JPH05136782A - Isdn packet communication matching propriety testing system for isdn packet communication - Google Patents

Abstract

PURPOSE:To provide the ISDN packet communication matching propriety testing system for the ISDN packet communication in which the communication matching propriety test of the X25 protocol is implemented on a D-channel of an ISDN. CONSTITUTION:The system is made up of a tester 20 testing the X25 protocol, an ISDN call control section 10 receiving a control signal from an ISDN call control test section 22 and setting a D channel packet of the ISDN to a tested terminal equipment 11, an address conversion section 12 connecting to the ISDN call control section 10 and a tester basic section 21, receiving a test message outputted from the tester basic section 21 and implementing the conversion from a LAPB form into a LAPD form or vice versa as to the address, and an ISDN transmission reception section 13 receiving a test message from the address conversion section 12 via the ISDN call control section 10 and giving it to the tested terminal equipment 11 and receiving a test result signal from the tested terminal equipment 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention enables ISDN (Integrated Digital Services Network) ISDN which is capable of conducting a communication consistency test of the X25 protocol on a D channel packet terminal connected to a S / T point of a subscriber system. The present invention relates to a packet communication integrity test system.

X25 is a packet switched network DDX-P
Is a communication control protocol of. The communication consistency test is a test for verifying whether or not the terminal is performing the state transition specified in the technical standard for the received message in each state in ISDN call control and packet communication.
(Setup), to verify the response when various messages are received.

[0003]

2. Description of the Related Art When a terminal (TE) is used for DDX-P (packet switching network), the X25 protocol is used.
When performing the communication consistency test of the X25 protocol, the commercially available tester 1 and the terminal under test 2 are connected as shown in FIG. Reference numeral 3 is a transmission line that connects the two. Generally, a total count of 10 is used as a conformance test for verifying the X25 procedure as a data network.
As many as 0 test items are installed in the commercial tester 1,
The X25 protocol as a DDX-P packet network is tested. When the terminal under test 2 is performing the state transition specified in the X25 protocol of DDX-P, the test passes.

[0004]

Although the conventional communication consistency test has been carried out on the terminals of the DDX-P packet network, the D channel of ISDN (hereinafter simply abbreviated as D-ch).
There was nothing that could be achieved above. Therefore, ISDN D
When trying to execute the X25 conformance test on the -ch, the IS that performs ISDN call control as shown in FIG.
A DN tester 4 and an external tester 5 connected to its external input are required. In the figure, 6 is a terminal under test (TE), 7
Is an S / T that connects the ISDN tester 4 and the terminal under test 6
It is a point interface.

In such a connection state, it is necessary to program the X25 LAPB (layer 2) frame into the LAPD frame by the external tester 5 and give it to the ISDN tester 4. In the test embodiment, the ISDN tester 4 controls the call. When it becomes a D-ch packet as a result, it is necessary to start the external tester 5 having the X25 conformance test and perform the test.

At present, services of INS (NTT ISDN) packet communication are also provided, and in order to ensure communication consistency with the data network by the existing X25, it is desired to realize a system capable of confirming the communication. There is.

Further, the frame structure on D-ch is different from that of a normal data network. In the frame structure, the address format is extended X25LAPB (hereinafter referred to as LAP) of the data network.
(Denoted as B) and the ISDN LAPD. Here, LAPB is an X25 layer 2 protocol, and LABD is an ISDN layer 2 protocol.

As another problem, in the D-ch, signal packets for call control and user information packets are exchanged with the user network.
It is necessary to perform packet call control, and it is necessary to be able to do it in the communication consistency test.

The present invention has been made in view of the above problems, and an object thereof is to provide an ISDN packet communication consistency test system capable of performing a communication consistency test of the X25 protocol on the D-ch of ISDN. There is.

[0010]

FIG. 1 is a block diagram showing the principle of the present invention. In the figure, 20 is a tester basic unit 21 for testing the X25 protocol, ISDN call control sequence is stored, ISDN for D-ch packet setting.
A tester 10 comprising an ISDN call control test unit 22 for performing a call control test receives an control signal from the ISDN call control test unit 22 and sets an ISDN D-ch packet for the terminal under test 11, 12 Is the ISDN
Address conversion that is connected to the call control unit 10 and the tester basic unit 21, receives a test message output from the tester basic unit 21, and converts the address from the LAPB format to the LAPD format or from the LAPD format to the LAPB format. The section 13 is an ISDN transceiver for receiving the test message from the address conversion section 12 via the ISDN call control section 10 and giving it to the terminal under test 11, and for receiving the test result signal from the terminal under test 11. ..

