KR100374720B1 - Remote dslam system - Google Patents

Abstract

The present invention relates to a remote DSLAM (Digital Subscriber Loop Access and Multiplexing) system, and more particularly, to provide a high-speed bandwidth application to an ADSL network including a main DSLAM unit installed in a telephone station and a remote DSLAM unit installed at a predetermined distance from the main DSLAM unit. A remote digital subscriber line access transfer multiplexer (DSLAM) system, wherein the main DSLAM unit includes a Control Remote Interface Block (CRIB) for interfacing from the main DSLAM unit to the remote DSLAM unit, and the remote DSLAM unit is remote from the CRIB unit. A remote DSLAM system is characterized in that it comprises a MRIB unit (Modem Remote Interface Block) and ADSL modem unit to provide ADSL service to the subscriber ADSL modem in the present invention, the present invention is a non-uniform feature of the existing telephone network communication line Speed of ADSL service As well as to improve as much as possible and provide a remarkable effect that can reduce the overall cost of service.

Description

Remote DSLAM System {REMOTE DSLAM SYSTEM}

The present invention relates to a remote DSLAM system, and more particularly, by introducing a remote DSLAM unit at a certain distance from a telephone station, to prevent the speed drop due to the non-uniform characteristics and distance of the existing telephone network communication line to provide the maximum speed ADSL service It relates to a remote DSLAM system that can reduce service costs.

FTTH (Fiber To The Home) was selected as a technology for accessing broadband network, but it takes much time and cost to realize FTTH, so it is more inexpensive to use existing public telephone network before establishing subscriber network based on optical cable. Various modulation and demodulation technologies are being studied that can provide broadband services at cost. One of these is Asymmetric Digital Subscriber Line (ADSL) technology, which is an asymmetrical system that transmits 1.5 Mbps (or 6 Mbps) signals to subscribers in the network and slow control signals from the subscribers to the network side. It has been developed to have a transmission and reception speed structure.

1 is a schematic diagram of a conventional ADSL system. As shown in Fig. 1, this conventional ADSL system is installed in a telephone station to provide ADSL service to each subscriber through a telephone line. In these ADSL systems, splitters separate the low frequency components below 4KHz used for telephone voice and the high frequency bands used by ADSL modems to modulate data signals in order to enable high-speed data communication and telephone at the same time. 22) The splitter 22 is connected to both ends of the copper wire cable. On the other hand, a modem in a telephone station is mainly used a collective modem product having a multiplexing function called Digital Subscriber Loop Access and Multiplexing (DSLAM) 20. The DSLAM 20 is a device that connects an Asynchronous Transfer Mode Network (ATM) network and a Public Switched Telephone Network (PSTN). For example, a device having a function of transmitting to a router). The DSLAM 20 includes a plurality of ADSL modems 21 and a multiplexer 23, and includes an ATM switch 10, a PSTN switch 40, and a network management system (NMS) 50. Connected. In order to use the ADSL service, the subscriber modem 30 must also have an ADSL modem 31, and in some cases, the splitter 32 may be built in the modem of the subscriber.

As described above, in order to provide an existing ADSL service, a DSLAM (Digital Subscriber Loop Access and Multiplexing) equipment is provided to a telephone company to serve ADSL using a copper line between subscribers. Since it is installed to service existing telephones, it is widely distributed from 1 to 5 km. ADSL service can transmit information at high speed by using existing telephone line, and has the advantage of transmitting and receiving voice and data at the same time, whereas ADSL has 0 voice information area of general modem to transmit information at high speed. Use a frequency bandwidth higher than the bandwidth of ˜4 KHz. The higher the frequency, the higher the transmission speed, but the higher the transmission rate, the greater the signal loss and the shorter the transmission distance. Due to this situation, there are many differences in service speed for each subscriber in case of ADSL service, and the subscriber may not be able to receive ADSL service at all due to deterioration of line characteristics due to distance.

Furthermore, the actual ADSL system is because the characteristics of the telephone line, UTP (Unshielded Twisted Pair) cable, which KT has been installing in Korea for decades, is not constant and the area managed by the telephone company is more than several tens of kilometers depending on the region. Overall quality of ADSL service is deteriorating because it cannot support the maximum speed.

In order to solve this problem, there is a method of establishing a relay system such as an optical subscriber network among subscribers that are separated from a telephone station by a certain distance. However, in order to construct an optical subscriber network, a new optical cable has to be constructed, so additional costs are incurred. The implementation of equipment is difficult.

An object of the present invention is to overcome the problems of the prior art described above, and to solve the service degradation problem occurring in the ADSL service through the existing telephone network, xDSL IMA using the existing copper wire instead of the WAN interface. To provide a remote DSLAM system with a high speed serial interface using Inverse Multiplexing for ATM.

