KR100223054B1 - Optical network unit for concentrated customer - Google Patents

Abstract

The present invention is composed of two channel cells of 23 inches wide and 6U high (1U = 44.5mm) of 622 Mbps, which is composed of up to 180 lines of voice level, up to 60 lines of integrated information communication network (ISDN), and up to 64 lines of video on demand (VOD). It is a high-density subscriber optical multiplexing unit (ONU) that accepts four lines of DS1 (E) dedicated lines, ATM lines them, and multiplexes and demultiplexes them with 622Mbps SDH signals. By using ATM technology and bus routing technology, not only can it flexibly cope with the operating environment, but it can also use the service band efficiently and it also accepts V5.2 IDLC function, which is an international recommendation. It is possible to use the operation management terminal, so that the test function is convenient and operation maintenance is easy.

Description

Demand Dense Subscriber Optical Multiplexing Device

The present invention relates to a demand-density subscriber optical multiplexing device (Optical Network Unit: hereinafter referred to as ONU), which is composed of one transmission cell, which includes up to 180 general telephones, up to 180 public telephones, and a comprehensive information communication network (hereinafter referred to as ISDN). Maximum 60 lines, Video on demend (hereinafter referred to as VOD) Up to 64 lines, DS1 (1.544Mbps) / DS1 (E) (2.048Mbps), each accepting up to 4 lines, Asynchronous Transfer Mode: hereinafter referred to as ATM.) The present invention relates to a demand-density subscriber optical multiplexing device that multiplexes an input signal into a 622Mbps 'SDH (Sonet Digital Hirarchy)' signal and performs its reverse function.

In particular, this multiplexing and demultiplexing function is opposed to a digital digital master station (Host Digital Terminal: hereinafter referred to as HDT) in the country.

In general, broadband services such as high-speed data and video are required for existing subscribers based on voice and low-speed / mid-speed data due to the activation of information and communication, the opening of the communication market, and the evolution of subscriber optical cable.

However, there is no broadband subscriber transmission device that can accommodate a rapidly growing number of services at the same time, so the service cannot be efficiently provided.

Disclosure of Invention The present invention has been made in view of the conventional problems as described above, and an object of the present invention is to provide a new demand-density subscriber optical multiplexing device employing ATM technology that can efficiently and optimally accommodate various broadband services. The first purpose is to consist of one transmission self, 23 inches wide and 9U high (1U = 44.5mm), to accommodate PSTN (PSTN), VND and VOD services. An object of the present invention is to provide a demand-dense 622Mbps subscriber optical multiplexing device.

A second object of the present invention is to provide a V5.2 Integrated Digital Loop Carrier (hereinafter referred to as IDLC) function that performs a service by connecting to a DS1E trunk instead of an analog solid line (64 kbps) when the voice service is connected to an exchange. An object of the present invention is to provide a demand-density 622Mbps subscriber optical multiplexing device.

A third object of the present invention is a high bit rate digital subscriber line (HDSL) function of a modular type using a 2B1Q method inside a DS1E unit for long distance transmission in a DS1E (2.048 Mbps) dedicated line service. It is an object of the present invention to provide a high-density 622Mbps subscriber optical multiplexing device having

1 is a block diagram showing the front surface of the demand-intensive subscriber optical multiplexing apparatus according to the present invention.

2 is a block diagram showing the rear surface of the demand-intensive subscriber optical multiplexing apparatus according to the present invention.

3 is a block diagram showing an internal configuration of a demand-intensive subscriber optical multiplexing device according to the present invention.

