JPH06338938A - Line abnormality reporting method - Google Patents

Abstract

PURPOSE:To always relay optional data string by transmitting an alarm signal obtained by setting a specified bit pattern to the frame bit of a multi frame signal by way of a sending means. CONSTITUTION:When a line interface part A in an exchange 1 receives an alarm signal, the exchange 1 regulates originating to an ISDN initiary group speed dedicated line 2 to be exchange connection between extension terminals within the present exchange. Thus, when line abnormality (abnormal part P) is generated on a ISDN initiary group speed dedicated line 4, a relay exchange 3 sends the alarm signal to the exchange 1 by way of an (m)-bit access part so that the normal time and the abnormal time of the line can be discriminated without a pattern for each relay data and the optional data string can always be relayed without limiting the pattern of the relay data string when the line is normal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a line abnormality notifying method in a relay exchange for relaying and exchanging transmission data from exchanges, multimedia multiplexers and the like.

[0002]

2. Description of the Related Art FIG. 3 shows a network system configuration diagram in which exchange groups are interconnected by an ISDN primary group speed dedicated line. In FIG. 3, the exchange 1 is connected to the transit exchange 3 through the ISDN primary group speed dedicated line 2.
The relay exchange 3 is connected to the exchange 5 via the ISDN primary group speed dedicated line 4. The exchanges 1 and 5 are provided with line interface units A and B having ISDN primary rate interfaces, respectively, and the repeater exchange 3 is provided with line interface units C and D having ISDN primary rate interfaces. Terminals 6 and 7 are connected to the exchange 1, and terminals 8 and 9 are connected to the exchange 5. Circuit switching and packet switching are performed between the terminals 6, 7, 8 and 9 by the respective switching systems 1 and 5 and the transit switching system 3.

FIG. 4 shows ISDN primary group speed dedicated lines 2 and 4.
FIG. 3 shows a frame structure diagram of a data signal in the above primary rate interface.

FIG. 5 shows an allocation diagram of frame bits (hereinafter referred to as F bits) in a multi-frame structure composed of 24 frames. In FIG. 5, a 6-bit frame synchronization pattern (00101) is included in each F bit of the 4th, 8th, 12th, 16th, 20th, and 24th frames.
1) is assigned, m bits for maintenance information are assigned to each F bit of the odd-numbered frame, and 2nd, 6th, 1st
6-bit CRC bits e1 to e6 used for error checking on the receiving side are assigned to the F bits of the 0th, 14th, 18th, and 22nd frames.

FIG. 6 shows a block diagram of a conventional line interface unit. It should be noted that, corresponding to C or D in FIG. 3, c or d is attached to the number of each constituent circuit section for distinction, and if there is no particular need to distinguish between C and D, it is not attached. In FIG. 6, the line interface unit 20 includes a frame assembling / disassembling unit 21 and a line abnormality detecting unit 2.
2, a unit control unit 23, an internal data bus interface unit 24, an alarm signal transmitting / receiving unit 25, and an m-bit access unit 26, and the frame assembling / disassembling unit 2
1 is connected to the ISDN primary group speed dedicated line 2, or 4, the unit controller 23 is connected to the central controller (not shown) by the internal control bus 27, and the internal data bus interface unit 25 is the internal data bus. It is connected by 28 to a time division time slot exchange section (not shown in particular). A frame assembling / disassembling unit 21 assembles and disassembles a frame of a data signal on the ISDN primary group speed dedicated line 2, or 4. The unit control section 23 controls the entire line interface section 20 and communicates with a central control section (not shown) inside the exchange. The alarm signal transmission / reception unit 25 outputs an alarm signal via the internal data bus interface unit 24 when the line is abnormal. During normal operation of the ISDN primary group speed dedicated line, the m-bit access unit 26 repeatedly sends a flag pattern (01111110) consisting of 8 bits to m bits at all times.

FIG. 7 shows a conventional alarm signal transmission flow chart. The conventional line abnormality notification method will be described below.

In the network system shown in FIG. 3, the ISDN primary group speed dedicated line 5 between the transit exchange 3 and the exchange 5 is out of synchronization, a line abnormality such as a line interruption occurs at the abnormal point P, and the line interface unit When the frame assembling / disassembling unit 21d in D detects an abnormality via the line abnormality detecting unit 28, an alarm signal is sent to the unit control unit 22d by the alarm signal transmitting / receiving unit 24d in the line interface unit 20d according to the TTC standard. Central control unit (in particular, via the internal control bus 26d
(Not shown). When the central control unit transmits the alarm signal to the line interface unit 20c, the line interface unit 20c sends the alarm signal to the ISD.
It is transmitted to the exchange 1 through the N primary group speed dedicated line 2.

