JP2003224625A - Line switching connection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a line switching connection device which automatically switches a line in case of line trouble without hinder a CTI system from operating. <P>SOLUTION: In case of no response to a specified message from an INS network within a specified time, line trouble is detected and the line is switched and connected. In the line switching, the switching is judged by judging the state of other logical lines included in the same physical line. Further, the switching of the line is judged while a cumulative frequency of trouble occurrence to logical lines included in the same physical line is taken into consideration. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a CTI (Computer
ISDN used in Telephony Integration system
The present invention relates to a line switching connection device that detects a line fault and automatically switches the fault line to a normal line.

[0002]

2. Description of the Related Art A CTI (Computer Telephony Integratio) in which a computer and a telephone are linked, as represented by a system example of a so-called telephone call center, which receives various kinds of information from a database in response to a call from a customer.
n) (hereinafter, simply referred to as "CTI") system is widely used. Also, with the rapid expansion of the INS network in recent years, the number of systems using the INS network is increasing in the CTI system. In such a CTI system, a computer telephony server (hereinafter simply referred to as "CTS") of a CTI provider is connected to an INS network through an ISDN line (hereinafter simply referred to as "line"). Become.

In such a CTI system, it is necessary to always accept inquiries from customers. For this reason,
Generally, a CTI operator has two systems, a working system and a standby system, and adopts a configuration in which when a failure occurs in the working line, the line to be used is switched to the protection line and the spare CTS is connected to the INS network. There is. Here, the state of line switching in the conventional CTI system will be described with reference to FIG.

In FIG. 1, (10) is an INS network, (20) is a line switching connection device, (30) is a working CTS, and (40) is a spare C.
TS, (50) represents a spare terminal adapter, and (60) represents a plurality of extension telephones. As shown in the figure, the line switching connection device (20) is located between the INS network (10) and the working CTS (30) and the backup CTS (40).
0) is connected to the working CTS (30) via the main route line. In addition, there are multiple extension telephones at the end of each CTS.
(60) is connected, and a large number of operators respond to inquiries from customers through their respective telephones. Figure 1
If any failure occurs in the main route line in this system, the system administrator recognizes this and switches the line switching connection device (20) by manual operation, and the INS network (10)
Is connected to the spare CTS (40) via a normal subroute line.

However, in the conventional line switching / connecting device, the system administrator judges the occurrence of a line failure and switches the line manually, so that a lot of times are taken until the line fails and the working line is switched to the backup line. Needed time. On the other hand, in order to realize such an automatic line switching, it was necessary to solve the following judgmental problems in line switching. (1) Line failure judgment A line failure must be judged by monitoring data communication from both the INS network and the CTS. Further, the data communication between the INS network and the CTS should not be hindered by the failure of the line switching connection device itself. Further, the line switching connection device must synchronize with the data communication between the INS network and the CTS so as not to affect the data communication. Therefore, in order to realize automatic line switching, it is necessary to interpret the messages from both the INS network and the CTS in synchronization with the data communication to judge the line failure. (2) Judgment of line switching The basic speed interface (Basic Rat
e Interface) (hereinafter simply referred to as “BRI”) line and Primary Rate Interface (Primary Rate Interfac
e) There is a line (hereinafter, simply referred to as “PRI”), and each physical line accommodates a plurality of logical lines (channels). By the way, B channel (64k
2 channels of bit / s) and 1 channel of D channel (16 kbit / s) are accommodated. For example, the PRI line has 23 channels of B channel (64 kbit / s) and 1 channel of D channel (64 kbit / s). The channel is housed. Therefore, even if a failure occurs in one logical line, it is necessary to make a decision to switch the physical lines so as not to affect other channels in the same physical line. (3) Judgment of processing when power is restored In general, the line switching connection device (20) of the CTI system has a backup CTS (4
0) is forcibly connected. This is to back up the use of the telephone only with a spare terminal adapter (50) that can be operated by batteries. Therefore, if the main route line is simply switched to when the power is restored (hereinafter, simply referred to as "power restoration"), the call made through the sub route line may be disconnected. For this reason, it was necessary to judge the use of each line before switching lines when power was restored.

[0006]

SUMMARY OF THE INVENTION The present invention is to solve such a problem, and detects a line failure accurately and quickly to automatically switch the line, and does not hinder the operation of the CTI system. An object is to provide a connection device.

[0007]

SUMMARY OF THE INVENTION The present invention is a line switching connection device for selectively connecting a working line connected to a working terminal and a protection line connected to a protection terminal to an INS network. A line switching circuit that disconnects the working line from the INS network and connects the protection line to the INS network according to a control signal, and a terminal side from a terminal side within a predetermined time for a specific message from the INS network. A message monitor circuit that detects that no response message is generated and generates a no-response detection signal, and a control circuit that determines a line failure based on the no-response detection signal and generates the switching control signal. It is characterized by including.

