KR100382354B1 - Apparatus and Method for ATM Interfacing in PSTN - Google Patents

Abstract

The present invention relates to an ATM matching device and method of a PSTN for matching with an ATM network by replacing a physical layer processing module according to a matching frequency.

Conventionally, since both the physical layer processing unit and the ATM layer processing unit exist on one board, the matching frequency is changed, and when it is necessary to replace the ATM matching device that can accommodate the frequency, it can be commonly used regardless of frequency. ATM layer processing unit also has a problem that must be replaced. In addition, the ATM matching device individually designed according to the matching frequency is also developed separately, there is a problem that the ATM layer processing unit must be developed together when the development of the physical layer processing unit is required.

The present invention can accommodate all frequencies by configuring the physical layer processing module and the ATM layer processing module in independent forms and replacing only the physical layer processing module according to the matching frequency. In addition, since only the physical layer processing module is developed, the development period can be shortened and the development cost can be reduced.

Description

Apparatus and Method for ATM Interfacing in PSTN}

The present invention relates to an ATM matching apparatus and method of the PSTN, and more particularly, to an ATM matching apparatus and method of the PSTN to match the ATM network by replacing the physical layer processing module according to the matching frequency.

In general, Asynchronous Transfer Mode (ATM) is a transmission / switching technology that is the core of B-ISDN. A Public Switched Telephone Network (PSTN) is provided with an ATM matching device for matching with an ATM network. Layer processing and ATM layer processing are performed.

The frequencies matched by the above-described ATM matching device are different from DS (Digital Signal level) -3 (44.736MHz) frequency, STM (Synchronous Transfer Mode) -1 (155.52MHz) frequency, and STM-4 (622.08MHz) frequency. In the case of conventional ATM matching devices, each ATM is individually designed to accommodate each frequency being matched.

That is, when the matching frequency is DS-3, the ATM matching device includes one connector 11, a transformer 13, and a line matching unit (1) on one board as shown in FIG. Line Interface (15), a UNI Networker (User Network Interface Framer) 17, and an ATM Cell Processor (ATM Cell Processor) 19 is provided.

In such a configuration, the connector 11 physically connects the coaxial cable, and mainly uses a BNC (British National Connector) connector.

The transformer 13 converts the voltage of the AC power received through the connector 11 into the voltage of the power used in the ATM matching device.

The line matching unit 15 amplifies and converts the signals received through the coaxial cable so that the UNI framer 17 can receive them, and transmits the signals received from the UNI framer 17 through the coaxial cable. Convert it.

The UNI framer 17 processes the signal received from the line matching unit 15 and transmits the information to the ATM cell processing unit 19 through the Universal Test and Operation PHY Interface for ATM (UTOPIA) interface, and the ATM through the UTOPIA interface. Where the information received from the cell processing unit 19 is a signal combination to be processed by the line matching unit 15, the signal received from the line matching unit 15 is encoded, and then the encoded serial data is converted into parallel data. Then, the converted parallel data is converted into a frame, and the frame is converted so that the converted frame can be processed by the ATM cell processing unit 19. After mapping the ATM cell received from the ATM cell processor 19 to the payload of the frame, the ATM cell is converted into parallel data, and the converted parallel data is converted into serial data and decoded.

The ATM cell processing unit 19 extracts the ATM cell from the information received from the UNI framer 17 through the UTOPIA interface, and then adds the route selection information in the system and changes the VPI / VCI of the ATM cell header. It performs a function to be processed and delivers it to the AAL layer processing unit (not shown).

On the other hand, when the matching frequency is STM-1, the ATM matching device includes a UTP (Unshielded Twisted Pair Wire) 5 cable / optical cable connection part 21 and a UNI framer 23 as shown in FIG. 2. ) And an ATM cell processing unit 25.

In such a configuration, the UTP5 cable / optical cable connection portion 21 physically connects the UTP5 cable / optical cable and, when connected with the optical cable, converts the optical signal transmitted through the optical cable into an electrical signal.