* Explanation of symbols for the main parts of the drawings

1: Main control communication unit (MCCU) 2: Clock and optical transmission / reception unit (COTU)

3: expansion unit (EXTU)

4: DS1 (E) (Digital Signal Level-one (European))

5: Frame Unit (FRU) 6: Control and Maintenance Unit (CMU)

7: Channel Test Unit (CTU) 8: Channel Unit (CU)

9: Video channel unit (VCU)

In order to achieve the above object, the present invention provides a multi-channel common unit for connection and multiplexing with an external transmission device, and a transmission self for mounting a plurality of channel service units that are subscriber access units; A self front panel equipped with a current state and an error state of the optical multiplexing device and a reset button for initialization; A self-back panel equipped with an alarm, a test, an E1 input / output, an interprocessor communication connector and a power port for connection to the outside; The channel common unit among the units mounted on the transmission self transmits light to the main control communication unit (MCCU) that collectively controls the optical multiplexing device and is in charge of operation and maintenance such as alarm, provision, performance monitoring, and loopback functions. It receives and multiplexes and demultiplexes it, and the clock and optical transmission / reception unit (COTU) which is responsible for extracting system clock from line and ATM cell from transmission frame, and expansion unit (EXTU) which is a spare unit for future service expansion. And a DS1 (E) unit that emulates an ATM cell inputted from a power station and extracted from the clock and optical transmission / reception unit (COTU) to obtain a DS1 or DS1E level signal and perform the reverse function; The DS1E signal is extracted from the received ATM cell, and the extracted DS1E signal is applied to the frame analyzer to extract 64k units of data contained in the DS1E signal. To the frame unit (FRU), which performs the reverse function, and the control and maintenance unit (CMU) to perform the initialization, alarm processing, test and performance monitoring functions of the channel unit, and the subscriber according to the service. A channel test unit (CTU) for testing the line and call path characteristics of; The channel service unit among the units mounted in the transmission self is a video channel unit (VCU) for processing video control signals to be transmitted to an ATM network and providing a video service to a subscriber, and a general telephone / public telephone unit (ST / CP). And a basic rate matching unit (BRIU) for ISDN, and comprises a channel unit (CU) for receiving data and a clock from a frame unit (FRU), which is a frame interpreter.

The above objects, features and advantages will become more apparent from the following detailed description taken in conjunction with the accompanying drawings. Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

Figure 1 is a block diagram showing the front of the ONU according to the present invention, ONU Self is a structure for mounting a printed circuit board (PCB) consists of a board connector, a guide rail, a front panel, etc., 'IEC' and 'EIA', etc. In accordance with international standards, the front panel dimensions are 23 inches wide and 9U high and can accommodate PCBs with heights of 170 ± 3mm or 365 ± 3mm and 280 ± 3mm in depth.

The self-mounting unit can be divided into channel unit and channel common unit according to the function. The channel unit is composed of signal combination, control, 2M connection, codec (over-voice), loopback type, data rate selection, error correction, Multiple units (BRIU (Basic Rate Interface Unit) (ISDN unit)) with zero code insertion, transmission / reception data conversion unit (ideal data service), video subscriber matching, connectionless service matching, data modulation and demodulation functions, HD64N (64bps × N data unit), ST / CP (Subscriber Line Circuit-Telephone / Coin Phone), DPO / T, T, R / D, 2W / 4W EM, OCUDP, DS0DP, VCU (Video Channel Unit), FSU (Frame Relay Unit), LAU (LAN Unit), DS2U (6M Video Unit).

On the other hand, common units include 622Mbps data multiplexing and demultiplexing, clock reception, cell insertion and extraction, self-control, E1 access, E1 frame formation, cell filtering, tag insertion and removal for addresses, loop clock reception, system maintenance, power supply. A number of units with functions related to the main unit (MCCU (Main Cotrol and Communication Unit), COTU (Clock and Optical Tansmission / Receive Unit), DS1 (E), EXTU (Extention Unit), CTU (Channel Test Unit), FRU ( Frame Unit) and CMU (Control and Maintenance Unit).

Channel capacity was designed to accommodate the maximum number of subscribers per unit in consideration of economics and maintenance. That is, the voice level channel unit has 15 subscribers per unit, which is half of the common unit (4.5U) in consideration of the maintenance aspect, and the VCU has 8 subscribers in the 9U unit to minimize the influence of signal interference and design pattern. To accept.

The DS1E unit selectively accommodates modular one-pair or two-pair HDSL functionality within the unit for long-distance transmission, and eliminates redundancy throughout the system based on the reliability of the device.

