JPH04241554A - Routing control system - Google Patents

Abstract

PURPOSE:To obtain the efficient routing control system by speedily selecting a detour route enabling transmission to the network of the final purpose and reducing a busy state when there are plural detour routes. CONSTITUTION:Concerning this routing control system, plural private automatic telephone exchanges 1-3 are connected to a common line signal system, and central controllers 1b-3b detect the busy states for the specified line groups of the respective private automatic telephone exchanges 1-3. Then, the busy states are informed of the other private automatic telephone exchanges 1-3 by a common line signal and the private automatic telephone exchanges 1-3 receiving the common line signal store the busy states in storage devices 1c-3c and execute transmission after the detour to the route, where an idle line is existent in the line group, while referring to the storage devices when all the housed line groups are occupied in the case of executing transmission to the line group by the central controller of each private automatic telephone exchange.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a private automatic branch exchange (hereinafter referred to as PBX) connected by a common line signaling system, in which each PBX accommodates a group of lines that can be connected to the same network. The busy status of all line groups is set to other P.
The present invention relates to a routing control method for notifying a BX and efficiently making a detour call to a direction that will not encounter a busy line when all lines accommodated by the own PBX are busy for making calls to that network.

0002

[Background Art] Conventionally, when a PBX extension terminal makes a call to a certain network and encounters a group of lines being busy, if there is another line that can make a call to this network, a detour call is made to that line. It was controlled to

[0003] A conventional routine control system will be explained below with reference to the drawings. FIG. 11 is a block diagram illustrating a conventional routing control system, and shows an example of a network of exchanges connected by a dedicated line.
, PBX2, and PBX3 are connected by dedicated lines, and extension terminals 1a, 2a, and 3a are connected to these PBXs 1 to 3, respectively.
It accommodates.

Further, each of the PBXs 1a, 2a, and 3a is connected to a relay exchange 4 through a dedicated line, and the relay exchange 4 is connected to each of the networks 5a to 5n.

Next, the operation will be explained. Extension terminal 1
When a makes a call to the network, the connection is made using the line between the PBX 1 and the relay exchange 4. At this time, if the line group is all busy, the line between PBX1 and PBX2 is used, and the PBX
2 to a transit exchange 4.

[0006]Furthermore, when the line group between PBX1 and PBX2 is also all busy, they are connected via PBX3. As shown in FIG. 12(a), this connection condition is as shown in FIG. This is a detour call to line L3.

Similarly, as for the extension terminals 2a and 3a, as shown in FIGS. 12(b) and 12(c), respectively, when the line L1 group is all busy, a detour call is made to the line L2.

Under the above control conditions, for example, when the extension terminal 1a makes a call to the network, the PBX 1 and the relay exchange 4
If the line group between them is all busy, a call is made to the line between PBX1 and PBX2, but there are times when the line group between PBX2 and trunk exchange 4 is busy on PBX2, and in this case, Extension terminal 1 could not make a call to this network.

[0009] In addition, if PBX1 and PBX2 are connected using the common line signaling method, after detouring to PBX2, the PBX
PBX 1 can receive a common line signal informing that the line between PBX 2 and trunk exchange 4 is busy and cannot make a call.By receiving the common line signal, PBX 1
The detour call to PBX 2 was canceled and the detour call was made again to PBX 3 to reduce busy times when making calls to the network.

0010

[Problem to be Solved by the Invention] In the above-mentioned conventional technology, when there are multiple detour routes, even if the detour destination encounters a busy call after making a detour call, it is not possible to make a call to the remaining detour route. However, the efficiency of line usage was not good.

[0011] Furthermore, when connected using the common line signaling system,
Once you make a detour call, you can re-call the remaining detour route by receiving a common line signal indicating that the call could not be made because all lines were busy, but it took a long time to connect.

[0012] An object of the present invention is to provide a routing system that can quickly select a detour route that can be sent to the final destination network when there are multiple detour routes, reduce busy times, and perform efficient routing. The objective is to provide a control method.

