI / VCI search means and VPI / VCI separation means for passing to VCI latch, but there is no VCI search means to distinguish F4 OAM cells and to distinguish F5 OAM cells. There is no means for separating and searching for PTI.

Accordingly, as shown in the first embodiment of the ATM VP / VC switch, the end point of the VCC (Virtual Channel Connection) that terminates the inter-station signal cell as the VC switch A in the virtual channel stage is used to process the end-to-end F5 OAM cell and the segment F5 OAM cell. It becomes VC link connection point (VC switch B) to process segment F5 OAM cell in virtual channel stage, or it becomes virtual path connection (VPC) endpoint like VP switch A in virtual path stage, and it is end-to-end F4 OAM cell and segment F4 OAM cell. Or the VP link connection point (VP switch B) to process the segment F4 OAM cell in the virtual path step, so that both the virtual path and the virtual channel according to the configuration example of the VP and VC switch configured as shown in FIG. In the VP / VC exchange, the virtual path of the VP / VC exchange not only distinguishes between the virtual channel and the virtual path but also processes F4 and F5 OAM cells depending on the role of the VP / VC exchange. There is a need for an apparatus and method for distinguishing a role on a (VP link connection point or VPC endpoint) from a role on a virtual channel (VC link connection point or VCC endpoint).

Therefore, the present invention distinguishes the role of the VP / VC switch on the virtual path from the VP link connection point or the VPC endpoint, and the role on the virtual channel from the VC link connection point or the VCC endpoint, and in the case of the VP link connection point, the segment F4 OAM cell. Terminate segment F4 OAM cell and end-to-end F4 OAM cell for VPC end point, terminate segment F5 OAM cell for VC link connection point, and terminate segment F5 OAM cell and end-to-end F5 OAM cell for VCC end point An object of the present invention is to provide an apparatus and method for distinguishing OAM cells in an ATM VP / VC switching system.

The OAM cell discrimination apparatus in the ATM virtual path / virtual channel exchange system of the present invention for achieving the above object is a VP / VC switch for a specific VPI in the OAM cell discrimination apparatus in the ATM virtual path / virtual channel exchange system. VPI retrieving means for outputting a VPCE registration signal to determine whether the terminal terminates the virtual path; VPI / VCI retrieval means for outputting a VCCE registration signal to determine whether the VP / VC switch terminates the virtual channel for a particular VPI / VCI; VCI search means for distinguishing F4 OAM cells; PTI search means for distinguishing F5 OAM cells; Segment that outputs segment F4 OAM termination signal if the VP registration signal is registered in the VPI search means when the segment F4 OAM valid signal is input from the VCI search means, and outputs the segment F4 OAM error signal if it is not registered in the VPI search means. F4 OAM inspection means; When the end-to-end F4 OAM valid signal is input from the VCI search means, if the VPCE registration signal is registered in the VPI search means, the end-to-end F4 OAM termination signal is output and the VPCE registration signal and the VP registration signal are registered in the VPI search means. End-to-end F4 OAM inspection means for outputting an end-to-end F4 OAM error signal if not present; If the VC registration signal is registered in the VPI / VCI search means when the segment F5 OAM valid signal is input from the PTI search means, the segment F5 OAM termination signal is output and the VC registration signal is not registered in the VPI / VCI search means. Segment F5 OAM inspection means for outputting a segment F5 OAM error signal if the registration signal is not registered in the VPI search means; When the end-to-end F5 OAM valid signal is input from the PTI search means, if the VCCE registration signal is registered in the VPI / VCI search means, the end-to-end F4 OAM termination signal is output and the VCCE registration signal and the VC registration signal are the VP search means. An end-to-end F5 OAM checking means for outputting an end-to-end F5 OAM error signal if it is not registered in the VPI and the VP registration signal is not registered in the VPI search means; It characterized in that it further comprises.

