KR19990086055A - Network Access Device in ADS Broadband Service Network - Google Patents

Abstract

The present invention provides an efficient and economical network access device by implementing a network access system in an independent self unit or rack unit according to the number of subscribers and system requirements in a network access device having one network link per rack. The present invention relates to a network access device for a DSL broadband service network. The present invention relates to a network access unit in a central station for interfacing a broadband public network and a subscriber unit, a network connected to an ATM switch to control an interface of upstream and downstream data. Control and management unit that interfaces the control and management information through the interface unit, the ADSL network management unit and the Ethernet interface, and provides a control line interface for system initialization, configuration and control through the serial interface, and the control by the control and management unit Delivered through the interface unit The downlink data is de-multiplexed and delivered to the subscriber side, and the ATM board is extracted from the uplink data delivered from the analog phone separation unit, and multiplexed to the network interface unit. Economical network connection can be realized.

Description

Network Access Device in ADS Broadband Service Network

The present invention relates to an asymmetric digital subscriber line (ADSL) broadband service system. In particular, an independent self (Shelf) according to the number of subscribers and system requirements in a network access device having one network link per rack (RACK) The present invention relates to a network access device in an ADS broadband service network which attempts to obtain an efficient and economical network access device by implementing a network access system in units or racks.

In general, an important feature of ADSL systems is the ability to provide high-speed digital data services simultaneously on existing twisted pair copper (POTS) networks without interfering with the public office telephone system (POTS). .

It is a technology that increases bandwidth to simultaneously transmit multimedia information such as voice, graphics, and video while using existing telephone lines. Therefore, it is receiving attention as a service network that can deliver multimedia information to subscribers without incurring network installation costs.

Thus, new services can be created that can be provided to telephone subscribers such as high-speed Internet, online access and telecommuting, and video on demand (VOD). In addition, there is no need to install a new line, so it is possible to implement the service more economically and faster than using other systems.

The line coding scheme of ADSL includes DMT (Discrete Multi-Tone) and CAP (Carrier Amplitude).

The line code method is a technology that modulates and demodulates digital data and transmits it on a twisted pair. Among the DMT methods set in ANSI, the standard can transmit data at a downlink rate of up to 8Mbps and an uplink rate of about 640Kbps. have.

On the other hand, the network subscriber system consisting of the existing rack (rack) is determined by the number of subscribers that can be supported in a rack-type form according to the overall configuration of the rack, because the system itself is based on the rack, Even if a large volume occupies a disadvantage that requires a lot of space.

In addition, even in a system having a small number of subscribers, since the system itself is designed based on a rack, there is a problem in that the efficiency of system configuration is also reduced.

Accordingly, the present invention has been proposed to solve the above problems of the prior art,

The present invention provides an efficient and economical network access device by implementing a network access system in an independent self unit or rack unit according to the number of subscribers and system requirements in a network access device having one network link per rack. The purpose of the present invention is to provide a network access device in an ADSL broadband service network.

A more detailed object of the present invention is configured to have a separate network high-speed interface per self, and at the same time by connecting the network interface between the self in a ring (Ring) form, one self or a plurality of self configurable system according to the number of subscribers It is to be done.

Apparatus according to the present invention for achieving the above object,

In an ADSL broadband service system having an ADSL network connection unit for switching between high speed data obtained from an ATM switch and an analog telephone obtained from a public telephone network, an ADSL network management unit, and a central station including a public telephone network switch and an analog telephone separation unit,

The ADSL network connection portion,

A network interface unit connected to the ATM switch and controlling an interface of uplink data and downlink data;

A control and management unit that interfaces control and management information through the ADSL network management unit and an Ethernet interface and provides a control line interface for system initialization, configuration, and control through a serial interface;

The downlink data transmitted through the network interface unit is controlled by the control and management unit to be demultiplexed and transmitted to the subscriber side, and only the ATM cell is extracted and multiplexed from the upstream data transferred from the analog phone separation unit to the network interface unit. Characterized in that consists of a subscriber board consisting of a plurality of ADSL subscriber board to deliver.

Another apparatus according to the present invention for achieving the above object,

In an ADSL broadband service system having a central station including an ADSL network connection, an ADSL network management unit, a public telephone network switch, and an analog telephone separation unit for switching between high-speed data obtained from an ATM switch and an analog telephone obtained from a public telephone network.

