JPH03143150A - Received call transfer and connecting system in private branch exchange - Google Patents

Abstract

PURPOSE:To shorten a telephone distance in a public network as much as possible by providing a received call transfer function and a tandem connection function in a private branch exchange and transferring a received call sent from an extension to a trank line side and a received call from the public network to a leased circuit. CONSTITUTION:When a private branch exchange PBX1 transmits 0A2B2...I2 succeeding to a dial '0' from a subscriber Be of an extension, a leased circuit of a region Z2 as an output connecting route, namely, a route to a private branch exchange PBX2 is selected. When a subscriber Cs of a public network N2 in the region Z2 is connected to a subscriber Ce of an extension in the private branch exchange PBX1, 1XXXX of a number in the leased circuit network of the PBX1 is dialled successively to a public network number assigned to the trunk line trunk COT4 of the private branch exchange PBX2. In the private branch exchange PBX2, a leased circuit trunk TRK4 connected to the PBX1 is captured and a path from COT4 to TFT2 and to TRK4 is set.

Description

[Detailed Description of the Invention] [Kneeling Business - Hi's Utilization Molecule FF] The present invention relates to a method for interconnecting a private line network with a private branch exchange and a public network, and particularly relates to a method for interconnecting a private branch exchange with a public network, and in particular, a method for interconnecting a private branch exchange with a public network using the incoming call transfer function. This invention relates to a call transfer connection method in a private branch exchange that shortens the communication distance between a called subscriber and a dedicated line network.

[Conventional technology]

The connection within a dedicated line network consisting of a conventional private branch exchange and the connection between this dedicated line network and a public network are described in, for example, "Introduction to Digital PBX" (1988) edited by Sugioka, Vol. 125, published by Ohmsha.
126, each of which is considered separately. Therefore, the higher the frequency of access to the public network from the extension telephone of the private branch exchange, the higher the call charges will be. Furthermore, in public networks, call charges are calculated taking both call distance and call time into consideration, so when using a public network, the longer the call distance, the more call charges will be incurred.

[Problem to be solved by the invention]

In the above conventional technology, the connection within the dedicated line network consisting of a private branch exchange and the connection between this dedicated line network and the public network are considered to be separate, so the frequency of access from the extension telephone of the private branch exchange to the public network is taken into account. ;The higher the number, the higher the call charges will be. Therefore, for users who have a leased line network, if the leased line can be used for part of the above connection, the payment of call charges will be reduced. for example,
When a user who owns a leased line between Tokyo and Osaka connects from an extension line in Tokyo to a public subscriber in Osaka, the user must pay a call fee proportional to the call distance between Tokyo and Osaka and the call flit. Must be. However, the connection between Tokyo and Osaka is not via public network:! , l/, If this can be done using a private line, the length of the call using the public network will be greatly shortened, and the cost of the call will be reduced proportionately. For this purpose, when connecting to a public network subscriber from an extension telephone, it is sufficient if there is a method in which a private branch exchange closest to the destination subscriber is used to receive the call to the public network subscriber.

The same thing can also be said when connecting from a subscriber of a public network to an extension of a private branch exchange of a private line network.

Currently, the public network subscriber can connect to the extension telephone of the private branch exchange by P B X dial-in, but only the J:J line connection is available between the public network and the private branch exchange.

If calls from the public network subscriber can also be received by other private branch exchanges using a dedicated line, the call charges for the subscriber can be reduced as the call distance is shortened.

The purpose of the present invention is to provide a call transfer function in a private branch exchange in order to solve the above-mentioned problems, and to transfer an incoming call from a private line made from an extension telephone to the central office line or to transfer an incoming call from a public network. To provide a call transfer connection method in a private branch exchange, which can reduce the call charge by shortening the call distance within the public network as much as possible by transferring the call to the private line side.

[Means for Solving Six Problems] In order to achieve the above object, the method for connecting a call transfer in a private branch exchange according to the present invention provides a call transfer trunk or relay connection function in the private branch exchange and a route selection function using public network number translation. By providing a route selection function by translating numbers within the leased line network, incoming calls from the leased line made from an extension phone are forwarded to the central office line, or incoming calls from the public network are transferred to the leased line. This feature makes it possible to transfer incoming calls to the other party.