The UNI framer 23 is matched with UTP5 cable / optical cable connection 21 and PECL (Pseudo / Positive Emitter Coupled Logic) to process signals received from UTP5 cable / optical cable connection 21 to ATM through UTOPIA interface. It transfers the information to the cell processing unit 25, and the signal combination that the information received from the ATM cell processing unit 25 through the UTOPIA interface to be processed by the UTP5 cable / optical cable connection unit 21, the UTP5 cable / optical cable After recovering the lost and destroyed signal from the signal (data / clock) received from the connecting unit 21, converting serial data into parallel data, converting the converted parallel data into a frame, and adding an overhead After that, it transfers to the ATM cell processing unit 25. After mapping the ATM cell received from the ATM cell processor 25 to the payload of the frame, the ATM cell is converted into parallel data, and the converted parallel data is converted into serial data and decoded.

The ATM cell processing unit 25 extracts an ATM cell from the information received from the UNI framer 23 through the UTOPIA interface, and then adds the path selection information in the system and changes the VPI / VCI of the ATM cell header. It performs a function to be processed and delivers it to the AAL layer processing unit (not shown).

On the other hand, when the matching frequency is STM-4, the ATM matching device connects the optical cable connection unit 31, the UNI framer 33, and the ATM cell processing unit 35 to one board as shown in FIG. In the case where the matching frequency is STM-1, since it has a structure similar to that of an ATM matching device, a detailed description thereof will be omitted.

As described above, the conventional ATM matching device is individually designed according to the matching frequency, and the physical layer processing unit and the ATM layer processing unit are co-located and coexist in a single board. As described above, the physical layer processing unit may have a different structure according to the matching frequency, but the ATM layer processing unit may have the same structure regardless of the matching frequency.

However, since both the physical layer processing unit and the ATM layer processing unit exist on one board, the matching frequency is different, and when it is necessary to replace the ATM matching device that can accommodate the frequency, it can be used in common regardless of the frequency. ATM layer processing unit also has a problem that must be replaced.

In addition, the ATM matching device individually designed according to the matching frequency is also developed separately, there is a problem that the ATM layer processing unit must be developed together when the development of the physical layer processing unit is required.

The present invention has been made to solve the above-described problem, so that the physical layer processing unit and the ATM layer processing unit each composed of a separate type of module, and replaces only the physical layer processing module according to the matching frequency to accommodate the corresponding frequency An object of the present invention is to provide an ATM matching device and method of the PSTN.

1 to 3 is a view showing the configuration of a conventional ATM matching device.

4 is a diagram showing the configuration of an ATM matching device according to the present invention;

5 illustrates a configuration of a physical layer processing module when the matched frequency is DS-3.

6 illustrates a configuration of a physical layer processing module when the matched frequency is STM-1.

FIG. 7 illustrates the configuration of a physical layer processing module when the matched frequency is STM-4. FIG.

8 is a flowchart illustrating an ATM matching method of a PSTN according to the present invention.

*** Explanation of symbols for the main parts of the drawing ***

100, 110, 120, 130. physical layer processing module,

109, 119, 129, 139. Division signal generator,

111.connectors, 113.transformers,

115. Line matching, 117, 123, 133. UNI framer,

121.UTP5 cable / optical cable connection, 131. Optical cable connection,

200. ATM cell processing module, 300. ATM matching device

The ATM matching device of the PSTN according to the present invention for achieving the above object is a physical layer processing module that is individually designed and replaced according to the matching frequency; And an ATM cell processing module for initializing and controlling each of the physical layer processing modules according to the physical layer processing module.

Here, each physical layer processing module stores an identification value for distinguishing a type of the physical layer processing module, and when the physical layer processing module is mounted, generates a classification signal according to the identification value to process the ATM cell. Characterized in that it comprises a division signal generator for applying to the module.

The ATM cell processing module includes: a DS-3 initialization unit for initializing a physical layer processing module that matches a DS-3 frequency; An STM-1 initializer for initializing the physical layer processing module that matches the STM-1 frequency; An STM-4 initialization unit for initializing a physical layer processing module that matches an STM-4 frequency; And a controller configured to initialize the physical layer processing module by controlling any one of the DS-3 initializer, the STM-1 initializer, and the STM-4 initializer based on the division signal received from the division signal generator. It is characterized by.

Each of the physical layer processing module and the ATM cell processing module may include: a division signal bus used to transmit a division signal for distinguishing a type of the mounted physical layer processing module; A UTOPIA interface bus for transmitting transmit enable signals, transmit / receive data, transmit / receive frame clocks, and transmit / receive cell start signals; And an address bus and a data bus used to initialize and control the mounted physical layer processing module.

The ATM cell processing module may be designed to receive and operate the highest frequency among frequencies matched with each physical layer processing module.

