KR20020054389A - Method for virtual LAN in DSLAM - Google Patents

Abstract

PURPOSE: A method for realizing a virtual LAN in DSLAM(DSL Access Multiplexer) is provided to efficiently use resources by reducing traffic congestion due to broadcast and configuring virtual work groups, and share resource and maintain the security in even case that a user moves to the other place. CONSTITUTION: Each transmitting subscriber board stores Ethernet data input through each channel in FIFO and transmits Ethernet data after attaching a tag consist of VLAN ID to the front of Ethernet frame during one clock(ST21). Each receiving subscriber board received Ethernet data through a GTL bus, stores the received data at the FIFO, and analyzes the tag by each channel for receiving data belong to the identical VLAN(ST22).

Description

Implementation method of virtual LAN in DSL {Method for virtual LAN in DSLAM}

The present invention relates to a virtual LAN (VLAN) implementation method in a DSLM (DSL Access Multiplexer, Digital Subscriber Transmission Line Multiplexer). The present invention relates to a virtual LAN implementation method in DSLAM that makes it possible to efficiently use and to be suitable for sharing resources and securing security with the same VLAN members even when users move from place to place.

Digital Subscriber Line Access Multiplexers (DSLAMs) are typically network equipment installed in telephone offices that receive signals from digital subscriber line connections from multiple customers and send signals to high-speed backbone lines using multiplexing techniques. Depending on the product, a DSLAM multiplexer may connect DSL lines with a combination of ATM, frame relay, or IP networks. DSLAM enables telephone companies to provide high-speed telephone line technology (DSL) and high-speed backbone network technology (ATM) to business and home users.

1 is a block diagram including a general DSLAM.

Here, reference numeral 10 is a router connected to the DSLAM 20, 20 is a DSLAM, and 30 is an ADSL subscriber modem 30.

So the DSLAM 20 is connected to the router 10 and the ATM switch or transmission equipment in one axis, and the other axis is connected to the ADSL subscriber modem 30.

In addition, there is a VLAN configuration based on a LAN switch, and a VLAN configuration in an ATM (Asynchronous Transfer Mode) -based DSLAM can be configured by setting one LAN emulation group to the same VLAN.

Multiple VLANs can be supported by placing one or more LAN Emulation Clients (LECs) on an ATM interface connected to an ATM.

Because LECs on an ATM interface are treated as separate Ethernet ports, LECs on devices connected to one ATM can be members of different VLANs.

In the ATM-based DSLAM according to the prior art, VLANs may be implemented through LAN emulation.

Compared with a conventional LAN, ATM is a connection-oriented network, that is, a VCC (Virtual Channel Connection) must be established between terminals that want to transmit and receive before data is transmitted.

Based on this, to accommodate broadcasting and multicasting provided by the existing LAN, traffic performance can be improved by using a VLAN.

2 is a flowchart illustrating a VCC implementation method in a conventional DSLAM.

As shown therein, steps (ST11) (ST12) of determining whether the LEC has already set the VCC by examining the table mapping the destination MAC address and the VCC; If the LEC has not yet set up the VCC, the LEC requests the ATM address of another LEC that knows the MAC address, and updates the VCC-MAC mapping table (ST13) (ST14).

So, conventionally, to find out whether the LEC (PC, WS, bridge, switch, router, etc.) to send data has already set the VCC, the table that maps the destination MAC address to the VCC is examined.

If not, the VCC setup process is performed before data transfer.

That is, when the LEC wants to know the ATM address of another LEC that knows the MAC address, it requests the LAN Emulation Server (LES) using the LAN Emulation Address Resolution Protocol (LE-ARP).

As a prerequisite for this, each LEC must have LES and VCC pre-configured.

This process is called an ARP (Address Resolution Process), which recognizes the terminal ATM address and requests the VCC setting. After the setting, the VCC-MAC mapping table is updated.

However, in the conventional ATM-based DSLAM, in order to perform LAN emulation, there is an inconvenience in that a separate software porting is required for the interface directly with the ATM and the interface with the existing LAN. In addition, a separate LAN Emulation Server (LES), LAN Emulation Configuration Server (LECS), and Broadcast and Unknown Server (BUS) are required for VCC setup, and high cost is required. There was a problem that can lower the.

