KR100462896B1 - Dsl access multiplexor and network system using it - Google Patents

Abstract

The present invention relates to a digital subscriber line multiplexing device and a network system using the same. The digital subscriber line multiplexing device of the present invention receives an xDSL signal and demodulates an xDSL signal to extract an ATM cell during up packet processing. ATU-C modulates ATM cells into xDSL signals during processing, and ATM cells received from ATU-C during up packet processing convert IP packet information into IP packet information, and converts IP packet information back into virtual LAN IP packets. IP matching means for converting information into a form of a virtual LAN ID, adding a virtual LAN ID, and processing the down packet, receiving the information of a virtual LAN IP packet form, converting the information into an IP packet form, and converting the information of the IP packet form into an ATM cell. It characterized by having a.

Accordingly, the apparatus for digital subscriber line multiplexing according to the present invention provides an interface for using a virtual LAN service for a general subscriber using an Internet service regardless of physical arrangement.

In addition, a multi-digital subscriber line multiplexing device that provides a virtual LAN function provides an internal broadcast function to provide the effect of traffic distribution of the ISP switch.

Description

Digital subscriber line multiplexing device and network system using same {DSL ACCESS MULTIPLEXOR AND NETWORK SYSTEM USING IT}

The present invention is a digital subscriber line multiplexer device (DSL Access Multiplexor below: DLSAM DSLAM), and more particularly in the DSLAM device VLAN on (Virtual LAN following: VLAN) digital subscriber line multiplexing apparatus to support the services and networks that use them It is about the system.

In general, a virtual LAN (VLAN) refers to a group formed by segmenting a plurality of nodes into a broadcast domain regardless of the physical location of network nodes. This divides the resources and users on the network into different workgroups, significantly reducing traffic between segments.

VLANs enhance network security by making network resources available only to authorized users. finally. VLANs improve security by restricting network resource access, reducing broadcast traffic by reducing the size of the broadcast domain, and consequently improving overall network performance.

A segment here refers to a part of a network system that is bounded by a bridge, router, hub, or switch. Dividing a network into several segments is one of the most common ways to increase bandwidth on a LAN. If the segments are properly partitioned, most network traffic can use up to 10 Mbps of bandwidth within a single segment. Hubs or switches are devices used to connect each segment to a LAN.

The network system for supporting a conventional virtual LAN service is divided into a network system based on a LAN switch and a network system based on a DSLAM.

LAN switch-based network system is mainly used for short-range private network system such as in-company network system, and DSLAM-based network system is mainly used for remote network system using DSLAM which is mainly located in the telephone company.

1 is a diagram schematically illustrating a network system based on a conventional LAN switch.

Referring to FIG. 1, the network system includes a plurality of terminals 11a through 11e and a plurality of switches 12a through 12b, and each of the plurality of switches 12a through 12b includes a plurality of terminals 11a through 12b. 11e) allocates a virtual LAN ID to each of the plurality of terminals 11a-11e for each port.

When data is transmitted from each of the plurality of terminals 11a to 11e having the virtual LAN IDs allocated as described above, the switch 12a analyzes the virtual LAN ID (VLANID = 1) of the terminal 11a transmitting the data. The data is broadcasted to each of the plurality of terminals 11c and 11d having the same virtual LAN ID as the terminal 11a that transmits the data.

A network system based on a conventional LAN switch provides a virtual LAN service in a local area network system using a virtual LAN function of a LAN switch. Therefore, there is a problem that the network system for a local area network system based on a conventional LAN switch is not suitable for use in a remote network system.

2 is a diagram schematically showing a network system based on a conventional DSLAM.

Referring to FIG. 2, the DSLAM-based network system includes a plurality of terminals 21a to 21d, a plurality of ADSL Terminal Unit-Remotes (ADSL subscriber units) 22a to 22d, and a DLSAM 23. ) and remote access server (Access remote Access server below: RAS) (24) Internet service provider (Internet service provider or less: ISP) is a switch (25).