[0008]

2 is a block diagram showing a first embodiment of a line switching / connecting device according to the present invention. In the figure, the line switching connection device (20) is an INS network (10) and an active C.
It is located between TS (30) and spare CTS (40),
Normally, the working C is connected to the INS network (10) via the main route line.
It is connected to TS (30).

The line switching connection device (20) is based on information from the switch unit (21) that actually switches the line, the monitor unit (22) that monitors communication data on the line, and the monitor unit (22). The control unit (23) for controlling the switching process of the switch unit (21)
It consists of The monitor section (22) is an INS network (10).
And interpret the data in synchronization with the data communication performed between the working CTS (30). In addition, CT in FIG.
Since the configuration of the I system itself is the same as that of the conventional example shown in FIG. 1, the CTS (30) and (4
Descriptions such as 0) are omitted.

Next, the line switching connection device (20) of this embodiment
The details of the processing operation in step 1 will be described below. First, IN
A subroutine of the fault detection process in the layer 2 of the S network (10) and the working CTS (30) will be described with reference to the flowchart shown in FIG. By the way, layer 2 means OSI (Open
Systems Interconnection) It is based on the data link protocol in the second layer of the basic reference model.
It defines a communication processing procedure for transmitting a message between terminals in an NS network in an appropriate data transfer unit without error.

In the subroutine shown in FIG. 3, the control unit (23) sends a message from the INS network (10) via the monitor unit (22) as an extended asynchronous balanced mode setting (hereinafter simply referred to as "SABME") related to the setting of the data link. It is activated by detecting the reception of a signal called "". As a result, the control unit (23) starts the line failure detection process.
Start a timer with a predetermined length of time (step 1
0) Go to next step 11.

In step 11, the control unit (23) monitors the message from the working CTS (30) via the monitor unit (22) and confirms the unnumbered Ackn from the CTS.
owledg) (hereinafter, simply referred to as "UA") signal is determined. In the layer 2 communication procedure, the terminal connected to the INS network must always return the message of the UA signal to the SABME signal which is the message from the INS network. Therefore, if there is a response from the working CTS (30) to the UA signal within a predetermined time from the detection of the SABME signal from the INS network, the control section (23) judges that the line is normal and the step 12 Then, the line failure detection process ends.

On the other hand, in step 11, the working CTS
When the UA signal is not detected in the message from (30), the control section (23) moves to step 13 and determines whether or not the timer started in step 10 has ended. If it is determined that the timer has not expired, it means that the allowable time for detection of the response message from the CTS has not yet elapsed, so the control unit (23) proceeds to step 15. , So-called "waiting state"
The WAIT process is started.

In the WAIT process, the control unit (23)
Returns to step 11 at a predetermined timing while performing processing other than this subroutine, and returns to the working CTS (30) described above.
Repeat the process of monitoring the message from and determining the message.
When it is determined in step 13 that the timer started in step 10 has expired, it means that there is no response of the UA signal from the working CTS (30) within the predetermined time set by the timer. The department (23) judges that there is a failure in the main route line (step 14).
This subroutine ends.

Next, the subroutine of the fault detection processing in layer 3 will be described with reference to the flow chart shown in FIG. By the way, layer 3 means OSI (Open Systems In
terconnection) This is based on the protocol in the third layer of the basic reference model, and defines the procedure such as call setting processing between terminals of the INS network. In the subroutine shown in FIG. 4, the control unit (23) uses the monitor unit (22) to input I
As a message from the NS network (10), call setup (Set Up)
It is activated by detecting reception of a signal (hereinafter, simply referred to as "SETUP").

As a result, the control unit (23) activates a timer having a predetermined time length to start the line failure detection process (step 20) and shifts to the next step. In the next step 21, the control unit (23) determines again whether or not the SETUP signal has been received as a message from the INS network (10). If a SETUP signal is received, I
Since the call setting process has been retried from the NS network 10, the control unit 23 returns to step 20 and restarts the timer.

On the other hand, when the SETUP signal is not received as a message from the INS network (10), step 2
Proceed to 2 and disconnect the call as a message from the INS network (10).
It is determined whether or not a (Disconnected) (hereinafter, simply referred to as "DISC") signal is received. When the DISC signal is received, the communication link between the INS network (10) and the working CTS (30) is released, and it is no longer necessary to detect the line failure. Therefore, the control unit (23) proceeds to step 23 and determines that the line is normal and terminates the failure detection process.