In addition, the OAM cell discrimination method in the ATM virtual path / virtual channel switching system applied to the OAM cell discrimination apparatus in the ATM virtual path / virtual channel switching system, when the cell is input, separates the VPI, VCI, and PTI to separate the VPI. The first step is to pass the value to the VPI search means and the VPI / VCI search means, the VCI value to the VCI search means and the VPI / VCI search means, and the PTI to the PTI search means, and the end-to-end F5 OAM is effective at the PTI search means. Outputting the signal, the second step of operating the end-to-end F5 OAM inspection means and header replacement means according to the presence of the VCCE registration number, the VC registration signal, and the VP registration signal; and outputting the segment F5 OAM valid signal from the PTI search means. The third step of operating the segment F5 OAM inspection means, the segment F4 OAM inspection means and the header replacement means according to the presence of the VC registration signal and the VP registration signal, and outputting the end-to-end F4 OAM valid signal from the VCI search means. VPCE registration signal and VP registration signal The fourth step in which the end-to-end F4 OAM inspection means and header replacement means are operated, and if the segment F4 OAM valid signal is output from the VCI retrieval means, the segment F4 OAM inspection means and header are determined according to the existence of the VP registration signal. The fifth step in which the replacement means is operated, and if the valid signals related to the OAM are not generated, the header replacement means is changed according to the existence of the VC registration signal and the VP registration signal searched by the VPI / VCI search means and the VPI search means. And a sixth step of operation.

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

Figure 3 shows the configuration of a header processor for OAM cell classification according to the present invention, adds VCI search means and PTI search means, change the VPI / VCI separation means to VPI / VCI / PTI separation means, VPI / VCCE (VCC End-Point) registration by changing VPI / VCI search means that receives VPI / VCI value from VCI separation means and registers the corresponding VPI / VCI value and outputs the position of header conversion information in VC header conversion table. If the value is to receive VPI value from VPI / VCI separation means and process in VP unit, change VPI search means for outputting the position value with header conversion information of the corresponding virtual path to change VPCE (VPC End-Point). Print the registration status.

That is, the present invention outputs the segment F4 OAM termination signal when the VP registration number is registered in the VPI search means when the segment F4 OAM valid signal is input from the VCI search means for processing the F4 OAM cell and the F5 OAM cell. Segment F4 OAM checker which outputs segment F4 OAM error signal if not registered in VPI search means, and if VPCE registration signal is registered in VPI search means when end-to-end F4 OAM valid signal is input from VCI search means. End-to-end F4 OAM checker that outputs the end F4 OAM end signal and outputs the end-to-end F4 OAM error signal if the VPCE registration signal and the VP registration signal are not registered in the VPI search means, and the segment F5 from the PTI search means. If the VC registration signal is registered in the VPI / VCI search means when the OAM valid signal is input, the segment F5 OAM termination signal is output and the VC registration signal is registered in the VPI / VCI search means. If the VP registration signal is not registered in the VPI search means, the segment F5 OAM checker outputs the segment F5 OAM error signal, and the VCCE registration signal is set to VPI / VCI when the end-to-end F5 OAM valid signal is input from the PTI search means. If it is registered in the search means, the end-to-end F5 OAM end signal is output. If the VCCE registration signal and the VC registration signal are not registered in the VPI / VCI search means, if the VP registration signal is not registered in the VPI search means, An F5 OAM checker is further provided for outputting an F5 OAM error signal.

In the present invention configured as described above, the header replacement means for inputting the header conversion information (VPI0, VCI0, routing information) selected by the header information selection means to the ATM switch is added to the cell separated from the VPI / VCI. OAM end signal (segment F4 OAM end signal, end-to-end F4 OAM end signal, segment F5 OAM end signal, and end-to-end F5 OAM end signal) and OAM error signal (segment F4 OAM end signal, end-to-end F4 OAM The OAM cell is distinguished from the termination signal, the segment F5 OAM termination signal, and the end-to-end F5 OAM termination signal, and transmitted to the TMN. If the OAM termination signal and the OAM error signal are not input, the VC registration signal or the VP registration signal is transmitted. If the cell is transmitted to the ATM switch and the VC registration signal and the VP registration signal are not received, the cell is transmitted to the TMN.

