WO2006058495A1

WO2006058495A1 - Digital subscriber line access multiplexer and subscriber access device

Info

Publication number: WO2006058495A1
Application number: PCT/CN2005/002059
Authority: WO
Inventors: Haijun Wu; Zhijun Qu; Yupeng Xiong
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2004-12-04
Filing date: 2005-11-30
Publication date: 2006-06-08
Also published as: CN100525508C; CN1784079A

Abstract

A digital subscriber line access multiplexer, in order to solve the problem in prior art that the digital subscriber line access multiplexer has the lower bandwidth and poor capability of integrated services. Digital subscriber line access multiplexer in accordance to the present invention is configured based on the specific length packet bus and Ethernet exchange bus; digital subscriber line access multiplexer configured by specific length packet bus includes at least specific length packet interface module, the specific length packet bus connected with the module and the interface board connected with the bus; it is able to generate digital subscriber line access multiplexer that can meet various requirement based on this structure. Digital subscriber line access multiplexer based on Ethernet exchange bus includes at least Ethernet exchange module, the high speed or low speed Ethernet exchange bus connected with the module and the interface board connected with the bus; it is able to generate digital subscriber line access multiplexer that can meet various requirement based on this structure.

Description

Digital subscriber line access multiplexer and user access equipment

Technical field

The present invention relates to access technologies in the field of communications, and more particularly to a digital subscriber line access multiplexer and user access equipment.

Background technique

With the use of twisted pair access technology represented by asymmetric subscriber digital subscriber line (ADSL) on a global scale, digital subscriber line access multiplexer (DSLAM) products have gradually matured. According to the choice of the operator in the network solution and operation mode, the DSLAM products include the Asynchronous Transfer Mode (ATM) DSLAM and the IP DSLAM. In the device technical solution, the DSLAM device adopts the ATM bus or Ethernet on the backplane. The bus realizes the data transmission between the boards, which are respectively converted into ATM or IP data format and forwarded to the network side interface. The ATM DSLAM device provides an ATM network side interface, and the DP DSLAM device provides an IP network side interface. On the user side, the DSLAM device provides ADSL, VDSL, and single-pair high-speed digital subscriber line (SHDSL) interfaces. When ADSL and VDSL interfaces are provided, the DSLAM will simultaneously use voice separation technology to implement the user's analog phone. Ordinary old telephone service (POTS) interface, with the development of xDSL technology, DSLAM equipment can also provide other DSL interfaces such as ADSL2, ADSL2+, VDSL2. For ATM DSLAM devices, the ATM technology can also fully utilize the characteristics of multi-service bearer, and provide multiple service types such as circuit emulation service (CES) and frame relay (FR) access.

Taking ADSL as an example, the entire access system consists of a central office device (DSLAM), a client device, a splitter, and a management system. The basic configuration of the ADSL system is shown in Figure 1. ,

The different types of Service Node Interfaces (SNIs) in the ADSL system determine the different DSLAM types, namely, Ding]\ 081^]^ and 1? 081^]^. The splitter isolates the POTS/ISDN band signal and the ADSL band signal so that POTS/ISDN services and ADSL data services can be transmitted simultaneously and unaffected on the same twisted pair. The ADSL management unit can manage ADSL devices in an out-of-band (OB) mode or in-band (IB) mode.

Since the most widely used ADSL technology was born, it was combined with ATM technology. Therefore, the construction of DSLAM equipment using ATM technology is the most common and mature technical solution. As shown in FIG. 2, the DSLAM device is composed of different boards or function modules, and generally includes a main control module, a management communication module, an uplink interface module, a service processing module, etc., wherein the main control module, the management communication module, and the uplink interface module can be It is a physically separate board or a unified board. When the ATM technology solution is adopted, the ATM bus is used in the DSLAM system to implement service data forwarding between modules.

Each interface module or board in the DSLAM system is connected through an ATM bus distributed on the backplane. The interworking between the user-side interface modules and the uplink interface modules is implemented in the system through a permanent virtual channel (PVC) connection. The SNI interface type provided by the uplink interface module determines the type of the DSLAM. When the SNI interface is an ATM interface, the DSLAM device is an ATM DSLAM. The service interface between the ATM and the IP can also be implemented in the uplink interface module to form an IP. DSLAM device.

The user interface module includes xDSL service interfaces such as ADSL, VDSL, and SHDSL. For the ATM DSLAM device, ATM service interfaces such as CES and FR can also be provided. In addition, the ATM cascade module in the DSLAM is also connected to the system through the ATM bus. . In the system, the processing of services with high processing performance requirements can be realized by adding a dedicated service processing module.

In such a DSLAM system, the ATM bus is the transmission channel of all services and is the basic bus of the system. In addition, there may be some auxiliary buses in the system, such as a communication bus for carrying control messages between modules, for connecting. Test bus for external test instruments, etc.

The DSLAM device shown in Figure 2 has the following disadvantages:

(1) ATM bus bandwidth is generally narrow, common rate grades such as 155M, 622M, higher performance ATM bus bandwidth can reach 1.2G, 2.5G rate grade, these bandwidths are shared by the entire DSLAM system, the bandwidth of the entire DSLAM system Limited by the bandwidth of the ATM bus, the performance is low, and the bandwidth to each user interface module is low, which is difficult to adapt to the rapid development of broadband access requirements;

(2) From a technical point of view, although an ATM switching network can be used to build a large-capacity ATM backplane system, as shown in Figure 3, in reality, the expensive ATM switching network structure makes such a DSLAM system impossible to obtain practical applications. A DSLAM device that directly accesses a user must use an inexpensive system structure. (3) The business service shield (QOS) support capacity is insufficient. In the ATM structure of the DSLAM system, the ATM PVC is used for internal connection between the uplink interface and the user interface, and the PVC-based data traffic and priority control are required through the ATM Quality of Service (QOS) mechanism. In fact, the user's service is directly In the IP service type, in general, each user uses a single PVC connection to access the DSLAM system, so that different QOS guarantees cannot be provided for different service types in the PVC in the DSLAM system. Of course, you can consider using different PVC access for each service, but this will cause the number of PVCs to increase exponentially, which brings additional complexity to network data configuration and management.