[0011]

First, the ISDN call control test unit 22 sends D-c
The sequence signal for h packet setting is ISD
The D-ch packet is sent to the terminal under test 11 via the N call control unit 10 and is subjected to ISDN call control. When the D-ch packet is set, this time, the tester basic unit 21 sends out a sequence for the conformance test of X25.

This sequence is input to the address conversion unit 12 and is converted from LAPB to LAPD, and then I
It is given to the SDN call control unit 10. ISDN call control unit 1
0 gives the test sequence after address translation to the terminal under test 11 via the ISDN transmitting / receiving section 13.

The response signal from the terminal under test 11 is ISD.
It enters the address conversion unit 12 via the N transmission / reception unit 13, the address conversion unit 12 again performs conversion from LAPD to LAPB, and the result is given to the tester basic unit 21. Thus, according to the present invention, the communication consistency test of the X25 protocol can be performed on the D-ch of ISDN.

[0014]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 2 is a diagram showing a connection state of the present invention.
The same parts as those in FIG. 1 are designated by the same reference numerals. Tester (Protocol Tester: PT) 20 and Terminator (NT) 3
The S / T point interface 31 is set between 0.
The terminal under test 11 is connected to the S / T point interface 31.

FIG. 3 is a block diagram showing the configuration of an embodiment of the present invention. The same parts as those in FIG. 1 are designated by the same reference numerals. In the figure, 20 is a tester for performing an X25 protocol conformance test. This tester 20
It is composed of a tester basic unit 21 and an ISDN call control test unit 22.

The tester basic unit 21 is composed of an OS (operating system), a test common unit, an X25 test group, and an individual test control unit. Reference numeral 23 is a display unit for displaying information connected to the tester basic unit 21, and 24 is a keyboard for inputting various commands. 10 is ISD
ISD which receives a control signal from the N call control test unit 22 and sets an ISDN D-ch packet in the terminal under test 11.
It is an N call control unit.

Reference numeral 12 is connected to the ISDN call control unit 10 and the tester basic unit 21 (the response determination unit 45 in the figure), receives a test message output from the tester basic unit 21, and changes its address from the LAPB format to the LAPD format. An address conversion unit that performs conversion or conversion from the LAPD format to the LAPB format.

The ISDN transmission / reception unit 13 receives the test message from the address conversion unit 12 via the ISDN call control unit 10 and gives it to the terminal under test 11, and the test result from the terminal under test 11. It is composed of an ISDN message receiving unit 13b which receives a signal. These ISDN message sending units 13a and I
The SDN message receiving unit 13b is the ISDN call control unit 10
Connected with.

Numeral 40 is an X sent from the tester basic unit 21.
A protocol control unit for controlling 25 test sequences,
Reference numeral 41 denotes a timer unit that monitors the response message time during the test execution, and is connected to the protocol control unit 40.
42 is an X25 message sending unit that receives the X25 message from the protocol control unit 40 and sends it to the terminal under test (DTE) 43, 44 is an X25 message receiving unit that receives the test result from the terminal under test 43, and 45 is an X25 message. It is a response determination unit that receives the output of the reception unit 44 and the output of the address conversion unit 12 and determines whether it is a designated response to the X25 test message. X25
The output of the message receiving unit 44 is the protocol control unit 40.
And the response determination unit 45.

The test sequence of the protocol control unit 40 is also given to the address conversion unit 12. The part above the broken line is for DDX-P, and the part below the broken line is for ISDN. The operation of the system configured as described above will be described below.

First, the operation of the conventional DDX-P will be described. This operation is the same as the conventional X25 conformance test. The tester basic unit 21 controls the selection, execution, continuous operation, etc. of the entire test, and the control, transmission, and determination of each message operate as the function of each block. That is, according to the test sequence designated by the tester basic unit 21, the X25 message transmitting unit 42 transmits a message to the terminal under test 43 while the protocol control unit 40 manages the message generation time. The terminal under test 43 returns a response. This response is X25
The message is received by the message receiving unit 44 and passed to the response determining unit 45.

The response determination unit 45 checks whether the received response is the designated response. When the responses to all the X25 messages are designated responses, the response determination unit 45 notifies the tester basic unit 21 that the test has passed.
To do.

FIG. 4 is a diagram showing a sequence example of a normal X25 conformance test. First, a layer 2 link is established between the terminal under test (DTE) 43 and the home line terminating device (NT: here, tester 20) (). next,
Restart for system initialization (RESTAR
T) Perform procedure (). Next, a packet link is set up (), a test message is sent, and a test procedure for receiving the response is started (). After the series of tests is completed, the packet link is released ().

Next, the operation of the X25 conformance test on the D-ch of ISDN will be described. First,
It is necessary to set the D-ch packet so that the terminal under test 11 can receive the frame format. This D-
The ch packet is set by ISDN call control.

