JPH0637902A - Private branch exchange - Google Patents

Abstract

PURPOSE:To easily prevent an illegal access from the third unrelated person by the 'public-private-public' connection of a private line with public networks at the both sides. CONSTITUTION:A group number identifying part 31 receives the identification number of a calling terminal transmitted from the public network at a calling side, collates the identification number to data preliminarily registered in a calling ID expanding table 41, and identifies the presence or absence of a group number corresponding to the identification number. A pass word identifying part 32 receives a pass word equivalent to the telephone number of an incoming terminal inputted from the calling terminal, collates the pass word to the pass word preliminarily registered by each group number in a pass word expanding table 42, and identifies whether or not they are matched. A connection regulation control part 33 reads the telephone number of the incoming terminal based on the pass word only when the matching of the pass word is identified by the pass word identifying part 32, and transmits it to a private branch exchange at an incoming side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stored program controlled private branch exchange.

[0002]

2. Description of the Related Art Conventionally, a private branch exchange connected to a calling public network is connected to a called private branch exchange via a leased line, and the called private branch exchange is connected to the called public network. In the so-called "public-dedicated-public" connection, mutual connection is possible for data communication such as facsimile and voice communication is excluded. In this case, since there are two types of attributes, "data" and "voice", a "public-dedicated-public" connection is implemented by means of dividing the line or dividing the access code.

However, in recent years, even in voice communication, "public-
It is in a communication environment that promotes the construction of an advanced information and communication system by allowing "special-public" connection conditionally. Especially recently
Only for international leased lines set up between specific countries, it is possible to connect to the domestic public telephone network on each country side. However, it is a condition that the private branch exchange (PBX) and other terminal equipment connected to both ends of the international leased line do not mediate communication of a third party.

On the other hand, when a so-called "public-dedicated-public" connection is performed, the terminal originating in the public network once dials the PBX or other terminal equipment to establish a communication state, and then gives the originating terminal by a PB signal. Dial the password provided,
Security checks are done. Next, in order to dial the called party's telephone number, it is necessary to dial more than 24 digits.

[0005]

As described above, in the conventional private branch exchange, when a "public-dedicated-public" connection is made, the caller needs to operate a dial of, for example, 24 digits or more, which is difficult to use. Not only that, but if someone else steals your password, it will be sent anywhere.

[0006]

The private branch exchange of the present invention comprises:
A first private branch exchange connected to the first public network on the calling side is connected to a second private branch exchange on the called side via a leased line;
In the switching system in which the second private branch exchange is connected to the called second public network, the first private branch exchange is:
First identification means for receiving the identification number of the calling terminal transmitted from the first public network, collating it with pre-registered data and identifying the presence or absence of a group number corresponding to this identification number; Second identification means for receiving a password corresponding to the telephone number of the destination terminal input from the terminal, collating it with a password registered in advance for each of the group numbers, and identifying whether or not they match, Only when the password is matched by the second identifying means, the control means for reading out the telephone number of the destination terminal based on the password and sending it to the second private branch exchange is provided.

[0007]

The present invention will be described below with reference to the drawings.

FIG. 1A is a sequence diagram showing the connection with the public network on both sides of the leased line. The calling terminal in the public network receives the call at the private branch exchange PBX-A and is in communication with the calling terminal in the public network. When the calling terminal in the public network dials the password for the required number of digits (generally 4 to 5 digits) by the PB signal, the private branch exchange PBX-A sets the received password to the registered regular callee number. The destination number information is converted and sent to the other private branch exchange PBX-B connected by a dedicated line. The transmission method is based on the known individual line signal system or common line signal system.

Although not shown in this embodiment, it is also possible to dial a personal identification number (ID code) of 1 to 10 digits before the password to the terminal originating in the public network. The private branch exchange PBX-B sends the called number received from the PBX-A to the public network accommodating the PBX-B to establish a so-called public-dedicated-public connection.