(4) Insufficient multicast support. The DSLAM system based on the ATM architecture generally uses the point-to-multipoint (PTMP) PVC method to support multicast services, and there is no perfect solution for the multicast service.

In response to the growing demand for IP DSLAM applications, a DSLAM device built using Ethernet technology has emerged, as shown in Figure 4. The DSLAM system uses an Ethernet switch fabric, and the backplane distributes the Ethernet bus. The Ethernet switch technology enables interworking between the device service interface and the uplink interface. The ATM-based xDSL access technology, such as ADSL, implements the adaptation between ATM and Ethernet in the device interface module, and converts the Ethernet packet into the system backplane. The core component of the system is an Ethernet switch module. This module implements functions such as packet exchange, uplink forwarding, and service flow processing, and provides an uplink Ethernet SNI interface.

Although the DSLAM device shown in FIG. 4 is compared with the ATM-based DSLAM device, the IP DSLAM device of the Ethernet architecture is more suitable for the development trend of the current backbone network IP, and is a newer type of DSLAM device, but it also has its inherent Disadvantages:

(1) Not suitable for ATM network structure. Although the development trend of IP network of backbone networks is obvious, the scale of ATM networks is still very large. Especially for some traditional operators, the ATM network construction is quite complete, and it undertakes the work of large-scale broadband network operation. Some ATM backbones The network still has capacity expansion, and many DSLAM construction still needs to access the ATM network. The DSLAM products of the Ethernet architecture generally do not have an ATM interface, or need to perform protocol conversion multiple times to provide an ATM interface, and the processing efficiency is low.

(2) Comprehensive services cannot be provided. Carrying integrated services is another advantage of the ATM architecture, and Ethernet-based DSLAM equipment cannot implement multi-service support based on ATM technology, such as frames. Relay (FR) services, circuit emulation services (CES), and these services are also important to protect operators' existing network investments.

(3) The system bandwidth is low and the service support capability is still weak. In a DSLAM system with an Ethernet architecture, a low-speed Ethernet bus is usually used to implement the connection between service interface modules. The bandwidth of a single module interface is generally less than 100M, and the average user interface bandwidth is still low, supporting large-capacity multicast services and high bandwidth. The ability of the business is also very limited.

In summary, existing DSLAM devices have disadvantages such as lower bandwidth and poor overall service capabilities. Summary of the invention

The present invention provides a digital subscriber line access multiplexer and a user access device to solve the problem that the existing access equipment has a low bandwidth and a poor integrated service capability.

In order to solve the above problems, the present invention provides the following technical solutions:

A digital subscriber line access multiplexer includes: a system module that provides an uplink interface, a service interface board that provides a service interface, and a system bus that connects the system module and the service interface board; wherein: the system module includes at least a fixed length package An interface module, configured to implement a bus interface and a service processing; the system bus includes a fixed length packet switching bus connected to the fixed length packet interface module; the service interface board includes a first connection with the fixed length packet switching bus An interface board.

The system module further includes an Ethernet adapter module connected to the fixed length packet interface module, the Ethernet adapter module having an IP uplink interface.

The system module further includes an Ethernet adapter module connected to the fixed length packet interface module, and an Ethernet switch module connected to the Ethernet adapter module, the Ethernet switch module having an IP uplink interface. The system bus further includes a high speed Ethernet switching bus coupled to the Ethernet switching module; the service interface board further comprising a third interface board coupled to the high speed Ethernet switching bus.

The system bus also includes a low speed Ethernet switching bus coupled to the Ethernet switching module; the service interface board further includes a fourth interface board coupled to the low speed Ethernet switching bus.

The system module further includes a multicast processing module connected to the Ethernet switching module; the system bus further includes a high speed multicast bus connected to the multicast processing module; The port board also includes a fifth interface coupled to the high speed multicast bus and the low speed Ethernet switch bus.

The system bus further includes a fixed length packet multicast bus connected to the fixed length packet interface module, and the service interface board further includes a second connection with the fixed length packet multicast bus and the fixed length packet switching bus The interface board; and/or the system module further includes an ATM uplink processing module connected to the fixed length packet interface module, the ATM uplink processing module having an ATM uplink interface.

A digital subscriber line access multiplexer includes: a system module providing an uplink interface, a service interface board providing a service interface, and a system bus connecting the system module and the service interface board; wherein: the system module includes at least an IP An Ethernet switch module of an uplink interface; the system bus includes a high speed Ethernet bus connected to the Ethernet switch module, or/and a low speed Ethernet switch bus; the service interface board includes a connection with the high speed Ethernet bus a third interface board, or/and a fourth interface board connected to the low speed Ethernet switching bus.

The system module further includes an Ethernet adapter module connected to the Ethernet switch module, and a fixed length packet interface module connected to the Ethernet adapter module; the system bus further includes a connection with the fixed length packet interface module The fixed length packet switching bus; the service interface board further includes a first interface board connected to the fixed length packet switching bus.

The system module further includes a multicast processing module connected to the Ethernet switching module, the system bus further includes a high speed multicast bus connected to the multicast processing module, and the service interface board further includes a high speed multicast bus connection or a fifth interface board connected to the high speed multicast bus and the low speed Ethernet switch bus; and/or the system module further includes an ATM uplink module connected to the fixed length packet switch module .

