JPH11164012A - Public network connecting interface switching method and exchange - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attain economization and unitary management concerning a public network connecting interface switching method, with which an inter-station connecting interface and a subscriber's line interface are switched, and an exchange. SOLUTION: An exchange 10 of a communication entrepreneur housing general subscribers 15 is provided with the subscriber's line interface equipped with central office line trunks 3 and 4 or the like to be connected to an existing public network 20 and the inter-station connecting interface, to which a common line signal system is applied while containing a bidirectional trunk 2 or the like for inter-station connection, a subscriber condition management table and a service selection management table are formed in a main storage device 6 together with the contract condition of the general subscriber 15 or the like, a central control unit 5 identifies the request of a call originating subscriber and his contract condition or the like while referring to the main storage device 6, and whether the inter-station connecting interface or the subscriber's line interface is to be used for connecting processing is controlled. Further, in the case of the subscriber's line connecting interface, whether it is to be connected to an ISDN public network or to an analog public network is selectively controlled while referring to the subscriber condition management table.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a public network connection interface switching method and an exchange for connecting an exchange of a new type 1 telecommunications carrier accommodating general subscribers to an existing public network. The existing public network has a configuration for providing various services to subscribers. New type 1 telecommunications carrier NCC (New Common Carrie)
r) The exchange between the telecommunications carrier and the existing public network is accommodated so that ordinary subscribers can be accommodated in the exchanges and calls can be made with ordinary subscribers accommodated in the existing public network. Connected systems are known. In addition, even new type 2 telecommunications carriers have exchanges that accommodate general subscribers,
It is possible to connect to the existing public network.

[0002]

2. Description of the Related Art FIG. 11 is a schematic explanatory view of a conventional example.
00 is the exchange of the telecommunications carrier, 200 is the existing public network, 1
01 is a communication path device, 102 and 203 are two-way trunks,
103 is a private branch exchange (PBX), 104 is an ISDN line trunk, 105 is an analog line trunk, and 106 and 2
06 is a common channel signaling device (CSE), 107 is a central control unit (CC), 110 is a general subscriber, 111, 112, 1
Reference numeral 13 denotes a communication line, 114 denotes a signal line, 201 denotes a public network to which a common channel signaling system is applied, 202 denotes an ISDN or analog public network, and 204 and 205 denote subscriber circuits.

[0003] A communication line 111 between the existing public network 200 and the exchange 100 of the telecommunications carrier is equivalent to a relay line between stations using a common channel signal system, and control information is transmitted through the signal line 11.
4 and the common line signaling devices 106 and 206. Also, the existing public network 200 and the exchange 100 of the telecommunications carrier.
Are handled as ISDN and analog subscriber lines from the public network 200 side, and ISDN and analog office lines connecting the private branch exchange 103 and other exchanges from the exchange 100 side. Will be treated as That is, the existing public network 200 includes a public network 201 connected by an interoffice connection interface and a public network 202 connected by a subscriber line connection interface.

The exchange 100 of the telecommunications carrier establishes a connection between the existing public network 200 and the general subscriber 110 by the central control unit 1.
07, a bus is formed in the communication device 101 and a connection is established by an inter-office connection interface to which a common channel signaling method using the communication line 111 is applied, and a path is formed in the communication device 101, Call line 1
Compared with the case where the connection is made by the subscriber line connection interface by the connection lines 12 and 113, the former has higher line concentrating efficiency. Therefore, for a general call,
The connection to the public network 200 is established by the office line connection interface.

In this case, various types of control information are transferred in accordance with the common channel signaling system. In the public network 200, services to be provided are restricted according to contract conditions with the exchange 100 and the like. Therefore, the control information from the exchange 100 is determined, and it is determined whether or not the information conforms to the contract conditions. Only when the agreement is satisfied, the connection according to the request of the general subscriber 110 accommodated in the exchange 100 is performed. Through the processing, the requested service is provided from the public network 200 side.