The ADSL network connection portion,

A network interface unit connected to the ATM switch and controlling an interface of uplink data and downlink data;

A control and management unit that interfaces control and management information through the ADSL network management unit and an Ethernet interface and provides a control line interface for system initialization, configuration, and control through a serial interface;

The downlink data transmitted through the network interface unit is controlled by the control and management unit to be demultiplexed and transmitted to the subscriber side, and only the ATM cell is extracted and multiplexed from the upstream data transferred from the analog phone separation unit to the network interface unit. Characterized in that the self consisting of a subscriber board including a plurality of ADSL subscriber board to deliver.

In the above, the ADSL subscriber board,

A cell bus interface controller for multiplexing and demultiplexing ATM cells on a cell bus;

A cell multiplexing / demultiplexing unit which is provided between the cell bus interface control unit and an ATM handler at a later stage to multiplex and demultiplex cell streams transmitted and received between the cell bus interface control unit and the ATM handler;

The ATM handler for inserting and removing idle cells of the transmitted and received ATM cells, scramble and descramble cell payload, cell processing, HEC checking and generation, and converting an ATM utopia interface to a modem byte interface;

An ADSL transceiver for demodulating the ATM cell delivered from the ATM handler and demodulating the ATM cell delivered from the subscriber side;

A line driver interposed between the ADSL transceiver and the analog telephone separator to perform a line interface;

A microprocessor for multiplexing / demultiplexing control of the cell bus interface control unit, cell stream multiplexing / demultiplexing control of the cell multiplexing / demultiplexing unit, cell processing control of the ATM handler, and modulation / demodulation control of the ADSL transceiver. It is characterized by.

In the above, the network interface unit,

A first transceiver connected to a broadband network and interfacing an ADSL frame through a 45 Mbps T3 or 155 Mbps OC-3c interface;

A first user network processor connected to the first transceiver and extracting only an ATM cell from a downlink or uplink data frame of T3 or OC-3c;

Demultiplex the ATM cells extracted from the first user network processor, multiplex ATM cells of uplink data, and deliver only cells for the corresponding subscriber self to the cell bus interface, and cells for other subscriber self are the other subscriber self. A cell multiplexer / demultiplexer for transmitting to the side;

A cell bus interface controller which delivers the demultiplexed subscriber cells in the cell multiplexer / demultiplexer to a cell bus and delivers the subscriber cells via the cell bus to the cell multiplexer / demultiplexer;

The cell delivered to the other subscriber self side obtained in the cell multiplexing / demultiplexing unit is delivered to the second transceiver, and only the ATM cell is extracted from the uplink data of the other subscriber self side delivered through the second transceiver to the cell multiplexing / demultiplexing. A second user network processor for delivering to the multiplexer;

The other subscriber cell obtained from the second user network processor transmits to another subscriber self side through a ring-type interface, and the subscriber data transferred from the other subscriber self side is composed of a second transceiver to deliver to the second user network processor. do.

In the above, the cell multiplexing / demultiplexing unit,

A first-in, first-out (first-in, first-out) unit for first-in first-out of a downlink subscriber cell obtained from the first user network processor;

A cell demultiplexer for demultiplexing subscriber cells obtained from the first first-in-first-out machine;

A second first-in, first-out first-in, first-out of the demultiplexed cell obtained from the cell demultiplexer and delivered to the subscriber side connected to the self;

A third first-in, first-out (first-in, first-out) unit for first-in first-out of the demultiplexed cell obtained from the cell demultiplexer and delivering it to another subscriber self;

A fourth first-in, first-out-first-out to first-in, first-out subscriber cell connected to its self obtained from the cell bus interface controller;

A first-in, first-out-first-out to first-in, first-out the subscriber cell delivered from the other subscriber self side obtained from the second user network processor;

A cell multiplexer for multiplexing subscriber cells respectively obtained by the fourth and fifth first-in-first-out machines;

And a sixth first-in, first-out of the subscriber multiplexed in the cell multiplexer to deliver to the first user network processor.

1 is a block diagram of a network connection device having a ring-shaped network link to which the present invention is applied;

FIG. 2 is a detailed configuration diagram of the ADSL-LT subscriber board of FIG. 1; FIG.