On the other hand, the ATM matching method of the PSTN according to the present invention, the process of receiving a division signal from the physical layer processing module mounted; The type of the physical layer processing module is installed based on the received classification signal, and among the DS-3 initializer, STM-1 initializer, and STM-4 initializer according to the type of the separated physical layer process module. Initializing a framer of the mounted physical layer processing module by controlling any one; And processing an ATM cell received from the initialized physical layer processing module through a UTOPIA interface.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to ATM matching apparatus and method of the PSTN according to an embodiment of the present invention.

4 is a diagram illustrating a configuration of an ATM matching device of a PSTN according to the present invention, which performs a physical layer processing function, and is physically replaced by a physical layer processing module 100 and a physical layer processing module mounted according to a matching frequency. Initialize and control the physical layer processing module 100 according to 100), extract an ATM cell from a frame received from the physical layer processing module 100 through a UTOPIA interface, add path selection information in the system, and add an ATM cell header. It is provided with an ATM cell processing module 200 for performing a function that must be processed in the ATM layer, such as changing the VPI / VCI of.

In this configuration, the physical layer processing module 100 includes a division signal generator 109 for generating a division signal for distinguishing itself, and the division signal generator 109 is shown in Table 1 as shown in Table 1 below. In addition, the physical layer processing module 100 stores only identification values separately set according to whether the module matches the DS-3 frequency, the STM-1 frequency, or the STM-4 frequency. When the processing module 100 is mounted, a TTL {High (1), Low (0)} signal is generated and applied to the ATM cell processing module 200 based on the identification value. For example, the division signal generator 109 included in the physical layer processing module matched with the DS-3 frequency may identify identification values B1 and B0 indicating that the physical layer processing module 100 is a module matched with the DS-3 frequency. 0 and 0) are stored, and when the physical layer processing module 100 is mounted on the backboard, a TTL signal is generated based on the identification value and applied to the ATM cell processing module 200.

DS-3 STM-1 STM-4 B1 0 0 One B0 0 One 0

Meanwhile, the ATM cell processing module 200 includes a control unit 210, a DS-3 initialization unit 220, an STM-1 initialization unit 230, and an STM-4 initialization unit 240. The controller 210 classifies the type of the physical layer processing module 100 based on the division signal received from the physical layer processing module 100, and initializes DS-3 according to the type of the divided physical layer processing module 100. The physical layer processing module 100 is initialized by controlling any one of the unit 220, the STM-1 initializer 230, and the STM-4 initializer 240. That is, when the physical layer processing module 100 divided based on the division signal received from the physical layer processing module 100 is a module matching the DS-3 frequency, the DS-3 initialization unit 220 is controlled to control the physical. Initialize the layer processing module 100. Here, the DS-3 initialization unit 220 for initializing the physical layer processing module 100 under the control of the controller 210 allows the physical layer processing module 100 to transmit and receive a frame by matching the DS-3 frequency. The register of the UNI framer included in the physical layer processing module 100 is set to a specific value by using an address bus and a data bus.

As described above, the ATM cell processing module 200 needs to be able to process all frames received from the physical layer processing module 100 that is replaced and mounted according to the matching frequency, and thus operates by accommodating the highest STM-4 frequency. This should be designed to be possible.

In addition, the physical layer processing module 100 and the ATM cell processing module 200 are basically matched by the UTOPIA interface, and each physical layer processing module 100 is matched with the ATM cell processing module 200 to match the ATM cell. In order to be controlled by the processing module 200, signal buses having the same specification must be used.

As described above, the signal buses used to match the ATM cell processing module 200 and the physical layer processing module 100 are as follows.

The division signal bus is a bus used to transmit the division signals for distinguishing the physical layer processing module 100 to be replaced and mounted according to the matching frequency, and the physical layer processing module 100 to be replaced is a DS-3 frequency. A division signal indicating whether the module matches with the STM-1 frequency or the module matches with the STM-4 frequency is transmitted to the ATM cell processing module 200, and the ATM cell processing module 200 processes the physical layer. The physical layer processing module 100 is initialized based on the division signal received from the module 100.

The UTOPIA interface bus is a bus used to transmit transmit enable signals, transmit / receive data, transmit / receive frame clocks, and transmit / receive cell start signals. It consists of a UTOPIA level 2 interface bus of bits.