When the general subscriber 110 is connected to the public network 200 through the subscriber line connection interface, the general subscriber 110 can be regarded as a subscriber connected to the public network 200 via the subscriber line. A service corresponding to the request of the user 110 can be provided from the public network 200. For this purpose, a private branch exchange 103 is provided, and connection to the public network 200 is established via communication lines 112 and 113 (subscriber lines).

[0007]

In order to provide a service which can be provided on the existing public network 200 to the general subscriber 110, the conventional exchange 100 of the communication carrier is as described above. , It is necessary to connect via a subscriber line connection interface.
It was necessary to provide. Therefore, there is a problem that the system cost increases. In addition, the private branch exchange 103 and the exchange including the central control unit 107 and the communication path unit 101 require double processing such as traffic control processing, and there is a problem that it is difficult to centrally manage the processing. SUMMARY OF THE INVENTION It is an object of the present invention to identify a request of a general subscriber and switch between an interoffice connection interface and a subscriber line connection interface to enable centralized management and reduce costs.

[0008]

According to the present invention, there is provided a method for switching a public network connection interface comprising the steps of: (1) providing a subscriber line connection interface to an existing public network 20 in a communication service exchange 10 accommodating a general subscriber 15; An inter-office connection interface to which a common channel signaling method is applied, including a step of switching between the subscriber line connection interface and the inter-office connection interface in accordance with the calling subscriber's request and the calling subscriber's contract conditions. It is a thing. Therefore, in the case of a contract condition for receiving a public service provided on the existing public network 20 without providing a private branch exchange, it is possible to switch to the interoffice connection interface. The connection processing can be performed so as to enable the public service by switching to.

(2) When a calling subscriber accommodated in the exchange 10 of the communication carrier requests a public service, either the subscriber line connection interface or the interoffice connection interface is used in accordance with the contract conditions of the calling subscriber. The method may include a step of performing a connection process by switching to a crab.

(3) When switched to the subscriber line connection interface, the ISDN is changed according to the contract conditions of the calling subscriber.
The method may include a process of performing connection processing for a public network or an analog public network. That is, the contracting condition of the calling subscriber is I
If connection to the SDN public network is possible, connection processing to the ISDN public network is performed.

(4) When the connection is switched to the subscriber line connection interface, the IS is set in accordance with the terminal attribute of the calling subscriber.
The method may include a process of connecting to a DN public network or an analog public network. That is, when the terminal attribute is the ISDN terminal, the connection processing to the ISDN public network is performed, and when the terminal attribute is the analog terminal, the connection processing to the analog public network is performed.

(5) When the connection is switched to the subscriber line connection interface, the IS is set according to the transmission capability of the calling subscriber.
The method may include a process of connecting to a DN public network or an analog public network. That is, if the transmission capability is a data call, connection processing to the ISDN public network can be performed, and otherwise, connection processing to the analog public network can be performed.

(6) The calling subscriber is switched to the interoffice connection interface to perform connection processing to the public network, and upon receiving a disconnection signal including reason information from the public network, according to the contract conditions of the calling subscriber. Switching to the subscriber line connection interface to determine whether to perform the re-call processing. Therefore, the re-call operation of the general subscriber 15 accommodated in the exchange 10 can be omitted.

(7) In the exchange 10 of the telecommunications carrier accommodating the general subscriber of the present invention and connecting to the existing public network, it is connected to the existing public network 20 as a subscriber line connection interface. The trunk trunks 3 and 4, the bidirectional trunk 2 connected as an interoffice connection interface to which the common channel signaling system is applied, the existing public network 20 and the general subscriber 15 via the trunk trunks 3 and 4 and the bidirectional trunk 2. , A central control device 5 for controlling the communication path device 1, and a main storage device 6 including a call control information area for storing call control processing information. Reference numeral 6 includes a subscriber condition management table storing contract conditions and the like corresponding to the subscriber number, and a service selection management table storing service types. Storage device 6 Referring to the subscriber condition management table and service selection management table, and has a configuration for performing the processing of switching the subscriber line connection interface and interoffice connection interface.

