JPH03268545A - Terminal adapter - Google Patents

Abstract

PURPOSE:To execute a loop test only on the calling side by sending loop back information from a calling side terminal adapter by means of a user information transmitting function and automatically forming an information channel loop to a line by a called side terminal adapter. CONSTITUTION:When a loop test mode is set up by an input part 4, a call setting message is sent from a calling side terminal equipment to an ISDN network exchange and loop-back instructing information is included in the call setting message as user information. The terminal adapter on the called side analyzes the user information, and when the loop-back instruction information is included in the user information, a loop is formed by switching a cross switch 10. When the ISDN information channel is connected, the calling side terminal adapter allows test data to flow and executes a loop test.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a terminal adapter connected between a terminal and a digital network for interface exchange, and particularly to one that facilitates loop testing of the terminal adapter.

(Prior Art) In recent years, ISDN (Integrated Services Digital Network) has been provided, and opportunities to use it are increasing.

However, there are still many data communication devices in use that do not have an ISDN interface, that is, have existing data communication interfaces that are not compatible with ISDN. Therefore, terminal adapters have been proposed in order to accommodate data communication equipment with existing data communication interfaces that are not compatible with ISDN. Terminal adapters are compatible with existing interfaces that are not compatible with ISDN, such as ■. 24, X.
21 etc. with an ISDN interface, and enables existing equipment to communicate via ISDN. This terminal adapter is often used for purposes similar to modems in analog networks (telephone line networks, leased lines).

Therefore, the terminal adapter may provide a loop test function as a terminal and line test and maintenance function.

For loop testing, test data emitted from the terminal's outgoing line is looped back inside the terminal adapter connected to this terminal and sent to the terminal's receiving line, and a loop test is performed between the terminal and the terminal adapter connected to it. After establishing a communication channel between the first loop test and the calling terminal and the receiving terminal, the test data transmitted from the transmission line of the calling terminal is connected to the calling terminal. The terminal adapter sends the test data to the terminal adapter connected to the receiving terminal via the digital network to which this terminal adapter is connected, and the test data is looped back inside the terminal adapter connected to the receiving terminal and sent to the originating terminal. A second loop test is performed including between the terminal adapter connected to the calling side terminal and the terminal adapter connected to the called side terminal.
There is a loop test.

By the way, the first loop test is a test between the terminal and the terminal adapter connected to it, so 1
The second loop test is a test that involves the calling terminal and the called terminal which is far away from the calling terminal. A maintenance person is assigned to each side terminal, the called side is set to test mode, and test data is sent from the calling side terminal, so at least two maintenance people are required, which is not efficient. There was a problem.

(Problem to be Solved by the Invention) As described above, in conventional equipment, when performing a second loop test, maintenance personnel manually configure the loop test settings for the terminal adapter on the called side, and then perform another loop test. Since this is often carried out by maintenance personnel making calls from the terminal adapter on the calling side, at least two maintenance personnel are required for the second loop test, which poses a problem of poor efficiency.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a terminal adapter that allows a single maintenance worker to reliably perform a loop test including a second loop test from only one terminal.

[Structure of the invention]

(Means for Solving the Problems) In order to achieve the above object, according to the present invention, in a terminal adapter connected to a digital network capable of transmitting user information at the time of call setup, loopback instruction information is transmitted at the time of call origination. means for including and transmitting the user information in the user information;
and means for forming a loop path of an information channel through the digital network in response to receiving the loopback information.

(Operation) When the terminal adapter on the calling side sends the loop bank instruction information included in the user information, the loop adapter on the receiving side that receives this information automatically forms a loop path for the information channel.

(Embodiment) FIG. 1 is a block diagram showing one embodiment of a terminal adapter according to the present invention.

Note that the terminal adapters are connected between the terminal devices TUI and TU2 and the I5DN network 100, as shown in FIG. Here, when the terminal device TUI is the terminal device on the calling side and the terminal device TU2 is the terminal device on the called side, the terminal adapter TAI installed between the terminal device TUI and the l5DN network 100 is the terminal device on the calling side. The terminal adapter TA2 installed between the terminal device TU2 and the 15DN network 100 is called the called terminal adapter.

Now, in Figure 1, the terminal adapter has a microprocessor (CPU) 1, an input/output interface 2,
Display section 3, human power section 4, memory 5, terminal interface 6
, selector switch 7, serial interface 8, speed matching section 9, cross switch 10. It is equipped with an I5DN-3 point interface circuit 11 and a CPU bus 12.

