KR20020010975A - Method and Device for Interlocking PABX through ATM Network - Google Patents

Abstract

PURPOSE: A private exchange system interworking method and apparatus through an ATM network are provided to connect an existing private exchange to an ATM network, use a different type of private exchange system like the same type of system, and manage it as one system. CONSTITUTION: When a subscriber of a transmitting private exchange system requests a call, a local switching unit of the transmitting private exchange system analyzes it, generates a call set-up message as a 53-byte nonstandard ATM cell, and transmits it to a central switching unit through a UTOPIA interface(S10). The central switching unit analyzes a VCI/VPI of the nonstandard ATM cell for the generated call set-up message by hardware and switches to an ATM interworking unit of a corresponding node(S11). The ATM interworking unit converts the nonstandard ATM cell for the switched call set-up message into a standard ATM cell through an ATM cell header converting unit, and transmits it to a receiving private exchange system through the ATM network(S12). The ATM interworking unit of the receiving private exchange system analyzes the standard ATM cell for the call set-up message, and transmits it to a local switching unit of the corresponding node, thereby completing a call set-up(S13).

Description

Interworking method and device for private exchange system through asynchronous transmission mode network {Method and Device for Interlocking PABX through ATM Network}

The present invention relates to a method and an apparatus for interworking with a private exchange system through an asynchronous transmission mode (hereinafter referred to as 'ATM') network. The present invention relates to a method of interworking with a private exchange system through an ATM network that can be used as a system of the same type and can be managed as a system by an interworking method using the Voice and Telephony Over ATM (TEST) technology and the device.

FIG. 1 is a conceptual diagram illustrating a configuration of interworking different types of private exchange systems using the V5.2 protocol as a conventional technology.

As shown in FIG. 1, in order to interoperate different types of private exchange systems, each private exchange system is connected to a PSTN using a V5.2 protocol that can accommodate up to 16 DS1E links. Q.SIG is used to manage and use two different private exchange systems connected to the PSTN as a single system. In order to interwork two different types of private exchange system through PSTN network, physical interface and protocol must be supported.

For the V5.2 protocol, the physical interface can accommodate up to 16 DS1E links. In addition, in order to perform various control functions for the remote subscriber, ITU-T, G.764, G.765, which are standardized communication protocols, between the local exchange 10 of the PSTN network and the systems A, B (11, 12). , ETSI ETS 300-324-1, ETSI ETS 300-347-1. The v5.2 protocol consists of system startup procedures, National PSTN protocol procedures, control protocol procedures, BCC protocol procedures, link control protocol procedures, and protection protocol procedures. In accordance with the procedural and protocol requirements for the V5.2 protocol, the V5.2 protocol provides analog dial-up, ISDN basic access, ISDN primary rate access, and other analog or digital leased lines. Support connection function. System operation and configuration management between the local exchange 10 of the PSTN network and the systems A and B (11, 12) is performed through Q.SIG. Through the interfaces and protocols described above, subscribers of System A (11) and System B (12) provide fixed services, such as PSTN, ISDN basic access, and ISDN basic rate access service, on-demand service, fixed by V5.2. Permanent line capability and permanent released line service allow system A (11) and system B (12) to be used as systems of the same type, system A (11) and system B (12) can be managed as a system.

However, V5.2 has a limitation in bandwidth that can provide only a maximum of 2.048 Mbps x 16 bands and physically cannot be used in an ATM network.

An object of the present invention is to solve the above problems, it is possible to connect the existing private exchange to the ATM network, the system of the same type to the other type of private exchange system connected to the ATM network using voice and telephone technology on ATM The present invention provides a method and apparatus for interworking with a private exchange system through an ATM network that can be used as a single system and managed by one system.

1 is a conceptual diagram illustrating a configuration of interworking different types of private exchange systems using the V5.2 protocol as a conventional technology,

2 is a conceptual diagram schematically showing a configuration for interworking between private exchange systems of different models through an ATM network according to an embodiment of the present invention.

3 is a flowchart illustrating a call setup process between private exchange systems of different models through an ATM network according to an embodiment of the present invention.

4 is a flowchart illustrating a process of transmitting a PCM voice signal between private exchange systems of different types through an ATM network according to an embodiment of the present invention.

FIG. 5 is a diagram illustrating a configuration of an interworking system of different types of private exchange systems through an ATM network according to an embodiment of the present invention.