[0013]

[Means for Solving the Problems] In order to achieve the above object, the routing control system of the present invention provides a method for controlling a plurality of on-premise automatic telephones connected by a common line signaling system and each accommodating a group of lines connected to the same network. a storage device that belongs to each private automatic telephone exchange and stores at least the busy status of the line group; and a storage device that is housed in each of the private automatic telephone exchanges and constantly monitors the busy status of the line group. At the time when the line transitions to busy or when an idle line occurs from all busy lines, a common line signal is used to notify a predetermined private branch automatic telephone exchange and store it in the storage means. When a call is made and the line group of the private automatic telephone exchange to which it belongs is found to be busy, the contents of the storage device are referred to to determine the busy state of the line group accommodated in another automatic telephone exchange. The system is equipped with a central control unit that identifies the call and automatically routes the call to a private automatic telephone exchange where an idle line exists.

[0014]

[Operation] In the present invention, the central control unit belonging to each private automatic telephone exchange constantly monitors the busy status of a specific line group, and signals a common line when a transition occurs to full-busy or an empty line occurs from full-busy. This notification is sent to other private automatic telephone exchanges, and upon receiving the notification, the private automatic telephone exchange stores the line status in its storage device, and the extension terminal belonging to each private automatic telephone exchange makes a call to each network and sends a message to each automatic telephone exchange. When all dedicated line groups are busy, a detour route is determined by referring to the contents of the storage device.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the routing control system of the present invention will be described below with reference to the drawings. FIG. 1 shows an example of a private automatic telephone exchange network configuration according to one embodiment.

In FIG. 1, the same parts as those in FIG. 11 will be described with the same reference numerals. In FIG. 1, each of the PBXs 1 to 3 includes a central control unit (hereinafter referred to as CPU) 1b, 2b, 3b that controls the entire exchange, a memory that stores various programs such as an exchange operation control program, station data, various tables, etc. Device (hereinafter referred to as MEM) 1c, 2
c, 3c, common line signaling equipment (hereinafter referred to as CSE) 1d, 2d that transmits and receives control signals different from speech signals during call control
, 3d, time division switches 1e, 2e, 3e, and extension terminals 1a, 2a, 3a.

Further, as shown in FIG. 1, PBXs 1 and 2 and PBXs 1 and 3 are connected by a common line signaling system, and communication links 11 and 12 and CSE 2d are used for communication.
1d, 1d and 3a by signal links 13 and 14 for transmitting signals other than telephone calls.

Further, each of the PBXs 1 to 3 is connected to the trunk exchange 4 by dedicated lines 1f, 2f, and 3f, and when making a call from an extension terminal to each network 5a to 5n, the dedicated lines 1f, 2f, 3f are connected to the relay exchange 4.
3f and is connected via the relay exchange 4.

FIG. 2 shows the connection route when the extension terminal 1a makes a call to each network in the network of FIG. 1, and FIG. This shows the state in which the signal has been captured and transmitted.

In addition, FIG. 2(b) shows that when the line group of the dedicated line 1f is all busy, it is recognized that there is an idle line in the dedicated line 2f accommodated in PBX2, and a detour call is made to the route of PBX2. It represents the state of being.

Furthermore, in FIG. 2(c), it is recognized that the line groups of the leased line 1f and the leased line 2f are all busy, and that the leased line 3f accommodated in the PBX 3 has an idle line, and
This shows a state in which a detour call is made to the route of BX3.

[0022] The priority order of the connection route when the extension terminal 1a makes a call is: Dedicated line 1f → Dedicated line 2f → Dedicated line 3.
f.

FIG. 3 shows the transmission and reception of common line signals for realizing the connection control shown in FIG. 2. here,
301 is a common line signal (hereinafter referred to as a line status notification signal) that notifies the busy status of the line group of the dedicated line 2f or 3f. CPU2b and 3b of PBX2 and 3 are MEM2
According to the programs stored in c and 3c, the busy state of the line groups of dedicated line 2f and dedicated line 3f is constantly monitored, and when the state changes to all busy state or an empty line occurs from all busy state. Then, send the line status notification signal 301 to the PBX.
1 via the signal link 13.

When the PBX 1 receives the line status notification signal 301, it analyzes its contents and stores the line status of the PBXs 2 and 3 in the MEM 1c. The extension terminal 1a housed in the PBX 1 makes a call to each network, and if all the lines of the dedicated line 1f are in the middle, the MEM 1c is referred to and a detour route is determined.

