JPH08265325A - Atm connection test device - Google Patents

Abstract

PURPOSE: To obtain an ATM connection test device capable of easily specifying a fault side of an ATM connection and easily confirming a test result. CONSTITUTION: Plural devices provided with parts (A)-(B) are provided in the midst of the ATM connection that is the communication path of an ATM cell, (A) an ATM cell input part 10 to which the ATM cell is inputted, (B) an ATM cell counter part 20 which counts valid ATM cell out of the ATM cells inputted to the ATM cell input part 10, and (C) a display part 30 which displays a value counted by the ATM cell counter part 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ATM connection testing device, and more particularly to a device provided in the middle of an ATM connection for testing continuity and quality of the ATM connection.

[0002]

2. Description of the Related Art In an ATM switch, all information is transferred to an ATM regardless of the type of communication media such as voice, image and data.
It is transferred in fixed length blocks called cells. A
As shown in FIG. 2, the TM cell is composed of a header part and an information field part (payload part), and the header part has an identifier VPI (Virtual Path Ident) indicating a destination.
ifier; virtual path identifier) and VCI (Virtual Channe)
l Identifier; virtual channel identifier) is stored. Then, the ATM cell is transferred to the destination based on these VPI and VCI.

By the way, conventionally, in A
The following two methods are used to test the continuity or quality of the TM connection. The first test method is a method in which a test cell is flowed from a test device to a test route for testing.

The second test method is OAM (Operation An
d Maintenance) Cell continuity check,
This is a method of using an OAM function such as performance monitoring loopback.

[0005]

In the first test method, it may be necessary to perform the test a plurality of times to identify the location of the failure. For example, the test route 8 shown in FIG. 8, that is, the first INF 1A to the first common unit 2A, ATM
Switch 4, third common portion 2C, LOOP package 1
C, third common unit 2C, ATM switch 4, second common unit 2
To test the route through B to the second INF1B,
As shown in FIG. 9, the second INF 1B to the first INF 1A
Test device 5 during the route (ATM connection) to
Is provided.

When it is determined that the ATM connection 8 has a failure, in order to know where in the route there is a failure, the ATM connection 8A shown in FIG.
It is necessary to test two test routes of the ATM connection 8B shown in FIG. That is, the ATM connection 8 of FIG. 9 is from the first INF 1A to the LOOP package 1
It is considered that it is composed of the first ATM connection 8A reaching C and the second ATM connection 8B reaching the second INF 1B from the LOOP package 1C.
The first ATM connection 8A shown in FIG. 11 is tested, and the second ATM connection 8B shown in FIG. 11 is also tested.

[0007] The INF is an INterFace unit designed for each service, and is individually ATM.
It is one of the individual units that perform cell processing. Further, the LOOP package is a package having a function of looping an ATM cell and is one of individual units like the INF.

Next, the second test method has a problem that the failure cannot be isolated unless each relay point or each device has a function of inserting / separating or checking the OAM cell. . The hardware for using such an OAM cell processing function is considerably large-scaled, and each device has such a function, which causes a problem of cost increase.

The present invention has been made in view of the above circumstances, and it is possible to use the AAM without using the OAM cell processing function.
It is an object of the present invention to provide an ATM connection test device which can easily identify a failure location of a TM connection and can easily confirm a test result.

[0010]

[Means for Solving the Problems]

<< First Configuration of ATM Connection Testing Device According to the Present Invention >> The ATM connection testing device according to the present invention is
In order to solve the above-mentioned problems, a plurality of ATM cells are provided in the middle of an ATM connection which is a communication path of the ATM cell.
This is a device for testing the continuity and quality of a TM connection, and comprises an ATM cell input unit 10, an ATM cell counting unit 20, and a display unit 30 as essential components (corresponding to claim 1). Hereinafter, this configuration will be referred to as a first configuration of the ATM connection test apparatus. FIG. 1 is a principle diagram of the present invention.