The power required by the system is to minimize the size of the cabinet installed in the congested area of the apartment as much as possible, and because the current CAP-related devices require almost 3.3V of power, filtering 3.3V on the unit itself even if a separate power unit is installed. Considering two aspects in which module power must be additionally added, each module has a module power that is almost similar in terms of performance and cost, and is supplied with its own power supply.

The light emitting diode (LED) in front of the unit minimizes the type of light emitting diode in order to reduce power consumption since the display of the light emitting diode will not have a great effect when the ONU is installed in an unmanned country or outdoor where the operator does not reside.

On the other hand, the front of Self Main Control Unit (MCCU) has emergency information (Critical alarm: CR), Major alarm (MJ), General alarm (Minor: MN), and LB that collectively display the alarm status of the device. Install the LED and turn it on for 10 seconds when the button is pressed to test the status of the entire LED in the shelf.

In addition, the front panel of the clock and optical transmission / reception unit (COTU), DS1E, and VCU is equipped with an SF light emitting diode to signal an abnormal signal, and the front panel of the channel unit (CU) has a light emitting diode (BUSY LED) in use. To know.

In addition, each unit is equipped with an error LED (FAIL LED) indicating a fault condition of the circuit pack, and a reset button (RST button) for initializing the processor is mounted on the MCCU, BCMU, and the channel test unit (CTU).

In order to minimize the load, the MCCU, the main control unit, handles all the control and monitoring generated in the voice-level channel unit by the control and maintenance unit (CMU) and reports it to the MCCU through inter-processor communication (IPC). In addition, the test unit CTU is mounted next to the channel unit to facilitate pattern design.

Figure 2 is a block diagram showing the rear of the demand-intensive subscriber optical multiplexing apparatus according to the present invention, the connector on the back of the ONU is treated with a Z-pack (pack) connector or a metallic connector.

This is for easy connection with the external connection connector of the expansion unit 'EXTU (Extention Unit)'. This external connection connector is designed for high performance and safety because data and signals with the external expansion self are made at high speed. Two excellent 25-row, 125-pin Z-pack connectors have two spare pins for external connection.

It consists of seven power terminals, two for ring supply and five for power supply.

And the power is redundant so that only voice service can be backed up when AC is disconnected. This assumes that voice is primarily a subscriber service and video is provided additionally, and secondly, when AC is disconnected, the power of the home set-top box or TV is also cut off. In this case, the video service does not need to back up the battery when the power is cut off. Especially, if only the voice side performs the battery backup, it can provide enough backup time compared to the battery capacity. The power supply to the unit, and the B power supply accommodates the power distribution function to supply the VCU.

The Power Monitor (PWR MON) connector uses 9 pins of RS422 level to detect a number of alarms (rectifier failure, door open, etc.) from the power supply unit, and delivers them to the MCCU to notify the game devices in the country. IPC terminal for communication.

Figure 3 is a block diagram showing the internal configuration of the demand-density subscriber optical multiplexing apparatus according to the present invention, the voice-grade channel unit to accommodate 15 subscribers per unit as half (4.5U) of the common unit in consideration of maintenance aspects do.

The VCU unit accommodates 8 subscribers in a 9U unit to minimize signal interference, while the DS1E unit has a modular one-pair HDSL function in the unit for long-distance transmission, while redundancy in the system based on the reliability of the device. Is excluded.

Referring to the drawings, the functions of the entire system will be described as follows.

COTU of 622Mbps ONU receives 622M SDH light from HDT in domestic company and converts it into 622Mbps binarized electrical signal, and then synchronizes from 622Mbps bitstream provided by optical / electric conversion function using PLL. The clock is extracted and the received data is retimed using the reproduced clock.

At this time, the 622Mbps bitstream provided by the clock extraction / data retiming function recognizes the byte boundary and converts it into the byte datastream and inputs it to the 622M subscriber network interface (UNI) unit.