When the terminal 21a attempts to access the Internet network, the subscriber information is converted into an ATM cell through the ATU-R 22a, and is modulated into an xDSL signal and transmitted to the DSLAM 23.

The DSLAM 23 terminates the xDSL signal and transmits an ATM cell to the RAS 24.

The RAS device 24 terminates the ATM cell transmitted via the DSLAM 23 and converts the information of the IP packet to broadcast the virtual LAN service at the switch 25 of the ISP.

The network system based on the conventional DSLAM is mainly based on ATM-based DSLAM equipment of DSLAM, so it was necessary to use a separate RAS device. However, it is not only difficult to construct such a network system using RAS, but there is also a problem that speed congestion occurs due to the traffic load on the ISP switch as the number of general subscribers using the Internet increases exponentially.

Accordingly, an object of the present invention is to provide a digital subscriber line multiplexing device for providing a virtual LAN service and a network system using the same.

In order to realize the above object, the digital subscriber line multiplexing apparatus of the present invention receives an xDSL signal during demodulation of up packets, demodulates an xDSL signal, extracts an ATM cell, and modulates an ATM cell into an xDSL signal during down packet processing. ATU-C and uplink packet processing converts ATM cells received from ATU-C to IP packet information and converts IP packet information back to virtual LAN IP packet information to add a virtual LAN ID. In the case of down packet processing, IP matching means for receiving virtual LAN IP packet information, converting the information into IP packet information, and converting the IP packet information into ATM cells is provided.

The network system of the present invention for realizing the above object modulates the subscriber information of the terminal into ATM cells during up packet processing, modulates the ATM cells into xDSL signals, and demodulates xDSL signals from the digital subscriber line multiplexing device during down packet processing. It consists of ATU-R, ATU-C, and IP matching device that extracts ATM cell, converts ATM cell into IP packet form, and transmits it to terminal, and demodulates xDSL signal transmitted from ATU-R during up packet processing. Adds a virtual LAN ID by extracting the cell and converting the ATM cell into the information of the virtual LAN IP packet, and converting the ATM packet into the ATM cell and modulating the ATM cell into an xDSL signal when processing down packets. Subscriber line multiplexing device, and during up packet processing, receives virtual LAN IP packet information from digital subscriber line multiplexing device and And in the down packet is processed with the received IP packet in the form of VLAN information from the network, the network is characterized in that a switch for transmitting a digital subscriber line multiplexer devices.

1 is a diagram schematically illustrating a network system based on a conventional LAN switch.

2 is a diagram schematically showing a network system based on a conventional DSLAM.

3 is a diagram schematically illustrating a network system based on the DSLAM of the present invention.

4 is a block diagram of a DSLAM of the present invention.

5 is a structural diagram of a virtual LAN IP packet of the present invention.

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

33: DSLAM

40: ATU-C 50: IP matching device

51: system management department

52a to 52d: subscriber management interface unit

53a to 53b: bridge management interface unit

54a to 54b: virtual LAN management interface unit

55a to 55b: LAN management module

Hereinafter, a digital subscriber line multiplexing device and a network system using the same will be described with reference to the accompanying drawings.

3 is a diagram schematically illustrating a network system based on the DSLAM of the present invention.

Referring to FIG. 3, the DSLAM-based network system includes a plurality of terminals 31a to 31d, a plurality of ATU-Rs 32a to 32d, a DSLAM device 33, and an ISP switch 34. It consists of.

The terminal 31a is a subject performing substantial data communication.

The ATU-R 32a is located between the telephone line of the general subscriber and the home distribution network.

In the case of up packet processing in which data is transmitted from the subscriber side to the ISP switch 34 from the subscriber side to the ATU-R 32a to 32d, when the terminal is connected to the Internet network, the subscriber information of the terminal is modulated by ATM cellization and xDSL signals. It transmits to DSLAM 33 located in the telephone office.

During down packet processing in which data is transmitted from the ISP switch 34 to the subscriber side, the xDSL signal received by the DSLAM 33 is demodulated to extract data from the ATM cell, and the data is transmitted to the terminal 31a.