On the other hand, in step 22, the INS network (1
When it is determined that the DISC signal has not been received as the message from (0), the control unit (23) proceeds to step 24.
Then, this time, as a message from the working CTS (30), a call setup process (Call Proceeding) (hereinafter, simply "C
Signal called ALL PROC ”, call connection (Connect)
(Hereinafter, simply referred to as “CONN”) signal, connection release completion (Release Complete) (hereinafter, simply referred to as “REL COM
P ") signal or a DISC signal is received.

At the layer 3, the working CTS (3) that has received the SETUP signal as a message from the INS network (10)
0) always IN any of the above messages within a predetermined time
It must be returned to the S network (10). Therefore, the control unit (2
If any of the above signals is detected in the message from the working CTS (30), 3) judges that the line is normal and proceeds to step 23 to end this subroutine.

On the other hand, in step 24, the working CTS
When none of the above signals is detected as the message from (30), the control section (23) moves to step 25 and determines whether or not the timer started in step 20 has expired. When it is determined that the timer has not expired, the process proceeds to step 27, and the so-called "waiting state" WAIT processing is started.

In such WAIT processing, the control unit (23)
Performs processing other than this subroutine, returns to step 21 of this subroutine at a predetermined timing, and repeats monitoring of the message from the working CTS (30) and determination of its contents. When it is determined in step 25 that the timer started in step 20 has expired, the working CTS (3
Since there is no response of the predetermined signal from 0), the control section (23) judges that there is a failure in the line (step 26) and terminates this subroutine.

In the layer 2 and layer 3 subroutines described above, when it is determined that a failure has occurred in the main route route for use, the control section (23) controls the switch section (21). Switch the line in use from the main route line currently in use to the spare sub route line. By this process, the backup CTS (40) is transferred to the I
Connected to the NS network (10), CTI operations will continue without delay.

Next, a second embodiment of the line switching connection device according to the present invention will be described. Since the configuration of the line switching connection device according to this embodiment is similar to that of the first embodiment described above, the description of the components of such device will be omitted. By the way, for ISDN line, as described above,
There are two types of lines, RI lines and PRI lines, and each one physical line accommodates a plurality of logical channels. Therefore, when a failure occurs in one channel, the line switching connection device needs to make a switching judgment of the physical line so as not to affect other channels included in the same physical line. It can be said that the present embodiment adds the determination function according to the first embodiment.

In the second embodiment, first, the operation subroutine for switching the BRI line will be described with reference to the flowchart of FIG. Based on the above-described first embodiment, it is assumed that the subroutine shown in FIG. 5 is activated when a failure is detected in, for example, the B1 channel of the two logical lines B1 or B2 included in the BRI line. However,
The present embodiment is not limited to such a configuration, and may have a configuration of a subroutine that is activated by detecting a failure of the B2 channel, for example.

When the same subroutine is started, the control unit (2
3) First, in step 30, the state of the B2 channel is confirmed and judged. Then, if the same channel is not busy, the process proceeds to step 35, where the switch unit (21) is instructed to switch the line and the present subroutine is terminated. On the other hand, if the state of the B2 channel is busy, the process moves to step 31 and enters the so-called WAIT state. In this state, the control unit
In (23), the processing of this subroutine is temporarily suspended, other processing is executed, and control is returned to this subroutine again at a predetermined timing. When the process returns from the WAIT state to this subroutine, the control unit (23) again checks the state of the B2 channel in step 32.

If the call on the B2 channel has ended, it is judged in the following step 34 whether or not the failure of the B1 channel continues. If the failure has not been recovered yet, the operation moves to step 35 to switch the line. Go to and end this subroutine. On the other hand, in step 32, B
When it is determined that the two channels are still in a call, the control unit (23) moves to step 33, determines whether or not the failure of the B1 channel continues, and if the failure is not yet recovered, the step 31 Return to the WAIT state and repeat the above processing again.

On the other hand, step 33 and step 3 described above.
When it is determined in step 4 that the failure of the B1 channel has been recovered, the control unit (23) moves to step 36 and B1
This clears all fault information related to the channel, terminates this subroutine without performing the switching process because the line is normal. As described above, according to this embodiment, after detecting a failure in one channel of the BRI line, the line is switched after confirming the state of the other channel included in the same line. It is possible to switch lines without causing a call disconnection. Also, if the fault is recovered while waiting for the line switching during a call, the line is not switched. As a result, the operation of CTI can be prevented from being interrupted as much as possible.