That is, the present invention for achieving the above object is a DSLAM (Digital Subscriber Line) to support high-speed bandwidth applications in the ADSL network including a main DSLAM unit installed in a telephone station and a remote DSLAM unit installed at a certain distance away from the main DSLAM unit As an Access Transfer Multiplexer) system,

The main DSLAM unit includes a CRIB unit (Control Remote Interface Block) for interfacing from the main DSLAM unit to the remote DSLAM unit,

The remote DSLAM unit provides a remote DSLAM system comprising an MRIB unit (Modem Remote Interface Block) for providing ADSL service from the CRIB unit to the subscriber ADSL modem in the remote area and an ADSL modem unit connected to the MRIB unit. .

1 is a schematic diagram of a conventional ADSL system,

2 is a schematic diagram of an ADSL system to which a remote DSLAM of the present invention is applied;

3 is a detailed block diagram of a remote DSLAM system of the present invention;

Figure 4 is a block diagram of an ADSL system shelf and rack applying a remote DSLAM system of the present invention.

* Description of the symbols for the main parts of the drawings *

100: ADSL modem unit 110: ADSL modem

120: first ATM serial input and output interface unit 130: first microprocessor

210: second ATM serial input / output interface unit 200: MRIB unit

220: ATM cell multiplexing / demultiplexing control unit 230: remote interface unit

300: CRIB unit 310: main interface unit

320: third ATM serial input / output interface unit 330: second microprocessor

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

2 is a schematic diagram of an ADSL system to which a remote DSLAM of the present invention is applied. As shown in Fig. 2, the present invention hypothesizes that the remote DSLAM unit 50, which is interfaced with the main DSLAM unit 700 installed in the telephone station, is located at a distance away from the telephone station by a predetermined distance (for example, 2 km or more), It is characterized in that the serial ATM packet of the high speed and constant delivery from the telephone station, and the data transmitted so far to the small remote DSLAM unit 50 to improve the ADSL service speed and lower the overall service cost.

2, the remote DSLAM system of the present invention is composed of a main DSLAM unit 700 and a remote DSLAM unit 50, the main DSLAM unit 700 is called a Remote Control Interface (Control Remote Interface Block, hereinafter referred to as CRIB). 300, and the remote DSLAM unit 50 includes an ADSL modem unit 100 and a remote modem interface unit (hereinafter referred to as a MRIB unit) 200, and includes a main DSLAM unit 700. And an interface between the remote DSLAM unit 50.

3 is a detailed block diagram of a remote DSLAM system in accordance with the present invention. 3, in the remote DSLAM unit 50 of the present invention, the ADSL modem unit 100 includes a plurality of ADSL modems 110 and a first ATM serial input / output interface unit for transmitting / receiving ADSL data as high speed serial data ( 120, and a first microprocessor 130 that controls various functional blocks within the board thereof.

Modem Remote Interface Block (MRIB) 200 in the remote DSLAM unit 50 of the present invention is responsible for providing ADSL service from the CRIB unit 300 to the ADSL modem in the area several kilometers away from the various interfaces. Specifically, the MRIB unit 200 is a second ATM serial input and output interface unit 210 for transmitting and receiving ADSL data from the ADSL modem unit 100 as high-speed serial data, the interface according to the remote method from the CRIB unit 300 Remote interface unit 230 that provides an interface capable of accommodating this, and sorts the ATM CELL data received through these remote interface unit 230 into blocks with ADSL modem chips and recovers ATM packet errors. ATM cell multiplexing / demultiplexing control unit 220 to perform the function. In the present invention, the remote interface unit 230 is an E1 interface unit (2Kbps-2.5Kbps), DS-3 interface unit (45Mbps) or STM-1 alternatively according to the interface type according to the remote method from the CRIB unit 300 (Synchronous Transport Module level-1) may be implemented in one of the interface unit (155Mbps).

In the remote DSLAM system of the present invention, the CRIB unit 300 controls various interface units while performing a high-speed serial interface function to interface from the main DSLAM unit 700 to a low voltage differential signaling (LVDS) in a telephone station. (E1, DS-3, STM-1). LVDS is a method that multiplexes data from multiple lines into a few high speed lines while reducing EMI. Specifically, the CRIB unit 300 includes a main interface unit 310 that provides various interfaces for performing a remote function, a third ATM serial input / output interface 320 for transmitting and receiving ADSL data as high speed serial data, and And a second microprocessor 330 that controls various functional blocks within their board. When the LVDS serial ATM packet method is used as in the present invention, the main interface 310 is manufactured as a module and implemented as one of an E1 interface unit, a DS-3 interface unit, or an STM-1 interface unit according to a remote type. Can be.