It handles section, line, and path overhead by receiving SONET / SDH frames through the byte serial interface. That is, it performs framing (A1, A2), descrambling functions, monitors alarm status, monitors section / line / pass bit interleaved parity (B1, B2, B3), and accumulates data with error counters for performance monitoring.

On the other hand, by extracting the A1 and A2 bytes on the received SDH frame, it is determined whether the frame is normal or error, and the pointer interpreter block is determined to determine the location of the path trace byte J1 byte of the path overhead on the input STM-4 stream. The pointers H1 and H1 bytes inputted are interpreted.

The ATM cell is extracted by identifying the synchronous payload envelope by J1 bytes for transmission with a fixed string length of 64 bytes or 16 bytes using timing information. In this case, discard the unused cells and store only the useful cells consecutively in 16-bit four FIFOs by 53 bytes.

In addition, the VCI value is stored and the information message, not the data, is stored in RAM and transferred to the MCCU.

Since the management information for the unit is fixed, the processor knows the type and slot number of the unit, so it maps the VPI / VCI value to the unit number and channel number.

Cells with this mapping tag are sent continuously on 32-bit by 32-M or 64-bit by 64M data buses. In a FIFO connected to the unit 622, at least one cell accumulates, a pulse for reading is sent high.

As a result, each channel unit continuously reads only the cell corresponding to the channel number of the unit.

The VOD unit is sent to the subscriber side through the 25M transmitter handler and the 16CAP modulator, and the control signal input from the subscriber side is output to the control unit through the 1.7M receiver handler and the four-phase phase modulation (QPSK).

In addition, for PSTN subscribers, cells with PSTN subscriber tags are aligned with E1 frame chips. Cells aligned to this frame are synchronized to the clock via AAL1 circuit emulation, and then only useful data cells are transferred to the subscriber unit.

In addition, ATM cells from FRUs or DS1 / Es are multiplexed to the 622M SDH and transmitted externally as 622M optical signals.

Hereinafter, the overall operation will be described in detail for each unit.

First, MCCU controls the device and performs functions related to operation and maintenance such as alarm, provisioning, performance monitoring and loopback.

Communication with HDT, a domestic device, is performed using an OAM cell, not a DCC channel. Since 16 ONUs are connected to one HDT, each ONU and HDT have to deal with communication data with a link access protocol (LAPD) for 16 HDTs for opposite communication.

Therefore, assuming that there is little communication information between the HDT and ONU, the use of a DCC channel which is always open with a fixed band regardless of the information to be communicated can be very uneconomical.

To solve this problem, each ONU and HDT set an IPC cell through a designated VCI and use it as a communication channel, and use it only when there is transmission data.

The front of the unit has an RS232C port to which the user terminal can be connected, allowing the operator to use this terminal to execute or monitor system-wide operations. In addition, RS422 connection port is located on the rear side to centrally manage telemetry alarms from the power supply and transmit them to HDT.

Second, the COTU consists of one chapter, and it can receive clocks from external input signals and has a 622Mbps optical interface function.

In other words, the received 622M optical signal is converted into an electrical signal for overhead processing, the ATM cell is extracted, and the cell is delivered to the FRU, DS1 (E) and VCU, and conversely, the FRU, DS1 (E), VCU It maps the ATM cell from the 622M class STM-4C multiplexed frame, inserts overhead, converts it into an optical signal, and transmits it to the opposing HDT.

In addition, the receiver monitors signal loss (LOS), frame loss (LOF), frame loss (OOF), temporary service interruption notification (AIS), far-end reception failure (FERF), and light emitting diode. It also performs performance monitoring via B2 and B3 bytes.

In addition, the clock is generated from the input 622Mbps signal using a digital phase locked loop (DPLL) to synchronize with the system to provide the system clock required throughout the system. This loop clock is switched to internal clock mode using self oscillation at all times.

Third, EXTU is a spare unit for use when expanding the line capacity for future increase of service.