A user access device, including a main frame and a slave frame; wherein:

The main frame includes: a system module, having an IP uplink interface and/or an Asynchronous Transfer Mode (ATM) uplink interface, used for device, interface management, bus control, and service processing; a service interface board for providing a service interface; The system module and the service interface board are connected to transmit a data packet; the slave frame includes: a service interface board, configured to provide a service interface; a system bus, connected to the service interface board; Cascade from the box.

The first broadband user access system provided by the present invention comprises an ATM network, an ATM access/switching device connected to the ATM '-network, and the ATM access/switching device through a connection network a connected access multiplexer and a user equipment connected to the access multiplexer, wherein the access multiplexer includes: a system module that provides an uplink interface, a service interface board that provides a service interface, and a system bus that connects the system module to the service interface board;

The system module includes at least a fixed length packet interface module for implementing a bus interface and service processing,

The system bus includes a fixed length packet switching bus connected to the fixed length packet interface module; the service interface board includes a first interface board connected to the fixed length packet switching bus. The second broadband user access system provided by the present invention comprises an IP network, an IP access/switching/aggregation/routing device connected to the IP network, and the IP access/switching/aggregation/routing through the connection network An access multiplexing device connected to the device and a user device connected to the access multiplexing device, wherein the access multiplexing device includes: a system module that provides an uplink interface, and a service interface board that provides a service interface, And a system bus that connects the system module and the service interface board;

The system module includes at least a fixed length packet interface module for implementing a bus interface and service processing;

The system bus includes a fixed length packet switching bus connected to the fixed length packet interface module; the service interface board includes a first interface board connected to the fixed length packet replacement bus. The third broadband user access system provided by the present invention comprises an ATM network, an IP network, an IP access/switching/aggregation/routing device connected to the IP network, and an ATM access connected to the ATM network/ a switching device, connected to the ATM access/switching device by a connection network, and an access multiplexing device connected to the IP access/switching/aggregation/routing device and a user device connected to the access multiplexing device, The access multiplexing device includes: a system module that provides an uplink interface, a service interface board that provides a service interface, and a system bus that connects the system module and the service interface board;

The system bus includes a fixed length packet switching bus connected to the fixed length packet interface module; the service interface board includes a first interface board connected to the fixed length packet switching bus. The access multiplexing device may be an access multiplexing device network connected through a connection network. In the above three broadband user access systems, the system bus further includes a high-speed Ethernet switching bus connected to the Ethernet switching module; the service interface board further includes a third connection with the high-speed Ethernet switching bus. Interface board.

The system module further includes a multicast processing module connected to the Ethernet switching module; the system bus further includes a high speed multicast bus connected to the multicast processing module; the service interface board further includes A fifth interface board connected to the high speed multicast bus and the low speed Ethernet switch bus.

Compared with the prior art, the invention has the following beneficial effects:

1. The DSLAM of the present invention can provide various buses and corresponding service interfaces such as a high-speed multicast bus, a high-speed Ethernet switching bus, and a fixed-length packet switching bus, thereby comprehensively improving system bandwidth and user port bandwidth;

2. Since the DSLAM of the present invention has a high-speed multicast bus and a fixed-length packet multicast bus, it has stronger multicast capability than the existing DSLAM, and can improve service support capability;

3. The present invention can provide an IP uplink interface by an Ethernet switching module, so that the IP DSLAM of the present invention can utilize the technology to make a qualitative leap in service processing performance, for example, a user interface board capable of providing a gigabit rate;

4. Since the DSLAM of the present invention can provide an uplink interface on the ATM network side and an ATM service interface, it has comprehensive service capabilities.

DRAWINGS

1 is a schematic diagram of a basic configuration of an ADSL system in the prior art;

2 is a schematic structural diagram of a DSLAM using ATM technology in the prior art;

3 is a schematic diagram of a DSLAM structure using an ATM switching network structure in the prior art; FIG. 4 is a schematic diagram of a DSLAM structure constructed by using an Ethernet technology in the prior art; FIG. 5 to FIG. 11 are ATMs based on a fixed length packet bus architecture according to the present invention; Schematic diagram of the DSLAM structure; 12 to FIG. 16 are schematic diagrams showing the structure of an IP DSLAM based on an Ethernet framework according to the present invention; FIG. 17 is a schematic diagram of a DSLAM of the present invention through a fixed length packet bus;

18 is a schematic diagram of a DSLAM of the present invention being cascaded through a bus;

19 is a schematic diagram of a DSLAM of the present invention cascaded through an Ethernet;

20 is a schematic diagram of cascading DSLAMs in a networking according to the present invention;

21 is a block diagram of an embodiment of a first broadband user access system according to the present invention;

22 is a block diagram of an embodiment of a second broadband user access system of the present invention;

23 is a block diagram of an embodiment of a third broadband subscriber access system of the present invention;

24 is a block diagram of an embodiment of a fourth wideband subscriber access system of the present invention.

DETAILED DESCRIPTION OF THE INVENTION The Digital Subscriber Line Access Multiplexer (DSLAM) of the present invention includes a system module, a system bus, and a service interface board. The system module implements device management, interface management, bus control and service processing of the entire DSLAM. The system bus is an organic combination of various buses for different device functions and performance requirements to meet different DSLAM services and evolution requirements, and service interface boards. Available in accordance with the system bus type to meet different application and performance needs. The DSLAM of the present invention will be described in detail below with reference to the accompanying drawings.