As shown in FIG. 7, when the flag pattern (01111110) is repeatedly transmitted from the line interface section 22c of the repeater exchange 3 to m bits of the multiframe signal on the ISDN primary group speed leased line 2 (step s1). ), When an abnormality occurs on the ISDN primary group speed dedicated line 4, all bits of the information channels Ch1 to Ch24 which are data signals other than the frame bits of the multi-frame signal on the ISDN primary group speed dedicated line 2 are set to "1". Then, the exchange 1 is notified of the above line abnormality. When the alarm signal is received by the alarm signal transmitting / receiving unit 26a in the line interface unit A of the exchange 1, the exchange 1 sends only the ISDN primary group speed dedicated line 2 to the exchange connection between the extension terminals in the own exchange 1. Regulate.

As described above, also in the conventional exchange system, when an abnormality occurs on one of the relay destination ISD primary group speed leased lines of the relay exchange, the relay is relayed to the exchanges connected to other normal leased lines. It is possible to notify the previous line abnormality.

[0010]

However, in the above-mentioned conventional repeater exchange, when the line abnormality occurs on one relay destination ISD primary group speed dedicated line 4, the frame bit is transmitted to the other exchange 1 which is normally operating. Since a signal in which all bits of the information channels Ch1 to Ch24 which are data signals other than "1" are transmitted as an alarm signal, it is impossible to distinguish between the signal transmitted during normal operation and the alarm signal. That is, it becomes impossible to relay a data string in which all the data signals between the terminals exchange-connected by the repeater exchange are "1", that is, all the bits of the information channels Ch1 to Ch24 are "1" during normal operation. .

The present invention solves such a conventional problem, and a digital line relay capable of relaying an alarm signal indicating a line abnormality without restricting the pattern of a relay data string when the line is normal. It is an object of the present invention to provide a method of notifying a line abnormality in an exchange.

[0012]

In order to achieve the above object, a line abnormality notifying method according to the present invention comprises a plurality of exchanges and an IS.
In a network composed of transit exchanges connecting the plurality of exchanges to each other by a DN primary group speed dedicated line, line abnormality detecting means for detecting a line fault on the ISDN primary group speed dedicated line in the transit exchange, The line abnormality detection signal from the line abnormality detection means causes the I
By providing an alarm signal sending means for sending an alarm signal in which a specific bit pattern is set to the frame bit of the multi-frame signal forming the transmission data on the SDN primary group speed dedicated line, the line abnormality is detected by the line abnormality detecting means. When it occurs, the alarm signal is sent out by setting a specific bit pattern in the frame bit of the multi-frame signal forming the transmission data to all the exchanges connected to the transit exchange by the normal ISDN primary rate dedicated line. It is characterized in that it is transmitted via means.

[0013]

As described above, the line abnormality notification method of the present invention is
When an error occurs on one leased line in the repeater exchange, an alarm signal is sent to the other normal exchange by the frame header separately from the information channel, so there is a restriction on the pattern of the relay data string during normal operation. Never add.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

A network system to which an embodiment of the present invention is applied is assumed to have the same system configuration as that shown in FIG.

FIG. 1 shows an exchange according to an embodiment of the present invention,
Alternatively, a block diagram showing the configuration of the line interface unit provided in the transit exchange is shown.

In FIG. 1, the line interface unit 10
Is a frame assembling / disassembling unit 11, a line abnormality detecting unit 12, a unit controlling unit 13, an internal data bus interface unit 1.
4, alarm signal transmitting / receiving unit 15, m-bit access unit 1
6 and the frame assembling / disassembling unit 11 is I
The SDN primary group speed dedicated line 2, or 4 is connected, the unit controller 13 is connected to the internal control bus 17, and the internal data bus interface unit 18 is connected to the internal data bus 18.
It is connected to the.

FIG. 2 shows a flow chart of the alarm signal transmission of the line interface section. The frame structure of the ISDN primary group speed dedicated line 2 or 4 connected to the line interface unit 10 and the allocation of F bits in a multi-frame signal composed of 24 frames are the same as those in the conventional example. , And as shown in FIG.

The frame assembling / disassembling unit 11 assembles and disassembles the frame signal of the ISDN primary group speed dedicated line 2 or 4 and also makes the ISDN primary group speed dedicated line 2 or 4.
Alternatively, a line abnormality detector 12 for detecting line abnormality 4 is provided. The unit controller 13 controls the entire line interface 10 and communicates with a central controller (not shown) inside the exchange. The internal data bus interface unit 14 controls the information channels Ch1 to Ch on the ISDN primary group speed dedicated line 2, or 4.
24 is connected to the internal data bus 18 of the exchange. The alarm signal transmitting / receiving unit 15 sends an alarm signal when the frame assembling / disassembling unit 11 detects a line abnormality. m-bit access unit 16
In the normal operation of the line, the flag pattern (01111110) consisting of 8 bits is repeatedly transmitted to the m bits.