Next, the processing for switching the PRI line in the second embodiment of the present invention will be described. As described above, the PRI line includes, for example, 23 logical lines (channels) in one physical line. Therefore,
If a switching control method for detecting a failure in all channels and switching lines is adopted, the operation will be performed in a state where the CTI function is deteriorated. For example, assuming that a failure has occurred in 20 out of 23 channels included in the PRI line, the line is not switched even in such a state, and the operation is continued only in the remaining 3 channels of the main route line. It will be. Then, the service cannot be received on the four channels and after.

Therefore, when switching the PRI line,
The processing is performed based on the subroutine shown in the flowchart of FIG. When a failure is detected in any one of the logical lines (channels) B1 to B23 included in the PRI line according to the first embodiment described above, the subroutine shown in FIG. 6A is started. It

In the same subroutine, the control unit (23) first sets the fault register of the Bx channel in step 40. Here, the fault register is a storage means provided for each channel included in the PRI, and is set to "1" when a fault of the corresponding channel is detected. In the next step 41, the control unit (23) increments the value n of the failure counter, that is, (n + 1) → (n), and proceeds to step 42. Here, the failure counter represents a counter that is incremented every time the failure register of any channel is set.

In the following step 42, the control unit (23)
Compares the count value n of the fault counter with a predetermined threshold value N. Here, the threshold value N is assumed to be a predetermined value at the time of system design of CTI so that the line is switched to the sub-route which is the protection line when a failure included in the channel included in the PRI line is detected N times or more. When n has reached N in step 42, the control unit (23) moves to step 43, determines that a failure has occurred in the main route line for the current operation, and switches the line to the switch unit (21). Is issued to end this subroutine.

On the other hand, if n has not reached N in step 42, the control section (23) moves to step 44 and WAI.
Enter the T state. When the process returns from the WAIT state to this subroutine at a predetermined timing, the control section (23) checks the state of the fault registers of all the channels included in the PRI line in step 45. Then, if the fault registers of all the channels are reset, it is determined that the line is normal, and this subroutine is terminated without performing the switching process (step 47).

On the other hand, when the set fault register remains, the control unit (23) returns to step 44 and repeats the above-mentioned processing. When the PRI line is switched, the subroutine at the time of failure recovery shown in the flowchart of FIG. 6B is operated in parallel with the subroutine at the time of failure occurrence of FIG. 6A.

The subroutine shown in FIG. 6 (B) is activated by detecting the failure recovery of the Bx channel included in the PRI line. In the same subroutine, the control unit
In step (23), first, the fault register corresponding to the Bx channel whose fault has been restored in step 50 is reset to "0".
Then, in the following step 51, the value of the failure counter n described above is cleared, that is, (n = 0), and this subroutine is ended.

As described above, P based on this embodiment
According to the RI line switching process, the line is switched when a failure in the logical line (channel) is detected continuously for a predetermined number of times or more, so that the system operation is performed while preventing the deterioration of the CTI service function as much as possible. You can Next, a third embodiment of the line switching connection device according to the present invention will be described. FIG. 7 is a block diagram showing the configuration of the line switching connection device according to the present embodiment.

In the line switching connection device (20) shown in the figure, the condition setting unit (24) is a data input unit such as a keyboard or a switch panel for presetting a switching route at the time of power recovery. is there. As described above, in the line switching connection device (20) of the general CTI system, the backup CTS (40) is connected via the sub-route line in the case of system power failure.
Are connected to the INS network. For this reason, it is necessary to determine whether to switch the line when power is restored, whether to maintain the spare subroute or switch to the working main route.

Therefore, in the embodiment shown in FIG. 7, it is assumed that the condition setting section (24) is used to previously set a switching route at the time of power recovery. Further, such condition setting may be variable according to the operating hours of the system, for example. By adopting such a configuration, it is possible to prevent troubles at power recovery. For example, when an unattended service is performed at night in an active system, it is necessary to continue such service even after power restoration. In this case, it suffices to use the condition setting section (24) to set the switching to the working line side of the main route when the power is restored. In addition, if a power failure occurs during the daytime, it is highly possible that an operator stationed in the backup system will provide service by telephone. Therefore, in this case, if the backup line of the sub-route is set to be maintained when the power is restored, it is possible to prevent the operator from disconnecting the call after the power is restored.

In the embodiment shown in FIG. 7, all the other constituent elements in the system are the same as those in the first and second embodiments described above, and the description thereof will be omitted. In the first to third embodiments described above in detail, the case where the CTS of the backup system is connected to the subroute which is the backup line has been described as an example, but the present invention is not limited to such cases. Not something. For example, a service such as representative subscription may be registered in advance without connecting the backup system to the subroute. In this case, when a failure occurs in the current main route and the line is switched to the sub route, the INS network detects no response from the sub route, and automatically makes a call for customer customization by other representative subscription. Since it is connected to the line, the service in the CTI system can be maintained.