Fourth, the DS1 (E) unit is a dedicated line service unit that fetches the data from the ATM cell extracted from the COTU to form a frame, and then transmits the data to the outside through the DS1 (E) line interface function. It performs the function of converting these received signals into ATM cells through AA1 circuit emulation and delivering them to COTU.

The DS1 (E) accommodates four lines of DS1E and DS1 at the same time per unit, respectively, and DS1E when inserting the HDSL function applied with the 1B pair or 2 pair 2B1Q transmission method of the distance extension medium module for long distance transmission. It only accepts 4 channels.

Fifth, the FRU consists of one piece to handle 180 voice subscribers 6E1.

This unit extracts the corresponding ATM cell from COTU, forms six DS1E frames through AAL1 circuit emulation, and delivers DS0 grade data to each channel unit.

At this time, it detects various alarms loaded in the frame and delivers them to the controller.

On the contrary, the voice signal or ISDN signal inputted from the channel side is composed of 2M frames to ATM ATM through AAL1 circuit emulation and then transmitted to COTU.

In order to selectively accept IDLC and UDLC functions when the voice line is connected to the exchange, V5.2 signal message extraction and insertion is performed to handle the V5.2 protocol under the control of the CMU, and there is a timeslot assignment function. Depending on the concentration of exchanges, 1: 1 to 1: 6 aggregation is possible through provisioning.

Sixth, CMU is a unit that controls, operates and tests CU and FRU and performs protocol with exchange. It supports PSTN, control, link control, BCC protocol to support IDLC interface, V5.2 data link and It has mapping function and AN frame relay function. It also has an IPC function that sends information about channel units to the MCCU and receives provision data from the MCCU.

Seventh, the CTU has the capability to test the subscriber line out or in with the subscriber test unit. This unit has the capability to measure line resistance, capacitance, voltage and current of voice level and pattern test through network termination device (NT) and call test and loop for ISDN test.

Eighth, the CU receives data and clock in units of 64K from the FRU, which is a frame interpreter. Types of CUs include voice-class telephone / outbound public telephone (ST / CP) and ISDN (2B + D) (BRIU) units.

The ST / CP unit accommodates 15 lines per unit, and the BRIU unit accommodates 5 lines per unit. After the CMU detects the state change of hook / off of ST / CP, it configures it as V5.2 message and transmits it to the exchange by using LAPD controller.

Conversely, a message such as a ring issue command received at the exchange gives a command to the ST / CP via the control bus.

The LAPD data received from the BRIU extracts the necessary timeslot and passes it to the LAPD controller. The CMU transfers this data to the exchange through the frame relay function and performs its reverse function. The front of the unit has LEDs for faults, operating conditions and tests.

The BRIU uses two timeslots per subscriber for data, has a separate common line channel for signals, has a sealing current supply function, feeds using module power, and an operation channel within an ISDN superframe. It has the advantage of being able to perform interval bit error ratio (BER) test using an exchanger or a measuring instrument.

Ninth, the ACU is a unit for processing video signals flowing into an ATM cell and video control signals to be transmitted to an ATM network. The ACU has a 16CAP modulation for extracting a video signal and synthesizing it into a subscriber signal and a QPSK modulation function for restoring control signals. The signal created here is connected to the subscriber line of the channel unit. There are LEDs on the front to indicate fault, signal loss and operation status.

As described in detail above, the 622Mbps ONU of the present invention is used in a broadband subscriber network, and can accommodate not only existing voice and ISDN services but also multimedia services that are expected to increase in the future, ATM technology and buses. There is an advantage of maximizing the efficiency of subscriber bandwidth using routing technology.

It also has the advantage of eliminating the opposing channel unit in HDT by enabling the device to access the IDLC function using DS1E rather than solid line with the switch for voice and ISDN service.

In addition, preferred embodiments of the present invention are disclosed for the purpose of illustration, those skilled in the art will be able to various modifications, changes, additions, etc. within the spirit and scope of the present invention, such modifications and modifications belong to the following claims You will have to look.