(ATM Cell Input Unit 10) The ATM cell input unit 10 inputs the ATM cell. (ATM cell counting unit 20) The ATM cell counting unit 20 counts valid ATM cells among the ATM cells input to the ATM cell input unit 10.

(Display unit 30) The display unit 30 is the ATM
The value counted by the cell counter 20 is displayed. As the display unit 30, for example, a CRT display, LCD display, plasma display or the like can be used. The display method is preferably decimal display, but may be hexadecimal display or binary display, for example.

Next, the structure of the ATM connection test apparatus may be configured as shown in (a) to (e) below. << Second Configuration of ATM Connection Testing Device in the Present Invention >> (a) A count value clearing unit 40 for clearing the count value counted by the ATM cell counting unit 20 is provided (corresponding to claim 2). Hereinafter, this configuration will be referred to as a second configuration of the ATM connection test apparatus.

<< Third Configuration of ATM Connection Testing Device According to the Present Invention >> (b) In the ATM cell counter 20, the data stored in the header or the payload among the valid cells has a predetermined value. Counting only ATM cells (corresponding to claim 3). Hereinafter, this configuration will be referred to as a third configuration of the ATM connection test apparatus.

<< Fourth Configuration of ATM Connection Testing Device According to the Present Invention >> (C) A specific cell detection unit 50 for detecting a specific cell from the ATM cells input to the ATM cell input unit 10 is provided. When the detection unit 50 detects a specific cell, the display unit 30 displays that the specific cell has passed (corresponding to claim 4). Hereinafter, this configuration will be referred to as a fourth configuration of the ATM connection test apparatus.

<Fifth Configuration of ATM Connection Testing Apparatus According to the Present Invention> (D) A specific cell detection unit 50 for detecting a specific cell from the ATM cells input to the ATM cell input unit 10 is provided, and this specific cell is provided. The ATM cell counting unit 20 starts or stops counting of the ATM cells when the detection unit 50 detects a specific cell (corresponding to claim 5). Hereinafter, this configuration will be referred to as a fifth configuration of the ATM connection test apparatus.

<< Sixth Configuration of ATM Connection Testing Apparatus According to the Present Invention >> (e) A specific cell detecting section 50 for detecting a specific cell from the ATM cells input to the ATM cell input section 10 is provided, and this specific cell is provided. The count value clearing unit 40 stops the display of the display unit 30 when the detection unit 50 detects a specific cell (corresponding to claim 6). Hereinafter, this configuration will be referred to as a sixth configuration of the ATM connection test apparatus.

Here, to stop the display means to hold the displayed contents. In this case, the ATM cell counting section 20 may stop the counting operation,
You may continue.

<< Seventh Configuration of ATM Connection Testing Apparatus According to the Present Invention >> The ATM connection testing apparatus according to the present invention is configured to include an ATM cell input section 10, an ATM cell counting section 20, and a display section 30 as essential components. (Corresponding to claim 7). This configuration will be referred to as AT
This is called the seventh configuration of the M connection test apparatus.

(ATM Cell Input Unit 10) A plurality of ATM cell input units 10 are provided in the middle of an ATM connection which is a communication path of an ATM cell and inputs the ATM cell.

(ATM Cell Counting Unit 20) The ATM cell counting unit 20 uses the AT input to the ATM cell input unit 10.
Of the M cells, valid ATM cells are counted. This AT
The M cell coefficient unit 20 may be arranged at the same position as the position where the ATM cell input unit 10 is provided, or may be arranged all at once.

(Display unit 30) The display unit 30 is the ATM.
The value counted by the cell counter 20 is displayed. The display unit 30 may be arranged at the same position as the position where the ATM cell input unit 10 is provided, or may be arranged all at once.

As the display unit 30, for example, a CRT display, LCD display, plasma display or the like can be used. The display method is 1
The 0-base display is preferable, but hexadecimal display or binary display may be used, for example.