Hereinafter will be described the operation of the remote DSLAM system of the present invention. In the DSLAM system of the present invention, the CRIB unit 300 in the main DSLAM unit 700 performs a high-speed serial interface when the remote DSLAM unit 50 is applied to the high-speed main DSLAM unit 700 while providing various interfaces (E1, DS-3, STM-1), specifically, while the operation is controlled by the second microprocessor 330, the high speed serial data is received through the third ATM serial input / output interface unit 320 and the main The interface unit 310 provides various interfaces according to the remote type. The MRIB unit 200 of the remote DSLAM unit 50 provides an interface function with the main DSLAM unit 700 corresponding to the remote method of the CRIB unit 300 of the main DSLAM unit 700. That is, the remote interface unit 230 provides an interface capable of accommodating the remote interface unit 230 according to the interface type of the main interface unit 310 and transfers the data to the ATM cell multiplexing / demultiplexing control unit 220. . The ATM cell multiplexing / demultiplexing control unit 220 aligns the ATM CELL data received through the remote interface unit 230 into blocks with ADSL modem chips and recovers ATM packet errors so that two or more second ATM serial input / output interfaces are provided. Transmit to unit 210. The second ATM serial input / output interface 210 transmits and receives ADSL data to and from the ADSL modem unit 100 as high speed serial data. The multiple ADSL modems 110 of the ADSL modem unit 100 in the remote DSLAM unit 50 are controlled from the second ATM serial input / output interface 210 of the MRIB unit 200 under the control of the first microprocessor 130. ADSL modulates and demodulates the data received through the first ATM serial input / output interface unit 120. Data over the ADSL modem is sent to the subscriber modem via the splitter. In the above description, for convenience of description, the phone station has been described mainly for data processing in the direction of the subscriber. However, when data is transmitted upward from the subscriber, the phone station may be processed in the opposite direction as described above.

Figure 4 is a block diagram of an ADSL system shelf and rack applying a remote DSLAM system of the present invention. In FIG. 4, the AMSL (ADSL Modem Interface Block) corresponds to the ADSL modem unit of the DSLAM system of the present invention, and the MICB (Main Interface Control Block) performs the function of controlling the overall operation of the ADSL system shelf and rack in actual application. do.

According to the present invention, ADSL is constructed by constructing a remote DSLAM unit interfaced with a main DSLAM unit installed in a telephone station at a distance apart from the telephone station by a predetermined distance (for example, 2 km or more). The effect of speeding up the service as much as possible and reducing the overall service cost can be obtained.

Claims (7)

A Digital Subscriber Line Access Transfer Multiplexer (DSLAM) system supporting high-speed bandwidth applications in an ADSL network including a main DSLAM unit installed in a telephone station and a remote DSLAM unit installed at a predetermined distance from the main DSLAM unit. The main DSLAM unit includes a CRIB unit (Control Remote Interface Block) for interfacing from the main DSLAM unit to the remote DSLAM unit, And the remote DSLAM unit comprises a Modem Remote Interface Block (MRIB) providing an ADSL service from the CRIB unit to a subscriber ADSL modem located at a remote location and an ADSL modem unit connected to the MRIB unit. The method of claim 1, wherein the CRIB portion A main interface unit providing various interfaces to provide a remote function; A third ATM serial input / output interface unit for interfacing from the main DSLAM unit in the telephone station; And A remote DSLAM system, characterized in that it comprises a second microprocessor for controlling the overall operation of the CRIB unit. 3. The remote DSLAM system of claim 2, wherein the main interface unit is one of an E1 interface unit, a DS-3 interface unit, or an STM-1 interface unit. 3. The remote DSLAM system of claim 2, wherein the CRIB unit performs a high speed serial interface function to interface from the main DSLAM unit to Low Voltage Differential Signaling (LVDS). The method of claim 1, wherein the ADSL modem unit Multiple ADSL modems; A first ATM serial input / output interface unit for transmitting and receiving ADSL data as high speed serial data; And A remote DSLAM system comprising a first microprocessor for controlling various functional blocks within their board. The method of claim 1, wherein the MRIB unit A plurality of second ATM serial input / output interface units for transmitting and receiving ADSL data from the ADSL modems; An ATM cell multiplexing / demultiplexing control unit for aligning the received ATM CELL data into blocks with ADSL modem chips and recovering an ATM packet error; And Remote DSLAM system, characterized in that it comprises a remote interface for providing an interface with the CRIB unit. 7. The remote DSLAM system of claim 6, wherein the remote interface unit is one of an E1 interface unit, a DS-3 interface unit, or an STM-1 interface unit.