JPH0226431A - Loop back test system for hdlc procedure line - Google Patents

Abstract

PURPOSE:To facilitate fault segmentation by returning, when a testing data pattern set beforehand to a self-station is detected in line normality testing information received from an HDLC procedure line, the same data as this to the line through which the information is sent as a response to this information. CONSTITUTION:Exchange stations corresponding to HDLC lines 101 and 102 are equipped with a function to respond only to specific test pattern data in a TEST command (a) and return a TEST response (a) corresponding to the data to the pair of HDLC procedure lines 101 and 102 to communicate through a packet exchange network 100. Consequently, a fault occurring interval can be defined more minutely and a returning point at the time of a test can be controlled by the test pattern data designated by the TEST command (a) from the side of one HDLC procedure line. Thus, operation on the fault segmenting can be simplified.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention is applicable to communication between computers or between a computer and a terminal having an HDLC procedure for communicating via the packet assembly/disassembly function (hereinafter referred to as PAD function) of a packet switching network. Regarding the return test method.

[Conventional technology]

Conventionally, in a network where HDLC procedure lines communicate via a packet-switched network, when troubleshooting between a computer, a packet-switched network, and a terminal is performed,
As shown in FIG. 3, the control unit 11 on the computer 1 side sends the rTEsT command J4 in the HDLC procedure to the terminal 3.
Terminal 3 sends and responds to this rTEsT command ``4.
(7;) rTEST response from the control unit 31 of 5
was received by the computer and checked, and the normality of the connection between the computer 1 and the terminal 3 was confirmed by comparing the sent and received test data and checking whether there was a match or mismatch. In this case, the PAD function section 21 within the packet switching network 2 only provides a transparent communication function.

[Problem to be solved by the invention]

In the conventional fault isolation method described above, the normality of the connection between the computer 1 and the terminal 3 can be confirmed, but
When a failure is detected, the packet switching network 2 and the computer 1. This has the disadvantage that it is not possible to detect which side of the terminal 3 a failure is occurring.

[Means to solve the problem]

The loopback testing method for HDLC procedure lines of the present invention is such that each switching center that accommodates an HDLC procedure line in a packet switching network and has a packet assembly/disassembly function is used to test the line normality of signals received within the network or from the line. When a test data pattern preset for the local station is detected in the information, the same data pattern as the set test data pattern is sent to the network from which the information was sent as a response to the information. Alternatively, it is characterized by comprising means for returning the data to the line.

〔Example〕

Next, the present invention will be explained with reference to the drawings.

Referring to FIG. 1, a control unit has a function of transmitting the rTEST command in the HDLC procedure and a function of receiving the rTEST response, comparing and checking the transmitted and received test pattern data, and determining that it is normal if it matches, and that it is abnormal if it does not match. 108 is connected to the primary station 103 of the packet switching network 100 via the HDLC procedure line 101.
PADA phase function 09. One logical channel 105 in the packet switching network 100, PAD function unit 1 of the secondary station 104
10. It is connected to an HDLC terminal 106 via a terminal-side HDLC line 102.

Computer 107 and HDL without repeat test
When performing normal communication between the C terminals 106, data is transmitted and received according to the HDLC procedure using a connection configuration from the computer 107 to the terminals 106.

When performing a return test, the computer 1070 control unit 108 controls the PA of the primary station 103 as shown in FIG.
If you want to call back with DA phase function 09, use "TEST command a", and if you want to call back with PAD function section 110 of secondary station 104, send rTEST command b", and then use HDLC.
When the terminal 106 wants to return the call, it sends an rTEST command C'' having contents other than the above-mentioned rTEST command a'' and rTEST command b''. P of primary station 103
In the ADA phase function 09, when the rTEsT command a containing the preset test pattern data a is received, the control unit 111 detects this and sends the rTEsT command to the command sending side, that is, the HDLC procedure line)01.
If an rTEsT response a containing the same test pattern data a is detected, and an rTEST command with other test pattern data is detected, the normal PA
The D function assembles a packet containing the test pattern data and sends it toward the destination (108) of the packet switching network. In the PAD function unit 110 of the secondary station 104, when the control unit 112 detects the test pattern data b of the preset rTEsT command b when disassembling the packet received from the packet switching network 100, this is converted into the same test pattern data. The network 100 assembles the packets containing b.
Send it back to 2 in the PADA phase function 09 of the primary station 103.
The bucket received from the next station 104 is decomposed and rTE
sT command b' and rTEST response b including the same test pattern data b are transmitted to the computer 107. When the rTEST command C is different from both rTEST commands a and bJ, the rTEST command C is sent to the terminal 106 through packet assembly 2, as in the past, and the same test as the one received by the control unit 113 is sent. "rTEST response C" having pattern data C is returned. This test pattern data C
may be different from the test pattern data a and b, and is therefore not limited to the number of types.

〔Effect of the invention〕

As explained above, the present invention provides rTEST to a switching station corresponding to each of these HDLC lines for a pair of HDLC procedure lines that communicate via a packet switching network.
By providing a function that responds only to specific test pattern data in a "command" and returns an "rTEST response" corresponding to that data, it is possible to more precisely limit the section where a failure occurs, and the "T
Since the turning point during the test can be controlled by the test pattern data specified by the "EST command", the above operation for fault separation can be simplified.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of an embodiment of the present invention, and FIG. 2 shows the rTBsT command J on the HDLC procedure line on the same side.
Figure 3 showing the format of “rTEST response”
The figure is a block diagram of a conventional fold-back test method.

Claims (1)

[Claims] Each switching station that accommodates an HDLC procedure line and has packet assembly/disassembly functions within a packet switching network has a message that has been set in advance for the own station within the network or within the line health test information received from the line. The apparatus further comprises means for, when a test data pattern is detected, returning a data pattern identical to the set test data pattern to the network or line from which the information was sent as a response to the information. Features HDLC procedure line loopback test method.