Specifically, the ISDN call control sequence is stored in the ISDN call control test unit 22, and the control data output from this ISDN call control test unit 22 is tested via the ISDN call control unit 10. S / of terminal 11
Given to the T-point interface. As a result, the terminal under test 11 is set as a D-ch packet.

FIG. 5 is a diagram showing a sequence of ISDN D-ch packet setting. First, the test common unit of the tester basic unit 21 in the tester 20 activates the ISDN call control unit 10. The ISDN call control unit 10 reads out a necessary test sequence from the ISDN call control test unit 22 and outputs D-c.
h A packet information element setup (SET UP) message is generated and transmitted from the ISDN message transmitter 13a to the terminal under test 11. The terminal under test 11 responds to this, and performs call control as a D-ch packet.

That is, the D-ch call control is received from the NT to the TE (). Then, the TE 11 requests the NT for the ID (). An ID is assigned from the NT to the TE 11 (), and a layer 2 link is set (). Next, a response to the call control is performed (), and a D-ch packet is set between TE11 and NT ().

By the above procedure, the setting of the D-ch packet is completed. The subsequent X25 conformance test sequence is the same as in FIG. The X25 test group of the tester basic unit 21 activates a normal X25 conformance test. This output is given from the protocol control unit 40 to the address conversion unit 12.

The address translation unit 12 translates a LAPB address into a LAPD address. Figure 6 shows LABP
It is a comparison diagram of an address and a LABD address. LAPB
The address consists of 1 byte, and the LAPD address is 2
It consists of bytes. That is, the LAPB format is composed of the DTE address 51 and the data area 52. The LAPD format has an address area of 53, 54
2 bytes and a data area 55.

In the address areas 53 and 54, EA is an address field extension bit, CR is a command response field bit, SAPI is a service access point identifier, and TEI is a terminal termination identifier.

The sequence message converted from the LAPB format to the LAPD format by the address conversion unit 12 enters the ISDN message transmission unit 13a via the ISDN call control unit 10. The ISDN message transmitter 13a gives the received message to the terminal under test 11.

The terminal under test 11 makes a state transition corresponding to the D-ch packet sequence and responds to the test message in the same manner when it enters the test state. The response is received by the ISDN message receiving section 13b and I
It is given to the SDN call control unit 10. ISDN call control unit 1
0 passes the received message to the address conversion unit 12. The address conversion unit 12 reversely performs address conversion from LAPD to LAPB, and gives the message to the response determination unit 45. The response determination unit 45 determines whether the received message is a designated response. The determination result is notified to the tester basic unit 21.

[0034]

As described above in detail, according to the present invention, ISDN call control is performed prior to the X25 test to set a D-ch packet, and then an X25 conformance test is performed on the ISDN D-ch. Can be applied to the ISDN packet communication consistency test system capable of performing the communication consistency test of the X25 protocol on the ISDN D-ch.

[Brief description of drawings]

FIG. 1 is a principle block diagram of the present invention.

FIG. 2 is a diagram showing a connection state of the present invention.

FIG. 3 is a configuration block diagram showing an embodiment of the present invention.

FIG. 4 is a diagram showing a sequence example of a normal X25 conformance test.

FIG. 5 is a diagram showing a sequence of ISDN D-ch packet setting.

FIG. 6 is a comparison diagram of a LAPB address and a LAPD address.

FIG. 7 is a connection conceptual diagram of a conventional communication consistency test.

FIG. 8 is a connection conceptual diagram of a test system on an ISDN channel according to a conventional method.

[Explanation of symbols]

 10 ISDN call control unit 11 terminal under test 12 address conversion unit 13 ISDN transmission / reception unit 20 tester 21 tester basic unit 22 ISDN call control test unit

Claims (1)

[Claims] 1. A tester basic unit (21) for testing an X25 protocol and an ISDN call control sequence are stored, and D
A tester (20) including an ISDN call control test unit (22) for performing an ISDN call control test for setting a channel packet, and a terminal under test (11) receiving a control signal from the ISDN call control test unit (22). An ISDN call control unit (10) for setting an ISDN D channel packet, the ISDN call control unit (10) and a tester basic unit (21)
Connected to the tester basic part (21) and receiving the test message output from the tester basic part (21), the address is converted from the LAPB format to the LAPD format or from the LAPD format to the LAP.
An address conversion unit (12) for converting to the B format and an IS test message from the address conversion unit (12).
The terminal under test (1) is received via the DN call control unit (10).
An ISDN communication consistency test system including an ISDN transmitting / receiving unit (13) which receives the test result signal from the terminal under test (11) while being given to 1).