Here, the CPU 1- controls the entire apparatus based on a program stored in the memory 5. This CP
A CPU bus 12 is connected to the UI.

The display section 3 is composed of an LCD, an LED, etc., and displays various information. The input section is composed of dial keys and function keys, and is used for manually dialing numbers and setting each function. The display section 3 and the human power section 4 are connected to the CP via the human power output interface 2.
Connected to U bus 12.

The terminal interface is composed of, for example, an R3-232C interface, and converts electrical signal levels.

The changeover switch 7 distributes the signal from the terminal interface 6 to the serial interface 8 or the speed matching section 9 according to instructions from the CPUI.

The serial interface 8 converts the serial signal of the terminal interface and the parallel signal of the CPU bus.

Further, the speed control section 9 converts the signal speed of the terminal interface and the signal speed of ISDN. The signal speed of the terminal interface is 300 bps ~
The signaling rate of I5DN is 64 kbps (information channel), although 19200 bps is used.

The cross switch 10 performs the following connection control according to instructions from the CPUI. That is, in normal communication mode, line TA is connected to line TB, line RB is connected to line RA, and in terminal side test loop mode, that is, in the first loop test mode, line TA is connected to line RA. In the test loop mode on the line side, that is, in the second loop test mode, line RB is connected to line TB.

The l5DN-5 point interface circuit 11 multiplexes information channels and signal channels and connects them to the l5DN network 10.
Connect to 0.

Next, the operation of this embodiment will be explained with reference to the flowchart shown in FIG. The operation shown in FIG. 3 is the operation when the test loop mode on the line side, that is, the second loop test mode is set.

First, in the terminal adapter on the calling side, input section 4
Set the loop test mode using (Step 1)
01). Then, a call is made by manually inputting the destination phone number from the human power section 4 (manual call) or manually inputting the destination phone number from the terminal via the serial interface 8 (automatic call) (step 102). At this time l
A call setup message is sent from the calling side terminal device to an exchange (not shown) of the 5DN network, and loopback instruction information is inserted as user information in this call setup message.

FIG. 4 shows the format of this call setup message. As is clear from FIG. 4, in the call setup message, code information indicating that it is a call setup message is stored in the first octet, and thereafter, each information element, ie, transmission capability, channel identifier, calling number, called number,
Information elements of user information are stored.

The user information information element includes an information element identifier, an information element length,
Protocol identification information and loopback instruction information related to this invention are stored.

When the terminal adapter on the called side receives a signal in the format shown in FIG. 4, it performs a call receiving operation (step 103). At this time, the terminal adapter analyzes the user information and, if loopback instruction information is included, forms a loop by switching the cross switch 10 (
Step 104). Specifically, in this case, the test loop mode on the line side, that is, the second loop test mode, is formed by connecting the line RB to the line TB. After that, in response to the call, l5
Connect the DN information channel end-to-end (
Step 105).

When the I5DN information channel is connected, the terminal adapter on the calling side performs a loop test by flowing test data.

When the loop test is completed and a disconnection message is generated from the calling side terminal adapter, the line is restored by this disconnection message, and the called side terminal adapter releases the loop (step 108).

Although FIG. 3 shows the test loop mode on the line side, that is, the second loop test mode, in the case of the test loop mode on the terminal side, that is, the first loop test mode, the mode from the input section 4 According to the settings, the first loop test can be performed by connecting line TA to line RA and, in this state, flowing test data from the terminal device connected to this terminal adapter.

In this way, according to this embodiment, both the first loop test and the second loop test can be performed by one maintenance person from one terminal adapter.

〔Effect of the invention〕

As explained above, according to the present invention, the calling side terminal adapter uses the user information transmission function to send loopback information, and the called side terminal adapter that receives this information automatically transmits the information to the line. Since the system is configured to form a channel loop, a loop test can be performed with just one maintenance person on the calling side, making it extremely efficient.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of the terminal adapter of the present invention, FIG. 2 is a diagram of a communication system configured using the terminal adapter, and FIG. 3 is a flowchart explaining the operation of the terminal adapter of the present invention. FIG. 4 is a format diagram of a call setup message used in this embodiment.

Claims (1)

[Scope of Claims] In a terminal adapter connected to a digital network capable of transmitting user information at the time of call setup, means for transmitting loopback instruction information included in the user information at the time of call origination; and means for forming a loop path of an information channel through the digital network in response to receiving information.