3 is a detailed configuration diagram of the network connection portion according to the present invention;

(a) is a system configuration diagram when a network connection unit is implemented in a rack unit,

(b) is a system configuration diagram when a network connection unit is implemented in units of self,

4 is a detailed configuration diagram of the network interface board of FIG.

<Explanation of symbols for the main parts of the drawings>

100: data exchange network 200: public telephone network

300: central station (ADSL network connection) 310,310 ': ADSL network connection

311: network interface unit 312: control and management unit

313: Subscriber board unit 320: ADSL network management unit

330: public telephone network switch 340: analog telephone separation unit

350: local control terminal 400: twisted pair

500: subscriber

Hereinafter, described in detail with reference to the accompanying drawings, preferred embodiments of the present invention.

1 is a block diagram of an ADSL system to which the present invention is applied.

As shown therein, a data exchange network unit 100 which performs ADSL broadband service over a broadband public network, and high-speed data obtained through the data exchange network unit 100 and an analog telephone obtained from a public telephone network 200 are mutually separated from each other. The central station 300, which is an ADSL network access system for switching, and the subscriber station 500, which is connected to the central station 300 and the twisted pair 400, transmits and receives high-speed data and analog telephones to and from the subscriber's home. It is composed.

In the above description, the data exchange network unit 100 is a broadband public network 150 connected to an instruction set processor (ISP) 110, a server 120, the Internet 130, and an ATM switch 140. ), A router 170 for connecting the Internet 160, and an ATM gateway 180 for an ATM cell interface between the router 170 and the ATM switch 140.

In addition, the subscriber unit 500 includes an analog telephone separation unit 511 connected to the twisted pair 400 to separate subscriber data from an analog phone and an ADSL transceiver 512 to interface subscriber ADSL data. Transmits and receives 25 Mbps data of the ADSL subscriber modem 510, the general telephone 520 present on the subscriber side and connected to the analog telephone disconnecting unit 511, and the ATM form obtained from the ADSL subscriber modem 510. The terminal 530 is connected to the ADSL subscriber modem 510 and is configured of an interface device 540 for Ethernet 10BaseT connection and a plurality of terminals 550 connected thereto.

The operation of the ADSL broadband service network to which the present invention configured as described above is applied is as follows.

First, as shown in FIG. 1, a network access device to which the present invention is applied is connected to a backbone network 100, that is, a data backbone network and an ATM network, for an interface of high-speed data, and an analog telephone is public. It is connected to the PSTN network, which is the telephone network 200.

And the existing twisted pair 400 is used as it is for the data and the interface of the analog phone with the subscriber.

That is, the ADSL network access system 300 connects ATM 155Mbps OC-3c or ATM 45Mbps T3 to the uplink network access board from the broadband network, and the data input from the broadband network is multiplexed on the ATM cell bus. The demultiplexed or switched data modulated via the ADSL subscriber board is mixed with the analog telephone data obtained from the public telephone network 200 and transmitted to the subscriber unit 500 through the existing twisted pair 400.

Here, the telephone line connected to the subscriber is separated from the telephone service data through the analog telephone separator 511 in the subscriber's premises, and only the modulated ADSL data is input to the subscriber system, and in the ADSL transceiver 512, the ADSL demodulation and the ADSL frame are performed. ATM cell data extraction is performed.

If the subscriber interface to the PC or TV is 25 Mbps of ATM Forum, it is connected to PC 530 or TV via UTP-3 cable via 25 Mbps I / F TC + PMD (Physical Medium Dependent) device. .

In addition, when the subscriber interface to the PC or TV is Ethernet 10BaseT, ATM cell data extracted from the interface unit 540 may be segmented & reassembly (SAR) function of ATM Adaptation Layer and cell demultiplexing based on VC. Convert to Ethernet packet data and interface to PC 550 through MAC controller and line driver.

Meanwhile, the uplink data transmitted from the subscriber via the ADSL subscriber unit 500 through the telephone line 400 is transferred from the ADSL frame through the ADSL transceiver of the ADSL subscriber board (described in detail below) of the central station 300, which is a network access system. After extracting ATM cell data, the ATM cell data is multiplexed on an ATM cell bus and connected to the data switching network unit 100, which is the broadband network, through an uplink network access board.