Refer to the fixed-length packet bus-based Digital Subscriber Line Access Multiplexer (DSLAM) shown in Figure 5, which includes a system module that implements device management, interface management, bus control, and service processing for the entire DSLAM. In this structure, the system module includes: an ATM uplink processing module having an asynchronous transfer mode (ATM) uplink interface, and a fixed length packet interface module connected to the ATM uplink processing module. The system bus includes: a fixed length packet switching bus and a fixed length packet multicast bus connected to the fixed length packet interface module. The service interface board includes: a first interface board eight connected to the fixed length packet exchange bus.

The fixed length packet interface module implements the interface and service processing of the fixed length packet switching bus and the fixed length packet multicast bus, and is usually an ATM bus interface module, and the implementation method includes using a switched ATM bus controller or an ATM switching network.

The ATM uplink processing module implements the operation of the ATM user network (UNI) or the network-network interface (ΝΜ), and performs standard ATM encapsulation of the fixed-length packets in the system and provides an ATM uplink interface.

The fixed length packet switching bus can be of various bus types for use in system modules and service interfaces. Two-way exchange of fixed length messages between boards. Among these fixed length messages, the most typical one is

ATM cell. The fixed length packet switching bus includes, but is not limited to, a general-purpose test and operational physical connection (UTTOPIA) bus of ATM, a shared bus such as a cell bus (CELLBUS), an ATM serial bus, or a star bus. Through the fixed-length packet switching bus, the DSLAM device can have all the system functions of the DSLAM of the ATM architecture, and provides an ATM type service interface, an uplink interface, and a cascade interface. The fixed length packet switching bus in the DSLAM device can be one or more sets to meet different system performance requirements.

The fixed-length packet multicast bus can also be a variety of bus types through which multicast service processing based on fixed-length packet switching is implemented. The bus uses existing fixed-length packet bus signal definitions, including but not limited to ATM general-purpose test and operational physical interface (UTOPIA) bus, cell bus (CELLBUS), ATM serial bus, etc. shared bus or star bus, transmission One-way multicast service. Through this bus, the DSLAM device of the ATM architecture can be equipped with large-capacity multicast service support without changing the system function structure, and the service interface board only has the ATM layer function. The fixed-length packet multicast bus in the DSLAM device can be one or more sets to meet different system performance requirements.

The first interface board A is an interface board based on a fixed length packet switching bus. This type of board includes all the interface boards of the DSLAM device based on the ATM system. The functions implemented by these boards include providing access to XDSL services such as ADSL, SHDSL, and VDSL, and providing dedicated lines such as Ethernet, circuit emulation, and frame relay. Service access, providing ATM cascade interface of DSLAM. For the most widely used ADSL cards in a DSLAM device, all upstream and downstream traffic is transmitted through this fixed-length packet switching bus.

The DSLAM shown in FIG. 6 adds a fixed-length packet multicast bus to the structure shown in FIG. 5, and a second interface board B connected to the fixed-length packet multicast bus and the fixed-length packet switching bus.

The second interface board B is an interface board based on a fixed length packet switching bus and a fixed length packet multicast bus. On the interface of the backplane, the second interface board B is similar to the first interface board A, and is connected to the fixed length interface module in the system module, and is usually an ATM interface and a processing module. Only the ATM layer processing operation is performed on the second interface board B, and the Ethernet or upper layer services are not processed. The difference is that the interface board B has a multicast bus interface added to the interface board A. The multicast bus can achieve multicast service processing capability of several Gbit/s levels, so that the ATM-based DSLAM system satisfies the high-performance multicast service. Claim. In the second interface board B, since the large-flow multicast service is offloaded to the fixed-length packet multicast bus, the load of the fixed-length packet switching bus is alleviated, that is, the fixed-length packet bus can be more user interfaces. Sharing, therefore, the second interface board B can have a higher port density than the first interface board A.

Compared with the conventional ATM DSLAM, the DSLAM shown in FIG. 6 has a large-capacity fixed-length packet multicast bus, and the multicast service can be offloaded to the fixed-length packet multicast bus in the system, and the fixed-length packet exchange is performed. The bus carries normal data traffic, which improves the system performance and device capacity of the ATM DSLAM.

Referring to FIG. 7, the DSLAM is an ATM and IP DSLAM based on a fixed-length packet bus architecture. Compared with the DSLAM shown in FIG. 5, an Ethernet adapter connected to the fixed-length packet interface module is added to the system module. The module implements interface adaptation and network-side IP uplink interface through the Ethernet adapter module to implement IP service functions. The DSLAM device can directly provide an ATM uplink interface as an ATM DSLAM, or can provide an IP uplink interface as an IP DSLAM through Ethernet adaptation, and can also provide an ATM and an IP uplink interface.

Referring to FIG. 8, the DSLAM adds an Ethernet adapter module and an Ethernet switch module connected to the Ethernet adapter module based on the DSLAM structure shown in FIG. 6.

The Ethernet switch module is the core module of the system. It implements Ethernet switch bus control and service processing functions. The Ethernet switch module directly provides the system's IP uplink interface, and is especially suitable for use as a large-capacity DSLAM device.

The Ethernet adapter module implements protocol adaptation between the Ethernet switch module and the fixed-length packet interface module, and implements packet splitting and reassembly, protocol encapsulation, and cache forwarding between the Ethernet and ATM fixed-length cells. .

Referring to FIG. 9, the DSLAM adds an Ethernet high speed bus connected to the Ethernet switch module and a third interface board C connected to the bus on the basis of FIG.