The ATM-based DSLAM uses the ATM protocol, which consists of a management plane, a control plane, and a user plane. The management plane is divided into plane management and layer management. Plane management performs management functions related to the entire system and coordinates with all planes.

Thus, plane management does not have a hierarchy. Layer management performs management functions related to resources and parameters of protocol entities. And it processes OAM information of each layer. The control plane and user plane are divided into physical layer, ATM layer, ATM Adaptation Layer (AAL), and upper layer.

The physical layer is concerned with the specification of the transmission medium and the signal encoding method. Data rates defined at the physical layer are 155.52 Mbps and 622.08 Mbps. Other data rates higher or lower are possible.

The second layer of the protocol structure relates to ATM functionality. There is an ATM layer that is common to all services that support the packet transfer function and an ATM adaptation layer that depends on the service. The ATM layer defines the data transmission of fixed cells and also defines the use of logical connections. To use ATM, an adaptation layer is needed to support other information transfer protocols that are not based on ATM. The AAL maps the information of the upper layer to the ATM cell that can be transmitted in the ATM network, and gathers the information from the ATM cell to advance to the upper layer.

The reason why the ATU-R 32a modulates subscriber information of the terminal into ATM cellization and xDSL signals is to convert the subscriber information to conform to this ATM protocol.

xDSL signal is a high-speed data transmission technology using the existing telephone line. As a means to solve the problem of efficient transmission of data in the recent explosive trend, the xDSL signal can be used more for the high-speed data transmission. It is a technology that has been studied in a way.

The ATU-R 32a supports ADSL and VDSL and the first layer of ATM protocol for data communication of terminals using ISDN and telephone by modulating and transmitting the information generated by the subscriber into xDSL signals.

The ATM cell is intended to support the DSLAM device 33 based on ATM as the second layer of the ATM protocol, which opens and maintains a path for physical connection with a partner of an address identified at the network layer.

DSLAM (33) is a network equipment usually installed in a telephone station, receives the transmission data of the terminal 31a through the ATU-R, adds a virtual LAN ID to the data of the terminal, and then uses a multiplexing technique to connect to the high-speed backbone line. It is responsible for sending signals.

The DSLAM 33 is composed of an ATU-C (ADSL Terminal Unit-Center: ADSL Telephone Station Device) 40 and an IP Matching Device 50.

In the up packet processing, the ATU-C 40 terminates the xDSL signal transmitted from the plurality of ATU-Rs 32a to 32d, and the IP matching device 50 terminates the ATM cell, and the software matches the IP. And by using the hardware to convert the information in the form of a virtual LAN IP packet to the IP matching function to transmit to the switch of the ISP to support the virtual LAN service.

During down packet processing, the ISP switch 34 receives the information of the virtual LAN IP packet type, analyzes the virtual LAN ID of the information of the virtual LAN IP packet type, and converts the ATM cell into a subscriber with the corresponding virtual LAN ID. It transmits to the connected ATU-Rs 32a to 33d.

In addition, the IP matching device 50 supports an internal broadcasting function to perform an IP packet broadcasting function between terminals using the same virtual LAN ID.

The ISP switch 34 receives virtual LAN IP packet information from the DSLAM 33 and connects it to the network in the up packet processing.

During down packet processing, information in the form of a virtual LAN IP packet is transmitted to the DSLAM 33 connected to the subscriber having the corresponding virtual LAN ID.

ISP switch 34 is a network device that selects a path or line to send unit data to the next destination. The ISP switch 34 may also include a router function, which is a device that can determine which route should be sent to the route, or more specifically, adjacent network points.

Referring to the network system based on the DSLAM of the present invention shown in Figure 3 as follows.

Each of the plurality of terminals 31a to 31d transmits and receives data to perform substantial data communication.

In the up packet processing, when the terminal 31a transmits data, the ATU-Rs 32a to 32d convert the subscriber information of the terminal 31a into an ATM cell, modulate it into an xDSL signal, and transmit the data to the DSLAM 33.