[0024]

According to the ATM connection test apparatus having the first to seventh configurations of the present invention, the ATM cell input sections 10 provided at a plurality of positions of the ATM connection input ATM cells. Among the input ATM cells, valid ATM cells are counted by the ATM cell counting section 20, and the count value is displayed on the display section 30. By comparing the displayed values on the display unit 30, the continuity / quality of the ATM connection is tested.

In particular, the AT having the fourth to sixth configurations of the present invention
According to the M connection test apparatus, the ATM connection continuity / quality test is performed on a specific cell. Moreover, according to the ATM connection test apparatus of the seventh configuration of the present invention, the display units 30 may be collectively arranged at one place.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment relating to an ATM connection test apparatus of the present invention will be described below with reference to the drawings.

<< Outline of this Embodiment >> In this embodiment, an ATM is used.
When a specific cell for starting a test is sent to the ATM connection set via the exchange, the continuity / quality test of the ATM connection is started. After that, the AT
The number of specific cells in which a part of the header or payload data is set to a specific value is counted at a plurality of locations of the M connection. Then, when a specific cell for ending the test is flown to the ATM connection, the continuity / quality test of the ATM connection is ended.

<< System Configuration of Embodiment >> FIG. 3 shows the system configuration of an ATM exchange to which the present embodiment is applied. As shown in the figure, in this embodiment, common parts 2A to 2D and common parts 2A and 2B connected to switches 4A and 4B of two systems (# 0 [working system] and # 1 [standby system]). Individual parts (INF) 1A, 1B, 1C connected to the common part 2
Individual unit (LOOP package) 1 connected to C and 2D
It is configured with D.1E and the like.

Here, in order from the individual unit 1A, the common units 2A and 2B, the switches 4A and 4B, and the common unit 2 are sequentially arranged.
C ・ 2D → individual part 1D ・ 1E → common part 2C ・ 2D → switches 4A ・ 4B → common part 2A ・ 2B, then individual part 1B
The route leading to is described as an ATM connection to be tested.

Here, the individual unit 1 and the common unit 2 are housed in a package form in a frame (hereinafter referred to as a shelf) having a shape similar to a bookshelf (see FIGS. 4 and 5). The individual unit 1 has an ATM connection tester, has a function of terminating a synchronous digital hierarchy (SDH) format sent via a transmission system, and a transmission line dot error is an error of an ATM cell header. In order to reduce the cell loss due to the cell error control, the cell error control is performed based on the header error control information written in the cell header, and the cell synchronization detection is performed.

Here, the SDH format means that the thickness (channel capacity) of the transmission path is divided into layers (several steps) so that signals can be efficiently and flexibly transmitted upon multiplexing by the transmission system, that is, physical. It is a format divided into layers.

On the other hand, the common unit 2 has a function of converting the cell header format into a unique format shown in FIG.
It has a function of time-division-multiplexing cells input from the individual unit 1 and distributing cells to the individual unit 1. When the cell input from the individual unit 1 is input to the common unit 2, a user network interface (UNI: User-Network Interface) or a network node interface (NNI: Network) is input.
The ATM cell format of the Node Interface) is converted to the ATM cell format shown in FIG. In FIG. 2, An (n: 0 to 53) indicates how many octets from the beginning, and Dm (m: 0 to 7) indicates bit numbers in the same octet.

The interfaces of the individual unit 1 and the common unit 2 are common to the shelves, and the ATM cell has a mechanism for transmitting 8 lines of 19.44 MHz data in parallel for each of the uplink and downlink.

The signals CE and CF and the clock are also transmitted in parallel with the eight parallel cell data. Signal CE
Means a cell enable signal, and is "0" between A0 to A53 of the ATM cell shown in FIG. 2 when the ATM cell is valid. Further, the signal CF means a cell frame signal and represents the beginning of the ATM cell. That is, A0 of the ATM cell shown in FIG. 2 becomes "0". The signal clock (19M) represents a clock pulse of 19.44 MHz.