Claims (23)

A transmission self for mounting a plurality of channel common units for connection and multiplexing with an external transmitter, and a plurality of channel service units that are subscriber access units; A self front panel equipped with a current state and an error state of the optical multiplexing device and a reset button for initialization; A self-back panel equipped with an alarm, a test, an E1 input / output, an interprocessor communication connector and a power port for connection to the outside; The channel common unit among the units mounted on the transmission self transmits light to the main control communication unit (MCCU) that collectively controls the optical multiplexing device and is in charge of operation and maintenance such as alarm, provision, performance monitoring, and loopback functions. It receives and multiplexes and demultiplexes it, and the clock and optical transmission / reception unit (COTU) which is responsible for extracting system clock from line and ATM cell from transmission frame, and expansion unit (EXTU) which is a spare unit for future service expansion. And a DS1 (E) unit that emulates an ATM cell inputted from a power station and extracted from the clock and optical transmission / reception unit (COTU) to obtain a DS1 or DS1E level signal and perform the reverse function; The DS1E signal is extracted from the received ATM cell, and the extracted DS1E signal is applied to the frame analyzer to extract 64k units of data contained in the DS1E signal. To the frame unit (FRU), which performs the reverse function, and the control and maintenance unit (CMU) to perform the initialization, alarm processing, test and performance monitoring functions of the channel unit, and the subscriber according to the service. A channel test unit (CTU) for testing the line and call path characteristics of; The channel service unit among the units mounted in the transmission self is a video channel unit (VCU) for processing video control signals to be transmitted to an ATM network and providing a video service to a subscriber, and a general telephone / public telephone unit (ST / CP). D) and a basic rate matching unit (BRIU) for ISDN, comprising a channel unit (CU) for receiving data and clocks from a frame unit (FRU), which is a frame interpreter. Device. The system according to claim 1, wherein the transmission self is equipped with 21 subscriber service units and 6 common units, and includes voice subscribers up to 180 subscribers, ISDN up to 60 subscribers, VOD up to 64 subscribers, DS1 and DS1E. A demand-intensive subscriber optical multiplexing device, each of which accommodates up to four subscribers. The communication system according to claim 1, wherein the main control communication unit (MCCU) uses a DCC channel or an ATM cell for communication with a powerhouse device in a domestic company, and connects a user terminal to a front surface to execute or monitor an operation throughout the system. Demand dense subscriber optical multiplexing device, which has a RS232C port, and has a RS422 connection port on the rear side for centrally managing telemetry alarms generated by other self and transmitting them to a domestic power station. The clock and optical transmitting / receiving unit (COTU) according to claim 1, wherein the clock and the optical transmitting / receiving unit (COTU) are composed of one sheet, and receive a clock receiving function and an optical signal input from an externally input signal, convert the electrical signal into an electrical signal, and process the overhead. Extracting an ATM cell, delivering the cell to a frame unit (FRU), a DS1 (E) and a video channel unit (VCU), and vice versa; . The apparatus of claim 4, wherein the receiver of the clock and the optical transmission / reception unit (COTU) monitors a plurality of alarms and has a performance monitoring function through a specific byte in a frame. The method of claim 1, wherein the rear surface of the expansion unit (EXTU) is equipped with a plurality of Z-pack connector of 125 pins so as to have easy connection with the external connection connector and sufficient spare pin, data and signal with the external expansion self A demand-intensive subscriber optical multiplexing device characterized by ensuring performance and safety when connected. 2. The DS1 (E) unit of claim 1, wherein the DS1 (E) unit forms a frame by patching corresponding data from an ATM cell extracted from the clock and an optical transmission / reception unit (COTU), and then, through the DS1 (E) line interface function. A demand-intensive subscriber optical multiplexing device which transmits to the outside and performs the reverse function. 