(8) The subscriber condition management table of the main storage device 6 has a configuration in which availability of public service, accessible public network type, terminal attribute, and transmission capability are set in correspondence with the subscriber number. It has.

(9) The service selection management table of the main storage device 6 has a configuration in which the service type of the public service connection, the general public subscriber connection, or the connection in the own network is stored in correspondence with the number of the service request. It is.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a diagram for explaining the principle of the present invention, in which 10 is an exchange of a telecommunications carrier, 20 is an existing public network,
1 is a communication path device, 2 and 23 are bidirectional trunks for interoffice connection, 3 is an ISDN line trunk, 4 is an analog line trunk, 5 is a central control unit (CC), and 6 is a main storage unit (M
EM), 7, 26 are common line signaling devices (CSE), 11,
Reference numerals 12 and 13 denote communication lines, 14 denotes a signal line, 15 denotes a general subscriber, 21 denotes a public network to which a common channel signal system is applied, 22 denotes an ISDN or analog public network, and 24 and 25 denote subscriber circuits.

When the central control unit 5 determines that the call is a general call based on the call information of the general subscriber 15, the central office 5 uses the inter-station connection interface to which the common channel signaling method is applied, that is, the existing public network 20 through the communication line 11. In the case of calling information requesting a service to be provided on the public network 20 by connecting to
The contract conditions and the like of the general subscriber 15 are identified and connected to the existing public network 20 through the subscriber line connection interface, that is, the communication line 12 or 13.

Therefore, the exchange 10 of the telecommunications carrier connects to the existing public network 20 by the interoffice connection interface based on the contract conditions and the like of the general subscriber 15 and the request at the time of calling. By switching whether to connect via the subscriber line connection interface, it is possible to centrally manage traffic and the like, and it is possible to omit the private branch exchange in the conventional example, so that the cost can be reduced.

FIG. 2 is an explanatory view of a main part of an embodiment of the present invention. The same reference numerals as those in FIG. 1 denote the same functional parts, 9 denotes a talkie apparatus, 22a denotes an ISDN public network, and 22b denotes an analog public network. Show. Public network 21 using common channel signaling
The ISDN public network 22a and the analog public network 22b are existing public networks.

The central control unit 5 includes a general call control processing unit 5
1, the service selection management unit 52, 7 common line connection control processing unit 53 and ISDN office line connection control processing unit 54
The main storage device 6 includes a call control processing area 61, a subscriber condition management table 62, and a service selection management table. 63.

General call control processing unit 51 of central control unit 5
Has a function that controls the entire call control process for controlling the communication path device 1. The service selection management unit 52 is activated by the general call control processing unit 51 and has a function of performing service selection processing according to each processing index. No. 7
The common line connection control processing unit 53 is activated by the general call control processing unit 51 and has a function of editing, analyzing, and transmitting / receiving a common line signal. That is, it has a function of performing control processing according to the common channel signal system. The ISDN central line connection control processing unit 54 is activated by the general call control processing unit 51 and has a function of editing, analyzing, and transmitting / receiving ISDN layer 3 messages to / from the ISDN public network 22a. The analog office line connection control processing unit 55 is activated by the general call control processing unit 51 and has a function of performing connection control processing with the analog public network 22b using analog signals. The various functions described above can be easily realized by the arithmetic processing function of the processor.

The subscriber condition management table 62 of the main storage device 6
For example, as shown in FIG. 3, it has a configuration in which contract conditions 1 and 2, terminal attributes, and transmission capabilities are stored corresponding to subscriber numbers. For example, contract condition 1 is used in an existing public network. The service provision is set as possible / not possible, the contract condition 2 is set as access / non-access to the ISDN public network 22a, the terminal attribute is set as an ISDN subscriber / analog subscriber, and the transmission capability is a voice call. / Set up audio / data call. The service selection management table 63 of the main storage device 6 includes, for example, as shown in FIG. 3, general correspondences with received numbers such as telephone numbers of called subscribers at the time of calling or dial numbers of public service requests. It has a configuration in which service types such as public subscriber connection, public service connection, and connection within its own network are stored.