The high speed Ethernet switching bus includes, but is not limited to, a 1000M Ethernet star bus,

Glink star bus or other high speed star Ethernet bus. The bus bandwidth is generally above 1000 Mbit/s. The interface bandwidth of each interface module in the DSLAM device is greatly improved by the high-speed Ethernet switching bus, and the Ethernet packet exchange between the ^^ port module and the system module is realized through the LAN SW module in the system module. The third interface board C is an interface board based on a high speed Ethernet switching bus. The high-speed Ethernet switching bus is a star-type high-bandwidth bus, and the interface board C is all implemented based on this bus. Ethernet service processing is realized by communicating with a large-capacity Ethernet switch module in the system module through a standard Ethernet interface. When the interface board C provides an interface such as ADSL, it needs to implement the adaptation of the ATM cell of the ADSL interface to the high-speed Ethernet switching bus of the backplane. The high-speed Ethernet switching bus has a high bandwidth and can reach more than 1000 Mbit/s, which fully guarantees that the interface board C of the high-density DSLAM system can achieve high port density. Interface board C can also be used as a higher bandwidth interface board, such as: fiber-to-the-home (FTTH) fiber access interface, or as other high-speed interfaces, or as other high-speed interfaces; another example: directly provide Gigabit Ethernet interface as The DSLAM uplink interface board provides a cascading interface as a DSLAM cascading aggregation board, and provides an RPR or MSTP transmission interface as a DSLAM networking interface board, and provides a broadband access server (BAS) function as a service processing board.

Referring to FIG. 10, the DSLAM adds a low-speed Ethernet switching bus connected to the Ethernet switching module and a fourth interface board D connected to the bus, based on the structure shown in FIG.

The low speed Ethernet switching bus includes, but is not limited to, a 100M Ethernet star bus. The low-speed Ethernet switching bus is a bus supported by the DSLAM device of the existing Ethernet architecture. The Ethernet switching module and the low-speed Ethernet bus in the system module enable Ethernet packet exchange between each interface module and the system module. The DSLAM device has this bus interface and can be fully functional, performance and business supported by the DSLAM device of the current Ethernet architecture.

The interface board D is an interface board based on a low-speed Ethernet switching bus. The boards include all interface boards of the current Ethernet-based DSLAM equipment, and provide XDSL service interfaces such as ADSL, SHDSL, and VDSL, and maintain the existing system. compatibility. These boards meet basic broadband access functions. However, due to the low interface bandwidth, they are generally 100 Mbit/s, and their service development capabilities are weak.

The high-speed Ethernet switching bus is the development and enhancement of the original low-speed Ethernet switching bus. In the system bus structure, the two can exist physically independently, or they can share the same physical bus through the Ethernet rate adaptive technology.

Referring to FIG. 11, the DSLAM adds a multicast processing module, a high-speed multicast bus connected to the multicast processing module, and a fifth interface connected to the high-speed multicast bus and the low-speed Ethernet bus. board. The DSLAM is a versatile (or fully compatible) DSLAM. The multicast processing module implements Ethernet multicast control and multicast packet copy and forwarding functions, and implements high-performance multicast service processing by using hardware replication technology.

The high-speed multicast bus is a broadband high-performance multicast bus, which satisfies the requirements of large-capacity multicast video services. The design of the high-speed multicast bus is generally the same as that of the high-speed Ethernet switching bus, and the star bus structure is used in the system module. The multicast processing service provides the multicast service for each interface module under the control of the broadcast processing module. The high-speed multicast bus can also implement multicast streaming using a shared bus. The main function of this bus is to cooperate with the low-speed Ethernet switching bus to improve the multicast performance of the DSLAM system.

The interface board E is an interface board based on a low speed Ethernet switching bus and a high speed multicast bus. The high-speed multicast bus can be implemented based on high-speed Ethernet technology, achieving a bandwidth of more than 1000 Mbit/s, enabling the system to have high-performance multicast service support capabilities. Because the high-speed multicast bus offloads the high-traffic multicast, the low-speed Ethernet switch bus is only used for the bearer of the interactive service (such as the Internet), so that the interface board E has a larger service support capability than the interface board D. Increase in range.

In the DSLAM structure shown in Figure 7, Figure 8, Figure 9, Figure 10, and Figure 11, there may be no

The ATM uplink module provides the IP uplink interface only by the Ethernet adapter module. Similarly, in these DSLAM structures, low-speed Ethernet switching, high-speed Ethernet switching bus, fixed-length packet switching bus, fixed-length packet multicast bus, high-speed multicast bus, and corresponding interface boards may be one or more sets, respectively. Meet different system performance requirements.

Referring to Figure 12, the DSLAM is based on a low-speed Ethernet switching bus to build IP.

DSLAM device. The system module includes an Ethernet switching module, and the system bus includes a low-speed Ethernet switching bus connected to the Ethernet switching module, and the service board includes a fourth interface board D connected to the bus. The functions and functions of the multicast processing module, the low-speed Ethernet switching bus, and the fourth interface board D are described above.

Referring to Figure 13, the DSLAM is based on a high-speed Ethernet switching bus to build an IP DSLAM device. The low-speed Ethernet switching bus of the DSLAM shown in Figure 12 is changed to a high-speed Ethernet switching bus, which improves the performance of the Ethernet bus in Figure 12. . The corresponding service board includes a third interface board C connected to the high speed Ethernet bus. The functions and functions of the high speed Ethernet switching bus and the third interface board C are as described above.

Of course, the DSLAM structure shown in FIG. 12 and FIG. 13 can also be integrated, that is, a DSLAM has both a low-speed and high-speed Ethernet switching bus and a corresponding interface board. Referring to FIG. 14, the DSLAM adds a multicast processing module connected to the Ethernet switching module to the system module based on the DSLAM structure shown in FIG. 12, and adds a high-speed connection to the multicast processing module in the system bus. The multicast bus adds a fifth interface board E connected to the high speed multicast bus and the low speed Ethernet switching bus in the service interface board.