Next, a fourth embodiment of the line switching connection device according to the present invention will be described. Incidentally, this embodiment relates to the operation after the line switching connection processing is performed. A failure occurs in the working CTS (30) or working line, and the line switching connection device (20) reserves the CTS for the INS network (10).
When switched to the side, messages may be exchanged as shown in the sequence chart of FIG. 8, for example.

That is, when the line connection is switched, IN
The S network (10) loses the working CTS (30) which has been the terminal of the INS network (10) until then due to a defect such as a momentary interruption of the synchronization signal. Therefore, the INS network (10) is RR (Recei
ve Ready) signal is transmitted a predetermined number of times to prompt a response from a terminal connected to the network (sequence S81). Working C
Assuming that the terminal identification number (TEI) of the TS (30) is "11", the INS network (10) recognizes the working CTS (30) as a terminal connected to the INS network immediately after switching the line connection. Therefore, the terminal identification number included in the RR signal is T
EI = 11. That is, at this point, the backup CTS (4
0) and the INS network (10) are not synchronized, and the backup C
The terminal identification number (TEI = 55) of TS (40) is the INS network (1
Not recognized by 0). In the sequence S81, the RR signal is transmitted from the INS network (10) four times.
The number of times the RR signal is retransmitted is not limited to this case.

Next, the INS network (10) uses the sequence S82.
At the working CTS (30), the SABME signal (TEI = 1)
1) is sent to prompt its initialization, but there is no response from the working CTS (30) because the line connection has already been switched.
Then, the monitor unit 22 in the line switching connection device (20)
In order to receive the SABME signal (TEI = 11) from the INS network (10), the above-mentioned subroutine of the fault detection processing in layer 2 shown in FIG. 3 is activated.

On the other hand, at the time when the sequence S82 has passed, the INS network (10) has the spare CT connected to the network because a certain amount of time has already passed since the line connection was switched.
SABME that has discovered S (40) and prompts it for initialization
A signal (TEI = 55) is transmitted (sequence S8)
3). Upon receipt of the SABME signal (TEI = 55), the line switching / connecting device (20) again activates the fault detection processing subroutine of FIG. However, since the backup CTS (40) receiving this signal immediately returns the UA signal (TEI = 55) to the INS network (10) (sequence S84), the failure detection processing subroutine is cleared as shown in the flowchart of FIG. To be done. afterwards,
The exchange using the message such as the RR signal (TEI = 55) is started between the INS network (10) and the backup CTS (40) (sequence S85).

On the other hand, the INS network (10) has the working CTS for a predetermined time until it gives up the link formation with the working CTS (30).
The SABME signal (TEI = 11) is continuously output to (30) (sequence S82 and sequence S86), whereby the failure detection processing subroutine of FIG. 3 continues to be activated. However, since the connection with the working CTS (30) has already been disconnected, the UA signal (TEI = 11) which is a response message to the above signal is not detected.
Therefore, the fault detection processing subroutine of FIG. 3 detects a line fault (sequence S87).

In order to prevent the above-mentioned problems, in this embodiment, as shown in the sequence chart of FIG. 9, for a predetermined time T1 immediately after the line switching connection device (20) performs the line switching connection. , The activation of the failure detection processing subroutine shown in FIG. 3 is stopped. By the way, time T1 is INS
When the network (10) is connected to the network, it is the time until giving up the access to the virtual terminal.

As a method of stopping the activation of the failure detection processing subroutine, for example, the line switching connection device (20)
The monitor unit (22) therein may be configured not to generate an interrupt signal to the control unit (23) even when receiving the SABME signal during the time T1. Alternatively, the operation of the failure detection processing sub-routine may be left unchanged, and the line switching control operation for the switch unit (21) may be held during the time T1 even if the control unit (23) detects a line failure. Further, a configuration in which these processes are combined may be adopted.

Since the present embodiment has the configuration as described above, for example, after switching the line connection due to the occurrence of a failure in the point-multipoint connection, the INS network (10) keeps the working C
Although the message is sent with the terminal identification number of TS (30), the spare CTS (40) connected by the sub-route can prevent the problem of erroneous detection of line failure by sending the message with the new terminal identification number. .

The hardware configuration of this embodiment is the same as that of the first to third embodiments described above, and the description thereof is omitted. Next, a fifth embodiment of the line switching connection device according to the present invention will be described. Incidentally, this embodiment, like the above-mentioned fourth embodiment, also relates to the operation after the line switching connection processing is performed.