FIGS. 4, 5 and 6 are flowcharts of the first embodiment of the present invention. The same reference numerals as those in FIG. 2 denote the same functions, and the general subscriber 15 calls off-hook. When the user dials the other party's telephone number or a public service request number such as an incoming call billing (A1), the general call control processing unit 51 of the central control unit 5 performs a call detection and a dial digit reception process (A2). Identify subscriber information from subscriber accommodation location information and calling information, determine the calling subscriber number,
The transmission capacity is set (A3). This transmission capability setting activates the service selection management unit 52 based on the processing index, and the service selection management unit 52 reads the transmission capability according to the calling subscriber number by referring to the subscriber condition management table 62. Set.

Then, the received numeral is analyzed (A
4), service type extraction is performed (A5). This service type extraction is performed by the service selection management unit 52 according to the received numeral.
And the service selection management unit 52 refers to the service selection management table 63 to read out service types such as a general public subscriber connection, a public service connection, and a connection in the own network corresponding to the received numeral.

The service selection management section 52 is composed of the services shown in FIGS.
The processing according to the flowchart shown in
The service selection management unit 52 performs processing according to the processing index of the input information from the general call control processing unit 51, and passes the processing result as output information to the general call control processing unit 51.
The input information includes processing index, received number, subscriber number,
The transmission capability is included, and the processing index indicates a case where transmission capability setting, service type extraction, contract condition 1 extraction, and subscriber condition extraction are included.

The service selection management unit 52 started by the general call control processing unit 51 determines the processing index (C1), and in the case of transmission capacity setting, the subscriber condition management table 62 is entered with the subscriber number of the input information. Index (C2), and set as input information transmission capability (C3). In the case of service type extraction,
The service selection management table 63 is indexed by the received number of the input information (C4), the service type is extracted (C5), and set as the service type of the output information (C6).

In the case of extracting the contract condition 1, the subscriber condition management table 62 is indexed by the subscriber number of the input information (C7), and the contract condition 1 such as whether the public service is available or not is extracted (C7).
8) Set as contract condition 1 of output information (C9).
In the case of subscriber condition extraction, the subscriber condition management table 62
Indexed by the subscriber number of the input information (C10), contract conditions 2 such as whether or not access to the ISDN public network is available, terminal attributes such as ISDN terminals or analog terminals, and transmission of voice calls, audio calls, data calls, etc. Capabilities are extracted (C11), and set as contract conditions 2 of output information, terminal attributes, and transmission capabilities (C12).

The service type is extracted in step (A5) of FIG. 4, and it is determined whether the service type is a general public subscriber connection, a public service connection, or a connection in the own network (A6). In the case of (1), it is possible to easily identify the called subscriber number because it is a subscriber number in the own network. The device 1 is controlled to call a subscriber in the own network, and a path is formed by the response of the subscriber. That is, the connection processing is performed within the same exchange.

In the case of general public subscriber connection, No. 7
Activate the common connection control processing unit 53, and 7 A connection process to the common line public network 21 is performed (A8). In this case, N
o. No. 7 common line address signal is edited by adding the calling subscriber number as calling number information, and adding the called subscriber number of the received digits as called number information. When the connection trunk device (two-way trunk 2) for the 7 common line public network 21 is captured, the edited address signal is transmitted via the signal line.

This No. In transmitting and receiving the 7 common line signal, when transmitting a signal including the generation source information, the generation source edit processing unit 56 is activated. The generation source editing processing unit 56 determines that the activation source of the generation source editing request is No. When it recognizes that it is the 7 common line connection control processing section 53, it edits and returns it to the local public network.

In the case of a public service connection, the process proceeds to step (A10) shown in FIG.
In this case, by starting the service selection management unit 52 with the calling subscriber number added to the input information, the service selection management unit 52 can execute the subscriber condition management table 62 as described above.
, The contract condition 1 is extracted. Then, the contract condition is determined (A11), and if the public service is not possible, for example, the talkie device 9 is captured, and a service restriction process for notifying the calling subscriber that the requested service cannot be provided is performed. (A12).