And segment F4 OAM end signal, end-to-end F4 OAM end signal, segment F5 OAM end signal, end-to-end F5 OAM end signal, segment F4 OAM error signal, end-to-end F4 OAM error signal, segment F5 OAM error signal, and End-to-end F5 OAM error signal is output to TMN.

Therefore, when a cell is input, VPI, VCI, and PTI are separated from the VPI / VCI / PTI separating means, and the separated VPI is divided into the VPI / VCI searching means and the VPI searching means, and the VCI is the VPI / VCI searching means, the VCI latch, And forwarded to the VCI search means. In the VPI / VCI search means, all VPI / VCI values to be processed in units of VC and the position information in the VC header conversion table containing the header conversion information of the corresponding channel are entered. Therefore, the VPI / VCI search means indicates that the VPI / VCI value of the cell exists. The VCCE registration signal indicating whether the registration signal and the registered VC become the VCC end point, and the position value with the header conversion information of the corresponding channel are output if the VPI / VCI value of the cell exists.

The output VC registration signal is transmitted to the segment F5 OAM inspector, the end-to-end F5 OAM inspector, the VC header conversion table, the header information selection means, and the header replacement means, and the VCCE registration signal is transmitted to the end-to-end F5 OAM inspector. The position value having the output header conversion information is transmitted to the VC header conversion table together with the VC registration signal. The VC header conversion table then outputs the header conversion information of the corresponding channel and delivers it to the header information selection means. The VPI search means has all VPI values to be processed in VP units and corresponding position values of header conversion information. If the VPI of an input cell is to be processed in VP units, the VP indicates that a VPI value exists in the VPI search means. The registration signal, the VPCE registration signal indicating whether the registered VP becomes the VPC end point, and the position value of the header conversion information corresponding to the corresponding VPI are output. The output VP registration signal is sent to segment F5 OAM inspector, end-to-end F5 OAM inspector, segment F4 OAM inspector, end-to-end F4 OAM inspector, VP header conversion table, and header replacement means. Passed to checker. When the position value of the header transformation information is input together with the VP registration signal, the VP header transformation table transfers the header transformation information of the position to the header information selecting means.

The header information selecting means selects header conversion information to be delivered to the header replacing means based on the VC registration signal inputted from the VPI / VCI searching means. That is, if the VPI / VCI value of the cell is registered in the VPI / VCI retrieval means, it indicates that the cell should be processed in VC units. Therefore, regardless of the VP retrieval means, the header information selection means outputs the output of the VC header conversion table (VPI0, VCI0, and mounting. Information) to the head replacement unit, and if the cell's VPI / VCI value is not registered in the VPI / VCI search unit and the cell's VPI value is registered only in the VPI search unit, the output of the VP header conversion table (VPI0, routing information) is transmitted. ) And the VCI value stored in the VCI latch are passed to the header replacement means. In other words, when processing in VP units, the header processing unit passes the VCI value unchanged.

In a VP / VC switch, the processing of OAM cells depends on the role of the virtual path and the virtual channel. To distinguish the role of the virtual path of the VP / VC switch, if the VP / VC switch belongs to the VP link connection point, the VP registration signal is registered to the VPI search means. If it belongs to the VPC endpoint, the VPCE registration signal is registered with the VP registration signal. If the VP-VC switch belongs to the VC link connection point, the VC registration signal is registered in the VPI / VCI search means. If the VP-VC switch belongs to the VCC end point, the VC registration signal is registered and the VCCE registration signal is registered. do.

When the end-to-end F5 OAM cell is input, if the VP / VC switch corresponds to the VCC end point by the VCCE registration signal, the cell is terminated. If the VP / VC switch corresponds to the VC link connection point by the VC registration signal, the cell is converted. After the switch, when the VP / VC switch is located in the virtual path by the VP registration signal, the cell is transferred to the switch after header conversion. When the segment F5 OAM cell is input, the cell is terminated by the VC registration signal. When the VP / VC switch is located on the virtual path by the VP registration signal, the cell is transferred to the switch after header conversion.