<Structure of ATM Connection Test Device> FIG. 6 is a block diagram of the structure of an ATM connection test device built in each of the individual units 1A to 1E. As shown in the figure, the ATM connection test device is
CI collation value setting unit 61, VPI / VCI value extraction timing generation unit 62, VPI / VCI value extraction unit 63, data comparison unit 64, match signal count timing generation unit 65, match number count unit 66, specific cell detection unit 67, and The display unit 30 is provided.

The components will be described below. (A) VPI / VCI collation value setting unit 61 The VPI / VCI collation value setting unit 61 determines the VPI to be collated.
Value and VCI value. Set VPI and VC
The I collation value is output to the data comparison unit 64 as 22-bit parallel data.

(B) VPI / VCI value extraction timing generation unit 62 The VPI / VCI value extraction timing generation unit 62 is a circuit (not shown) for interfacing with the outside of the individual units 1A to 1E.
Timing signals (VPI / VCI latch signal) for inputting the signals CE, CF and 19M from to extract the VPI value and VCI value of the input data (latch to the register)
Generate The generated VPI / VCI latch signal is
It is output to the VPI / VCI value extraction unit 63.

(C) VPI / VCI value extraction unit 63 The VPI / VCI value extraction unit 63 uses the VPI / VCI latch signal from the VPI / VCI value extraction timing generation unit 62 to interface with the outside of the individual units 1A to 1E. V of input data D7-0 input from a circuit (not shown)
The PI value and the VCI value are extracted (latched). The extracted VPI value and VCI value are output to the data comparison unit 64 as 22-bit parallel data. Note that the extracted VPI value and VCI value are the VPI value and VCI value in the actual data.

(D) Data comparison unit 64 The data comparison unit 64 includes a VPI / VCI collation value setting unit 61.
The VPI and VCI collation values from the VPI and VCI values are compared with the VPI value and the VCI value from the VPI / VCI value extraction unit 63. If they match, the match signal is enabled. That is, when the preset VPI and VCI collation values and the actual VPI and VCI values in the valid cell match, the match signal becomes valid. The match signal is output to the match number counting unit 66.

(E) Match signal count timing generator 65 The match signal count timing generator 65 generates timing (count timing) for determining the match signal output from the data comparator 64. The generated count timing is output to the match count counting unit 66.

Note that the determination of the coincidence signal means that the VPI / VCI value extraction unit 63 performs VPI in the valid cell section.
It means that the extraction of the value and the VCI value is completed, and then the data comparison in the data comparison unit 64 is also completed, and whether the match signal is enabled or disabled is determined. In this way, the coincidence signal count timing generation unit 65 generates the timing at which it is determined whether or not they coincide.

(F) Matching Count Counting Unit 66 The matching count counting unit 66 receives control information for starting or stopping counting of the matching count from the specific cell detection unit 67.

When the control information for starting the count is input, the count value up to that point is cleared, and at the timing notified by the match signal count timing generator 65, the match signal from the data comparator 64 is sent. Is enabled, it is determined that the VPI value and VCI value in the actual data match the collation value, and the number of times is counted. More specifically, if the match signal is enabled when the count timing is notified from the match signal count timing generation unit 65, the count value is incremented by +1.
Only increase. On the other hand, if it is not enabled, that is,
If they do not match, the count value is not changed.

On the other hand, when the control information for stopping the count is input, the count value of the number of coincidences is held. The count value indicating the number of matches is output to the display unit 30 as binary parallel data.

(G) Specific cell detecting section 67 The specific cell detecting section 67 determines that the test is started based on input data D7-0 input from a circuit (not shown) for interfacing with the outside of the individual sections 1A-1E. Detect specific cells for test termination. The specific cell here means an ATM cell whose payload type (PT) is "001" or "002", for example.