If the public service is available, subscriber condition extraction is performed (A13). That is, the service selection management unit 52 is activated, and the service selection management unit 52 refers to the subscriber condition management table 62 and extracts the contract condition 2, the terminal attribute, and the transmission capability based on the calling subscriber number. I do. Then, the process proceeds to the step (A9) shown in FIG.
9). For example, if the contract condition 2 indicates that the ISDN access is possible, it is determined that the ISDN station line connection processing is to be performed. If the terminal attribute is an ISDN subscriber, it is determined to be an ISDN line connection process, and if the terminal attribute is an analog subscriber, it is determined to be an analog line connection process. If the transmission capability is a voice call, it is determined to be an analog line connection process, if it is an audio call, it is determined to be an analog line connection process, and if it is a data call, it is determined to be an ISDN line connection process.

If it is determined that the connection is the analog office line connection, the analog office line connection control processing unit 55 is started, and the analog office line trunk device (the analog office line trunk 4 for connecting to the analog public network 22b) is acquired. Then, connection processing is performed by sending the called subscriber number to the analog public network 22b. If it is determined that the connection is the ISDN office line connection, the ISDN office line connection control processing unit 54 is started. IS
The DN line connection control processing unit 54 edits the calling subscriber number as the calling subaddress information in the ISDN layer 3 call setup message so as to add the received digits as the called number information, and captures the ISDN line trunk 3. Then, a call setup message is transmitted to the ISDN public network 22a.

Then, the ISDN public network 22a and the ISDN
The ISDN layer 3 message is transmitted to and received from the local line connection control processing unit 54 to connect the ISDN public network 22a and the general subscriber 15, thereby providing the ISDN public network 22a. General subscriber 1 service
5 can also be provided. When transmitting a message including generation source information when transmitting and receiving an ISDN layer 3 message, the ISDN local line connection control processing unit 54 activates the generation source editing processing unit 56. When recognizing that the ISDN office line connection control processing unit 54 has been activated, the generation source editing processing unit 56 edits the generation source information edited in the ISDN layer 3 message into the local private network.

As described above, based on the subscriber condition management table 62 and the service selection management table 63, an efficient connection process is performed in response to the request of the general subscriber 15 accommodated in the exchange of the communication carrier. It can be performed. That is, in the case of various public service connection requests such as an incoming billing service and a directory service, whether connection is possible or not is determined based on the contract condition 1. If the service is available, the ISDN public network is determined based on terminal attributes and the like. 2
2a or a process for connecting to the analog public network 22b,
In the case of a general call, a connection process to the public network 21 using the common channel signaling method can be performed.

FIGS. 9 and 10 are flowcharts according to the second embodiment of the present invention. When a call connection process is performed by the local line connection interface, a notification that a service cannot be used is received due to contract conditions or the like. In this case, a case is shown in which a transition is made to call connection processing by the subscriber line connection interface without performing recall processing.

That is, the steps (B1) to (B4) are performed by the general subscriber 15 calling off-hook and dialing the telephone number of the other party, similarly to the steps (A1) to (A4) in FIG. (B1), the general call control processing unit 51 of the central control unit 5 performs a call detection and a dial digit reception process (B2), and identifies the calling subscriber information from the subscriber accommodation position information and the calling information. , The calling subscriber number is determined, and the transmission capability is set (B3). This transmission capability setting activates the service selection management unit 52 based on the processing index, and the service selection management unit 52 refers to the subscriber condition management table 62,
The transmission capability according to the calling subscriber number is read and set, and the received digits such as the called subscriber number and public service request are analyzed (B4). Further, the service selection management unit 52 performs processing according to the processing steps described with reference to FIGS.

