KR19990035434A - Loopback Test Method of Control Board in ATM LAN System - Google Patents

Abstract

The present invention relates to a loopback test method for testing the cutting and recombination (SAR) function of the control board constituting the ATM-LAN system.

The present invention includes at least one control board, and consists of a plurality of user network matching boards and switch boards controlled by the control boards to connect / exchange a plurality of low speed ATM users, high speed ATM users, and Ethernet users. An ATM LAN system capable of configuring a LAN in an ATM system, the method comprising: initializing the control board; Generating a test cell for testing; Setting routing information of the cell bus matching unit to configure a loopback path for receiving the cell sent from the cell; And transmitting and receiving a test cell and comparing whether the received cell matches the transmitted cell.

Therefore, according to the present invention, since the SAR transmission and reception system can be tested very simply, there is an effect of facilitating maintenance in the ATM-LAN system to which the present invention is applied.

Description

Loopback testing method of control module in ATM-LAN system

The present invention relates to an ATM-LAN system, and more particularly, to a loopback test method for testing a cut and recombination (SAR) function of a control board constituting an ATM-LAN system.

In general, the asynchronous transfer mode (ATM) communication method is to transmit information using a fixed length (53 bytes) information block called a cell using the ATDM method. This ATM communication system forms a hierarchical structure as shown in Table 1 below and has standardized standards for each layer.

hierarchy Sublayer function Upper hierarchy - Higher layer function ATM Adaptation Layer Convergence (CS) sublayer Convergence function Cutting and recombination Cutting function and recombination function ATM layer - General Flow Control and Cell Header Processing Physical layer Transmission Convergence (TC) HEC signal generation and extraction function Physical medium Bit time information function

As shown in Table 1, the ATM communication method is divided into vertical structures such as a physical layer, an ATM layer, an ATM adaptation layer (AAL), and a higher protocol layer. The Segmentation And Reassembly sublayer (CS) and Convergence Sublayer (CS) sublayers are subdivided. The physical layers are subdivided into physical media (PM) and transmission convergence (TC) sublayers.

On the other hand, in implementing a high-speed LAN system, it is a trend to gradually use the AMT method, but the existing LAN system, such as Ethernet is still more widely used is required a LAN system that can accommodate them. The ATM system to which the present invention is applied is designed not only to accommodate existing Ethernet users, but also to connect both high speed ATM users and low speed ATM users.

However, in constructing such an ATM-LAN system, a control module that manages the functions of the entire boards is connected to the cell bus in an ATM manner to exchange cells. There is a problem that is difficult to maintain due to the lack of function.

Accordingly, an object of the present invention is to provide a method for testing a SAR block performing an ATM communication function with its own loopback in a control board implementing an ATM-LAN system.

In order to achieve the above object, the method of the present invention includes at least one control board, and consists of a plurality of user network matching boards and switch boards controlled by the control board, and a plurality of low speed ATM users and high speed. An ATM LAN system configured to connect / exchange an ATM user and an Ethernet user to configure an LAN in an ATM method, comprising: initializing the control board; Generating a test cell for testing; Setting routing information of the cell bus matching unit to configure a loopback path for receiving the cell sent from the cell; And transmitting and receiving a test cell and comparing whether the received cell matches the transmitted cell.

1 is a connection diagram of an ATM system to which the present invention is applied;

2 is a schematic structural diagram of boards constituting an AMT LAN system;

3 is a detailed configuration diagram of the SAR unit of the control board,

4 is a flowchart illustrating a loopback test method according to the present invention.

* Explanation of symbols for main parts of the drawings

100: local system 110, 120, 130: personal computer

140: AT LAN system 140 150: another LAN system

310: SAR transmitter 320: local memory

330: packet memory 340: control memory

350: conversion RAM 360: cell bus matching unit

370: SAR receiver

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

The ATM-LAN system to which the present invention is applied includes a personal computer 110 mounted with an ATM network matching card (ATM NIC) for providing a low-speed ATM connection, as shown in FIG. A personal computer 120 mounted with an ATM network matching card (ATM NIC) for providing an ATM connection and a computer 130 mounted with an Ethernet card for providing an Ethernet connection are connected to the ATM LAN system 140. The ATM LAN system 140 is configured to be connected to another ATM local area network 150 at a speed of 155M. That is, the ATM LAN system 140 to which the present invention is applied is configured to connect a low speed ATM user, a high speed ATM user, and an Ethernet user.

As shown in FIG. 2, the ATM-LAN system includes a control board 141 and a switch board 142, a user network matching (UNI) board 143 for providing a high speed ATM connection, A user network matching (UNI) board 144 for providing a low speed ATM connection, and a user network matching (UNI) board 145 for providing an Ethernet connection.