During down packet processing, the xDSL signal received by the DSLAM 33 is demodulated to extract an ATM cell, and the ATM cell is converted into an IP packet to transmit data to the terminal 31a.

The DSLAM 33 demodulates the xDSL signal transmitted from the ATU-Rs 32a to 33d through the ATU-C 40 to extract the ATM cell and transmits the extracted ATM cell to the IP matching device 50.

The IP matching device 50 converts the ATM cell received from the ATU-C 40 into information in an IP packet form so that the ISP switch 34 can recognize the IP cell. After converting the information into a virtual LAN ID is added to the ISP switch (34).

During down packet processing, the ISP switch 34 receives the information of the virtual LAN IP packet type, analyzes the virtual LAN ID of the information of the virtual LAN IP packet type, and converts the ATM cell into a subscriber with the corresponding virtual LAN ID. It transmits to the connected ATU-Rs 32a to 33d.

The ISP switch 34 connects the virtual LAN IP packet type information to the network during the up packet processing, and the DSLAM 33 connected with the subscriber having the corresponding virtual LAN ID during the down packet processing. To be sent).

4 is a block diagram of a DSLAM of the present invention.

Referring to FIG. 4, the DSLAM 33 includes an ATU-C 40 and an IP matching device 50. The IP matching device includes a system management unit 51 and a plurality of subscriber management interface units 52a to 52d. A plurality of bridge management interface units 53a to 53b, a plurality of virtual LAN management interface units 54a to 54b, and a LAN interface management module 55 are provided.

The ATU-C 40 demodulates xDSL signals received from a plurality of ATU-Rs 32a through 32d during up packet processing, extracts an ATM cell, analyzes the VPI / VCI identifiers of the ATM cell, and manages the same ATM. The ATM cell is transmitted to the subscriber management interface having the information.

During down packet processing, ATM cells are received from each of a plurality of subscriber interface units, modulated into xDSL signals, and transmitted to the corresponding ATU-R.

The system management unit 51 includes a plurality of subscriber interface units 52a to 52d, a plurality of bridge management interface units 53a to 53b, which are logical interfaces of the IP matching device 50, and a plurality of virtual LAN management interface units 54a to 54, respectively. 54b) and establish a logical path for each of these plurality of interfaces.

For example, the plurality of subscriber management interface units 52a to 52c having information of the plurality of ATU-Rs 32a to 32c assigned the same virtual LAN ID may be logically connected to the same bridge management interface unit 52a. The path is set.

The subscriber management interface 52a manages the information of the plurality of ATU-Rs 32a to 32d connected to the DLASM 33. In the up packet processing, the ATM cell, which is the subscriber's data, is terminated and converted into IP packet information and transmitted to the bridge management interfaces 53a to 53b along the logical path.

During down packet processing, information in the form of IP packets transmitted from the bridge management interface unit 53a connected through a logical path is converted into an ATM cell and transmitted to the ATU-C.

In addition, the up and down packet processing capacity of each of the plurality of terminals 31a to 31d is limitedly managed.

The bridge management interface units 53a to 53b perform a bridge role and internal broadcasting role between the subscriber management interface units 52a to 52d and the virtual LAN management interface units 54a to 54b.

A plurality of subscriber management interface units 52a to 53c having information of a plurality of ATU-Rs having the same virtual LAN ID are connected to the same bridge management interface unit 53a.

The bridge management interface units 53a to 53b manage the dynamic memory table for internal broadcast.

Accordingly, when the plurality of subscriber management interface units 52a to 53c are connected to the same bridge management interface unit 53a at the time of up packet processing, the bridge management interface unit 53a to configure the plurality of subscriber management interface units 52a to 53c. When the information in the form of an IP packet is received through one of the subscriber management interface units 52a, a broadcast function of a packet transmitted and received by all the subscriber management interface units 52b to 53c connected to the corresponding bridge management interface unit 53a. Do this.