[0025] Furthermore, the line status notification signal 301 is transmitted to the PBX
In order to refresh the MEM 1c of the PBX 1 when the call control signal is reset, the call control signal is retransmitted periodically or aperiodically to the extent that it does not affect the transmission and reception of the call control signal.

FIG. 4 shows CCITT Recommendation No. 7 is a diagram showing the structure of a level 4 signal for call control specified by the 7 signaling system. In FIG. 4, a label 15a is an information area indicating a call to be controlled in the transmission and reception of signals. It includes the originating station number indicating the originating telephone exchange and the destination station number indicating the destination telephone exchange of the transmitted signal, and is also a line number assigned to each call link agreed in advance between the telephone exchanges. It is configured.

Further, the heading code 15b is an area representing the type of signal. Additionally, additional information area 1
5c is given to various signals when additional information is particularly required, and various additional information can be sent and received by making prior arrangements between each telephone exchange. This is an area where this is possible.

FIG. 5 shows an example of the configuration of the line status notification signal 301 shown in FIG. 3. The line status notification signal 301 includes a label 301a, a heading code 301b indicating that it is a line status notification signal, a line type 301c indicating which route the line group belongs to, and that the line group of the line type 301c is all busy. It consists of a line status 301b that indicates whether there is a line status.

Furthermore, since the line status notification signal 301 is transmitted and received independently of the call links 11 and 12, the line number in the label 301a is a signal that is not used.

Furthermore, the line status notification signal 301 is
ITT Recommendation No. This is a new common line signal negotiated between telephone exchanges that is not specified by the 7 signaling system.

FIGS. 6 and 7 are flowcharts for explaining the processing of each PBX that controls transmission and reception of the line status notification signal 301 in FIG.

FIG. 6 is a flowchart showing the process of monitoring the status of the line group within the own station and notifying other stations of the line status. The flowchart in Figure 6 is based on the PBX in Figure 3.
Although the processes of 2 and 3 are shown, PBX 2 will be explained below as an example.

In the PBX 2, when the line group status monitoring program is activated periodically, the line group status monitoring program (FIG. 3)
(dedicated line 2f) and a signal link (signal link 13 connecting PBX 2 and PBX 1 in FIG. 3) for notifying the above-mentioned monitoring result by a common line signal are extracted in step 601 and are subject to control in subsequent processing.

Note that the line group whose status is to be monitored is stored in advance in the MEM as station data, and determined by referring to this MEM.

After determining the line group to be monitored, step 6
At step 02, it is checked whether the line group is all busy, and at step 603, it is determined whether the status has changed from the previous status.

If a change in state is detected, the process moves from step 603 to step 604, and the content of the change is identified.

In this step 604, if the state changes from the empty state to the all-busy state, the process moves from step 604 to step 605, and the line status notification signal 301 is edited to indicate that this line group is all-busy. Create a common line signal to transmit.

Further, in step 604, if the all-busy state changes to the idle state, the process moves from step 604 to step 606, and the line status notification signal 301 is edited to indicate that there is an idle line in this line group. Create a common line signal to transmit.

If there is no change in the state of the line group in step 603, the process moves from step 603 to step 607, in which the usage state of the signal link is identified.

[0040] Here, when it is frequently used for transmitting and receiving other call control signals (when there is a lot of CSE processing), no processing is performed.

[0041] If there is a margin in the signal link, the process moves from step 607 to step 608, and in step 608, the current status of this line group (all busy or there are idle lines) is included in the line status notification signal 301. Edit and create common line signals to send. After creating each of the above common line signals, processing for transmitting these common line signals to this signal link is performed in step 609.

[0042] This process immediately notifies other stations of the status when the status changes, and when there is no status change, refreshes the MEM of the other station when there is room for processing without affecting call control. It is sending a signal to

FIG. 7 is a flowchart showing the processing when the line status notification signal 301 is received. This flowchart shows the processing when PBX1 receives the line status notification signal 301 from PBX2 and 3 in FIG.