Accordingly, the present invention has been proposed to solve the above-mentioned conventional problems, and an object of the present invention is to reduce the congestion of traffic due to broadcast and to make use of resources efficiently by configuring a virtual workgroup, and It is to provide a virtual LAN implementation method in DSLAM that can share resources and maintain security with the same VLAN member even if the user moves to another location.

Virtual LAN implementation method in the DSLAM according to an embodiment of the present invention to achieve the above object,

A first step of transmitting data by attaching a tag configured with a VLAN ID in front of the Ethernet frame for one clock; After the first step, the receiving side analyzes a tag for each channel and includes a second step of receiving data belonging to the same VLAN.

1 is a block diagram including a general DSLAM,

2 is a flowchart illustrating a VCC implementation method in a conventional DSLAM.

3 is a flowchart illustrating a virtual LAN implementation method in a DSLAM according to the present invention;

4 is a diagram illustrating the structure of a tag in FIG. 3.

Explanation of symbols on the main parts of the drawings

10: Router 20: DSLAM

30: ADSL subscriber modem

Hereinafter, an embodiment according to the present invention as described above, the technical spirit of the virtual LAN implementation method in the DSLAM will be described with reference to the drawings.

3 is a flowchart illustrating a virtual LAN implementation method in a DSLAM according to the present invention, and FIG. 4 is a diagram illustrating a structure of a tag in FIG. 3.

As shown therein, a first step (ST21) of transmitting data by attaching a tag configured with a VLAN ID for one clock before the Ethernet frame at the transmitting side; After the first step, the receiving side performs a second step (ST22) of receiving data belonging to the same VLAN by analyzing a tag for each channel.

The operation of the virtual LAN implementation method in the DSLAM according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

First, as shown in the tag structure of FIG. 4, the transmitting side transmits data by attaching a tag configured with a VLAN ID for one clock before a general Ethernet frame. The receiver analyzes the tag for each channel and receives data belonging to the same VLAN.

In addition, VLANs are always enabled for data received from networks such as DPUs (Data Processing Units), VLAN ID is "0", and 64 subscriber channels are VLAN enabled / disabled. / Disable), and VLAN ID from 1 to 15 can be set when enabled.

This operation of the present invention will be described in more detail.

In the packet-based DSLAM 20, 16 subscriber slots are configured, and one subscriber slot is configured with 4 channels, which can accommodate a total of 64 subscribers.

Sixteen subscriber boards are connected on the backplane via the GTL bus to send and receive data.

Each subscriber board configures VLAN enable / disable for each of four channels, and if enabled, has a database of configured VLAN ID values.

Thus, each subscriber board stores the Ethernet data input to each channel in FIFO (First In First Out) and transmits it with a tag of 5 bits for one clock before sending it to the GTL bus.

Among the bits, the most significant bit (MSB) bit is a VLAN enable / disable value, and the next 4 bits indicate a VLAN ID at enable time.

If each subscriber board receives Ethernet data through the GTL bus, it stores the received data back into the FIFO and analyzes the received tag.

Data received from the network is received on all four channels, and data received from other subscriber boards is compared to the database for the four channels, and if there is a matching VLAN ID, the data is received on that channel.

In case of having the same VLAN ID in each subscriber board, it is set as one group to transmit and receive.

As such, the present invention reduces traffic congestion due to broadcasts, configures a virtual workgroup to efficiently use resources, and shares resources with the same VLAN members and maintains security even when users move from place to place. will be.

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the virtual LAN implementation method in the DSLAM according to the present invention reduces the traffic congestion caused by broadcast, configures a virtual workgroup to efficiently use resources, and when a user moves to a place This also has the effect of sharing resources and securing security with the same VLAN members.

In addition, the present invention also has the effect of reducing the cost more efficiently when the user moves, adds, changes, etc. in the VLAN of the DSLAM transmitting the packet using the DSL line.

In addition, the present invention provides a security function so that only a specific group can use important data requiring security, efficient use of resources due to management of broadcast data, and improved performance and reduced traffic delay. .

Claims (1)

A first step of transmitting data by attaching a tag configured with a VLAN ID in front of the Ethernet frame for one clock; And a second step of receiving a data belonging to the same VLAN by analyzing a tag for each channel after the first step.