During down packet processing, the IP packet transmitted from the virtual LAN interface management module 54a connected by the logical path is transmitted to the plurality of subscriber management interfaces 52b through 53c connected by the bridge management interface unit 53a and the logical path. do.

The virtual LAN management interface 54a converts the information of the IP packet form transmitted through the bridge management interface 53a into the information of the virtual LAN IP packet form and adds a virtual LAN ID to the logical path during the up packet processing. Follows the transmission to the LAN interface management module 55.

During down packet processing, the virtual LAN IP packet type information is received from the LAN interface management module 55, converted into IP packet type information, the virtual LAN ID is deleted, and the corresponding bridge management interface unit 53a follows a logical path. To send.

The LAN interface management module 55 transmits information in the form of a virtual LAN IP packet transmitted from each of the plurality of virtual LAN management interface units 54a to 54b to the ISP switch.

During down packet processing, the virtual LAN IP packet is received from the ISP switch 34 and transmitted to the virtual LAN management interface units 54a to 54b corresponding to the virtual LAN IP packet.

Looking at the operation of the DSLAM of the present invention shown in Figure 4 as follows.

Assume that it is connected to three ATU-Rs connected to terminals assigned a virtual LAN ID of 1 to DSLAM and one ATU-R connected to a terminal assigned a virtual LAN ID of 2 respectively.

The system management unit 51 of the DSLAM includes a plurality of subscriber interface units 52a to 52d which are logical interfaces of the IP matching device 50, bridge management interface units 53a to 53b, and virtual LAN management interface units 54a to 54b. Subscriber interface units 52a to 52d, bridge management interface units 53a to 53b, and virtual LAN management interface units 54a to 54b.

The first subscriber management interface unit 52a to the third subscriber management interface unit 52c having subscriber information assigned with the same virtual LAN ID 1 establish a logical path so as to be connected to the first bridge management interface unit 53a. The fourth subscriber management interface 52d having subscriber information assigned with the virtual LAN ID 2 establishes a logical path to be connected to the second bridge management interface 53a.

The first bridge management interface 52a establishes a logical path so as to be connected to the first virtual LAN management interface 53a, and the second bridge management interface 52b is connected to the second virtual LAN management interface 53b. do.

The ATU-C 40 receives the xDSL signal from the first ATU-R 32a and demodulates the ATM cell during up packet processing, extracts the ATM cell, analyzes the VPI / VCI information of the ATM cell, and then analyzes the first subscriber management interface unit. Send to 52a.

In the case of down packet processing, when an ATM cell is received from the first subscriber interface unit 52a, it is modulated into an xDSL signal and transmitted to the first ATU-R 32a.

The first subscriber management interface 52a converts the corresponding ATM cell into IP packet type information having an Ethernet frame structure when the uplink packet is processed, and the converted IP packet type information is converted into the first bridge management interface part 53a. To send).

During down packet processing, the IP packet transmitted from the first bridge management interface unit 53a is converted into an ATM cell and transmitted to the ATU-C 40.

The first bridge management interface 53a receives the IP packet information during the up packet processing, and the second subscriber management interface 53 is connected to the first bridge management interface 53a in a logical path for internal broadcast. The packet is transmitted to the 52b and the third subscriber management interface 52b. Also, it transmits it to the first virtual LAN management interface 54a.

Even during down packet processing, information in the form of IP packets transmitted from the first virtual LAN management interface 54a is equal to the first subscriber management interface 52a and the second subscriber management interface unit (a) connected to the same logical path. 52b), and transmits it to the third subscriber management interface unit 52c.

The first virtual LAN management interface 54a converts the received IP packet information into a virtual LAN IP packet having an Ethernet frame tag header structure, and adds a virtual LAN ID to the LAN interface management module 55. do.

When the down packet is processed, the virtual LAN IP packet transmitted to the LAN interface management module 55 is converted into IP packet type information to delete the virtual LAN ID, and then the first LAN management interface 53a connected by a logical path. send.

The LAN interface management module 55 receives the virtual LAN IP packet and transmits it to the ISP switch 34.