These user network matching boards are connected to and exchanged with the switch board and the ATM method, and the control board is connected with the cell bus and the ATM method to exchange IPC cells. For example, although not shown in the drawing, the Ethernet user network registration board is connected to the CPU module, the bridge module for connecting the host bus and the PCI bus, the SAR part which is connected to the PCI bus, and provides a switching function with the PCI bus. It consists of a switching Ethernet control unit for connecting an Ethernet subscriber. That is, the Ethernet user network matching unit matches a plurality of users such as a personal computer on which an Ethernet card is mounted, processes the data by a high-speed ATM method, and connects the switch board to the switchboard. As such, all user network matching boards are connected to the switch in a fast ATM manner so that AMT cells are exchanged.

On the other hand, the control board also has a SAR block 300 as shown in Figure 3 to process the IPC cells in the ATM (ATM) method, this SAR block 300 is a SAR transmitter (SARA-S: 310, a local memory (320), a packet memory 330, a control memory 340, a conversion RAM (TRAM: 350), a cell bus matching unit (CUBIT: 360), a SAR receiving unit (SARA-R: 370).

SNMP and signaling, which are network software processed in ATM LAN systems, process messages using the AAL layer, and send these messages to ATM cells through the ATM layer to send them to their destinations. At this time, a segmentation function for dividing the messages into ATM cells is required at the transmitting side, and a reassembly function for reassembling the received ATM cells is required at the receiving side. SARA-Rs are used.

The present invention is to test the SAR function of the SAR block is configured as described above, the flow of the method is to initialize the control board (Control Module) as shown in Figure 4 (S1), generating a test cell (S2), the step of setting the CUBIT routing information (S3), the test cell transmission and reception step (S4), the transmission and reception information comparison check step (S5), the step of determining whether to match or display the error or normal (S6, S7, S8 ), And the step (S9) of checking whether or not to continue.

Referring to FIG. 4, in step S1, components of the control board are initialized. In step S2, in order to test the SAR chips 310 and 370, a test cell is generated at the SAR transmitting side, stored in the local memory 320, and VPI and VCI are set.

In step S3, the routing information of the cell bus matching unit 360 is set to set the loopback path so that the cell to be transmitted is received by the cell bus again. That is, when transmitting the test cells accumulated in the packet memory 330 of the SAR transmission, the cell bus matching unit 360 exits to the cell bus and then the cell bus matching unit CUBIT: 360 of the control board 141. ), Routing header information, VPI, and VCI information are set in the conversion RAM (TRAM) 350. This information is made using the VPI, VCI, and CUBIT ID of the control board to be tested.

Subsequently, in step S4, the test cell generated in step S2 is disappeared and transmitted through the transmitter 310, and then received and stored in the local memory 320 again. That is, in the test cell transmission and reception step, information stored in the local memory is copied as much as the size to be tested by the packet memory 330 of the SAR transmission. After that, arbitrary VPI and VCI can be designated for the test, and a predetermined size is cut from a predetermined address area and loaded on the payload area. Then, the test cells stacked in the predetermined buffer area of the packet memory are transmitted to the cell bus matching unit 360 through the operation of the SAR transmitting unit 310, and received again from the cell bus to receive the SAR of the packet memory 330. Stack on the area. This information is then copied to a specific area of the pre-allocated local memory 320.

In step S5 & S6 it is compared whether the transmitting cell and the receiving cell stored in the local memory match. As a result of the comparison, it can be confirmed that the SARA transmission and reception system is normal, and if it does not match, it can be seen that a failure occurs in the path. That is, it checks whether there is an abnormality by comparing the contents of the predetermined size among the information prepared in advance for transmission and reception to the cell bus through SAR transmission and the contents of the information received by SAR reception and accumulated in the reception area.

Therefore, according to the comparison result, an error state is displayed in step S8, and a normal state is displayed in step S7. Subsequently, in step S9, if it is determined whether to continue the test and continues, the process returns to step S4 and continues to transmit and receive the test cell.

As described above, since the SAR transmission and reception system can be tested very simply according to the present invention, there is an effect of facilitating maintenance in an ATM-LAN system to which the present invention is applied.

Claims (1)

It includes at least one control board, and consists of a plurality of user network matching board and switch board controlled by the control board to connect / exchange a number of low-speed ATM users, high-speed ATM users and Ethernet users In the ATM LAN system, which can be configured as a LAN, Initializing the control board; Generating a test cell for testing; Setting routing information of the cell bus matching unit to configure a loopback path for receiving the cell sent from the cell; And And transmitting and receiving a test cell and comparing whether the received cell is identical with the transmitted cell.