8. The DS1 (E) unit according to claim 7, wherein the DS1 (E) unit accommodates four lines each of DS1E and DS1 at the same time, and inserts a 1 pair or 2 pair high bit rate digital subscriber line (HDSL) function of a module type which is a distance extension medium. The demand-density subscriber optical multiplexing device, which only accommodates 4 channels of DS1E. The apparatus of claim 1, wherein the frame unit (FRU) is composed of one piece, each of which processes a voice level 180 line or an ISDN 60 line, and has an emulation function, an alarm detection and insertion function, and a loopback function for ATM cell processing. Demand density subscriber optical multiplexing device, characterized in that. 10. The apparatus of claim 9, wherein the frame unit (FRU) is internationally controlled by a control and maintenance unit (CMU) to selectively accommodate analog lines and digital lines (E1) when connecting voice level lines to exchanges. A demand-intensive subscriber optical multiplexing device having a signal message extraction and insertion function for processing the recommendation V5.2 protocol. The V5.2 International Direct Digital Loop Carrier (IDLC) standard of claim 10, wherein the voice subscriber line has a common line signaling channel and a timeslot management channel for direct connection to DS1 (E) when connected to a switch. Dense subscriber optical multiplexing device, characterized in that to satisfy. 12. The method of claim 11, wherein for the direct digital loop carrier (IDLC) function, channels 0 and 16 of the first trunk among trunks provided by the optical multiplexing device are allocated to the signaling channel and the timeslot management channel, and 0 of the second trunk is included. Demand density subscriber optical multiplexing device characterized in that the times and 16 timeslots can be used for protection switching by a selection function. The nonvolatile memory device of claim 9, wherein the frame unit (FRU) is configured to store provision data and performance monitoring data in the event of failure or dismounting of a control and maintenance unit (CMU), which is a control unit of a channel unit. Demand-type subscriber optical multiplexing device comprising a RAM. The CMU of claim 1, wherein the control and maintenance unit (CMU) is a unit that controls, operates, and tests a channel unit (CU) and a frame unit (FRU), and performs a protocol with an exchange side. It supports public telephone network (PSTN), control, link control and BCC protocol to support (IDLC) interface, and has V5.2 data link and mapping function and access network (AN) frame relay function. Type subscriber multiplexing device. The processor of claim 14, wherein the control and maintenance unit (CMU) transfers all information about the channel unit (CU) to the main control communication unit (MCCU) and is capable of receiving data related to provisions from the MCCU. A demand-density subscriber optical multiplexing device having an IPC function. The method of claim 1, wherein the channel test unit (CTU) is divided into the line side and the call line side of the subscriber line to automatically measure the line resistance, capacitance, voltage, current of the voice level, ISDN test Demand dense subscriber optical multiplexing device having a function of performing a pattern test through a call test and a loop with a network termination device (NT). The VCU of claim 1, wherein the video channel unit (VCU) serves as a modulation for extracting a video signal and synthesizing it into a subscriber signal and a modulation for restoring a control signal, the modulated signal being connected to a subscriber line of the channel unit. Dense subscriber optical multiplexing device, characterized in that the input. The apparatus of claim 1, wherein the channel service unit (CU) has a unit failure, make busy, busy, data, signal loss, and loopback light emitting diode on a front surface of the unit. The apparatus of claim 1, wherein the public telephone / public telephone unit (ST / CP) is configured to selectively accommodate a public telephone and a public telephone. The base rate matching unit (BRIU) for an ISDN, according to claim 1, uses two timeslots per subscriber for data, has a separate common line channel for signals, and supplies a sealing current supply function and a power supply function using module power. Demand density subscriber optical multiplexing device, characterized in that it has a. 21. The base rate matching unit (BRIU) for ISDN has a loopback function using an operation channel (EOC) in an ISDN superframe, so that an interval bit error ratio (BER) test can be performed using an exchange or a measuring instrument. Dense subscriber optical multiplexing device. The apparatus of claim 1, wherein the power applied to the power port mounted on the rear panel of the self is duplicated so that only a voice level service can be backed up by a battery when AC is disconnected. The power-monitor connector of the interprocessor communication connector mounted on the self-back panel detects a plurality of alarms generated from a power supply unit using RS422-level pins, and then passes to the main control communication unit (MCCU). The demand-dense subscriber optical multiplexing device, characterized in that it transmits and informs the power device in the national history.

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