FIG. 6 is a block diagram illustrating an internal configuration of a local switching unit of a private exchange system interworking apparatus according to an embodiment of the present invention.

7 is a block diagram illustrating an internal configuration of an ATM cell conversion switching unit of a local switching unit according to an embodiment of the present invention.

FIG. 8 is a diagram illustrating the internal configuration of an ATM interlocking unit of a private exchange system interworking apparatus according to an embodiment of the present invention.

9 is a diagram illustrating an ATM service layer that an ATM interworking unit can support as an embodiment of the present invention.

In order to achieve the above object, the private exchange system interworking method through the ATM network according to the present invention includes the steps of (a) converting the PCM voice signal to a non-standard ATM cell of the local switching unit of the transmitting private exchange system; (B) analyzing the VCI / VPI of the non-standard ATM cell converted in step (a) and switching to the ATM interworking unit of the node; (C) converting the non-standard ATM cell switched in step (b) to an ATM interworking unit by converting the non-standard ATM cell into a standard ATM cell to the receiving side private exchange system through the ATM network; (D) converting the standard ATM cell transmitted in step (c) into a non-standard ATM cell by a receiving side ATM interworking unit and transmitting it to a central switching unit; (E) analyzing, by the central switching unit, the VCI / VPI of the non-standard ATM cell transmitted in step (d) and switching to the local switching unit of the corresponding node; And converting the non-standard ATM cell transmitted to the local switching unit into a PCM voice signal in step (e).

In accordance with an aspect of the present invention, an apparatus for interoperating with a private exchange system through an ATM network includes: a local switching unit converting a subscriber's PCM voice signal into a non-standard ATM cell or a non-standard ATM cell into a PCM voice signal and transmitting the same to the subscriber; A central switching unit for switching a non-standard ATM cell from the local switching unit to the ATM interworking unit of the node or from the ATM interlocking unit to the local switching unit of the node; An ATM interworking unit converting the non-standard ATM cell received from the central switching unit into a standard ATM cell and transmitting the same through an ATM network or converting a standard ATM cell received through the ATM network into a non-standard ATM cell and transmitting the same to the central switching unit; And a central processing unit in charge of operation / management of the private exchange system.

Hereinafter, with reference to the accompanying drawings will be described in detail a preferred embodiment of the present invention.

Prior to the detailed description, terms used below are described in order to describe a method and apparatus for interworking a private exchange system via an ATM network according to the present invention.

Private Automatic Branch eXchange (PABX) is a telephone exchange system that allows all employees to share a certain number of external telephone lines used in the company and automatically connects telephones among internal users connected to the extension. to be. In the present invention, different types of private switching systems must support UNI SIG 4.0, PNNI 1.0, ITU-T Q.2931, Q.2957 of ATM Forum for transmitting voice and telephone in ATM network.

The Local Switching Module (LSM) is a device that converts a PCM voice signal of a subscriber connected to a private switching system into a nonstandard ATM cell or a nonstandard ATM cell into a PCM voice signal.

An ATM interworking module (AWM) is a device that converts a non-standard ATM cell into a standard ATM cell and transmits it through an ATM network or converts a standard ATM cell received through an ATM network into a non-standard ATM cell.

'Non-standard ATM cell' means an ATM cell determined by the private specification of the private exchange system and used only inside the private exchange system.

FIG. 2 is a conceptual diagram schematically showing a configuration for interworking between private exchange systems of different models through an ATM network according to an embodiment of the present invention.

FIG. 2 illustrates a network connection for using different types of private switching systems 20 and 21 as one system through an ATM network 22. The ATM network 22 and DS1 / DS3 / OC3 and the like are shown in FIG. Connect through the physical interface.

3 is a flowchart illustrating a call setup process between private exchange systems of different types according to an embodiment of the present invention. FIG. 3 is described with reference to the reference numerals of FIG. 2.

When there is a call setup request from the 64 Kbps single line telephone, ISDN subscriber, trunk line (CO) or leased line subscriber of the transmitting private switching system 10 to the receiving private switching system 11, the transmitting private switching system 10 The corresponding subscriber of the receiving private exchange system 11 can be called as an extension subscriber.

In response to a call request from the subscriber of the transmitting side private switching system 20, the local switching unit of the transmitting side private switching system 20 analyzes this to generate a call setup message as a non-standard ATM cell of 53 bytes, and central switching via the UTOPIA interface. Transmit to negative (S10).