When the end-to-end F4 OAM cell is input, if the VP / VC switch corresponds to the VPC endpoint by the VPCE registration signal, the cell is terminated. If the VP / VC switch corresponds to the VP link connection point by the VP registration signal, the cell is converted. To be transferred to the switch. When the segment F4 OAM cell is input, if the VP / VC switch is located before the VPC endpoint or VP link connection by the VP registration signal, the cell is terminated.

In the PTI search means, if the PTI value of the cell is 4, the segment F5 OAM valid signal is transmitted to the segment F5 OAM inspector. The segment F5 OAM inspector sends the segment F5 OAM termination signal when the VC registration signal is registered in the VPI / VCI search means. If the VC registration signal is not registered in the VPI / VCI retrieval means and the VP registration signal is not registered in the VPI retrieval means in the replacement means and the TMN, the segment F5 OAM error signal is output to the header replacement means and the TMN.

In the PTI search means, if the cell has a PTI value of 5, the end-to-end F5 OAM valid signal is transmitted to the end-to-end F5 OAM checker. The end-to-end F5 OAM checker terminates if the VCCE registration signal is registered in the VPI / VCI search means. When the large F5 OAM termination signal is not registered in the header replacement means and TMN, the VCCE registration signal is not registered in the VPI / VCI retrieval means, and the VC registration signal is not registered in the VPI / VCI retrieval means, the VP registration signal is retrieved by the VPI. If not registered in the means, the end-to-end F5 OAM error signal is output to the header replacement means and the TMN.

In the VCI search unit, if the cell has a VCI value of 3, the segment F4 OAM valid signal is transmitted to the segment F4 OAM inspector. The segment F4 OAM inspector transmits the segment F4 OAM termination signal to the header replacement unit if the VP registration signal is registered in the VPI search unit. And the segment F4 OAM error signal is outputted to the header replacing means and the TMN, if not registered in the VPI search means.

In the VCI search means, if the cell's VCI value is 4, the end-to-end F4 OAM valid signal is transmitted to the end-to-end F4 OAM checker.The end-to-end F4 OAM checker sends an end-to-end F4 signal if the VPCE registration signal is registered to the VPI search means. If the OAM termination signal is not registered in the header replacement unit and TMN, and the VPCE registration signal is not registered in the VPI search unit and the VP registration signal is not registered in the VPI search unit, the end-to-end F4 OAM error signal is output to the header replacement unit and TMN. do.

The header replacing means transmits the cell to the TMN if neither the signals input from the VPI / VCI searching means nor the VPI searching means (VC registration signal, VP registration signal) are registered, and if registered, the header information selecting means. The selected header conversion information (VPI0, VCI0, routing information) is added to the cell where VPI / VCI is separated, and then segment F4 OAM termination signal, end-to-end F4 OAM termination signal, segment F5 OAM termination signal, end-to-end F5 OAM termination If a signal, segment F4 OAM error signal, end-to-end F4 OAM error signal, segment F5 OAM error signal, and end-to-end F5 OAM error signal are delivered, the cell is transmitted to the TMN, otherwise it is sent to the ATM switch. .

4 is an exemplary configuration diagram of the PTI search means, wherein the PTI search means uses a VPI / VCI signal as a comparison enable signal and a constant for comparing the PTI value with the constant 4 and a comparator with a constant 5 for comparing the input PTI value with the constant 5. It consists of a comparator with four.

The comparator with constant 5 compares the input PTI value with the constant 5 and the match signal is the end-to-end F5 OAM valid signal. The comparator with constant 4 compares the PTI value with the constant 4 and matches the match signal with the segment signal F5 OAM. Used as a valid signal.

5 is an exemplary configuration diagram of the VCI search means, wherein the VCI search means uses a VPI / VCI signal as a comparison enable signal, and a constant for comparing the input VCI value with the constant 4 and a constant 3 for comparing the PTI value with the constant 3. It consists of a comparator with three. The comparator with constant 4 compares the input VCI value with the constant 4 if the match signal is an end-to-end F4 OAM valid signal. The comparator with constant 3 compares the VCI value with the constant 3 and matches the match signal with the segment F4 OAM. Used as a valid signal.