Unlike the above-mentioned FIG. 8, when a failure occurs in the working CTS (30) or the working line and the line switching connection device (20) switches the INS network (10) to the spare CTS side,
For example, messages may be exchanged as shown in the sequence chart of FIG. That is, when the line connection is switched, the INS network (10) loses the working CTS (30) which has been the terminal of the INS network (10) until then due to a defect such as a momentary interruption of the synchronization signal. Therefore,
The INS network (10) sends an RR (Receive Ready) signal a predetermined number of times to prompt a response from a terminal connected to the network (sequence S101). Although the RR signal is transmitted four times from the INS network 10 in sequence S101, the number of times the RR signal is retransmitted is not limited to this case.

Next, the INS network (10) uses the sequence S10.
In step 2, the SABME signal is sent to the working CTS (30) to prompt its initialization, but there is no response from the working CTS (30) because the line connection has already been switched. Then, the monitor unit 22 in the line switching connection device (20) uses the INS network (10).
In order to receive the SABME signal from, the subroutine of the fault detection processing in layer 2 shown in FIG. 3 is activated.

On the other hand, after a certain amount of time has passed since the line connection was switched, synchronization is established between the INS network (10) and the backup CTS (40). Ten)
The SABME signal is sent to (sequence S103).
Then, as shown in sequence S104, the INS network (10)
And the spare CTS (40) continue to send SABME signals to each other, and in the line switching connection device (20) the S from the INS network (10)
Each time the ABME signal is detected, the failure detection processing subroutine is activated.

Further, after a predetermined time has passed, the INS network (1
0) gives up sending the SABME signal, and only the spare CTS (40) continues to send the SABME signal (sequence S10).
5) In the fault detection processing subroutine, since the UA signal which is the response message of the SABME signal cannot be detected, it is determined that the line fault has occurred (sequence S).
106).

In order to prevent the above-mentioned problems, the line switching / connecting device (20) in this embodiment performs the processing shown in the sequence chart of FIG. That is, immediately after the line switching connection is performed, the line switching connection device (20) keeps the INS network (10) and the backup CTS (40) for a predetermined time T1.
Both SABME signals are detected, and a failure detection processing subroutine is started.

By adopting such a configuration, even after the INS network (10) gives up sending the SABME signal in sequence S105, the failure detection processing subroutine is retriggered by the SABME signal from the spare CTS (40). Therefore, the failure detection processing subroutine shown in FIG. 3 does not time up and the failure of the line is not detected. Then, after a lapse of a predetermined time, as shown in sequence S107 of FIG.
By sending out the UA signal in response to the SABME signal from (40), the line is judged to be normal and the INS network (10)
The exchange of messages between the backup CTS (40) and the backup CTS (40) is started. Incidentally, the time T1 may be at least the time until the INS network (10) transmits the UA signal in response to the SABME signal from the backup CTS (40).

Since the present embodiment has the configuration as described above, for example, in the case of point-to-point connection, after switching the line connection due to the occurrence of a failure, the INS network (10) and the backup CTS
Both (40) continue to send SABME signal, and then IN
It is possible to prevent the problem that the line failure is erroneously detected due to the suspension of the SABME signal transmission from the S network (10).

The hardware configuration of this embodiment can be the same as that of the first to third embodiments described above, and the description thereof will be omitted. Next, a sixth embodiment of the line switching connection device according to the present invention will be described. Incidentally, in each of the embodiments described above, the INS network (1
Only the switching connection between 0) and the working CTS (30) or the spare CTS (40) was handled. However, this embodiment refers to a line switching connection system including switching connection between the working CTS (30) or the backup CTS (40) and extension terminal equipment such as a telephone.

First, an extension terminal device such as a telephone and an active C
FIG. 12 is a block diagram showing the configuration of a conventional line switching connection system including switching connection with the TS (30) or the backup CTS (40). In the figure, normally, the INS network (10) → line switching connection device (20) → working CTS (30) → extension switching connection device (7
0) → The system is operated by the so-called main route of the extension telephone (60). When a failure is detected in the working CTS (30) or working line, the INS network (10) → line switching connection device (20) → spare CTS (40) → extension switching connection device (70) → extension telephone ( The system operation is continued by the so-called sub route of 60). By the way, the extension switching connection device (7
0) is an extension telephone that is connected to the line switching connection device (20) by the switching cooperation control signal supplied to the device.
Extension terminal equipment such as (60) is spare CTS from working CTS (30)
It is for switching connection to (40).

In the following description, the side of the line switching / connecting device (20) is referred to as the "outside line side", and the line switching / connection process performed on the outside line side is referred to as the "outside line switching". The side of the extension switching / connecting device (70) is referred to as "extension side", and the switching connection processing of extension terminal devices performed on the extension side is referred to as "extension switching". By the way, in the conventional line switching connection system shown in FIG. 12, when the failure on the main route side is detected and the line is switched to the sub route side, the connection between the outside line and the extension side is constantly changed by the switching function of the CTS. . Therefore, although call protection on the outside line side (security of the connection link) is possible, there is a problem that call protection on the extension side is difficult. This will be specifically described based on the switching connection diagram of the outside line and the inside line shown in FIG.