The central switching unit analyzes VCI / VPI of the non-standard ATM cell in hardware with respect to the generated call establishment message and switches to the ATM interworking unit of the corresponding node (S11).

The ATM interworking unit converts the non-standard ATM cell for the switched call establishment message into a standard ATM cell through the ATM cell header converting unit and transmits the non-standard ATM cell to the receiving side private exchange system 21 through the ATM network 22 (S12).

The ATM interworking unit of the receiving side private exchange system 21 analyzes the standard ATM cell for the transmitted call establishment message and transmits it to the local switching unit of the corresponding node, thereby completing the call setup (S13).

4 is a flowchart illustrating a process of transmitting a PCM voice signal between private exchange systems of different types through an ATM network according to an embodiment of the present invention.

The transmitting local switching unit converts the 64 Kbps PCM voice signal of the line user received through the call set up by the call request of the private switching system into a non-standard ATM cell of the transmitting private switching system and transmits it to the central switching unit (S20).

The transmitting central switching unit analyzes the VCI / VPI of the non-standard ATM cell converted by the local switching unit and switches to the ATM interworking unit of the corresponding node (S21).

The transmitting ATM interworking unit converts the switched non-standard ATM cell into a standard ATM cell through the ATM cell header converting unit and transmits the converted non-standard ATM cell to the receiving side private exchange system through the ATM network (S22). In order to use as a system through ATM network, ATM interworking unit is connected to ATM network through physical interface such as DS1 / DS3 / OC3.

The receiving ATM interworking unit converts the received standard ATM cell into a non-standard ATM cell of the receiving private exchange system through the ATM cell header converting unit and transmits the converted standard ATM cell to the central switching unit (S23). In order to use as a system through the ATM network, the ATM interworking unit is connected to the ATM network through a physical interface such as DS1 / DS3 / OC3.

The receiving central switching unit analyzes the VCI / VPI of the transmitted non-standard ATM cell and switches to the local switching unit of the corresponding node (S24).

The non-standard ATM cell switched to the receiving local switching unit is converted into a 64 Kbps PCM voice signal and transmitted to the receiving subscriber through a call set by the subscriber's call request (S25).

FIG. 5 is a diagram illustrating the configuration of an interworking system of a different type of private exchange system through an ATM network according to an embodiment of the present invention.

The local switching unit 30 converts the subscriber's PCM voice signal into a non-standard ATM cell and transmits it to the central switching unit 40 or converts the non-standard ATM cell transmitted by the central switching unit 40 into a PCM voice signal and transmits it to the subscriber. do. The local switching unit 30 supports N 64 Kbps lines. The internal configuration of the local switching unit is shown in FIG.

The central switching unit 40 switches the non-standard ATM cell converted by the local switching unit 30 from the local switching unit 30 to the ATM interworking unit 50 of the node or the non-standard ATM converted by the ATM interlocking unit 50. The ATM cell is switched to the local switching unit 30 of the node. The central switching unit 40 is connected to the local switching unit 30, the ATM interworking unit 50, and the central processing unit 60 by an unshielded twisted pair (UTP) 5 or optical fiber of 155 Mbps.

The ATM interworking unit 50 converts the non-standard ATM cell received from the central switching unit 40 into a standard ATM cell and transmits it through the ATM network, or converts the standard ATM cell received through the ATM network into a non-standard ATM cell. Transmit to 40. The internal configuration of the ATM interlock 50 is shown in FIG.

The central processing unit 60 is in charge of the operation / management of the private exchange system.

FIG. 6 is a diagram illustrating an internal configuration of a local switching unit of a private exchange system interworking apparatus according to an embodiment of the present invention.

The ATM cell conversion switching unit 31 converts the 64 Kbps PCM voice signal received from the subscriber into a non-standard ATM cell and transmits it to the central switching unit through the UTOPIA interface 34 or from the central switching unit through the UTOPIA interface 34. The received non-standard ATM cell is converted into 64 Kbps PCM voice signal and transmitted to the subscriber.

The DTMF receiver 32 detects the telephone tone of the subscriber transmitted by the ATM cell conversion switching unit 31 to grasp the number entered by the subscriber.

The bus controller 33 controls bus transmission and reception between the local switching unit and the external device.

The UTOPIA interface 34 provides a physical interface for nonstandard ATM cell transmission between the ATM cell conversion switching unit 31 and the central switching unit.

The control unit 35 controls the ATM cell conversion switching unit 31, the DTMF receiving unit 32, the bus control unit 33, and the UTOPIA interface 34 in the local switching unit.