Here, the central station 300, which is an ADSL network access system, controls and operates an ADSL subscriber board and an uplink network access board, and collects subscriber information and network related state information from these boards and transmits them to the ADSL network management system. Have an operation board (described in more detail below). The control / operation board performing such network control and network operation operates under the SNMP Agent protocol.

Hereinafter, the ADSL network access device (central station), which is the core of the present invention, will be described in detail.

First, the ADSL network access device (central station) 300 to which the present invention is applied receives the downlink data input from the broadband network through the network access board, demultiplexes the data on the ATM cell bus, separates the ATM cells, and transmits them to the subscriber. Uplink data transmitted from the subscriber side is multiplexed on the ATM cell bus and transmitted to the broadband network through the network access board; An ADSL network manager 320 for controlling an uplink network access board in the ADSL network access unit 310 and collecting and subscribing subscriber information and network related information from the board to efficiently control and operate a network; A public telephone network switch 330 connected to the PSTN network 200 to switch subscriber analog telephones; When the subscriber data transmitted from the ADSL network access unit 310 is transmitted downward, the subscriber data and the analog telephone transmitted from the public telephone network switch 310 are mixed and transmitted to the subscriber unit 500, and the subscriber unit 500 is transmitted. The uplink data transmitted from the analog phone and the analog phone are separated, and the subscriber data is transmitted to the ADSL network connection unit 310, and the analog phone is composed of an analog phone separation unit 340 for transmitting to the public telephone network switch 330.

Here, the ADSL network connection unit 310 may be configured in a self unit and a rack unit according to the number of subscribers. When the number of subscribers is small, the ADSL network connection unit 310 configures the system only in self units as shown in FIG. When the number is large, as shown in FIG. 3 (b), a rack unit system including a plurality of shelves is configured as one rack.

First, the self-unit network connection apparatus according to the first embodiment of the present invention is connected to the ATM switch 140 in the data switching network unit 100 as shown in FIG. And a network interface unit 311 for controlling an interface of downlink data, and an interface with control and management information through the Ethernet interface with the ADSL network management unit 320, and a control line interface for system initialization, configuration, and control through a serial interface. The downlink data transmitted through the network interface unit 311 by the control and management unit 312 and the control and management unit 312 to provide a demultiplexed and forwarded to the subscriber side, the analog telephone separation unit ( A plurality of ATM cells are extracted from the upstream data transmitted from the packet 340 and multiplexed to the network interface unit 311. Board consists of subscriber unit 313 consisting of - the ADSL subscriber board (313-n 313-1).

The self-unit ADSL network connection unit 310 may be configured by connecting a local control terminal 350 for local control to the control and management unit 312.

When the ADSL network connection unit of the self unit is configured, it connects to the broadband network through the uplink network access board in the self, and inserts the self into a separate box having an analog telephone separation unit 340 suitable for the number of subscribers supported by the self. The self unit system is configured.

The network management unit 320, which is a control / management board, communicates control and management information through an Ethernet interface to the ADSL network management system, and a control line interface through a terminal for system initialization, configuration, and control through a serial interface. Provides (Command Line Interface). For control line interface, use serial interface such as DB25 or DB9 RS-232.

Next, the ADSL network connection 310 'which is the second embodiment of the present invention when the number of subscribers constitutes the ADSL network connection 310 in units of racks is as shown in FIG. The network interface unit 311 is connected to the ATM switch 140 and controls the interface of the upstream data and the downlink data, and the control and management information is interfaced through the ADSL network management unit 320 and the Ethernet interface. The control and management unit 312 which provides a control line interface for initialization, configuration and control, and the downlink data transmitted through the network interface 311 by the control of the control and management unit 312 are demultiplexed to provide subscribers. The network interface, and extracts and multiplexes only the ATM cell from the uplink data transmitted from the analog telephone separation unit 340. A plurality of self 310 consisting of the subscriber board unit 313 including a plurality of ADSL subscriber boards 313-1-313-n to be delivered to the unit 311 (310 ..... 310 + n) It is constructed by merging.

Here, the ADSL network connection unit 310 ′ of the rack unit may be configured by connecting a local control terminal 350 for local control to the control and management unit 312.