First, when the line status notification signal 301 is received, in step 701 the signal generation source PBX (PBX 2 or 3 in FIG. 3 is PBX 3), line type (leased line 2f or Dedicated line 3f) and line status (all busy or idle lines) are extracted, and then, in step 702, M corresponding to the route where this line group exists is extracted.
Write this line status to the EM storage area.

FIG. 8 shows an example of a data structure for storing the line status and detour destination. 8 in Figure 8
01 indicates the entire control data, and within the control data 801, control data for each line type is assigned.

Reference numeral 802 in FIG. 8 is an area for storing the route number of the detour destination to be used when all lines in the line group are busy. 80
3 is an area for identifying whether or not the detour route 802 is possible.

In other words, the detour identification data 803 is an area where, when the line status notification signal 301 is received, the line status in the signal is set corresponding to the route, and this detour destination line group is all busy. This is for identifying whether or not there is a file (this is a storage area stored in step 702 in FIG. 7).

[0048] Detour route 802 and detour identification data 80
3 can be set in multiple numbers for each line type, and are set according to the detour priority order.

FIG. 9 shows a case where an extension terminal of a private automatic telephone exchange makes a call to a group of lines (for example, in FIG. 1, when the extension terminal 1a makes a call to the trunk exchange 4 in order to connect to each network) ) is a flowchart diagram illustrating processing.

First, when an extension terminal performs a call operation to a line group, it is determined in step 901 whether or not all of the line groups accommodated in the local station are busy. As a result of this check, if an idle line exists in the line group in step 902, the process branches from step 902 to step 903, and in step 903, the line is captured and a call is made.

Further, in step 902, if all lines are busy, the process proceeds from step 902 to 904, and in step 904, a detour route 802 is extracted from the control data 801 according to the line type.

Next, in step 905, the detour route 802
If the caller is not registered, processing to disable the call, such as sending a busy tone to the calling extension terminal, is executed.

Further, in step 905, if the detour route 802 is registered, the process advances from step 905 to step 906, and the detour identification data 803 is identified.
The status of the line group in the detour destination PBX is checked, and it is determined whether or not the detour route 802 can be connected to the line group after the call is made.

As a result of this identification, if the detour identification data 803 indicates that there are idle lines, the process moves from step 906 to step 907, and in step 907 it is determined whether all the lines of the detour route 802 are busy or not. If there is an idle line in the line group in the next step 908, the process moves from step 908 to step 909, and in step 909 the line is captured, the call is made, and the detour destination is identified. Make a call to the desired line using the PBX.

Further, in step 908, if all lines of the detour route 802 are busy, the process proceeds from step 908 to step 910, extracts the next detour route 802 from the control data 801, and repeats the process in step 908. Returning to 905, the same processing is repeated from step 905.

Furthermore, in step 906, if the detour identification data 803 indicates that all calls are in progress, the call processing for the detour route 802 is not performed and the next detour route 802 is used.
Extract and continue processing.

As described above, in the network of FIG. 1, when the extension terminal 1a makes a call to the network, PBXs 2 and 3
Since it is possible to know whether all dedicated lines 2f and 3f are busy, detours can be made efficiently when the dedicated line 1f is busy.

However, due to time differences in the transmission and reception processing of common line signals, the states between PBXs may not match for a while, so there are cases where detour calls are made even when the line group of the detour destination PBX is full. do.

In this case, as shown in FIG. 10, similar detour control is possible by performing processing to send a call to the next detour route by receiving a line group busy signal.

FIG. 10 shows the processing when all the lines in the line group are busy and the detour call occurs at the same time. Here, 1001 is a common line signal for activating other stations, and 1002 is a common line signal indicating that all line groups are busy in response to a line group origination request.

As shown in FIG. 10, when the line group is all busy and the detour call occurs at the same time, the originating PBX sends a line status notification signal 301 indicating that the line group is all busy.
is not received, and the detour control data 803 shows that there is an empty line, so the detour call is made, a start signal 1001 notifying a call request to the line group is sent, and the call is made to the detour destination PBX. .

[0062] When the detour destination PBX receives the activation signal 1001, since all lines are already busy, it transmits a line group busy signal 1002 to notify the originating PBX that a call to the line group could not be made. .