[For production]

The call transfer connection method in the private branch exchange uses a route selection function based on public network number translation to expand the area number and, if necessary, the local number, and decide whether to select a central office line trunk or a dedicated trunk. With the route selection function based on leased line network number translation, you can expand the leased line network number and decide whether to select your own monthly extension IT call or leased line trunk connection, and use this route selection function and call forwarding trunk or The relay connection function allows calls from an extension to be relayed to another private branch exchange via a dedicated line, and calls from the public network can be routed to 1.1
Relaying to other private branch exchanges via the F line becomes an I+J function.

〔Example〕

An embodiment of the present invention will be described below with reference to Figures ↓ to 3.

FIG. 1 shows the private branch exchange according to the present invention: ? ' is a relay method r threshold showing an example of a communication transfer connection method.

In Figure 1, Ite, As, Bs, Cs, and Ds are the public spring network participating ministries, As is accommodated in the public 114N+ of area Z1, and t
3s, Cs, and Ds are accommodated in the public network N2 in area Z2. PBXI and PBX2 are private branch exchanges, each with area Z.
1+Z2, and are connected to each other by dedicated lines 1 and 2. Ae, Be, Ce, De are extension subscribers; Ae, Be
, Ce are accommodated in the private branch exchange PBXI, and De is accommodated in the private branch exchange PBX2. C0Tl to C0T4 are central office line trunks used to connect central office lines 3 to 6 with the public network NlvN2, and TRKI to TRK4 are private branch exchanges P.
Dedicated line trunk used for connecting 1iAl, 2 between BXI and PBX2, O8I to O83 are outgoing senders that send out selected digits, IRI to IR3 are incoming registers that receive selected digits, TFTI, "ll'FT2 is incoming call A call forwarding trunk that forwards calls.

Next, the incoming call transfer connection operation shown in FIG. 1 will be explained with reference to the connection operation flow of FIG. 2 and the third TA for two connection types: connection from a private line network to a public network and connection from a public network to a private network.

FIG. 2 is a flow diagram of the connection operation from the dedicated line network of FIG. 1 to the public network. Taking as an example the case where a call is received from the extension subscriber Be of the private branch exchange PBXI shown in FIG. 1 to the public subscriber Bs, the connection operation will be explained with reference to the connection operation flow shown in FIG. 2. First, when the extension subscriber Be makes a call to the public network, it is assumed that he dials as follows, as in the past.

'0'(DTt'? Hearing) 'O' A B -
---I first dial l Ot is not required when an extension subscriber connects to a subscriber in the leased line network, but it is necessary to notify the private branch exchange that the connection is to the public network. be. In the conventional system, when a dial "O'" is received from an extension subscriber, the central office line trunk and the extension telephone are connected and a call is made from the central office trunk to the public network.

The public network transmits the caller's (DT tone), and the extension subscriber listens to this DT tone when the central office trunk is sent out.゛↑After confirmation, the extension subscriber dials the public network number. On the other hand, in the method of the present invention, when the private branch exchange receives the extension subscriber's dial ``O'', it identifies that it is a public network connection as in the conventional system. Based on this identification, the private branch exchange in turn sends out to the extension subscriber a tone equivalent to the dial tone sent out by the public network. After hearing this sound, the extension subscriber calls the OA which is the number to connect to the public network.
n...■ (Long distance connection) or...FGHI
(local connection). The private branch exchange receives the dialed digits and determines the outgoing connection route. Next, the method for determining the outgoing connection route will be described.

There are currently N private branch exchanges PBXI to PB in the leased line network.
It is assumed that there is an XN network and these constitute a network using dedicated lines. In addition, the private branch exchanges PBXI to PBXN are installed closest to areas z and -zN in the public networks N and ~NN, respectively, and the public network area codes in these areas are A, B, ... in area Z1.・A2 in area Z2
Assume that AN BN... is assigned to B2..., area ZN. In this configuration, the relationship between dialed numbers and outgoing connection routes is made to correspond as follows.