Referring to FIG. 15, the DSLAM adds a high-speed Ethernet bus and a corresponding third interface board C connected to the Ethernet switching module based on the DSLAM structure shown in FIG.

Referring to FIG. 16, the DSLAM is based on the DSLAM structure shown in FIG. 15, and an Ethernet adapter module, a fixed-length packet interface module, and an ATM uplink module connected to the Ethernet switch module are added to the system module; the system bus is added. A fixed length packet switching bus connected to the fixed length packet interface module; the service interface board adds a first interface board A connected to the fixed length packet switching bus. Of course, there is no ATM uplink module as needed.

Each module in the above DSLAM device is divided into logical functions. In terms of implementation, it may exist on the same hardware board, or meet these requirements through different board combinations.

With the continuous development of chip and system design levels, the port density of DSLAM devices has been greatly improved compared to the time of birth, but the capacity of single-frame DSLAMs has always been limited. The system capacity of the current single-frame DSLAM equipment is generally 400-700 ports, and some high-density DSLAM equipment can reach 1000 ports. Even so, it is still not enough to meet the needs of large-capacity DSLAM site construction, so DSLAM must have multi-frame cascading capabilities to form a large-capacity DSLAM system. In addition, in order to save the port resources of the aggregation or backbone layer network equipment, the DSLAM equipment of multiple sites also needs to be connected to the upper layer network after the tandem connection. This tandem function is also often completed by the DSLAM itself, which requires the DSLAM equipment to be level. Link function. The aforementioned DSLAM devices are available in a variety of cascading modes with different features, performances, and applications. The following describes several cascading modes:

Cascading mode one: fixed length packet bus cascade

Referring to FIG. 17, the entire access device includes a main frame and a slave frame, and the DSLAM device in the main frame can be directly cascaded through the fixed length packet bus extension. In this cascading mode, multi-frame cascading expansion of the DSLAM is achieved directly by extending the fixed length packet bus to the slave frame. In the extension of the fixed-length packet bus extension, the long-packet switching bus and the fixed-length packet multicast bus can be included to support common data services and multicast services, respectively. The fixed-length packet bus cascading mode can be used to carry out services based on interface board A and interface board B. It is suitable for XDSL access, ATM access services such as circuit emulation and frame relay, and ATM or IP network can be provided in the main frame. Side interface. Since the cascading is directly implemented by using the bus extension method, the cascading slave frame of the solution can adopt a simple control method, and the slave frame can be directly managed by the main frame without the centralized main control board. The fixed-length packet bus cascading mode is generally used in the case where the main frame is close to the frame and the number of frames is small.

In this cascading mode, the main frame and the slave frame may be any of the aforementioned DSLAM structures having a fixed length packet switching bus and or a fixed length packet multicast bus, respectively.

Cascading mode two: bus adaptation cascade

Referring to FIG. 18, a plurality of cascaded interfaces are extended by the Ethernet adapter module in the system module to perform multi-frame cascading. In this cascading mode, the fixed-length packet bus interface module and the Ethernet adaptation module are The interface between the two acts as an inter-frame cascade interface. This interface can be extended by long-distance transmission through a standard ATM interface or a self-defined internal interface inside the device through a transmission medium such as cable or fiber. Compared with the previous cascade solution, the bus adapter cascade scheme is greatly expanded. The distance between the master and the slave can be used as a multi-frame extension for a large-capacity office or as a slave to a remote DSLAM site.

In the same way as the fixed-length packet bus cascading scheme, in the bus-adaptive cascade mode, the slave frame still implements user access only through the fixed-length packet switching bus and the fixed-length packet multicast bus to support common data services and multicast respectively. The service can be based on the interface board A and the interface board B. It is suitable for the XDSL access service. The cascading slaves are connected to the Ethernet adapter module in the main frame system module. ATM service access such as circuit simulation and frame relay. This cascading mode is suitable for the IP DSLAM application mode, and provides an IP network side interface in the main frame.

The control module of the slave frame is simple in implementation, and only needs to realize the fixed-length packet bus interface, and converts into a system cascade interface and the master control interconnection, and realizes control from the frame business boards by communication with the master control.

In this cascading mode, the main frame and the slave frame may be any of the aforementioned adapter modules, respectively.

DSLAM structure.

Cascading mode three: Ethernet cascading

Referring to FIG. 19, in this cascading mode, multiple standard Ethernet interfaces can be extended through the Ethernet switch module in the main frame system module to be used as a slave cascade: an interface, which is realized by an Ethernet cable or an optical fiber. The distance transmission can be used as a multi-frame extension of a large-capacity office point, or access to a long-distance DSLAM office point through a frame. In this cascading mode, the slave chassis can support various service boards and is suitable for XDSL access services. Since the cascaded sub-frames use Ethernet cascade links, ATM service access such as circuit emulation and frame relay cannot be supported in the slave frame. This cascading mode is suitable for the IP DSLAM application mode, and provides an IP network side interface in the main frame.

In this cascading mode, the main frame and the slave frame may be any of the aforementioned DSLAM structures having an Ethernet switching module, respectively.

Figure 20 shows the cascading networking mode of the multiple structure DSLAMs of the present invention. Referring to the various structures described above, details are not described herein.

The various DSLAM devices provided by the present invention can meet the requirements of current large-scale network construction and the development of future broadband access technologies in various broadband access constructions, and can realize mature access technologies such as ADSL and emerging technologies. And future broadband access technology development requirements, such as ADSL2+, VDSL2 FTTP.