First, when the specific cell for starting the test is detected, the coincidence count counting unit 66 is notified of the control information for starting the counting of the coincidence count. When the specific cell for ending the test is detected, the coincidence count counting unit 66 is notified of the control information for stopping the counting of the coincidence count.

Further, when the specific cell is detected, the display unit 30 is notified that the specific cell has passed. In the present embodiment, the test starting specific cell and the test ending specific cell are different, but the same may be used. That is, the test is started when such a specific cell is received for the first time, and ended when it is received for the second time.

(H) Display Unit 30 The display unit 30 displays the number of matches (count value) output from the match number counting unit 66 so that it can be seen by a person. As a display method, binary parallel data is
The ED or the lamp displays the binary number as it is, or the decoder (not shown) displays the decimal number or the hexadecimal number.

The display unit 30 receives from the specific cell detection unit 66,
The display is cleared when the control information indicating that the specific cell for starting the test is detected is received. Further, when the specific cell detection unit 66 receives a notification of the control information indicating that the specific cell for ending the test is received, the display is stopped (held).

<Operation Processing of ATM Connection Testing Apparatus> Next, the operation processing of the ATM connection testing apparatus will be described with reference to FIG. First, in process step S701, the VPI / VCI collation value setting unit 61 sets collation values for VPI and VCI. Here, although not shown, it is assumed that a specific cell for starting a test is flowed and the ATM connection continuity / quality test is started.

In the next processing step S702, VPI
The VCI value extraction unit 62 extracts the VPI value and the VCI value from the input data. Then, the processing step S70
In 3, the data comparison unit 64 compares the collation value set in S701 with the extracted value extracted in S702.

Next, when the collation value and the extracted value match, the match count counting unit 66 increments the count value indicating the match count by +1 (processing steps S704 and S70).
5). On the other hand, if the collation value and the extracted value do not match, the count value does not change (processing step S704).

Here, it is checked whether or not the specific cell is received (processing step S707). If the specific cell is not received, the processing from the processing step S702 is repeated again.

If it is determined in processing step S707 that the specific cell has been received, the display on the display unit 30 is stopped (held) (processing step S708). Then, when the specific cell for ending the test is flowed, the count value of the coincidence number counting unit 66 is cleared (processing step S70).
9).

<Operation / Effect of this Embodiment> According to this embodiment, a specific cell indicating the start and end of the test is flowed at the start and end of the ATM connection test. Then, the failure point of the ATM connection 8 is specified by comparing the numerical values displayed on the display sections 30 of the three ATM connection test apparatuses provided in the individual section 1A, the individual section 1D, and the individual section 1B. For example, if the display numerical values of the display unit 30 of the individual unit 1A and the display unit 30 of the individual unit 1D are both 500 and the display numerical value of the display unit 30 of the individual unit 1B is 498, the individual unit 1D to the individual unit 1B are reached. It is identified that there is an obstacle in the route. Similarly, if the display numerical values of the display unit 30 of the individual unit 1A are both 500 and the display numerical values of the display unit 30 of the individual unit 1D and the display unit 30 of the individual unit 1B are both 498, the individual units 1A to 1D are displayed. It is identified that there is an obstacle in the route leading to.

It should be noted that the failure location can be specified by simply looking at the passage of the specific cell without comparing the displayed values on the display unit 30. It is also possible to test between the trunk lines by comparing the counter values between the ATM exchanges provided with the ATM connection test device.

[0057]

The AT according to the first to sixth configurations of the present invention
According to the M connection test apparatus, by comparing the numbers of cells of a plurality of display units provided in the middle of the ATM connection, the ATM connection processing function is not used and the ATM connection processing function is not used.
It is possible to easily identify the faulty part of the connection. Moreover, the test result can be easily confirmed because it is only necessary to compare the magnitude of the numerical values displayed on the display unit.

In particular, according to the ATM connection test apparatus having the fourth to sixth configurations, since the specific cell detecting unit is provided, the causal relationship between the specific cell and the fault location of the ATM connection can be clarified.