6 is an exemplary configuration diagram of the existing VPI / VCI search means, using CAM as the VPI / VCI search means, using the input VPI / VCI as the key value to be compared with the values in the CAM, and using the VPI / VCI valid signal as the comparison of the CAM. The signal is used as an enable signal and a match signal indicating whether a key value is in the CAM is used as the VC registration signal and the associated data is used as the VC header position information.

FIG. 7 is an exemplary configuration diagram of the VPI / VCI retrieval means of the present invention. Unlike FIG. 6, the associated data is used as the VC header position information and the VCCE registration signal. Using the VCCE registration signal, the VP / VC exchange verifies the VCC endpoint against the VPI / VCI value.

8 is an exemplary configuration diagram of a conventional VPI search means, which includes a latch for storing a VPI by a VPI / VCI valid signal and a position value with a header conversion information of the corresponding VP and a VP registration signal using the VPI stored in the latch as an address value. It consists of a memory that outputs.

FIG. 9 is an exemplary configuration diagram of the VPI searching means of the present invention. Unlike FIG. 8, a data bit indicating a VPCE registration signal is placed in a memory to check whether a VPI value belongs to a VP end point in a virtual path step.

FIG. 10 is an exemplary configuration diagram of an end-to-end F5 OAM checker according to the present invention, which logically combines an end-to-end F5 OAM valid signal and a VCCE registration signal for operation maintenance of a virtual channel (VCC) corresponding to a VPI / VCI value. Multiply true to output the end-to-end F5 OAM termination signal and logically multiply the end-to-end F5 valid signal, the inverted signal of the VCCE registration signal, the inverted signal of the VC registration signal, and the inverted signal of the VP registration signal to true. F5 Output OAM error signal.

11 is an exemplary configuration diagram of the segment F5 OAM checker according to the present invention. The segment F5 OAM valid signal and the VC registration signal are logically multiplied to maintain the operation of virtual channels (VCC and VC link) corresponding to the VPI / VCI value. If true, the segment F5 OAM termination signal is output, and if the segment F5 valid signal, the inversion signal of the VC registration signal, and the inversion signal of the VP registration signal are logically multiplied, the segment F5 OAM error signal is output.

FIG. 12 is an exemplary configuration diagram of an end-to-end F4 OAM checker according to the present invention, and a VPCE registration indicating an end-to-end F4 OAM valid signal and an end point of a VPC for operation maintenance of a virtual path (VPC) corresponding to a VPI value. Logically multiply the signal to true to output the end-to-end F4 OAM termination signal, and logically multiply the end-to-end F4 valid signal, the inverted signal of the VPCE registration signal, and the inverted signal of the VP registration signal to true to end-to-end F4 OAM error. Output the signal.

13 is an exemplary configuration diagram of the segment F4 OAM checker according to the present invention. If the segment F4 OAM valid signal and the VP registration signal are logically true for the operation maintenance of the virtual path (VPC and VP link) corresponding to the VPI value, FIG. Outputs the segment F4 OAM termination signal and logically multiplies the segment F4 valid signal by the inverted signal of the VP registration signal to output the segment F4 OAM error signal.

FIG. 14 is a flow chart for processing OAM cell discrimination according to the present invention. When a cell is input, the VPI, VCI, and PTI are separated from the cell, and the VPI value is assigned to the VPI search means, the VPI / VCI search means, and the VCI value is the VCI search means. To the VPI / VCI retrieval means, the PTI is passed to the PTI retrieval means.