The duplication control unit 36 transmits and receives a duplication signal for synchronous control between the local switching unit and other components of the private exchange system interworking device.

The clock generator 37 generates a clock necessary for the ATM cell conversion switching unit 31, the DTMF receiving unit 32, the bus control unit 33, the UTOPIA interface 34, the control unit 35, and the redundancy control unit 36. .

7 is a block diagram illustrating an internal configuration of an ATM cell conversion switch of a local switching unit according to an embodiment of the present invention.

The ATM cell converter 311 converts a 64 Kbps PCM voice signal into a nonstandard ATM cell or a nonstandard ATM cell into a 64 Kbps PCM voice signal.

The transmitting cell buffer 312 temporarily stores the non-standard ATM cell received from the ATM cell converter 311 to transmit the non-standard ATM cell.

The receiving cell buffer 313 temporarily stores the nonstandard ATM cell to be transmitted to the ATM cell converter 311 to receive the nonstandard ATM cell.

The cell transceiver 314 reads a nonstandard ATM cell from the transmit cell buffer 312 or stores a nonstandard ATM cell in the receive cell buffer 313 for cell transmission and reception.

The UTOPIA interface 315 provides a physical interface for non-standard ATM cell transmission between the cell transceiver 314 and an external device.

The CPU interface 316 is a CPU for controlling the ATM cell converter 311, the transmit cell buffer 312, the receive cell buffer 313, the cell transceiver 314, and the UTOPIA interface 315, and the respective components. It provides a physical interface to control wealth.

FIG. 8 is a block diagram illustrating an internal configuration of an ATM interlock unit of a private exchange system interworking device according to an embodiment of the present invention. Unmarked ATM CAM is a CAM memory. In addition to simple standard ATM cell conversion, ATM CAM has a built-in call processing program that manages which incoming call should be sent to the local switching part of the nodes of the private switching system.

The UTP5 / ATM SONET framer unit 51 is composed of a UTP5 unit and an ATM SONET framer unit for transmitting and receiving non-standard ATM cells between the ATM interworking unit and the central switching unit.

The Optic / ATM SONET framer unit 52 is composed of an Optic unit and an ATM SONET framer unit for transmitting and receiving standard ATM cells between the ATM interworking unit and the ATM network.

The ATM header converting section 53 converts a nonstandard ATM cell in the private switching system into a standard ATM cell or a standard ATM cell into a nonstandard ATM cell.

The nonstandard ATM cell buffer 54 temporarily stores the nonstandard ATM cell received from the ATM cell header converter 53 to convert the nonstandard ATM cell into a standard ATM cell.

The standard ATM cell buffer 55 temporarily stores a standard ATM cell to be sent to the ATM cell header converter 53 to convert a standard ATM cell into a non-standard ATM cell.

The CPU interface 56 includes the UTP5 / ATM SONET framer unit 51, the Optic / ATM SONET framer unit 52, the ATM header converter 53, the non-standard ATM cell buffer 54, and the standard ATM cell buffer 55. It provides a CPU for controlling and a physical interface to control each component.

9 is a diagram illustrating an ATM service layer that an ATM interworking unit can support as an embodiment of the present invention.

The private exchange system interworking method through the ATM network and the system according to the present invention supports the physical layer, ATM layer, AAL layer, service layer.

As described above, according to the method and apparatus for interworking with a private exchange system through an ATM network according to the present invention, an existing private exchange can be connected to an ATM network. In addition, different types of private switching systems connected to the ATM network may be used as the same type of system, and managed as one system. In addition, it can provide a wider bandwidth than the interlocking by the Q.SIG of the existing PSTN, it is possible to implement a high-capacity interlocking and high-speed service by expanding the capacity of the private exchange system.