The address bus and the data bus are buses used to initialize and control the physical layer processing module 100. The ATM cell processing module 200 receiving the division signal from the physical layer processing module 100 is an address bus and data. The physical layer processing module 100 mounted using the bus is initialized.

5 is a diagram showing the configuration of the physical layer processing module when the matched frequency is DS-3, and when the matched frequency is the DS-3, the physical layer processing module 110 includes a connector 111 and a transformer 113. ), A line matching unit 115, a UNI framer 117, and a division signal generator 119.

In such a configuration, the connector 111 physically connects the coaxial cable, and mainly uses a BNC connector.

The transformer 113 converts the voltage of the AC power received through the connector 111 into the voltage of the power used in the ATM matching device.

The line matching unit 115 amplifies and converts the signals received through the coaxial cable so that the UNI framer 117 can receive them, and transmits the signals received from the UNI framer 117 through the coaxial cable. Convert it.

The UNI framer 117 processes the signal received from the line matching unit 115 to transmit a frame to the ATM cell processing module 200 through the UTOPIA interface, and receives the frame received from the ATM cell processing module 200 through the UTOPIA interface. Where the frame is combined by the line matching unit 115 so as to be processed, the signal received from the line matching unit 115 is encoded, and then the encoded serial data is converted into parallel data, and the converted parallel data is converted into a frame. The frame is converted so that the converted frame can be processed by the ATM cell processing module 200. After mapping the ATM cell received from the ATM cell processing module 200 to the payload of the frame, the ATM cell is mapped, the frame is converted into parallel data, and the converted parallel data is converted into serial data and decoded.

As described above, the UNI framer 117 must be able to match the ATM cell processing module 200 and the UTOPIA level 2 interface to match the ATM cell processing module 200 that can accommodate up to the STM-4 frequency.

Meanwhile, the division signal generator 119 stores the identification values B1, B0; 0, 0 indicating that the physical layer processing module 110 matches the DS-3 frequency, and then stores the physical layer processing module 110. ) Is generated to generate a division signal based on the identification value.

6 is a diagram illustrating a configuration of a physical layer processing module when the frequency to be matched is STM-1, and the physical layer processing module 120 is a UTP5 cable / optical cable connector 121 when the frequency is matched to STM-1. And a UNI framer 123 and a division signal generator 129.

In such a configuration, the UTP5 cable / optical cable connection unit 121 physically connects the UTP5 cable / optical cable and, when connected with the optical cable, converts the optical signal received through the optical cable into an electrical signal.

The UNI framer 123 is matched with the UTP5 cable / optical cable connection 121 and PECL to process the signal received from the UTP5 cable / optical cable connection 121 to inform the ATM cell processing module 200 through the UTOPIA interface. And a signal combination to process the information received from the ATM cell processing module 200 through the UTOPIA interface so as to be processed by the UTP5 cable / optical cable connection 121, and transmitted from the UTP5 cable / optical cable connection 121. After recovering the lost and destroyed signal among the received signals (data / clock), convert serial data into parallel data, convert the converted parallel data into frames, and add overhead to the ATM cell processing module 200. To pass. After mapping the ATM cell received from the ATM cell processing module 200 to the payload of the frame, the ATM cell is mapped, the frame is converted into parallel data, and the converted parallel data is converted into serial data and decoded.

As described above, the UNI framer 123 must be able to match the ATM cell processing module 200 and the UTOPIA level 2 interface to match the ATM cell processing module 200 that can accommodate up to the STM-4 frequency.

Meanwhile, the division signal generator 129 stores the identification values B1, B0; 0, 1 indicating that the physical layer processing module 120 matches the STM-1 frequency, and then stores the physical layer processing module 120. ) Is generated to generate a division signal based on the identification value.

7 is a diagram illustrating a configuration of a physical layer processing module when the frequency to be matched is STM-1, and the physical layer processing module 130 is an optical cable connection unit 131 and a UNI when the frequency to be matched is STM-1. A framer 133 and a division signal generator 139 may be provided, and thus the detailed description thereof will be omitted since the structure is similar to that of the physical layer processing module when the matching frequency is STM-1.

8 is a flowchart illustrating an ATM matching method of a PSTN according to the present invention.