When the end-to-end F5 OAM valid signal is output from the PTI search means, when the VCCE registration signal is present in the VPI / VCI search means, the end-to-end F5 OAM checker sends the end-to-end F5 OAM end signal, and the header replacement means the cell TMN. To be delivered. If the VCCE registration signal does not exist in the VPI / VCI retrieval means and the VC registration signal exists in the VPI / VCI retrieval means, the header replacement means reads the header conversion information from the VC header conversion table and transfers the cell to the switch after the header conversion of the cell. If the VCCE registration signal and the VC registration signal are not present in the VPI / VCI retrieval means and the VP registration signal is present in the VPI retrieval means, the header replacement means reads the header conversion information from the VP header conversion table, and then converts the cell to the switch. If the VCCE registration signal, the VC registration signal, and the VP registration signal do not exist, the end-to-end F5 OAM checker transmits the end-to-end F5 OAM error signal, and the header replacement means transmits the cell to the TMN.

When the PTI retrieval unit outputs the segment F5 OAM valid signal, when the VC registration signal exists in the VPI / VCI retrieval unit, the segment F5 OAM checker transmits the segment F5 OAM termination signal, and the header replacement unit transmits the cell to the TMN. If the VC registration signal does not exist in the VPI / VCI retrieval means and the VP registration signal exists in the VPI retrieval means, the header replacement means reads the header conversion information from the VP header conversion table and transfers the cell to the switch after the header conversion of the cell. If the registration signal and the VP registration signal are not present in the VPI / VCI retrieval means and the VPI retrieval means, respectively, the segment F4 OAM checker transmits the segment F4 OAM error signal, and the header replacement means transmits the cell to the TMN.

When the VCI search means outputs the end-to-end F4 OAM valid signal, if the VPCE registration signal is present in the VPI search means, the end-to-end F4 OAM checker sends the end-to-end F4 OAM end signal and the header replacement means transmits the cell to the TMN. Do it. If the VPCE registration signal does not exist in the VPI search means and the VP registration signal exists in the VPI search means, the header replacement means reads the header conversion information from the VP header conversion table and transfers the cell to the switch after the header conversion of the cell. The large-end F4 OAM checker sends an end-to-end F4 OAM error signal to the TMN by the header replacement means.

When the VCI retrieval unit outputs the segment F4 OAM valid signal, when the VP registration signal exists in the VPI retrieval unit, the segment F4 OAM checker transmits the segment F4 OAM termination signal and the header replacement unit transmits the cell to the TMN. If the VP registration signal does not exist in the VPI retrieval means, the segment F4 OAM checker transmits the segment F4 OAM error signal to the TMN in the header replacement means.

If the OAM-related valid signals (end-to-end F5 OAM valid signal, segment F5 OAM valid signal, end-to-end F4 OAM valid signal, and segment F5 OAM valid signal) are not generated, the VC registration signal is searched for VPI / VCI. Means for retrieving the VP registration signal from the VPI search means and if the VC registration signal is present in the VPI / VCI search means, the header replacement means reads the header conversion information from the VC header conversion table and delivers the cell to the switch after header conversion of the cell. If the VC registration signal does not exist in the VPI / VCI retrieval means and the VP registration signal exists in the VPI retrieval means, the header replacement means reads the header conversion information from the VP header conversion table and transfers the cell to the switch after the header conversion of the cell. If neither signal is present, the cell is forwarded to the TMN.

As described above, according to the present invention, the role of the VP / VC switch on the virtual path for the processing of the F4 and F5 OAM cells that differs depending on the role of the VP / VC switch as well as the distinction between the virtual channel and the virtual path that is the switching unit (VP) There is an effect of distinguishing the link connection point or the VPC endpoint and the role on the virtual channel (VC link connection point or the VCC endpoint).

Claims (9)