Next, the operation of the storage program controlled private branch exchange PBX in the connection sequence of FIG.
A detailed description will be given based on (b). FIG. 1 (b) is a block diagram of a stored program control type private branch exchange of the present invention. 1 is a trunk line trunk, 2 is an incoming call register, 3 is a central control unit, 4 is a storage unit, 5 is a switch link, and 6 Indicates a leased line trunk, and 7 indicates a sender circuit. Central controller 3
Is a group number identification unit 31 and a password identification unit 32.
And the connection regulation control unit 33, the storage device 4
The D expansion table 41 and the password expansion table 42 are provided.

When an incoming call arrives from a calling terminal in the public network, the incoming call is displayed on the trunk line trunk 1, and at the same time, the telephone number (called the calling ID) of the calling terminal in the public network is sent. The central control device 3 receives this, expands the calling ID registered in the calling ID expansion table 41 of the storage device 4, and outputs the group No. corresponding to the received calling ID. Is read by the group number identification unit 31. Here, in the calling ID expansion table 41, the group number. If is not registered or the expansion table does not exist, the connection regulation control unit 33 makes a connection such as an announcement and notifies the public network internal terminal that the connection cannot be made.

Next, from the calling ID expansion table 41, the group number. Read, the incoming call register 2 and the trunk line trunk 1
Are connected by a switch link 5, and then a preparation for receiving a password corresponding to the telephone number of the destination terminal is made. And
The terminal originating in the public network dials the password by the PB signal. The password identification unit 32 of the central control device 3 develops the password registered in the password development table 42 of the storage device 4, and the connection regulation control unit 33 reads out the destination telephone number based on this. If the destination telephone number is not registered or the password expansion table does not exist, the connection regulation control unit 33 notifies the terminal originating in the public network by a busy tone, a regulation sound, an announcement, or the like. When the destination telephone number is read, the telephone number information is sent to the leased line trunk 6 by the sender circuit 7. The calling ID expansion table 41 and the password expansion table 42 will be described in detail later.

The exchange of the calling ID between the public network and the private branch exchange PBX will be described below with reference to FIGS. 2 (a) and 2 (b). FIG. 2A is a sequence diagram in which the calling ID is notified by the public network and the private branch exchange PBX. In the public network, the private branch exchange PBX is particularly ISDN (Integrated Service).
ces Digital Network). Further, FIG. 2B shows a system in which the calling ID is subscribed to the analog network of the public network. The calling ID is notified to the private branch exchange PBX as a "SET UP" signal in FIG. 2A and as an "information" in FIG. 2B by a PB signal or the like. The subsequent processing is a known sequence and will not be described.

Next, the above-mentioned calling ID expansion table and password expansion table will be described. FIG. 3 is the same as FIG.
The calling ID notified by the means of (a) and (b) is expanded and the group number. It shows the registration means divided into.
In FIG. 3, the calling ID is set for each route (RT) of the incoming line group of the public network.
Is expanded in single-digit units and the last digit is the group number. It has a configuration that recognizes. With the incoming line group RT, the incoming line group can be divided into units such as a first-class telecommunications carrier unit, an ISDN network, an analog network, etc., and the calling ID can be expanded in units of line group.

The incoming line group can be mounted from 1 to 255, the memory is provided from 0 to 255, and each line group is composed of 3 bytes. One of the three bytes is used to identify the presence / absence of the expansion table and the end of the table. That is, the first byte is "0"
1 is the expansion table, "02" is the end of the table,
“00” indicates that there is no expansion table. The remaining 2 bytes indicate the address for the next table expansion table.

Next, the next table expansion table is read from the table expanded for each incoming line group RT, and the address table is read as the first digit Digit Code (DC).
Index with 1. This table has the same structure as the table of the incoming line group RT, and has 16 digits corresponding to 0 to 15 every 3 bytes in the number information unit of the calling ID, that is, 48 bytes. Of the 3-byte configuration, 1 byte is for table expansion identification, and 2 bytes indicate the address for the next table expansion. Here, "0", "*", and "#" of the dialed numbers are expansion tables DC, respectively.
10, 11, and 12 are shown. Similarly, the second digit of the calling ID is expanded to the nth digit. In the table indexed by the last digit DCn, "02" indicating the end of the expansion at the first byte and the remaining 2 bytes from 1 to 255 Group No. Is shown.