First, a corresponding physical layer processing module 100 is mounted according to a matching frequency. The mounting of the physical layer processing module 100 is performed by a system administrator. That is, the system manager implements a physical layer processing module that matches the DS-3 frequency when the matching frequency is DS-3, and physical layer processing that matches the STM-1 frequency when the matching frequency is STM-1. The module is mounted, and when the matching frequency is STM-4, the physical layer processing module matching the STM-4 frequency is mounted.

As described above, the division signal generation unit 109 of the physical layer processing module 100 mounted according to the frequency matched by the system manager is mounted on the ATM matching device and the DS cell processing module 200 itself is the DS. It transmits a division signal indicating whether a physical layer processing module processes a -3 frequency, a physical layer processing module processing an STM-1 frequency, or a physical layer processing module processing an STM-4 frequency. The ATM cell processing module 200 receiving the division signal from the layer processing module 100 classifies the type of the physical layer processing module 100 based on the received division signal, and determines the type of the separated physical layer processing module 100. According to the type, the UNI framer provided in the physical layer processing module 100 is initialized by controlling any one of the DS-3 initialization unit 220, the STM-1 initialization unit 230, and the STM-4 initialization unit 240. (S10, S12).

For example, as a result of classifying the type of the physical layer processing module 100 based on the division signal received from the physical layer processing module 100, the mounted physical layer processing module 100 matches the STM-4 frequency. In the case of a module, the controller 210 controls the STM-4 initialization unit 240 to initialize the UNI framer included in the physical layer processing module 100. The STM-4 initialization unit 240 may include an address bus and By initializing by setting the register of the UNI framer to a specific value using the data bus, the physical layer processing module 100 can match the STM-4 frequency to transmit and receive a frame.

When the UNI framer is initialized by the above-described process S12, the state information about the physical layer processing module 100 and the frame transmitted by the UNI framer are received and processed through the UTOPIA level 2 interface, and the counterpart is processed through the UTOPIA level 2 interface. The frame to be transmitted to the network is transmitted to the physical layer processing module 100 (S14).

ATM matching apparatus and method of the PSTN of the present invention is not limited to the above-described embodiment can be implemented in various modifications within the scope of the technical idea of the present invention.

According to the ATM matching apparatus and method of the PSTN of the present invention as described above, the physical layer processing module and the ATM layer processing module are configured in an independent form, respectively, and replaces only the physical layer processing module according to the matching frequency, thereby all frequencies are replaced. I can accept it. In addition, since only the physical layer processing module is developed, the development period can be shortened and the development cost can be reduced.

Claims (6)

A physical layer processing module individually designed and replaced according to a matching frequency; And a ATM cell processing module for initializing and controlling each of the physical layer processing modules according to a physical layer processing module to be mounted. The method of claim 1, wherein each physical layer processing module, An identification signal generator for storing the identification value for distinguishing the type of the physical layer processing module, and generating the classification signal according to the identification value and applying the identification signal to the ATM cell processing module when the physical layer processing module is mounted; ATM matching device of the PST. The method of claim 1, wherein the ATM cell processing module, A DS-3 initialization unit for initializing a physical layer processing module that matches the DS-3 frequency; An STM-1 initializer for initializing the physical layer processing module that matches the STM-1 frequency; An STM-4 initialization unit for initializing a physical layer processing module that matches an STM-4 frequency; And a controller configured to initialize the physical layer processing module by controlling any one of the DS-3 initializer, the STM-1 initializer, and the STM-4 initializer based on the division signal received from the division signal generator. ATM matching device of the Fiestien. The method of claim 1, wherein each physical layer processing module and ATM cell processing module, A division signal bus used to transmit a division signal for distinguishing types of physical layer processing modules mounted; A UTOPIA interface bus for transmitting transmit enable signals, transmit / receive data, transmit / receive frame clocks, and transmit / receive cell start signals; And an ATM matching device of a PST, characterized in that it is matched with an address bus and a data bus used to initialize and control the mounted physical layer processing module. The method of claim 1, wherein the ATM cell processing module, ATI M matching device of the PSTien characterized in that the operation is designed to accommodate the highest frequency of the matched frequency in order to match with each physical layer processing module. Receiving a division signal from a mounted physical layer processing module; The type of the physical layer processing module is installed based on the received classification signal, and among the DS-3 initializer, STM-1 initializer, and STM-4 initializer according to the type of the separated physical layer process module. Initializing a framer of the mounted physical layer processing module by controlling any one; ATI matching method comprising processing the ATM cell received from the initialized physical layer processing module through a UTOPIA interface.