An OAM cell discrimination apparatus in an ATM virtual path / virtual channel switching system, comprising: VPI retrieving means for outputting a VPCE registration signal to determine whether a VP / VC switch terminates a virtual path for a specific VPI; VPI / VCI retrieval means for outputting a VCCE registration signal to determine whether the VP / VC switch terminates the virtual channel for a particular VPI / VCI; VCI search means for distinguishing F4 OAM cells; PTI search means for distinguishing F5 OAM cells; When the segment F4 OAM valid signal is input from the VCI search means, the segment F4 OAM termination signal is output if the VP registration signal is registered in the VPI search means, or the segment F4 OAM error signal is output if it is not registered in the VPI search means. Segment F4 OAM inspection means; When the end-to-end F4 OAM valid signal is input from the VCI search means, if the VPCE registration signal is registered in the VPI search means, the end-to-end F4 OAM termination signal is output and the VPCE registration signal and the VP registration signal are registered in the VPI search means. End-to-end F4 OAM checking means for outputting an end-to-end F4 OAM error signal if not present; If the VC registration signal is registered in the VPI / VCI search means when the segment F5 OAM valid signal is input from the PTI search means, the segment F5 OAM termination signal is output and the VC registration signal is not registered in the VPI / VCI search means. Segment F5 OAM inspection means for outputting a segment F5 OAM error signal if the registration signal is not registered in the VPI search means; When the end-to-end F5 OAM valid signal is input from the PTI search means, if the VCCE registration signal is registered in the VPI / VCI search means, the end-to-end F5 OAM termination signal is output and the VCCE registration signal and the VC registration signal are VPI / VCI. ATM virtual path / virtual further comprising an end-to-end F5 OAM checking means for outputting an end-to-end F5 OAM error signal if it is not registered in the search means and the VP registration signal is not registered in the VPI search means. OAM cell discriminating device in a channel switching system. The method according to claim 1, wherein if all of the signals (VC registration signal, VP registration signal) input from the VPI / VCI search means and the VPI search means are not registered, the cell is transmitted to the TMN. Add the header conversion information (VPI0, VCI0, routing information) selected by the means to the cell in which the VPI / VCI is separated, and then end-to-end F5 OAM inspection means, segment F5 OAM inspection means, end-to-end F4 OAM inspection means, and Segment F4 OAM end signal, end-to-end F4 OAM end signal, segment F5 OAM end signal, end-to-end F5 OAM end signal, segment F4 OAM error signal, end-to-end F4 OAM error signal, segment When the F5 OAM error signal, and the end-to-end F5 OAM error signal is transmitted, the cell is transmitted to the TMN, otherwise the ATM virtual further comprising a header replacement means for transmitting to the ATM switch. OAM cells distinguishing device according to the in / virtual channel switching system. In the OAM cell discrimination method applied to the OAM cell discrimination apparatus in the ATM virtual path / virtual channel switching system, when a cell is input, the VPI, VCI, and PTI are separated and the VPI value is applied to the VPI searching means and the VPI / VCI searching means. The VCI value is transmitted to the VCI search means and the VPI / VCI search means, and the PTI is transmitted to the PTI search means. When the PTI search means outputs an end-to-end F5 OAM valid signal, the VCCE registration signal, the VC registration signal, A second step in which the end-to-end F5 OAM inspection means and the header replacement means operate according to the presence of the VP registration signal, and if the segment F5 OAM valid signal is output from the PTI search means, the presence of the VC registration signal and the VP registration signal is present. According to the third step of operating the segment F5 OAM inspection means, the segment F4 OAM inspection means and the header replacement means, and outputting the end-to-end F4 OAM valid signal from the VCI retrieval means, the existence of the VPCE registration signal and the VP registration signal is determined. End-to-end F4 OAM inspection However, the fourth step of operating the header replacement means, the fifth step of operating the segment F4 OAM checking means and the header replacement means according to the presence of the VP registration signal when the VCI search means outputs the segment F4 OAM valid signal; And if the valid signals related to the OAM are not generated, a sixth step of operating the header replacement means according to the existence of the VC registration signal and the VP registration signal searched by the VPI / VCI search means and the VPI search means. A method for distinguishing OAM cells in ATM virtual path / virtual channel switching system. 