(Dial number) (Outgoing connection route) (1) A
+ B1... (inside the city): Local PBXI's central office line trunk The connection operation flow in Figure 2 shows the case (2) above. Case (L) is a central office trunk connection like the conventional system, and cases (2) to (N) are (2).
) Since the connection operation is similar to that in case (2)
The operation in this case will be explained next.

OA2 B following dial 101 from extension subscriber Be
2... When the private branch exchange 1-' B
Select the route to BX2. It then seizes the leased line trunk 1'RKI connected to the region'/, 2)) 13
Activate the service trunk 'l' RK 2. Then T)
I3
B2...Sent as I2 from the outgoing sender O8l to the person register IRI of private branch exchange 1) B x 2. Private branch exchange1. ) At B X 2, this number is received and 3 is analyzed, and since the beginning of this number is i 0 t, it is identified that it is a link to the station line of area Z2. After this identification, dedicated line 1 to rank TRK2 and central office line trunk C are
0T3 is connected to the first destination (a forwarding trunk "I' F
T RK 2 'I'I'''l'
1- Set up a path for COI3 and send a call from C○1゛3 to public network N2 in area Z2. In this case, if P13X2 and public network N2 of area Zz are in the same city, A2B2...I
2.

From the perspective of public network N2, if PBX2 is in an out-of-town area, it is OA2B2.
...I2 to PBX, area Z from output sender O83 of 2
2 to the public network N2. This is received on public network N2.
n L, join:? identifying that the call is to tBs;
Call join ff I3 s. Public network NZ has subscriber t
3 At the same time as sending a paging signal to s, private branch exchange P
13 Sends a ringing signal tone (RT3T) to X, 2.

From this, P B X 2 C0T3-TFTI-TRK
With the path of Z, the branch exchange I) sends B'F to the originating subscriber Bo of X, 1. Then joined ff 13s
Be-TRKI-TRKZ-TI"J'1-
By setting a path between COT3 and Bs, a call can be made between the extension subscriber Be and the subscriber 1I3s of the public network NZ. After that, Be-TRKI-TRKZ-TF was terminated and disconnected.
The path between TI-C0T3-Bs is opened.

FIG. 3 is a flow diagram of the connection operation from the public network to the dedicated line network in FIG. 1. Ground t4 in Figure 1. Taking as an example the case where subscriber Cs of ZZ's public network N2 connects to extension 500 of private branch exchange PBXI, the connection operation will be explained with reference to the connection operation flow shown in FIG. It is now assumed that the leased line network identification number structure consists of the identification numbers and extension numbers of the private branch exchanges PBXI to PBXN. Here, private branch exchange P13X]
, PBX2 are given identification numbers (17 and 12+, respectively, and the other PBX3 to PBX and N are given identification numbers) 3' to 18'. Figure 3 shows the connection operation flow for this example.
Using this example, the connection operation from the public network to the private line network will be explained next.

When connecting from subscriber Cs of public 114N2 in area Zz to extension subscriber Ce of private branch exchange P HX 1, the third
As shown in the figure, private branch exchange PBX, 2 central office line trunk C
The public network number assigned to 0T4 followed by p13x
When you dial IXXXX, the private line network number of t,
This dedicated line network number is sent from the public IAN 2 in area Z2. Input register IR3 in private branch exchange PBX2
receives this dialed number, analyzes the received 4M number, and selects a route to the private branch exchange)) BXI since the private line network number is 1xxxx. Then PBX
4 is captured in the leased line trunk TR connected to I, and a path between COT4-TF'r2-TRK4 is set up. Then from dedicated line trunk 'I' RK 41)
Opposite dedicated line trunk of BXI "1" P from RK 4
Raise BXI's opposite leased line trunk "1' RK 3"
! After II, I) From the output sender O32 of I-3X 2 to the input register IR2 of the PBXI within the dedicated line network! , >7.
IXXXX is sent. The private branch exchange PBXl receives and analyzes this number, identifies that the call is to the extension telephone Ce, and then calls the extension subscriber Ce.

Then, after the response from extension subscriber Ce, Cs-G O'1
．． "4- T F "I'2- T RK4-
By setting a path between TRK3 and Ce, a call can be made between the public network subscriber Cs and the extension subscriber Ce. After that, Cs-C0T4-TFT2-TRK4 is terminated and disconnected.
-TRK3-C, the path is opened.