When implementing the ADSL network connection unit by the rack unit, about four ADSL line shelves are provided per rack, and the uplink network connection board of the self connected to the uplink network connection of the rack unit processes only the corresponding data information. The unconnected data is connected to another self's uplink network access board through the ring structure. Similarly, the uplink data of the self is multiplexed with the upstream data coming from the other self through the ring-shaped structure in the uplink network access board and transferred to the other self, and the rack-level network access link from the final ring end self (master self) to the broadband network. Will be connected.

Similarly, control / management information is transferred and collected from the control / management board of each self to the ring structure through the serial interface, so that the control / management board of the ring-end self is connected to the ADSL network management system through the Ethernet interface and serial to the control terminal. Provides a control line interface through the interface.

For ease of system implementation and support of the maximum subscriber board per self, the uplink network access board and the control / management board may be combined into one board.

Here, the control / management board in the system master self that is directly connected to the broadband network and directly connected to the ADSL network management system should provide status information on the broadband network access interface separately, and has additional control / management functions for the entire system. Should be

Hereinafter, the function and operation of each part will be described in more detail.

First, in the case of implementing the ADSL network access device in the unit of self or in the case of implementing the ADSL network access unit in the unit of rack, the configuration of each self is the same, only the rack unit of self will be described below.

First, in FIG. 1, the high speed downlink data transmitted from the data switching network unit 100 is interfaced at the network interface unit 311 in the ADSL network connection unit 310.

That is, the network interface unit 311 includes a first transceiver 311a connected to a broadband network and interfacing an ADSL frame through a 45Mbps T3 or 155Mbps OC-3c interface as shown in FIG. 4; A first user network processor 311b connected to the first transceiver 311a and extracting only an ATM cell from a downlink or uplink data frame of T3 or OC-3c; Demultiplex the ATM cells extracted by the first user network processor 311b, multiplex the ATM cells of uplink data, and transfer only cells for the corresponding subscriber self to the cell bus interface unit; A cell multiplexing / demultiplexing unit 311c which transmits to another subscriber self side; A cell bus interface controller which delivers the demultiplexed subscriber cells from the cell multiplexer / demultiplexer 311c to a cell bus and delivers the subscriber cells transmitted through the cell bus to the cell multiplexer / demultiplexer 311c. 311d); The cell transmitted to the other subscriber self side obtained from the cell multiplexer / demultiplexer 311c is transferred to the second transceiver 311e, and the ATM is transmitted from the uplink data of the other subscriber self side transferred through the second transceiver 311e. A second user network processor 311f which extracts only cells and delivers them to the cell multiplexer / demultiplexer 311c; The second subscriber cell obtained from the second user network processor 311f delivers to the other subscriber self side through a ring interface and the subscriber data transferred from the other subscriber self side passes to the second user network processor 311f. It consists of a transceiver 311e.

In the above, the cell multiplexing / demultiplexing unit 311c includes: a first-in, first-out (31) for first-in, first-out of a downlink subscriber cell obtained from the first user network processor (311b); A cell demultiplexer (32) for demultiplexing subscriber cells obtained from the first-in, first-out (31); A second first-in first-out (33) for first-in first-out of the demultiplexed cell obtained from the cell demultiplexer (32) and delivering it to the subscriber side connected to the self; A third first-in first-out (34) for first-in first-out of the demultiplexed cell obtained from the cell demultiplexer (32) and delivering it to another subscriber self side; A fourth first-in, first-out (35) for first-in first-out of a subscriber cell connected to its own self obtained from the cell bus interface controller (311d); A fifth first-in, first-out (36) for first-in first-out of a subscriber cell delivered from another subscriber self side obtained from the second user network processor (36); A cell multiplexer (37) for multiplexing the subscriber cells respectively obtained by the fourth and fifth first-in-first-out (35) (36); A sixth first-in, first-out (38) for first-in, first-out of the subscriber cell multiplexed by the cell multiplexer (37) and delivering it to the first user network processor (311b).