That is, in the conventional line switching system,
When a fault is detected on the outside line side, the operation process is as follows. (1) For example, when a fault occurs in the outside line 3 shown in FIG. 13, the line switching connection device (20) on the outside line side, which detects it,
A switching cooperation control signal is sent to the extension switching device (70) on the extension side to instruct switching on the extension side. (2) After that, on the outside line side, the lines other than the one currently in communication, that is, the outside lines 3, 4, and 5 are blocked, and the completion of the conversation of the outside lines 1 and 2 currently in communication is waited. (3) On the other hand, on the extension side, all the extensions are transferred from the working CTS (30) to the backup CTS (40) in response to the above-mentioned switching cooperation control signal.
Switch to and connect. At this time, the calls of the extensions 1, 2, 4, 5 that are currently talking on the extension side are forcibly disconnected. (4) In the step (3) above, all the calls on the extension side are forcibly ended, and accordingly, the calls on the outside lines 1 and 2 are ended on the outside line side. The line switching connection device (20) waiting for this sends all outside lines to the working CTS (30).
To switch to the spare CTS (40).

That is, in the conventional line switching connection system, it is impossible to detect how the working and protection CTSs connect the outside line and the inside line. Therefore, the operation processing described above is performed, and the extension currently in communication is disconnected. In order to prevent such problems,
The present embodiment employs a line switching connection system configuration as shown in FIG.

In the figure, the extension switching connection device (70) is
A plurality of extension terminal devices such as telephones are switched and connected from the working CTS (30) to the backup CTS (40), and it also has a function of an extension exchange device that interconnects the extension terminal devices.
Further, the extension call monitoring unit (71) monitors the call state of the extension terminal device in the extension switching connection device (70), and switches the extension side switching connection of the extension switching connection device (70) according to the call state. It has the function of controlling the procedure. The other constituent elements of this embodiment are the same as those of the first embodiment shown in FIG.

Next, the operation of the switching connection processing in this embodiment will be described in steps (10) to (60) shown below. The operation will be described based on the external connection / extension switching connection diagram shown in FIG. (10) For example, when a failure occurs in the external line 3 shown in FIG. 13, the external line side line switching connection device (20) sends a switching cooperation control signal to the internal line side to instruct the internal line to switch the connection. (20) After that, on the outside line,
That is, the outside lines 3, 4, and 5 are blocked, and the outside lines 1 and 2 that are currently talking
Wait for the call to end. (30) On the other hand, on the extension side that has received the above-mentioned switching cooperation control signal, the extension call monitoring unit (71) detects the extension that is currently talking and notifies the extension switching connection device (70) of that information. The extension switching / connecting device (70) switches and connects the extension other than the one in communication, that is, the extension 3 from the working CTS (30) to the backup CTS (40). Then, it waits for the end of the call of the extensions 1, 2, 4, 5 currently in the call. (40) Thereafter, the extension call monitoring unit (71) constantly monitors the extension call state and notifies the extension switching / connecting device (70) each time the extension call ends. The extension switching device (70) switches and connects the extension from the working CTS (30) to the backup CTS (40) each time. (50) When the call on the extension side ends, naturally the call on the outside line connected to it also ends. Therefore, on the outside line side, the monitor unit (22) in the line switching connection device (20) detects the end of the call on each outside line and notifies the control unit (23) of this. The control unit (23) controls the switch unit (21) on the basis of the notification, and sequentially switches the outside lines after the call to the working C line.
Switch connection from TS (30) to spare CTS (40). (60) When the connection switching of all the extension lines and the outside lines that have been terminated is completed by the progress of the step (50), the line switching connection device (20) on the outside line switching side reserves all the outside lines in the blocked state for backup CTS. Switch to (40) and end processing.

As described above, according to the present embodiment, the extension side call connection device (70) performs call monitoring on the extension side,
From the extension where the call ends, the connection is switched sequentially.
Therefore, even if the working and protection CTSs do not know the mutual connection relationship between the external line and the internal line, it is possible to protect the call on both the internal line and the external line side.

[0063]

As described above in detail, according to the present invention, CT
It is possible to provide a line switching connection device that automatically switches lines in the event of a line failure without disturbing the operation of the I system.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of line switching in a conventional CTI system.

FIG. 2 is a block diagram showing the configuration of a line switching connection device according to the first embodiment of the present invention.