When the general call control processing unit 51 recognizes that the request is not a connection within its own network, but a connection request to an existing public network, the No. 7. Start the common line connection control processing unit 53. This No. 7 common line connection control processing unit 53
o, 7 A common line public network connection process is performed (B5). That is, the same processing as in step (A8) in FIG. 5 is performed, and as described above, the address signal including the calling subscriber number and the called subscriber number is transmitted to No. 7 to the common line public network 21 via a signal line. In this case, if the contract conditions with the public network 21 are satisfied, a communication path forming process between the calling subscriber and the called subscriber is performed according to the common channel signaling method.

However, if the contract conditions are not met,
From the public network 21, a disconnection signal to which reason information indicating that the service requested by the calling subscriber is unavailable or the like is added is transmitted via a signal line. This disconnection signal is received and processed by the general call control processing unit 51 of the central control unit 5, and No. No. 7 common line public network connection control processing section 53 is started, and 7 The common line public network release processing is performed (B6). Then, the process is passed to the general call control processing unit 51. The general call control processing unit 51 extracts the contract condition 1 (B7). That is, the general call control processing unit 51
Activates the service selection management unit 52, and the service selection management unit 52 generates a subscriber condition management table 62 based on the calling subscriber number.
, The contract condition 1 is extracted.

Then, the contract condition 1 is determined (B
8) If the public service such as incoming call billing or telephone number guidance is not available, the talkie device 9 is captured as a service restriction process (B9), and the calling subscriber is notified that the requested service cannot be provided. If public service is available,
A subscriber condition is extracted (B10). That is, the service selection management unit 52 is started, and the service selection management unit 52 refers to the subscriber condition management table 62 based on the calling subscriber number and extracts the contract condition 2, the terminal attribute, and the transmission capability. .

Then, the subscriber condition is determined (B11),
In the case of analog office line connection, the analog office line connection control processing unit 55 is activated to capture the office line trunk 4 for the analog public network 22b and send outgoing call information to the analog public network 22b. In the case of ISDN office line connection, ISD
Activate the N office line connection control processing unit 54 and execute the ISDN layer 3
It edits the call setup message, captures the ISDN central office trunk 3, and sends the call setup message to the ISDN public network 22a.

Further, the generation source editing processing unit 56, as in the case shown in FIG. 7 When activated by the common line connection control unit 53, the source information is edited into the local public network, and
When activated by the SDN local line connection control processing unit 54, the source information is edited into the local private network.

As described above, when connection processing to the public network 21 by the common channel signaling method is performed, the contract conditions are not met, and when a disconnection signal is received, the calling subscriber must perform a recall operation. By referring to the subscriber condition management table 62 without connecting, the connection processing to the ISDN public network 22a or the analog public network 22b can be performed.

In selecting between the ISDN public network 22a and the analog public network 22b, it is also possible to make a determination based on one of the contract condition 2, the terminal attribute, and the transmission capability of the subscriber condition management table 62. Yes, it is also possible to select the ISDN public network 22a and perform connection processing only when a plurality of conditions are satisfied. When a call is made from the general subscriber 15 accommodated in the exchange 10, connection processing is performed by the central office connection interface, and only when a disconnection signal from the public network 21 is received, the connection is switched to the subscriber line connection interface. It is also possible to do.

[0046]

As described above, according to the present invention, the existing public network 20 is connected by the inter-office connection interface and the subscriber line connection interface, and is compatible with the contract conditions of general subscribers. By performing the switching, there is an advantage that the private branch exchange can be omitted and the public service requested by the general subscriber can be provided according to the contract conditions. Therefore, since the private branch exchange can be omitted, the system cost can be reduced, and the traffic information can be centrally managed, and the exchange as a facility of a new type 1 telecommunications carrier or a new type 2 telecommunications carrier can be realized. There is an advantage that the system can be made economical.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of the present invention.

FIG. 2 is an explanatory diagram of a main part of the embodiment of the present invention.

FIG. 3 is an explanatory diagram of a subscriber condition management table and a service selection management table.

FIG. 4 is a flowchart according to the first embodiment of the present invention.

FIG. 5 is a flowchart according to the first embodiment of the present invention.