When the high-speed data is transmitted to the first transceiver 311a, which is the uplink network access board of the master self, through the 45Mbps T3 or 155Mbps OC-3c interface, the network interface unit 311 configured as described above is configured as the first user network processor 311b. ) Extracts only ATM cells from the T3 or OC-3c transmission frame, identifies the cell boundary of the ATM layer, scrambles / descrambles the cell layer, checks and generates header error control (HEC), and creates and removes Idle cells. It performs a Transmission Convergence (TC) function such as deframing and a PMD function such as Clock and Data Recovery (CDR), and delivers the cells that have been processed to the cell multiplexer / demultiplexer 311c.

The first first-in-first-out 31 in the cell multiplexing / demultiplexing unit 311c first-in-first-outs the delivered ATM cell, and the cell demultiplexing unit 32 demultiplexes the delivered cell and VPI / The VCI is inspected and delivered only the cells for the subscriber self to the second first-in-first-out (33), and the cell to be delivered to the other subscriber self is delivered to the third-in, first-out (33).

The second first-in-first-out unit 33 first-in-first-outs the delivered demultiplexed subscriber cell to the cell bus interface controller 311d, and the cell bus interface controller 311d transmits to the respective ADSL subscriber boards on the cell bus. Routing table and tag management, bus arbitration, etc. to perform multiplexing / demultiplexing are performed, and the delivered cell is floated on the cell bus.

In addition, the third-in-first-out (34) first-in, first-out of the cells to be delivered to the other subscribers self to deliver to the second user network processor (311f), the second user network processor (311f) is the first user network processor described above It performs the same function as 311b, processes the transferred ATM cell, and transfers the processed ATM cell to the second transceiver 311e.

The second transceiver 311e transfers the cell of the other subscriber self delivered from the second user network processor 311f to the other subscriber self 311-1 through the connected ring structure, and the other subscriber self ( Cells delivered from 311-1 are collected and delivered to the second user network processor 311f.

Then, the second user network processor 311f processes a cell obtained from another subscriber self delivered from the second transceiver 311e and inputs it to the fifth first-in-first-out 36.

In addition, the subscriber cell in the subscriber self obtained from the cell bus interface controller 311d is transferred to the fourth first-in-first-out 35, and the cell multiplexer 37 obtains itself from the fourth first-in-first-out 35. Multiplexing the cell of the subscriber connected to the self of the subscriber and the subscriber cell obtained from the other subscriber self obtained from the fifth first-in-first-out 36 to transfer to the first user network processor 311b through the sixth first-in-first-out 38 Do it.

Then, the first user network processor 311b processes the downlink data, which is the subscriber data, and transmits the downlink data, which is the subscriber data, to the first transceiver 311a in a processing method different from that of the upstream data, thereby providing a broadband network. Downlink data is delivered to

Here, the network interface unit 311 is controlled by the control and management unit 312 connected to the network management unit 320 to perform the transmission and reception of ADSL data.

On the other hand, the downlink data cells coming into the cell bus are multiplexed on the cell bus and then transferred to the corresponding subscriber board in the subscriber board unit 313, and the corresponding subscriber board processes this to the analog phone separation unit 340. The downlink data is transmitted. Here, the subscriber board will be described in more detail as follows.

The subscriber board unit 313 is provided with a plurality of subscriber boards (ADSL-LT) as shown in Figure 3, one of the ADSL subscriber board, as shown in Figure 2 attached to the cell bus 360 A cell bus interface control unit 313a for multiplexing and demultiplexing ATM cells; A cell multiplexing service that is published between the cell bus interface controller 313a and the ATM handler 313c at the next stage and multiplexes and demultiplexes a cell stream transmitted and received between the cell bus interface controller 313a and the ATM handler 313c. / Demultiplexer 313b; The ATM handler (313c) for inserting and removing idle cells of the transmitted and received ATM cells, scramble and descramble cell payload, cell processing, HEC checking and generation, and converting an ATM utopia interface to a modem byte interface; An ADSL transceiver (313d) for demodulating the ATM cell delivered from the ATM handler (313c) and modulating the ATM cell delivered from the subscriber side; A line driver 313e disposed between the ADSL transceiver 313d and the analog telephone separation unit 340 to perform a line interface; Multiplexing / demultiplexing control of the cell bus interface control unit 313a, cell stream multiplexing / demultiplexing control of the cell multiplexing / demultiplexing unit 313b, cell processing control of the ATM handler 313c, and the ADSL transceiver 313d And a microprocessor 313f in charge of modulation / demodulation control.