FIG. 3 is a diagram showing a flowchart of layer 2 fault detection processing in the embodiment of FIG. 2;

FIG. 4 is a diagram showing a flowchart of a layer 3 fault detection process in the embodiment of FIG. 2;

FIG. 5 is a diagram showing a flow chart of failure judgment processing of a BRI line in a line switching connection device according to a second embodiment of the present invention.

FIG. 6 is a flowchart of a PRI line failure determination process in the line switching connection device according to the second embodiment of the present invention.

FIG. 7 is a block diagram showing a configuration of a line switching connection device according to a third embodiment of the present invention.

FIG. 8 is a sequence chart showing an example of message exchange after line switching in the first to third embodiments of the present invention.

FIG. 9 is a sequence chart showing message exchange after line switching according to the fourth embodiment of the present invention.

FIG. 10 is a sequence chart showing another example of message exchange after line switching in the first to third embodiments of the present invention.

FIG. 11 is a sequence chart showing message exchange after line switching according to the fifth embodiment of the present invention.

FIG. 12 is a block diagram showing a state of line switching including switching on the extension side in a conventional CTI system.

FIG. 13 is a switching connection diagram of an external line and an internal line in the CTI system.

FIG. 14 is a C diagram according to a sixth embodiment of the present invention.
It is a block diagram which shows the structure of a TI system.

[Explanation of symbols]

10 INS network 20 line switching connection device 21 Switch 22 Monitor 23 Control unit 24 Condition setting section 30 Current Computer Telephony Server 40 Spare Computer Telephony Server 50 Spare terminal adapter 60 extension telephone 70 Extension switching connection device 71 Extension call monitoring unit

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 5K014 AA01 CA06 EA08 GA02                 5K021 BB10 CC11 DD02 EE00 FF04                       FF11                 5K035 AA07 BB04 CC05 DD01 EE06                       GG01 GG15 JJ02 LL18                 5K051 CC04 DD11 LL02 LL07                 5K101 LL03 MM04 QQ04 QQ20 VV03                       VV04 VV05

Claims (8)

[Claims] 1. A line switching connection device for selectively connecting a working line connected to a working terminal and a protection line connected to a protection terminal to an INS network, wherein the working line is connected in response to a switching control signal. A line switching circuit for disconnecting the connection between the line and the INS network to connect the protection line to the INS network, and a response message from the terminal side for a specific message from the INS network within a predetermined time. A line switch comprising a message monitor circuit for detecting and generating a no-response detection signal, and a control circuit for determining a line failure based on the no-response detection signal and generating the switching control signal. Connection device. 2. The working line and the protection line include at least two logical lines in one physical line, and when the control circuit detects a failure in one of the logical lines, the control line is in the same physical line. 2. The line according to claim 1, wherein the switching control signal is generated by detecting the use state of another logical line included in the above, and waiting for the end of the other logical line when the other logical line is communicating. Switching connection device. 3. The working line and the protection line include a plurality of logical lines in one physical line, each of the logical lines has a register for storing a failure status of its own line, and the control circuit is , The failure of each logical line is judged and the register of the logical line is set upon detection of the failure, or the register of the logical line is reset upon recovery from the failure, and the number of the set registers is predetermined. The line switching connection device according to claim 1, wherein the switching control signal is generated when the threshold value is exceeded. 4. The switching connection condition setting circuit capable of setting a predetermined line switching connection condition, wherein the control circuit switches the connection from the protection line to the working line. The line switching connection device according to claim 1, wherein the switching control signal is generated on the basis of the condition set for. 5. The line switching connection device according to claim 1, wherein the message monitor circuit does not generate the non-response signal only within a certain time after performing the line switching connection process. 6. The line switching connection device according to claim 1, wherein the control circuit does not generate the switching control signal within a fixed time after performing the line switching connection process. 7. The message monitor circuit should not generate a response message to a specific message from the backup terminal or the INS network within a predetermined time only within a certain time after performing the line switching connection process. The line switching connection device according to claim 1, wherein the line switching connection device is configured to detect the non-response detection signal. 8. A second switching connection circuit for switching and connecting a plurality of extension terminal devices to each of the working terminal or the backup terminal, and each of the extension terminal devices according to a second switching control signal. A second switching connection circuit for disconnecting the connection with the active terminal to connect each of the extension terminal devices to the spare terminal, and a call state of each of the extension terminal devices passing through the second switching connection circuit. When a monitoring circuit for monitoring and generating a call state monitoring signal indicating the call state, and switching connection processing between the working line or the protection line and the INS network are performed, the call is terminated based on the call state monitoring signal. The line switching connection device according to claim 1, further comprising: a second control circuit that generates the second switching control signal for each extension terminal device.