Next, a call transfer trunk TF"l'l, which has both outgoing and incoming terminals used for both of the above two types of connections,
The TFT 2 is for connecting the path between the office lines 5 and 6 and the dedicated line 1.2, and is housed on either the office line side or the dedicated line side. When accommodated on the central office line side, it can be connected as a combination of extension incoming and outgoing calls, and when accommodated on the dedicated line side, connection can be controlled as a combination of incoming and outgoing connections. Also, call forwarding trunk T F Tl,
T F1-2 is not used, and central lines 5, 6 and 1. Body line 1
, 2 can also be made under the same control as the relay connection.

〔Effect of the invention〕

According to the present invention, a private branch exchange is provided with an extension I'I!7 transfer function or a relay connection function, and an extension I'I! Calls originating from a private line are forwarded to the central office line, or calls received from the public network are forwarded to the leased line, thereby making calls within the public network possible. Because the distance can be kept as short as possible, public networks use a system that calculates call charges by considering both call distance and call time. Therefore, users who have a leased line network over a wide area can use the leased line network to connect even long distances, which can be economically advantageous. , it is possible to provide a method for connecting a mobile phone that is effective for such users.

[Brief explanation of the drawing]

Fig. 2 is a relay system diagram showing an embodiment of the incoming call speed connection method in a private branch exchange according to the present invention, Fig. 2 is a flowchart of connection operation from the dedicated line network to the public network in Fig. 1, and Fig. 3 is a 1st
FIG. 2 is a flow diagram of a connection operation from the public network to the private line network shown in the figure. 1.2... Dedicated line, 3-6... Central line -21+ 22.
...Region, NlyN2...Public network, As-D
s...Ministry of Public Network Access, 1' B X, 1. I-'
B
C0TI-CO'r4... Office line trunk, TRK1~
'I' RK 4... Dedicated line trunk, O81~08
3...Output sender, IRI~IR3...Input register,
'I' F T1. 'I'I-' T2...Call transfer trunk.

Claims (1)

[Scope of Claims] 1. Equipped with both a central office line trunk for connection to the public network and a private line trunk used for connection within the private line network, and as an outgoing connection route selection function, translation of outgoing digits from an extension line is provided. In private branch exchange equipment that has a function to identify whether to connect to a public network or a leased line network, a call transfer trunk or relay connection function with both outgoing and incoming terminals is installed, and the outgoing connection to the public network is When a connection route is selected, a function to identify whether to connect directly to the public network or connect to the public network from another private branch exchange via a leased line by translating the area code and station number of the calling number, and the latter connection A function that sends the toll number and central office number in addition to the subscriber number to the destination private branch exchange, and a function that sends the toll number, central office number, and subscriber number as selected digits from the calling private branch exchange via the leased line. It has a function to identify it as a public network connection call, and if this call is provided with the above-mentioned call transfer trunk, it is connected to the receiving side of the call transfer trunk, and the calling side terminal makes the call to the public network and connects to the public network. Equipped with a function to send out the necessary selection digits, or, if this call is provided with the above-mentioned relay connection function, a function to connect to the dedicated line side of the relay connection function and send out the necessary selection digits from the central office line side, A call transfer connection method in a private branch exchange, which is characterized by enabling connection from a private line network to a public network and making calls using these functions. 2. Equipped with both central office line trunks for connection to the public network and leased line trunks for connection within the leased line network,
In a private branch exchange facility with an A function to translate and identify whether an incoming call is to one's own private branch exchange or another private branch exchange, and for calls connected to other private branch exchanges, calls from the public network are transferred when the above-mentioned call transfer trunk is installed. connects to the receiving side of the call transfer trunk, sends a call from the calling side terminal to the destination private branch exchange, and sends the numbers necessary for connection, or if this call is provided with the relay connection function described above, the relay connection A premises characterized by being equipped with a function of connecting to the office line side of the function and transmitting necessary numbers from the leased line side, and using these functions, it is possible to connect from the public network to the leased line network and make calls. Call transfer connection method in an exchange.