The subscriber board configured as described above is multiplexed by the cell bus interface controller 313a on the cell bus and transferred to the cell multiplexer / demultiplexer 313b.

The cell multiplexer / demultiplexer 313b demultiplexes one cell stream into four cell streams in order to accommodate the four-subscriber interface in one board, and demultiplexes the demultiplexed cell into an ATM handler ( 313c).

The ATM handler 313c removes the Idel cells of the demultiplexed cells, descrambles the cell payload, performs cell descriptions, performs HEC checks and simultaneously performs ATM control under the control of the microprocessor 313f. It will convert the utopia interface to the modem byte interface.

In addition, the ADSL transceiver 313d forms an ADSL frame of the ATM cell delivered from the ATM handler 313c, demodulates the original data, and delivers the original data to the line driver 313e. The line driver 313e receives the analog signal. Transfer to the phone separator 340.

The analog phone separating unit 340 mixes the transmitted downlink data and the analog phone data transmitted from the public telephone network switch 33 and transmits the same to the subscriber through the existing twisted pair 400.

On the other hand, the uplink data and the analog phone data transmitted from the subscriber side is transmitted to the analog telephone splitter 340 in the central station 300 through the twisted pair 400, the analog telephone splitter 340 is transmitted The analog telephone is separated from the ADSL data and transferred to the public telephone network switch 330 so that the telephone service is performed through the PSTN 200 as before.

In addition, the separated ADSL upstream data is transmitted to the subscriber board 313 and is delivered to the ADSL transceiver 313d through the line driver 313e.

The ADSL transceiver 313d modulates the transmitted uplink data and delivers the data to the ATM handler 313c. The ATM handler 313c inserts an Idle cell into the delivered subscriber cell and scrambles the cell payload. After generating the HEC, the cell is processed and then transferred to the cell multiplexer / demultiplexer 313b.

Then, the cell multiplexing / demultiplexing unit 313b multiplexes four subscriber cells into one data in order to accommodate the four subscriber interface in one board, and then transfers the cells to the cell bus interface control unit 313a. It is mounted on the cell bus 360 by the interface controller 313a.

Such downlink data is processed in the reverse order as described above and is transmitted to the data exchange network unit 100 through the network interface unit 311 under the control of the network management unit 320.

The network access device according to the present invention having the above-described function is described by applying only to the ADSL broadband network access system. However, the present invention is not limited thereto. It is applicable to all systems having one broadband access link such as digital subscriber access equipment such as Carrier) and broadband access equipment such as ATM Concentrator / Multiplexer.

As described above, the present invention has the advantage that the ADSL network connection device can be configured in a self unit or a rack unit according to the number of subscribers, thereby improving the efficiency and economic efficiency of the overall network access system.

In addition, there is an advantage that it can be applied to not only ADSL network access system but also a system having one broadband access link.

Claims (6)