The DSLAM provided by the present invention, that is, the access multiplexing device, can cooperate with various networks and user equipments to form a broadband user access system, and constitutes multiple network construction modes.

21 is a block diagram of an embodiment of a first broadband subscriber access system of the present invention. In the embodiment system shown in FIG. 21, an ATM network, an ATM access/switching device connected to the ATM network, an access multiplexing device connected to the ATM access/switching device through a connection network, and The user equipment connected to the access multiplexing device. The access multiplexing device (the xDSL central office device) provides a DSL user interface through the user interface board and is connected to the xDSL user board. The user board providing the DSL interface may include the second interface board B, the third interface board C, and the fourth interface. Board D, fifth interface board E,. The ATM switch accesses the access network of the upper-layer ATM network through the ATM interface, and finally accesses the ATM network. Connection forms include, but are not limited to, chain, star, tree, ring topology, or a combination of these. The ATM interface of the xDSL central office device can be provided through the ATM uplink of the system module or the first interface board A.

22 is a block diagram of an embodiment of a second type of broadband subscriber access system of the present invention. In the embodiment system shown in FIG. 21, an IP network, an IP access/switching/aggregation/routing device connected to the IP network, and the IP access/switching/aggregation/routing device are connected through a connection network. And an access multiplexing device and a user equipment connected to the access multiplexing device. The access multiplexing device (xDSL central office device) provides a DSL user interface through the user interface board and is connected to the xDSL user board. The user board providing the DSL interface may include the second interface board B, the third interface board C, and the fourth interface. Board 0, fifth interface board E,. IP switching/connection to the upper IP network through the IP interface Incoming/aggregating/routing devices, eventually accessing the IP network. Connection forms include, but are not limited to, chain, star, tree, ring topology, or a combination of these. The IP interface of the xDSL central office device can directly provide an IP uplink interface through the IP uplink of the system module or the third interface board C, the fourth interface board D, or the fifth interface board E.

23 is a block diagram of an embodiment of a third wideband subscriber access system of the present invention. In the embodiment system shown in FIG. 21, an ATM network, an IP network, an IP access/switching/aggregation/routing device connected to the IP network, and an ATM access/switching device connected to the ATM network are included. Connecting to the ATM access/switching device and the access multiplexing device connected to the IP access/switching/aggregation/routing device and the user device connected to the access multiplexing device through a connection network The multiplexed device (xDSL central office device) provides a DSL user interface through the user interface board and is connected to the xDSL user board. The user board providing the DSL interface may include the second interface board B and the third interface board (:, the fourth interface board D) The fifth interface board E. The uplink can access the ATM access/switching device through the ATM interface and access the IP switching/access/aggregation/routing device of the upper-layer IP network through the IP interface. The connection form includes but is not limited to the chain type. , star, tree, ring topology or a combination of these. The ATM interface of the xDSL central office device can be provided through the ATM uplink of the system module or the first interface board A, and the IP interface IP can be an uplink or a third system module interface board C, the fourth or fifth D interface board interface board E directly upstream IP interfaces.

24 is a block diagram of an embodiment of a fourth wideband subscriber access system of the present invention. In the embodiment system shown in Fig. 21, the access multiplexing device is an access multiplexing device network connected through a connection network. Each user access multiplex device (xDSL central office device) can form a chain, star, tree, or ring network with other user access multiplex devices through an ATM or IP interface. The ATM interface can be provided through the ATM uplink of the system module or the first interface board A. The IP interface can directly provide the IP uplink interface through the IP uplink of the system module or the third interface board C, the fourth interface board D or the fifth interface board E.

It is apparent that those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Therefore, it is intended that the present invention cover the modifications and variations of the invention as claimed.

Claims

Rights request

A digital subscriber line access multiplexer, comprising: a system module providing an uplink interface, a service interface board, a service interface board, and a system bus connecting the system module and the service interface board;

The system bus includes a fixed length packet switching bus connected to the fixed length packet interface module; the service interface board includes a first interface board connected to the fixed length packet switching bus.

2. The digital subscriber line access multiplexer according to claim 1, wherein the system module further comprises an Ethernet adapter module connected to the fixed length packet interface module, the Ethernet adapter module Has an IP uplink interface.

3. The subscriber line access multiplexer according to claim 1, wherein the system module further comprises an Ethernet adapter module connected to the fixed length packet interface module, and the Ethernet adapter module Connected Ethernet switch module, the Ethernet switch module has an IP uplink interface.

4. The subscriber line access multiplexer of claim 3, wherein the system bus further comprises a high speed Ethernet switching bus connected to the Ethernet switching module; the service interface board further comprising The third interface board connected to the high speed Ethernet switch bus.

5. The subscriber line access multiplexer of claim 4, wherein the system bus further comprises a low speed Ethernet switching bus connected to the Ethernet switching module; the service interface board further comprising The fourth interface board connected to the low speed Ethernet switching bus.

6. The subscriber line access multiplexer of claim 5, wherein the system module further comprises a multicast processing module coupled to the Ethernet switching module; the system bus further comprising a high-speed multicast bus connected to the multicast processing module; the service interface board further includes a fifth interface board connected to the high-speed multicast bus and the low-speed Ethernet switching bus.

The subscriber line access multiplexer according to any one of claims 1 to 6, wherein the system bus further comprises a fixed length packet multicast bus connected to the fixed length packet interface module, The service interface board further includes a second interface board connected to the fixed length packet multicast bus and the fixed length packet switching bus; and/or the system module further includes an asynchronous transmission connected to the fixed length packet interface module Mode (ATM) uplink processing module, the ATM uplink processing module has an ATM uplink interface.