FIG. 6 is a flowchart according to the first embodiment of the present invention.

FIG. 7 is a flowchart of a service selection management unit according to the first embodiment of this invention.

FIG. 8 is a flowchart of a service selection management unit according to the first embodiment of this invention.

FIG. 9 is a flowchart according to the second embodiment of the present invention.

FIG. 10 is a flowchart according to the second embodiment of the present invention.

FIG. 11 is a schematic explanatory view of a conventional example.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Communication apparatus 2 Two-way trunk 3 Central line trunk 4 Central line trunk 5 Central control unit (CC) 6 Main storage unit (MEM) 7 Common line signal unit (CSE) 10 Switchboard 11, 12, 13 Communication line 14 Signal line 15 General subscriber 20 Existing public network 21, 22 Public network 23 Two-way trunk 24, 25 Subscriber circuit 26 Common line signaling device (CSE)

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hidenobu Inoue 4-1-1, Kamidadanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture Inside Fujitsu Limited (72) Inventor Ichiro Matsuura 4-chome, Kamiodanaka, Nakahara-ku, Kawasaki City, Kanagawa Prefecture No. 1 in Fujitsu Limited

Claims (9)

[Claims] A telecommunications carrier exchange accommodating a general subscriber is provided with a subscriber line connection interface to an existing public network and an interoffice connection interface to which a common line signaling system is applied, and a request of a calling subscriber is provided. And a step of switching between the subscriber line connection interface and the interoffice connection interface in accordance with the contract condition of the calling subscriber. 2. When the calling subscriber accommodated in the exchange of the telecommunications carrier requests a public service, one of the subscriber line connection interface and the interoffice connection interface is determined according to the contract conditions of the calling subscriber. 2. The public network connection interface switching method according to claim 1, further comprising the step of performing connection processing by switching to the public network interface. 3. An ISD according to a contract condition of the calling subscriber when switched to the subscriber line connection interface.
2. The public network interface switching method according to claim 1, further comprising the step of performing a connection process to an N public network or an analog public network. 4. When the terminal is switched to the subscriber line connection interface, an ID corresponding to the terminal attribute of the calling subscriber is set.
2. The public network connection interface switching method according to claim 1, further comprising the step of connecting to an SDN public network or an analog public network. 5. When a call is switched to the subscriber line connection interface, an I / O corresponding to the transmission capability of the calling subscriber is performed.
2. The public network connection interface switching method according to claim 1, further comprising the step of connecting to an SDN public network or an analog public network. 6. A connection process for a public network by switching a calling subscriber to the interoffice connection interface, and upon receiving a disconnection signal including reason information from the public network, a contract condition of the calling subscriber. 6. The public network connection interface switching method according to claim 1, further comprising the step of determining whether or not to perform a re-call process by switching to the subscriber line connection interface according to the following. 7. A communication carrier exchange accommodating a general subscriber and connecting to an existing public network, a central office trunk connected to the existing public network as a subscriber line connection interface, and a common line. A two-way trunk connected as an interoffice connection interface to which a signaling system is applied; a communication path device connecting the existing public network and a general subscriber via the office line trunk and the two-way trunk; A central control device for controlling the device; and a main storage device including a call control information area for storing call control processing information, wherein the main storage device manages a subscriber condition storing contract conditions corresponding to a subscriber number. And a service selection management table storing service types, wherein the central control unit, in accordance with a request of a calling subscriber, has the subscriber condition management table in the main storage device and the service Exchange, characterized in that with reference to the selected management table has a configuration that performs processing of switching the subscriber line connection interface between the interoffice connection interface. 8. The subscriber condition management table of the main storage device,
8. The exchange according to claim 7, wherein the exchange is configured to set a public service availability, an accessible public network type, a terminal attribute, and a transmission capability corresponding to the subscriber number. 9. The service selection management table in the main storage device has a configuration in which a service type of a public service connection, a general public subscriber connection, or a connection in the own network is stored in correspondence with the number of a service request. The exchange according to claim 7, wherein