Furthermore, since the ATM connection test apparatus according to the first to sixth configurations of the present invention can be configured only by hardware, it is particularly effective in the test at the system startup.

On the other hand, according to the ATM connection test apparatus of the seventh configuration of the present invention, since the display section is integrated in one place, it is easy to compare the number of cells, and the OAM cell processing function is based on the comparison result. Without using
It is possible to easily identify the faulty part of the ATM connection. Moreover, the test result can be easily confirmed because it is only necessary to compare the magnitude of the numerical values displayed on the display unit.

[Brief description of drawings]

FIG. 1 is a principle diagram of an ATM connection test apparatus of the present invention.

FIG. 2 is a diagram showing an ATM cell format.

FIG. 3 is a system configuration diagram of an ATM exchange to which this embodiment is applied.

FIG. 4 is an external view of a shelf in the example.

FIG. 5 is a front view of the shelf of the embodiment.

FIG. 6 is a configuration block diagram of an ATM connection test apparatus according to an embodiment.

FIG. 7 is an operation processing flow of the ATM connection test apparatus of the embodiment.

FIG. 8 is a diagram showing an example of a test route of an ATM connection.

FIG. 9 is a diagram showing an example of an ATM connection test route when a test apparatus is used.

FIG. 10 is a diagram (No. 1) showing a test route when the test route shown in FIG. 9 is divided.

FIG. 11 is a diagram (No. 2) showing the test route when the test route shown in FIG. 9 is divided.

[Explanation of symbols]

 1 Individual part 2 Common part 4 ATM switch 8 ATM connection 10 ATM cell input part 20 ATM cell counting part 30 Display part 40 Count value clearing part 50 Specific cell detecting part 61 VPI / VCI collation value setting part 62 VPI / VCI value extraction timing Generation unit 63 VPI / VCI value extraction unit 64 Data comparison unit 65 Matching signal timing generation unit 66 Matching frequency counting unit 67 Specific cell detection unit

Claims (7)

[Claims] 1. An ATM connection testing device, which is provided in the middle of an ATM connection which is a communication path of an ATM cell, for testing the continuity and quality of the ATM connection, comprising: an ATM cell input section for inputting the ATM cell. Among the ATM cells input to the ATM cell input section,
An ATM connection test apparatus comprising: an ATM cell counting section for counting valid ATM cells; and a display section for displaying a value counted by the ATM cell counting section. 2. The ATM connection test apparatus according to claim 1, further comprising a count value clearing unit for clearing a count value counted by the ATM cell counting unit. 3. The ATM cell counting section counts only the ATM cells in which the data stored in the header or the payload has a predetermined value among the valid cells. ATM connection test device described in. 4. The ATM input to the ATM cell input section
Providing a specific cell detection unit that detects a specific cell from the cell,
The ATM connection test apparatus according to claim 1, wherein when the specific cell is detected by the specific cell detection unit, the display unit displays that the specific cell has passed. 5. The ATM input to the ATM cell input section
Providing a specific cell detection unit that detects a specific cell from the cell,
3. The ATM connection test apparatus according to claim 1, wherein the ATM cell counting unit starts or stops counting of the ATM cells when a specific cell is detected by the specific cell detection unit. 6. The ATM input to the ATM cell input section
Providing a specific cell detection unit that detects a specific cell from the cell,
The ATM connection test apparatus according to claim 2, wherein the count value clearing unit stops the display of the display unit when the specific cell is detected by the specific cell detecting unit. 7. An ATM cell input section, which is provided in the middle of an ATM connection which is a communication path of an ATM cell, for inputting the ATM cell, and an ATM cell input to the ATM cell input section,
An ATM connection test, comprising: an ATM cell counter for counting valid ATM cells; and a display for displaying a value counted by the ATM cell counter, for testing continuity and quality of the ATM connection. apparatus.