8. The subscriber line access multiplexer according to claim 7, wherein: the first, second, third, fourth, and/or fifth interface boards are plural; or the fixed length package The multicast bus and fixed length packet switching buses include, but are not limited to, ATM Universal Test and Operational Physical Connection (UTTOPIA) buses, Cell Bus (CELLBUS), ATM Serial Bus Shared Bus, and Star Bus.

A digital subscriber line access multiplexer, comprising: a system module providing an uplink interface, a service interface board providing a service interface, and a system bus connecting the system module and the service interface board; and the feature is:

The system module includes at least an Ethernet switch module having an IP uplink interface; the system bus includes a high speed Ethernet bus connected to the Ethernet switch module, and/or a low speed Ethernet switch bus;

The service interface board includes a third interface board coupled to the high speed Ethernet bus, or / and a fourth interface board coupled to the low speed Ethernet switch bus.

The subscriber line access multiplexer according to claim 9, wherein the system module further comprises an Ethernet adapter module connected to the Ethernet switch module, and is connected to the Ethernet adapter module. The fixed length packet interface module; the system bus further includes a fixed length packet switching bus connected to the fixed length packet interface module; the service interface board further includes a first interface board connected to the fixed length packet switching bus.

The subscriber line access multiplexer according to claim 9 or 10, wherein the system module further includes a multicast processing module connected to the Ethernet switching module, and the system bus further includes a high-speed multicast bus connected to the multicast processing module, the service interface board further comprising a fifth interface board connected to the high-speed multicast bus or connected to the high-speed multicast bus and the low-speed Ethernet switch bus And/or the system module further includes an ATM uplink module connected to the fixed length packet switching module.

12. The digital subscriber line access multiplexer of claim 7 wherein said first, third, fourth and/or fifth interface boards are plurality; or said fixed length packet switching bus comprises But not limited to

ATM universal test and operation physical connection (UTTOPIA) bus, cell bus (CELLBUS), ATM serial bus shared bus and star bus.

A user access device, including a main frame and a slave frame, wherein the main frame includes: System module with IP uplink interface and/or asynchronous transfer mode (ATM) uplink interface for device, interface management, bus control and service processing;

Service interface board, used to provide a service interface;

a system bus, connected to the system module and a service interface board, for transmitting a data message; the slave frame includes:

Service interface board, used to provide a service interface;

a system bus, connected to the service interface board;

The main frame and the secondary frame are cascaded.

The user access device according to claim 13, wherein the system bus of the main frame and the slave frame respectively comprises a fixed length packet switching bus and a fixed length packet multicast bus, and the main frame and the slave frame are The bus is cascaded by the fixed length packet exchange bus and/or the fixed length packet.

The user access device of claim 13, wherein the system module of the main frame comprises an Ethernet switch module and a fixed length packet interface module connected to the system bus, and an Ethernet switch module and a connection The Ethernet adapter module of the long packet interface module; the slave frame further includes a fixed length packet interface module connected to the system bus, wherein the main frame and the slave frame are cascaded by the fixed length packet interface module and the Ethernet adapter module .

16. The user access device of claim 13, wherein the slave frame further comprises a system module having an IP uplink interface and/or an asynchronous transfer mode (ATM) uplink interface; a main frame and a slave frame system The modules respectively have an Ethernet switching module and are cascaded through the Ethernet switching module.

17. A broadband user access system, comprising an ATM network, an ATM access/switching device connected to the ATM network, and an access multiplexing device and a device connected to the ATM access/switching device through a connection network. The user equipment connected to the multiplex device is characterized in that: the access multiplex device includes: a system module that provides an uplink interface, a service interface board that provides a service interface, and a system bus that connects the system module and the service interface board. ;

18. A broadband user access system, comprising an IP network, an IP access/switching/aggregation/routing device connected to the IP network, connected to the IP access/switching/aggregation/routing device through a connection network An access multiplexing device and a user equipment connected to the access multiplexing device, the access multiplexing device includes: a system module that provides an uplink interface, a service interface board that provides a service interface, and a connection system The system bus of the module and the service interface board;

19. A broadband user access system, comprising an ATM network, an IP network, an IP access/switching/aggregation/routing device connected to the IP network, and an ATM access/switching device connected to the ATM network, An access multiplexing device connected to the ATM access/switching device and the IP access/switching/aggregation/routing device and a user device connected to the access multiplexing device by a connection network, characterized in that The access multiplexing device includes: a system module that provides an uplink interface, a service interface board that provides a service interface, and a system bus that connects the system module and the service interface board;

20. The broadband subscriber access system of claim 19, wherein: the access multiplexing device is an access multiplexing device network connected by a connection network.

21. The broadband subscriber access system of claim 17, 18, 19 or 20, wherein said system bus further comprises a high speed Ethernet switching bus coupled to said Ethernet switching module; said service interface The board also includes a third interface board coupled to the high speed Ethernet switch bus.

22. The broadband subscriber access system of claim 21, wherein the system bus further comprises a low speed Ethernet switching bus coupled to the Ethernet switching module; the service interface board further comprising The fourth interface board of the low-speed Ethernet switching bus connection.

The broadband user access system of claim 22, wherein the system module further comprises a multicast processing module connected to the Ethernet switching module; the system bus further includes the multicast The high speed multicast bus connected to the processing module; the service interface board further includes a fifth interface board connected to the high speed multicast bus and the low speed Ethernet switching bus.

1/14-

Management unit user network interface service node interface line port line port

Customer premises

ADSL central office unit separation unit separation unit ADSL subscriber unit

Internet equipment

U-C U-R

Connect to the PSTN or the remote device of the access network. Z interface. Answer the telephone, ISDN terminal, etc.

figure 1