In an ADSL broadband service system having an ADSL network connection unit for switching between high speed data obtained from an ATM switch and an analog telephone obtained from a public telephone network, an ADSL network management unit, and a central station including a public telephone network switch and an analog telephone separation unit, The ADSL network connection portion, A network interface unit connected to the ATM switch and controlling an interface of uplink data and downlink data; A control and management unit that interfaces control and management information through the ADSL network management unit and an Ethernet interface and provides a control line interface for system initialization, configuration, and control through a serial interface; The downlink data transmitted through the network interface unit is controlled by the control and management unit to be demultiplexed and transmitted to the subscriber side, and only the ATM cell is extracted and multiplexed from the upstream data transferred from the analog phone separation unit to the network interface unit. Network access device in the DS broadband service network, characterized in that consisting of a subscriber board portion consisting of a plurality of ADSL subscriber board to deliver. In an ADSL broadband service system having an ADSL network connection unit for switching between high speed data obtained from an ATM switch and an analog telephone obtained from a public telephone network, an ADSL network management unit, and a central station including a public telephone network switch and an analog telephone separation unit, The ADSL network connection portion, A network interface unit connected to the ATM switch and controlling an interface of uplink data and downlink data; A control and management unit that interfaces control and management information through the ADSL network management unit and an Ethernet interface and provides a control line interface for system initialization, configuration, and control through a serial interface; The downlink data transmitted through the network interface unit is controlled by the control and management unit to be demultiplexed and transmitted to the subscriber side, and only the ATM cell is extracted and multiplexed from the upstream data transferred from the analog phone separation unit to the network interface unit. A network access device in an DSL broadband service network, characterized in that the self-made consisting of a plurality of self-made portion consisting of a plurality of subscriber board including a plurality of ADSL subscriber board to deliver. The method of claim 2, wherein the self portion, It consists of a master self to directly interface data to the data network and a plurality of general self to transmit and receive data with the master self, the master self and the general self is connected to a ring-like structure to interface the data Network access device in broadband service network. The method of claim 2, wherein the ADSL subscriber board, A cell bus interface controller for multiplexing and demultiplexing ATM cells on a cell bus; A cell multiplexing / demultiplexing unit which is provided between the cell bus interface control unit and an ATM handler at a later stage to multiplex and demultiplex cell streams transmitted and received between the cell bus interface control unit and the ATM handler; The ATM handler for inserting and removing idle cells of the transmitted and received ATM cells, scramble and descramble cell payload, cell processing, HEC checking and generation, and converting an ATM utopia interface to a modem byte interface; An ADSL transceiver for demodulating the ATM cell delivered from the ATM handler and demodulating the ATM cell delivered from the subscriber side; A line driver interposed between the ADSL transceiver and the analog telephone separator to perform a line interface; A microprocessor for multiplexing / demultiplexing control of the cell bus interface control unit, cell stream multiplexing / demultiplexing control of the cell multiplexing / demultiplexing unit, cell processing control of the ATM handler, and modulation / demodulation control of the ADSL transceiver. Network access device in the DS broadband service network, characterized in that. The method of claim 2, wherein the network interface unit, A first transceiver connected to a broadband network and interfacing an ADSL frame through a 45 Mbps T3 or 155 Mbps OC-3c interface; A first user network processor connected to the first transceiver and extracting only an ATM cell from a downlink or uplink data frame of T3 or OC-3c; Demultiplex the ATM cells extracted from the first user network processor, multiplex ATM cells of uplink data, and deliver only cells for the corresponding subscriber self to the cell bus interface, and cells for other subscriber self are the other subscriber self. A cell multiplexer / demultiplexer for transmitting to the side; A cell bus interface controller which delivers the demultiplexed subscriber cells in the cell multiplexer / demultiplexer to a cell bus and delivers the subscriber cells via the cell bus to the cell multiplexer / demultiplexer; The cell delivered to the other subscriber self side obtained in the cell multiplexing / demultiplexing unit is delivered to the second transceiver, and only the ATM cell is extracted from the uplink data of the other subscriber self side delivered through the second transceiver to the cell multiplexing / demultiplexing. A second user network processor for delivering to the multiplexer; The other subscriber cell obtained from the second user network processor transmits to another subscriber self side through a ring-type interface, and the subscriber data transferred from the other subscriber self side is composed of a second transceiver to deliver to the second user network processor. Network access device in the DS broadband service network. The method of claim 5, wherein the cell multiplexing / demultiplexing unit, A first-in, first-out (first-in, first-out) unit for first-in first-out of a downlink subscriber cell obtained from the first user network processor; A cell demultiplexer for demultiplexing subscriber cells obtained from the first first-in-first-out machine; A second first-in, first-out first-in, first-out of the demultiplexed cell obtained from the cell demultiplexer and delivered to the subscriber side connected to the self; A third first-in, first-out (first-in, first-out) unit for first-in first-out of the demultiplexed cell obtained from the cell demultiplexer and delivering it to another subscriber self; A fourth first-in, first-out-first-out to first-in, first-out subscriber cell connected to its self obtained from the cell bus interface controller; A first-in, first-out-first-out to first-in, first-out the subscriber cell delivered from the other subscriber self side obtained from the second user network processor; A cell multiplexer for multiplexing subscriber cells respectively obtained by the fourth and fifth first-in-first-out machines; And a sixth first-in, first-out (first-in, first-out) unit for first-in first-out of the subscriber cells multiplexed in the cell multiplexer and delivering the first-user first-time network to the first user network processor.