In FIG. 4, the group No. read from FIG.
And a registration diagram for converting the received password into a legitimate destination number. In FIG. 4, the group No. read in FIG. The password dialed by the calling terminal in the public network is expanded in units as in the case of FIG. 3, and for example, when the final table is determined by expanding the n digits, a regular destination number of up to 24 digits is registered. As in the case of FIG. 3, the configuration of FIG. 4 shows the presence / absence of the expansion table in the first 1st byte of 3 bytes and the next table address in the remaining 2 bytes. Group No. The first table TN to be indexed with is provided with 256 groups in memory, but 0 group is unused.

Further, each of the tables DC1 to DCn-1 from the first digit to the (n-1) th digit of the password has a 48-byte structure. In the last digit DCn of the password expansion, the end of the table is shown in the first byte and the called number is registered in the remaining 12 bytes. The destination number can be registered for 24 digits because 2 digits are registered for 1 byte. or,
The destination number is registered in right bits every 4 bits. The calling ID expansion table and the password expansion table are stored in the private branch exchange PBX by the maintenance console
Register in advance.

FIG. 5 shows an example of a connection to the public network on both sides of the private line, that is, a so-called "public-dedicated-public" connection, in which terminals C1 and C2 originating from any public network are connected via the private line. 3 shows a connection form with any other destination terminals C3 and C4 in the public network. FIG. 5 shows a case where incoming calls from C1 to C3 and C2 to C4 are enabled and incoming calls from C1 to C4 and C2 to C3 are restricted, that is, communication mediation of a third party is prevented. C1 and C2 are group numbers. Are set to 1 and 2, and the calling IDs of C1 and C2 are registered in the memory shown in FIG. On the other hand, the group No. C3 and C for 1 and 2 respectively
The password corresponding to 4 is registered in the memory shown in FIG. That is, the group number. C4 in 1 and group N
o. Since C3 is not registered in 2, C1 becomes C4,
Also, C2 cannot be connected to C3. That is, the group number. Only those with registered destinations can be connected each time.

[0020]

As described above, according to the present invention, both sides of the leased line are connected to the public network, that is, the so-called "public-line".
In the "Private-Public" connection, it is possible to prevent unauthorized access from an unrelated third party by using both the password and the called number economically, reliably, and with a shorter dial.

[Brief description of drawings]

FIG. 1A is a sequence diagram showing a connection with a public network on both sides of a leased line according to an embodiment of the present invention.
FIG. 1B is a block diagram of a storage program controlled private branch exchange according to an embodiment of the present invention.

FIG. 2A is a sequence diagram when receiving a calling ID when a private branch exchange belongs to ISDN. (B) is a sequence diagram when receiving a calling ID when belonging to an analog network.

FIG. 3 shows the group number from the telephone number of the terminal originating in the public network.
Is a registration diagram for reading out the.

4 is a group No. read out from FIG. FIG. 7 is a registration diagram for converting a password dialed by a terminal originating from within the public network into a regular telephone number of a called party within the public network.

FIG. 5 is a diagram showing a form of “public-dedicated-public” connection.

[Explanation of symbols]

 1 office line trunk 2 incoming call register 3 central control unit 4 storage device 5 switch link 6 leased line trunk 7 sender circuit 31 group number identification unit 32 password identification unit 33 connection regulation control unit 41 outgoing ID expansion table 42 password expansion table

Claims (1)

[Claims] 1. A first connected to a first public network of a calling side
In the switching system, the private branch exchange is connected to a second private branch exchange on the called side through a dedicated line, and the second private branch exchange is connected to a second public network on the called side. The exchange receives the identification number of the calling terminal transmitted from the first public network, collates it with pre-registered data, and identifies the presence or absence of a group number corresponding to this identification number. A second identification means for receiving a password corresponding to the telephone number of the called terminal input from the calling terminal, collating the password with a pre-registered password for each group number, and identifying whether or not they match A private branch exchange comprising: a control unit that reads out the telephone number of the destination terminal based on the password and sends the telephone number to the second private branch exchange only when the password is matched by the second identifying unit. Machine.