During down packet processing, the virtual LAN IP packet is received from the ISP switch 34 and transmitted to the first virtual LAN management interface 52a.

5 is a structural diagram of a virtual LAN IP packet of the present invention.

The structure of the IP packet of the subscriber management interface units 52a to 52d has an Ethernet frame structure based on IEEE 802.1P of FIG.

The virtual LAN interface units 54a to 54b receive the IP packet and convert the IP packet into a virtual LAN IP packet having an Ethernet frame tag header structure based on the IEEE 802.1Q VLAN of FIG. 5 so that the ISP switch can recognize the IP packet. Add the virtual LAN ID in the Tag Control Information (TCI) field after the length / type field of the Ethernet frame.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art various modifications and changes to the present invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

As described above, the digital subscriber line multiplexing device and the network system using the same provide an interface that can use a virtual LAN service regardless of physical arrangement for a general subscriber using the Internet service.

In addition, the digital subscriber line multiplexing device that provides the virtual LAN function and the network system using the same provide the internal broadcast function to provide the effect of traffic distribution of the ISP switch.

Claims (6)

An ATU-C which receives an xDSL signal to demodulate the xDSL signal to extract the ATM cell during up packet processing, and modulates the ATM cell to an xDSL signal during down packet processing; And During the up packet processing, the ATM cell received from the ATU-C is converted into IP packet information, and the IP packet information is converted back into virtual LAN IP packet information to add a virtual LAN ID. In case of packet processing, digital subscriber line multiplexing is provided with IP matching means for receiving the information in the form of the virtual LAN IP packet, converting the information in the form of the IP packet, and converting the information in the form of the ATM packet back into ATM cells. Device. The method of claim 1, wherein the IP matching means A subscriber which manages a subscriber connected to the digital subscriber line multiplexing device and converts the ATM cell into the IP packet information during up packet processing, and receives and converts the ATM packet information into an ATM cell during down packet processing. Management means; In the case of up packet processing, the IP packet form is converted into information in the form of the virtual LAN IP packet, and a virtual LAN ID is added. Virtual LAN management means for converting the information of the virtual LAN ID to delete; Bridge management means for transmitting and receiving the information in the form of the IP packet between the subscriber management means and the virtual LAN management means; In the up packet processing, the virtual LAN IP packet type information transmitted from the virtual LAN management means is transmitted to an ISP switch. In the down packet processing, the virtual LAN IP packet type information is received from the ISP switch. LAN management means for transmitting to the management means; And And a system management means for generating the subscriber management means, the bridge management means, and the virtual LAN management means of the IP matching means, and setting a logical path of each of the plurality of management means. Circuit multiplexing device. The method of claim 2, wherein the subscriber management means And managing processing capacity during up or down packet processing of the IP packet information. The method of claim 2, wherein the bridge management means A digital subscriber line multiplexing device, characterized in that it performs an internal broadcast function. The method of claim 2, wherein the virtual LAN IP packet is A digital subscriber line multiplexing device having an Ethernet frame tag header structure based on IEEE 802.1Q VLAN. During up packet processing, the subscriber information of the terminal is converted into an ATM cell, and the ATM cell is modulated into an xDSL signal. In the down packet processing, the xDSL signal is demodulated from a digital subscriber line multiplexer to extract the ATM cell. ATU-R which converts the data into the form of the IP packet and sends it to the terminal; Equipped with an ATU-C and an IP matching device, during up packet processing, demodulate the xDSL signal transmitted from the ATU-R, extract the ATM cell, convert the ATM cell into information in the form of a virtual LAN IP packet, A digital subscriber line multiplexing device for adding a LAN ID and converting the virtual LAN IP packet type information into the ATM cell and modulating the ATM cell into the xDSL signal when down packet processing is performed; And In the up packet processing, the virtual LAN IP packet type information is received from the digital subscriber line multiplexing device and connected to a network. In the down packet processing, the virtual LAN IP packet type information is received from the network network. A network system using a digital subscriber line multiplexing device, comprising: a switch for transmitting to a digital subscriber line multiplexing device.