Next, the operation of notification of a line abnormality in the repeater exchange according to the embodiment of the present invention will be described with reference to FIGS. 1, 2, 3 and 4.

It is assumed that the line interface unit 10 is applied to the transit exchanges C and D in the network configuration diagram shown in FIG. It should be noted that the numbers of the respective constituent circuit parts corresponding to C or D in FIG.
Or, if it is not necessary to distinguish D, it shall not be attached.

As shown in the alarm signal transmission flow chart of FIG. 2, when no line abnormality occurs in the ISDN primary group speed dedicated line 4 and no abnormality occurs in the transmission data, the m-bit access unit 16 transmits a multi-frame frame A flag pattern (01111110) consisting of 8 bits is always transmitted on m bits which are bits (step S11). At this time, if there is a loss of synchronization on the ISDN primary group speed dedicated line 4 between the repeater exchange 3 and the exchange 5, or an abnormality (abnormal point P) occurs due to disconnection of the line, etc., the line interface unit 10d of the repeater exchange 3 A line abnormality is detected by the frame assembling / disassembling unit 11d (step S12). When the line abnormality is detected, the alarm signal transmission / reception unit 15d in the line interface unit 10d sends a message to the relay destination exchange 1 via the m-bit access unit 16d to the normal ISDN primary group speed dedicated line 2
An alarm signal with all bits set to "1" is transmitted (step S13). As a result, the exchange 1 is notified that an abnormality has occurred on the ISDN primary group speed dedicated line 4.

When the line interface section A in the exchange 1 receives the alarm signal, the exchange 1 restricts the transmission to the ISDN primary group speed dedicated line 2 and restricts the exchange connection between the extension terminals in the own exchange. .

Thus, according to the above embodiment, the ISD
When a line abnormality (abnormal point P) occurs on the N primary group speed dedicated line 4, from the relay exchange 3 to the exchange 1,
Since the alarm signal is sent out through the m-bit access unit 16, whether the line is normal or abnormal can be discriminated irrespective of the pattern of the relay data string, and there is no restriction on the pattern of the relay data string when the line is normal. , Any data string can be relayed at any time.

[0025]

As is apparent from the above embodiment, the present invention makes it possible for the transit exchange to have a normal ISDN primary group speed even when an abnormality occurs on the ISDN primary group speed leased line connecting the exchange and the transit exchange. Since an alarm signal is sent to all the exchanges connected by a dedicated line via the m bits of the frame header, it is possible to distinguish whether the line is normal or abnormal regardless of the pattern of the relay data string. An arbitrary data string can always be relayed without any restriction on the pattern of the relay data string at the time of relaying.

[Brief description of drawings]

FIG. 1 is a configuration block diagram of a line interface unit provided in an exchange or a transit exchange according to an embodiment of the present invention.

FIG. 2 is a flow chart of an alarm signal transmission of a line interface unit in the above embodiment.

FIG. 3 is a network system configuration diagram for interconnecting exchange groups by an ISDN primary group speed dedicated line.

FIG. 4 is a frame configuration diagram of a data signal in a primary rate interface on an ISDN primary rate dedicated line.

Fig. 5 Allocation diagram of frame bits in multi-frame configuration

FIG. 6 is a configuration block diagram of a conventional line interface unit.

FIG. 7 is a conventional alarm signal transmission flow chart.

[Explanation of symbols]

 1,5 Switch 2,4 ISDN primary group speed dedicated line 3 Relay switch 6,7,8,9 Terminal 10 Line interface unit 11 Frame assembly / disassembly unit 12 Line error detection unit 13 Unit control unit 14 Internal data bus interface unit 15 Alarm signal transmission / reception section 16 m-bit access section 17 Internal control bus 18 Internal data bus

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Claims (1)

[Claims] 1. A method of notifying a line abnormality in a network comprising a plurality of exchanges and a transit exchange that interconnects the plurality of exchanges by an ISDN primary group speed leased line, wherein the ISDN primary is provided in the transit exchange. A line abnormality detecting means for detecting a line failure on the group speed dedicated line, and a frame bit of a multi-frame signal forming transmission data on the ISDN primary group speed dedicated line by the line abnormality detection signal from the line abnormality detecting means. By providing an alarm signal transmitting means for transmitting an alarm signal in which a specific bit pattern is set, a normal ISDN is provided when a line abnormality is generated by the line abnormality detecting means.
Transmitting an alarm signal having a specific bit pattern set to a frame bit of a multi-frame signal forming the transmission data to all the exchanges connected to the transit exchange by a primary group speed dedicated line via the alarm signal transmitting means. A method of notifying a line abnormality characterized by.