JPS639415B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a line quality monitoring system, and particularly to a line quality monitoring system in a communication network in which terminal equipment is accommodated in an exchange via a communication line.

In order to maintain the quality of communication services provided by communication networks such as data exchange networks, it is necessary to measure and monitor the transmission quality of the communication channels provided by the communication network to subscribers so that it is always maintained at a certain level. .

FIG. 1 is a diagram showing an example of a conventional intra-network transmission quality measurement method in a data exchange network. In FIG. 1, a communication path to be measured is set up between the terminal devices T of the data exchange network N accommodated in the data exchange 4 of the terminal device 1 via the communication line L, and an error rate measuring device M is connected in place of the terminal device 1. Then, measurements can be made by exchanging measurement signals between the measuring devices, or by connecting the communication line back at one end of the communication path under test and receiving the measurement signal from the error rate measuring device M connected to the other end. Measurements are made by transmitting and receiving signals that are sent back.

According to the conventional in-network transmission quality measurement method as described above, the communication path to be measured cannot be used for data communication services during the measurement period, causing inconvenience to subscribers. Therefore, it is impossible to perform such measurements frequently and is only performed when some kind of abnormality occurs in the communication line, making it difficult to accurately grasp the quality state of the communication line. Furthermore, when carrying out the above-mentioned measurements, it requires a great deal of effort and time, such as moving the measuring device to the subscriber to be measured and setting up the communication path to be measured. It is difficult to make measurements in

It is an object of the present invention to eliminate the drawbacks of the conventional in-network transmission quality measurement method as described above, and to provide a line that can be measured and monitored so that the transmission quality of the communication channel provided to subscribers by the communication network is always maintained at a constant level. The aim is to realize a quality monitoring method.

The purpose of this is in a communication network in which terminal equipment is housed in an exchange using a communication line.The exchange is equipped with a detection unit and a quality measurement unit that detect call origination and termination on the communication line, and when there is no communication, the exchange When the detection section detects the no-communication signal, the quality measurement section is connected to the communication line in the no-communication state via the exchange, and the quality measurement section receives the no-communication signal and indicates a predetermined no-communication state. The error rate of the communication line under test is measured by comparing it with the signal, and when the detection unit detects a calling signal from either the terminal device or the exchange side, the line measurement by the quality measurement unit is interrupted. This is achieved by a line quality monitoring system characterized by:

An embodiment of the present invention will be described above with reference to FIG. FIG. 2 is a diagram of a line quality monitoring system in a data exchange network according to an embodiment of the present invention. In FIG. 2, 1 is a terminal device, 2 is a subscriber line termination device, 3 is a subscriber line as a communication line, 4 is a data exchange, 41 is a detection unit that detects call origination and termination of the terminal device 1; Reference numeral 42 represents an exchange section for connecting the subscriber lines 3, and 5 represents a quality measurement section. If the terminal device 1 is currently in a non-communication state, it transmits a signal indicating the non-communication state to the data exchange 4 via the subscriber line 3. The formation of this signal is, for example, based on CCITT Recommendation
21, it is composed of 8 bits as shown in FIG. A detection unit 41 in the data exchange 4 constantly monitors the communication state of the accommodated subscriber line 3, and activates the quality measurement unit 5 when it detects a signal indicating a non-communication state as shown in FIG. The quality measurement unit 5 receives the signal transmitted on the subscriber line 3 and compares it with the signal format indicating a normal no-communication state as shown in FIG. 3, thereby determining the error rate of the subscriber line 3 to be measured. Measure.
When the terminal device 1 in a non-communication state requests a call and sends a call signal via the subscriber line 3, the detection unit 41 of the data exchange 4, which constantly monitors the subscriber line 3, detects the call signal. is detected, and immediately instructs the quality measuring section to suspend measurement of the error rate for the subscriber line 3, and at the same time instructs the switching section 42 to perform the switching connection requested by the call. Even during communication, the detection unit 41 of the data exchange 4 continues to monitor the subscriber line, and when disconnection of the subscriber line 3 is detected, it gives instructions to the quality measurement unit 5 again and measures the error rate in the same process as described above. Resume measurement. Furthermore, when a call arrives at a subscriber line 3 that is in a non-communication state, the data exchange 4 instructs the quality measuring section to suspend measurement of the error rate for the subscriber line 3, and performs a predetermined switching operation.

As is clear from the above description, according to the present embodiment, the transmission quality of the data exchange network N is constantly measured and monitored while providing communication services to subscribers, so that the transmission quality is determined by statistical processing of the measurement results. Trends in quality deterioration can be grasped in advance. In addition, since measurement and monitoring of transmission quality is carried out for each individual subscriber including the subscriber line 3, it is useful for preventive maintenance against overall transmission quality deterioration in communication services provided by the data exchange network N to accommodated terminal equipment. .

Note that FIGS. 2 and 3 are only one embodiment of the present invention, and the effects of the present invention will not change even if a signal format other than that shown in FIG. do not have. Furthermore, the terminal device 1 is not limited to the case where it is directly accommodated in the data exchange 4 via the subscriber line 3, but also when it is accommodated in the data exchange 4 after converging through a line concentrator, for example, some of the terminal devices in the line concentrator may By providing a fixed connection path and connecting the subscriber to be measured to the quality measurement section 5 via the connection path, the effects of the present invention are not impaired. Furthermore, the type of communication network is not limited to a data exchange network.

As described above, according to the present invention, the transmission quality of the communication path provided by the communication network to the subscribers can be comprehensively grasped at all times without impairing the communication service to the subscribers, and the level of the transmission quality can be maintained. It is possible to realize an effective line quality monitoring method.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an example of a conventional intra-network transmission quality measurement method in a data exchange network, Fig. 2 is a diagram of a line quality monitoring method in a data exchange network according to an embodiment of the present invention, and Fig. 3 is a diagram showing a state of no communication. FIG. In the figure, N...Data exchange network, L...Communication line, M...Error rate measuring device, 1...Terminal device, 2
...Subscriber line termination device, 3...Subscriber line, 4
...data exchanger, 41...detection section, 42...exchange section, 5...quality measurement section.

Claims (1)

[Claims] 1. In a communication network in which terminal devices are housed in a switchboard via a communication line, the switchboard is equipped with a detection unit and a quality measurement unit that detect call origination and termination on the communication line. When the detection unit detects the signal, the quality measurement unit is connected to the communication line in the no-communication state via the exchange, and the quality measurement unit receives the no-communication signal and converts it into a signal indicating a predetermined no-communication state. When the detection unit detects a calling signal from either the terminal device or the exchange side, the error rate of the communication line under test is measured.
A line quality monitoring method characterized in that line measurement by a quality measurement unit is interrupted.