4. The method of claim 3, wherein in the second step, when the VCCE registration signal is present in the VPI / VCI retrieval means, the end-to-end F5 OAM termination means sends the end-to-end F5 OAM termination signal and the header replacement means returns the cell to the TMN. If the VCCE registration signal does not exist in the VPI / VCI retrieval means and the VC registration signal exists in the VPI / VCI retrieval means, the header replacement means reads the header conversion information from the VC header conversion table and transfers the header of the cell. After the eighth step of delivering the cell to the switch, and if the VCCE registration signal and the VC registration signal do not exist in the VPI / VCI retrieval means and the VP registration signal exists in the VPI retrieval means, the header replacement means converts the header in the VP header conversion table. In the ninth step of reading the information and delivering the cell to the switch after the header conversion of the cell, and if neither the VCCE registration signal, the VC registration signal nor the VP registration signal exists, the end-to-end F5 OAM inspection means detects the end-to-end F5 OAM error signal. , Header value It means the method of distinguishing OAM cell from the ATM virtual path / virtual channel switching system comprising: a tenth step of passing the cell in the TMN. 4. The method of claim 3, wherein the third step comprises: when the VC registration signal is present in the VPI / VCI retrieval means, the segment F5 OAM inspection means delivers the segment F5 OAM termination signal, and the header replacement means delivers the cell to the TMN. Step 7 and if the VC registration signal does not exist in the VPI / VCI retrieval means and the VP registration signal exists in the VPI retrieval means, the header replacement means reads the header conversion information from the VP header conversion table, and then converts the cell into the switch. If the eighth step and the VC registration signal and the VP registration signal are not present in the VPI / VCI retrieval means and the VPI retrieval means, respectively, the segment F4 OAM inspection means sends a segment F4 OAM error signal, and the header replacement means returns the cell to the TMN. And a ninth step of transmitting the OAM cell in the ATM virtual path / virtual channel switching system. 4. The method of claim 3, wherein the fourth step is such that, when the VPCE registration signal is present in the VPI retrieval means, the end-to-end F4 OAM termination means delivers the end-to-end F4 OAM termination signal and the header replacement means transfers the cell to the TMN. Step 7, and if the VPCE registration signal is not present in the VPI retrieval means and the VP registration signal is present in the VPI retrieval means, the header replacement means reads the header conversion information from the VP header conversion table, and then converts the cell to the switch. An eighth step of transmitting, and an end-to-end F4 OAM error means, if neither the VPCE registration signal nor the VP registration signal exists, a ninth step of delivering the cell to the TMN in the header replacement means; Method for distinguishing OAM cells in ATM virtual path / virtual channel switching system, characterized in that. 4. The method of claim 3, wherein the fifth step comprises: a seventh step of transmitting a segment F4 OAM termination signal by the segment F4 OAM inspection means and a cell by the header replacement means when the VP registration signal exists in the VPI search means; If the VP registration signal is not present in the VPI retrieval means, the segment F4 OAM inspection means includes an eighth step of delivering the segment F4 OAM error signal and the header replacement means to transmit the cell to the TMN. Method of distinguishing OAM cell in channel communication system. 4. The method of claim 3, wherein the sixth step comprises: when the VC registration signal is present in the VPI / VCI retrieval means, the header replacement means reads the header conversion information from the VC header conversion table and delivers the cell to the switch after the header conversion of the cell; Step 7 and if the VC registration signal does not exist in the VPI / VCI retrieval means and the VP registration signal exists in the VPI retrieval means, the header replacement means reads the header conversion information from the VP header conversion table, and then converts the cell into the switch. A method of distinguishing OAM cells in an ATM virtual path / virtual channel switching system, comprising: transmitting, but transmitting the cell to a TMN if neither signal exists. 4. The VP registration signal and the VPCE of the VPI retrieval means according to claim 3, wherein the VP / VC switch acts as a VP link connection point or a VPCE for a specific VPI in order to determine the virtual path and the role on the virtual channel of the VP / VC switch. As a registration signal, the data of the VPI retrieval means composed of RAM to determine whether the VP / VC switch acts as a VC link connection point or a VCCE for a particular VPI / VCI by the VC registration signal and the VCCE registration signal of the VPI / VCI retrieval means. In an ATM virtual path / virtual channel switching system, a bit is allocated for a VPCE registration signal in a bus or an associated data bit is assigned as a VCCE registration signal in a VPI / VCI retrieval means composed of CAMs. How to distinguish OAM cells.