At the originating PBX, the line group busy signal 1002
When the call is received, it is possible to relieve the call in which the above-mentioned state has occurred by performing the outgoing processing for the next detour route 802.

[0064]

As described above, according to the present invention, each of a plurality of PBXs constantly monitors the busy state of a specific line group, notifies other PBXs of the busy state using a common line signal, The PBX that receives this common line signal stores it, and also refers to the memorized busy state when all of the accommodated line groups of each PBX are busy, and detours to a route where there is an empty line in the line group. Since I made the call, the detour destination PBX
It is possible to recognize in advance the busy status of the final target group of lines accommodated in the network, and therefore it is possible to make efficient detour calls. Furthermore, it is possible to eliminate lines being busy after making a detour call.

[Brief explanation of the drawing]

FIG. 1 is a network configuration diagram in an embodiment of the routing control method of the present invention.

[Figure 2] (a) is the connection route when an extension terminal makes a call to each network in the network of Figure 1, and shows the connection route when the extension terminal makes a call to each network.
1 is an explanatory diagram of a state in which a line of a dedicated line 1f accommodated in 1 is captured and a call is made. (b) is the same connection route, and when all the lines on the dedicated line 1f are busy, it is confirmed that there is an empty line on the dedicated line 2f accommodated in PBX2, and PBX2
FIG. 2 is an explanatory diagram of a state in which a detour call is made to a route. ,(c)
is the same connection route, recognizes that the line groups of leased line 1f and leased line 2f are all busy, and that there is an idle line on leased line 3f accommodated in PBX3, and detours to the route of PBX3. FIG. 3 is an explanatory diagram of a state in which a call has been made.

FIG. 3 is a connection diagram showing a transmission/reception state of common line signals in FIG. 2;

FIG. 4 is a basic configuration diagram of a common line signal applied to the present invention.

FIG. 5 is a configuration diagram of a common line signal used in the present invention.

FIG. 6 is a flowchart showing control for monitoring the status of a line group in the present invention.

FIG. 7 is a flowchart showing control when receiving a common line signal applied to the present invention.

FIG. 8 is a data configuration diagram for identifying detour routes and busy information applied to the present invention.

FIG. 9 is a flowchart showing the flow of the PBX call control process according to the present invention.

FIG. 10 is a sequence explanatory diagram showing the flow of processing when a detour call and an all-busy state collide in the present invention.

FIG. 11 is a network configuration diagram of a conventional routing control method.

FIG. 12 (a) shows the network connection state when the PBX makes a call in the conventional routing control system; the call is made to line L1, but during the line L1 group conversation, the call is detoured to line L2; This is an explanatory diagram of a state in which a detour call is made to line L3 when both L1 and L2 are busy. (b) This is an explanatory diagram showing the state of connection to the same network, and a state in which a detour call is made from the PBX2 to the line L2 when the line L1 group is all busy. (c) indicates the connection status of the same network,
FIG. 6 is an explanatory diagram of a state in which a detour call is made from the PBX 3 to the line L2 while the line L1 group is all busy.

[Explanation of symbols]

1-3　　　　　　　　Automatic telephone exchange 1a-3a　　　　Extension terminal 1b-3b Central control device 1c~3c　　Storage device 1d to 3d Common line signal device 1e~3e　　　Switch 1f to 3f Dedicated line 4 Trunk exchange 5a-5n Net 11,12 Communication link 13,14 Signal link 301 Line status notification signal 801 Detour control data

Claims (1)

[Claims] Claim 1: A plurality of private automatic telephone exchanges each accommodating a group of lines connected by a common signal line system and each connected to the same network; A storage device for storing data and a common line signal stored in each of the private automatic branch telephone exchanges constantly monitor the busy status of the line group and generate a common line signal when the line transitions to full-busy or when an idle line occurs from full-busy. to notify a predetermined private automatic telephone exchange to store it in the storage means, make a call to each network belonging to each of the private automatic telephones, and when the line group of the private automatic telephone exchange to which it belongs comes across to be in full service; a center that refers to the stored contents of the storage device to identify the busy state of the line group accommodated in another automatic telephone exchange and automatically detours the call to a private automatic telephone exchange in which an idle line exists; Routine control system with control device.