Claims (6)

Converting, by the local switching unit of the transmitting private switching system, the PCM voice signal into a nonstandard ATM cell; (B) analyzing the VCI / VPI of the non-standard ATM cell converted in step (a) and switching to the ATM interworking unit of the node; (C) converting the non-standard ATM cell switched in step (b) to an ATM interworking unit by converting the non-standard ATM cell into a standard ATM cell to the receiving side private exchange system through the ATM network; (D) converting the standard ATM cell transmitted in step (c) into a non-standard ATM cell by a receiving side ATM interworking unit and transmitting it to a central switching unit; (E) analyzing, by the central switching unit, the VCI / VPI of the non-standard ATM cell transmitted in step (d) and switching to the local switching unit of the corresponding node; And And (f) converting the non-standard ATM cell transmitted to the local switching unit into a PCM voice signal in step (e). The method of claim 1, Before step (a), (F) generating, by the subscriber's call request, the local switching unit of the transmitting private switching system to a non-standard ATM cell; (G) analyzing, by the central switching unit, the VCI / VPI of the call establishment message generated in the step (f) and switching to the ATM interworking unit of the corresponding node; (H) converting the call setup message switched to the ATM interworking unit into a standard ATM cell in step (g) and transmitting it to a receiving side private exchange system through an ATM network; And And (i) analyzing, by the ATM interworking unit, the call establishment message transmitted to the receiving side private exchange system in step (h) and transmitting it to the local switching unit of the corresponding node. How to link. A local switching unit converting the subscriber's PCM voice signal into a non-standard ATM cell or converting the non-standard ATM cell into a PCM voice signal and transmitting the same to the subscriber; A central switching unit for switching a non-standard ATM cell from the local switching unit to the ATM interworking unit of the node or from the ATM interlocking unit to the local switching unit of the node; An ATM interworking unit converting the non-standard ATM cell received from the central switching unit into a standard ATM cell and transmitting the same through an ATM network or converting a standard ATM cell received through the ATM network into a non-standard ATM cell and transmitting the same to the central switching unit; And A private exchange system interworking apparatus through an ATM network, characterized in that it comprises a central processing unit for the operation / management inside the private exchange system. The method of claim 3, The local switching unit, An ATM cell conversion switching unit converting the PCM voice signal received from the subscriber into a non-standard ATM cell or converting the non-standard ATM cell into a PCM voice signal and transmitting the same to the subscriber; A DTMF receiver for detecting a telephone tone of a subscriber transmitted by the ATM cell conversion switching unit; A bus controller for controlling bus transmission and reception between the local switching unit and an external device; A UTOPIA interface unit providing a physical interface for non-standard ATM cell transmission between the ATM cell conversion switching unit and the central switching unit; A control unit for controlling the ATM cell conversion switching unit, a DTMF receiving unit, a bus control unit, and a UTOPIA interface; Redundancy control unit for transmitting and receiving a redundant signal for control; And And an ATM cell conversion switching unit, a DTMF receiving unit, a bus control unit, a UTOPIA interface unit, a control unit, and a clock generation unit for generating a clock required for the redundancy control unit. The method of claim 4, wherein ATM cell conversion switching unit, An ATM cell converter for converting a PCM voice signal into a nonstandard ATM cell or a nonstandard ATM cell into a PCM voice signal; A transmission cell buffer for temporarily storing the non-standard ATM cell received from the ATM cell converter for transmitting a non-standard ATM cell; A receiving cell buffer for temporarily storing a non-standard ATM cell for transmission to the ATM cell converter for receiving a non-standard ATM cell; A cell transceiver for reading a nonstandard ATM cell from the transmitting cell buffer or storing a nonstandard cell in the receiving cell buffer for transmitting and receiving a cell; A UTOPIA interface unit providing a physical interface for non-standard ATM cell transmission between the cell transceiver unit and an external device; And And a CPU interface unit for providing a physical interface for controlling the cell conversion unit, the transmit cell buffer, the receive cell buffer, the cell transceiver unit, and the UTOPIA interface unit. The method of claim 3, The ATM linkage unit, A UTP5 / ATM SONET framer unit for transmitting and receiving non-standard ATM cells between the ATM interworking unit and the central switching unit; Optic / ATM SONET framer unit for transmitting and receiving a standard ATM cell between the ATM interworking unit and the ATM network; An ATM header conversion unit for converting a non-standard ATM cell in a private switching system into a standard ATM cell or converting a standard ATM cell into a non-standard ATM cell; A non-standard ATM cell buffer for temporarily storing the non-standard ATM cell received from the ATM cell header converter to convert the non-standard ATM cell into a standard ATM cell; A standard ATM cell buffer for temporarily storing a standard ATM cell for transmission to the ATM cell header converter to convert a standard ATM cell into a non-standard ATM cell; And The UTP5 / ATM SONET framer unit, Optic / ATM SONET framer unit, ATM header conversion unit, non-standard ATM cell buffer and the CPU interface interface for controlling the standard ATM cell buffer, characterized in that the private exchange system interworking over ATM network Device.